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J H Suh

Publications and source records attributed to J H Suh.

At least 37 records · Page 2Linked to original sources
PubMed2001

Comparison of different enrichment broths and background flora for detection of heat-injured Listeria monocytogenes in whole milk.

Various primary enrichment broths, including University of Vermont medium (UVM), Listeria enrichment broth (LEB), modified LEB, and aerobic and anaerobic L-PALCAMY, were compared with aerobic and anaerobic Pennsylvania State University (PSU) broths for the detection of severely heat-injured (62.8 degrees C for 5, 10, or 15 min; no colony appearance after heat injury on aerobic Trypticase soy agar containing 0.6% yeast extract and modified Oxford medium) Listeria monocytogenes Scott A. Anaerobic conditions were produced by adding L-cysteine and then purging the headspace with N2. The effect of uninjured background flora (10(3) CFU/ml of Enterococcus faecium) on frequency of detection was examined. Anaerobic PSU broth resulted in the lowest false-positive rate and the highest frequency of detection of severely heat-injured L. monocytogenes compared with UVM, LEB, and modified LEB (P < 0.05). The presence of E. faecium significantly enhanced the detection of heat-injured (10 min at 62.8 degrees C) L. monocytogenes in aerobic and anaerobic PSU and aerobic and anaerobic L-PALCAMY broths (P < 0.05). The highest concentration of uninjured E. faecium (>10(6) CFU/ml) inhibited the detection of heat-injured L. monocytogenes (P < 0.05). A heat-resistant, LiCl-tolerant Lactobacillus isolate from raw milk increased the rate of both false-positive and false-negative reactions.

Aerobiosis↗
PubMed2000

Analysis of the morphologic changes of Monascus sp. J101 cells cocultured with Saccharomyces cerevisiae.

Changes in cell life cycle and intracellular structure of Monascus sp. J101 by coculture with Saccharomyces cerevisiae were investigated. Cocultured Monascus cells showed accelerated cell growth and reproduction. Production of asexual and sexual spores was used as an efficient method of cell proliferation. Formation of meiotic (sexual) spores was more frequently observed in the cocultured Monascus cells. The interior structure of a cocultured cell was characterized by increased numbers and sizes of vacuoles. The vacuoles probably serve as repositories for pigment storage. Pigments produced by the cocultured Monascus cells were more hydrophobic than pigments produced by control cells with no coculture.

Ascomycota↗
PubMed2000

Physiological analysis on novel coculture of Monascus sp. J101 with Saccharomyces cerevisiae.

During the fermentation process of Monascus 3101, coculture with Saccharomyces cerevisiae culture filtrate stimulated the formation of reproductive spores, which subsequently resulted in accelerated Monascus cell reproduction and proliferation. Protein kinase C activity was also detected. Chitinase (EC 3.2.1.14), a 120-kDa secretory protein, was purified from the S. cerevisiae culture filtrate as the effector. Monascus cells cocultured with a S. cerevisiae culture filtrate contained approximately four times more total lipids (mainly linoleic and oleic acid) than Monascus cells without coculture. Addition of exogenous fatty acids only contributed to an increase in cell mass. There was no effect on spore formation or pigment production. There were significant changes in patterns and amounts of expressed proteins in cocultured Monascus cells compared to control cells with no coculture.

Ascomycota↗
PubMed2000

Application of recursive partitioning analysis and evaluation of the use of whole brain radiation among patients treated with stereotactic radiosurgery for newly diagnosed brain metastases.

PURPOSE: To evaluate the usefulness of whole brain radiotherapy (WBRT) and of the Radiation Therapy Oncology Group recursive partitioning analysis (RPA) for brain metastases among patients receiving stereotactic radiosurgery (SRS). METHODS AND MATERIALS: A retrospective analysis was performed on 135 patients who underwent linear accelerator (Linac) (n = 73) or Gamma Knife (n = 62) SRS for newly diagnosed brain metastases at the Cleveland Clinic Foundation between 8/89 and 12/98. Univariate and multivariate analyses were performed to evaluate the effects of age, primary site, control of the primary, interval to development of brain metastases (disease-free interval [DFI]), number of brain metastases, presence of extracranial metastases, Karnofsky performance status (KPS), treatment of brain metastases, and RPA class on overall survival. RESULTS: Application of the RPA classification revealed 29 patients fit the criteria for class I, 96 for class II, and 10 for class III. All of the patients underwent SRS. Fifty-seven patients also received WBRT at the time of initial presentation (SRS and immediate WBRT), and 78 patients received WBRT only if CNS relapse occurred (SRS alone). The median survival for all patients was 7.9 months (range: 1.1-90.1), and was 11.2 months for RPA class I compared to 6. 9 months for RPA classes II-III (p = 0.016). Median survival was 10. 5 months following SRS alone compared to 6.4 months following SRS and WBRT (p = 0.07). On univariate analysis, KPS >/= 80% (p = 0.002) and absence of systemic disease (p = 0.013) were also associated with longer survival, whereas control of the primary, DFI, and number of brain metastases did not have an impact. Multivariate analysis revealed only RPA class (p = 0.023) to be an independent predictor for overall survival, whereas treatment group (p = 0.079) was only marginally significant. At 2 years, immediate WBRT improved control at the original site of metastases (80% vs. 52%, p = 0.03) and prevention of new metastatic sites within the brain, 74% vs. 48% (p = 0.06). The 2-year intracranial disease-free survival was 60% following SRS and WBRT compared to only 34% following SRS alone (p = 0.03). CONCLUSIONS: Despite the inherent biases to select more favorable patients for SRS, the RPA class retains its prognostic value. Omission of WBRT from the initial management was not detrimental in terms of overall survival; however, progressive disease occurred in over 50% of patients treated in this manner. Further studies are required to determine which, if any, patients should be considered for SRS with WBRT held in reserve.

Age Factors↗
PubMed2000

The role of whole brain radiotherapy and stereotactic radiosurgery on brain metastases from renal cell carcinoma.

PURPOSE: We reviewed our experience with patients who have undergone stereotactic radiosurgery (SRS) for brain metastases secondary to renal cell carcinoma (RCC). Analysis was performed to determine the survival, local control, distant brain failure (DBF), and then to define which tumors may not require upfront whole-brain radiotherapy (WBRT). METHODS AND MATERIALS: Twenty-nine patients with 66 tumors underwent SRS from 1991 to 1998. Median follow-up from time of brain metastases diagnoses relative to each tumor was 12.5 months and 6.8 months from the time of SRS. Median SRS dose was 1,800 cGy to the 60% isodose line. Three patients had undergone SRS for previously treated tumors. RESULTS: Median survival time from diagnosis was 10.0 months. Overall survival was not affected by age, addition of WBRT, number of lesions, tumor volume, or the presence of systemic disease. Of the 23 patients with follow-up neuroimaging, 4 of 47 (9%) tumors recurred. The addition of WBRT did not improve local control. Of the 13 patients who presented with a single lesion, 3 went on to develop DBF (23%), while 6 of the 10 patients who presented with multiple metastases developed DBF (60%). CONCLUSION: Patients with brain metastases secondary to RCC treated by SRS alone have excellent local control. The decision of whether or not to add WBRT to SRS should depend on whether the patient has a high likelihood of developing DBF. Our study suggests that patients who present with multiple brain lesions may be more likely to benefit from the addition of WBRT because they appear to be more than twice as likely to develop DBF as compared to patients with a single lesion.

Adult↗
PubMed2000

Results of linear accelerator-based stereotactic radiosurgery for recurrent and newly diagnosed acoustic neuromas.

Stereotactic radiosurgery (SRS) is used to treat acoustic neuromas, but additional information is needed to firmly establish its safety and efficacy. We review our experience over 7 years treating 29 consecutive patients with a modified linear accelerator (linac) SRS system. Between August 1989 and October 1995, 29 patients with a median age of 67 years (range 26 to 83) underwent linac SRS treatment. Twenty-five patients had unilateral acoustic neuromas, and four patients with neurofibromatosis type II had bilateral vestibular schwannoma. Eligibility criteria for SRS were recurrent tumors (n = 9), age >65 (n = 16), or patient preference (n = 6). Follow-up magnetic resonance imaging scans were performed on all patients. The most common presenting symptoms were hearing impairment (18 patients) and gait difficulties (17 patients). Ten patients were deaf in the affected ear prior to treatment. Doses to the periphery of the tumor ranged from 800 to 2,400 cGy (median 1, 600 cGy) prescribed to the 50% to 80% isodose line (median 80%). After a median radiographic follow-up of 49 months (range 4 to 110 months), 11 tumors were smaller, 17 were stable, and one had evidence of progression (at 41 months). The 5-year local disease control rate (Kaplan-Meier estimate) was 94%. Acute complications were minimal, with only two patients experiencing nausea and vomiting after the procedure. Long-term complications included new or progressive trigeminal and facial nerve deficits with estimated 5-year incidences of 15% and 32%, respectively. Subjective hearing reduction or loss occurred in 14 (74%) of the 19 patients who had useful hearing prior to treatment. Five patients died from unrelated causes. These results suggest that linac SRS provides excellent short-term tumor control rates. Since there was a high risk of cranial nerve neuropathy, we do not recommend using only computed tomography-based planning and high prescription doses. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 145-151 (2000).

Adult↗
PubMed2000

An immunocytochemical study of mitochondrial manganese-superoxide dismutase in the rat hippocampus after kainate administration.

We examined the immunocytochemical distribution of mitochondrial Mn-superoxide dismutase (SOD-2) in the rat hippocampus after systemic injection of kainic acid (KA), in order to understand SOD-2-responsible antioxidant defense mechanism during the neurodegenerative process. SOD-2 immunostaining was more intense in CA3 pyramidal neurons than in CA1 neurons in the normal hippocampus. The immunoreactivity in region CA1 was reduced without significant neuronal losses within 12 h of KA injection. The CA1 and CA3 neurons lost their immunoreactivity, whereas SOD-2-positive glia-like cells proliferated, mainly throughout the CA1 sector, and had intense immunoreactivity 3 and 7 days after KA injection. This immunocytochemical distribution of SOD-2-positive non-neuronal elements was similar to that of glial fibrillary acidic protein (GFAP) and S-100 protein-positive cells. Activated microglial cells selectively marked with lectin occurred in the areas affected by the KA-induced lesion. Double-labeling immunocytochemistry showed the co-localization of SOD-2-positive non-neuronal cells and GFAP or S-100 protein-like immunoreactivity in the same cells. This suggests that astroglial cells mobilized to synthesize of SOD-2 protein in a response to KA toxicity designed to reduce the oxidative damage.

Animals↗
PubMed2000

Changes of hippocampal Cu/Zn-superoxide dismutase after kainate treatment in the rat.

In order to evaluate the putative role of Cu,Zn-superoxide dismutase (SOD-1) in the antioxidant defense mechanism during the neurodegenerative process, we examined the level of mRNA, the specific activity and immunocytochemical distribution for SOD-1 in the rat hippocampus after systemic injection of kainic acid (KA). Hippocampal SOD-1 mRNA levels were significantly increased by the seizure intensity 3 and 7 days after KA. These enhanced mRNA levels for SOD-1 were consistent with the increased specific activities for SOD-1, suggesting that the superoxide radical generated in neurotoxic lesion, induced SOD-1 mRNA. The CA1 and CA3 neurons lost their SOD-1-like immunoreactivity, whereas SOD-1-positive glia-like cells mainly proliferated throughout the CA1 sector and had an intense immunoreactivity at 3 and 7 days after KA. This immunocytochemical distribution for SOD-1-positive non-neuronal elements was similar to that for glial fibrillary acidic protein (GFAP)-positive cells. Each immunoreactivity for SOD-1-positive non-neuronal cell or GFAP in the layers of CA1 and CA3 disappeared 3 and 7 days after a maximal stage 5 seizure. On the other hand, activated microglial cells as selectively marked with the lectin occurred in the areas affected by KA-induced lesion. Double-labeling immunocytochemical analysis demonstrated the co-localization of SOD-1-positive glia-like cells and reactive astrocytes as labeled by GFAP or S-100 protein immunoreactivity. This finding suggested that the mobilization of astroglial cells for the synthesis of SOD-1 protein is a response to the KA insult designed to decrease the neurotoxicity induced by oxygen-derived free radicals. Therefore, these alterations might reflect the regulatory role of SOD-1 against oxygen-derived free radical-induced neuronal degeneration after systemic KA administration.

Animals↗
PubMed2000

Local control and overall survival in atypical meningioma: a retrospective study.

PURPOSE: To evaluate local control and overall survival after primary surgery for patients with atypical meningiomas. METHODS AND MATERIALS: From the Department of Pathology database, we identified 491 cases of meningioma treated at the Cleveland Clinic Foundation from 1979 through 1995. Thirty-three were diagnosed with atypical meningioma. Eleven of the excluded patients had incomplete records, were lost to follow-up, or received treatment elsewhere. Of the 22 evaluable patients, 15 underwent gross total resection (GTR), 4 had a subtotal resection (STR), and 3 had a resection of unknown extent. Eight patients received radiation therapy (2 after initial resection and 6 after at least one recurrence). The median radiation dose was 5,400 cGy (range 3,500-5,940). The median age at presentation was 55.5 years, the male:female ratio was 14:8, and 19/22 patients had a Karnofsky performance score (KPS) > or =80. The independent variables analyzed for overall survival and local control were gender, KPS (> or =80 vs. < 80), extent of surgery (GTR vs. STR or unknown extent of surgery), and postoperative radiation therapy. RESULTS: Median survival was 10.6 years, with a median follow-up of 5.5 years (range 1.5-14.8). Eight of the 22 patients had local recurrence, including 2/15 with GTR, 3/4 with STR, and all 3 patients who underwent resection of unknown extent. At 10 years, patients with GTR had a higher local control rate than those who had either a STR or a resection of unknown extent (87% vs. 17%; p = 0.02). The 5- and 10-year overall survival rates for the entire group were 91% and 76%, respectively. Patients who had GTR had 5- and 10-year overall survival of 87% and 87%, respectively. Patients with STR or resection of unknown extent had 5- and 10-year overall survival rates of 100% and 75%, respectively. CONCLUSION: In patients with atypical meningiomas, gross total resection is associated with a lower recurrence rate than in subtotal resection.

Analysis of Variance↗
PubMed2000

Prolonged exposure to cigarette smoke blocks the neurotoxicity induced by kainic acid in rats.

We examined the effects of cigarette smoke (CS) on three parameters associated with kainic acid (KA)-induced neurotoxicity: seizure activity, cell loss in the hippocampus, and increased Fos-related antigen (FRA) expression. Animals were exposed to the main stream of CS from 15 Kentucky 2R1F research cigarettes containing 28.6 mg tar and 1.74 mg nicotine per cigarette, for 10 min a day, 6 days per week, for 4 weeks, using an automatic smoking machine. KA administration (10 mg/kg, i.p.) produced robust behavioral convulsions lasting 4-5 h. Pre-exposure to CS significantly reduced the seizures, mortality, and severe loss of cells in regions CA1 and CA3 of the hippocampus after KA administration. Consistently, pre-exposure to CS significantly attenuated the KA-induced increased FRA immunoreactivity in the hippocampus. In contrast, pretreatment with central nicotinic antagonist, mecamylamine (2 or 10 mg/kg, i.p.) blocked the neuroprotective effects mediated by CS in a dose-dependent manner. These results indicate that CS exposure provides neuroprotection against the KA insult via nicotinic receptor activation.

Animals↗
PubMed2000

Grain dust induces IL-8 production from bronchial epithelial cells: effect on neutrophil recruitment.

BACKGROUND: There have been several investigations suggesting an involvement of activated neutrophils in the development of grain dust (GD)-induced occupational asthma. Interleukin-8 in the sputa from GD-induced asthmatic patients increased significantly after the exposure to GD. OBJECTIVE: To confirm IL-8 production from bronchial epithelial cells when exposed to GD, and to evaluate the role of IL-8 on neutrophil recruitment. MATERIALS AND METHOD: We cultured Beas-2B, a bronchial epithelial cell line. To observe GD-induced responses, four different concentrations ranging from 1 to 200 microg/mL of GD were incubated for 24 hours and compared with those without incubation of GD. To evaluate the effect of pro-inflammatory cytokines on IL-8 production and neutrophil chemotaxis, epithelial cells were incubated with peripheral blood mononuclear cell (PBMC) culture supernatant derived from subjects with GD-induced asthma exposed to 10 microg/mL of GD, and then compared with those without addition of PBMC supernatant. The level of released IL-8 in the supernatant was measured by enzyme-linked immunosorbent assay. Neutrophil chemotactic activity of the culture supernatant was determined by modified Boyden chamber method. RESULTS: Interleukin-8 production and neutrophil chemotactic activity from bronchial epithelial cells significantly increased with additions of GD in a dose-dependent manner (P < .05, respectively), and were significantly augmented with additions of PBMC supernatant (P < .05, respectively) at each concentration. Close correlation was noted between neutrophil chemotactic activity and IL-8 level (r = 0.87, P < .05). Compared with the untreated sample, pre-treatment of anti-IL-8 antibody induced a significant suppression (up to 67.2%) of neutrophil chemotactic activity in a dose-dependent manner. CONCLUSION: These results suggest that IL-8 produced from bronchial epithelial cells may be a major cytokine, which induces neutrophil migration into the airways when exposed to GD.

Antibodies↗
PubMed2000

Identification of multiple forms of membrane-associated neutral sphingomyelinase in bovine brain.

Many different stimuli such as bioactive agents and environmental stresses are known to cause the activation of sphingomyelinase (SMase), which hydrolyzes sphingomyelin to generate ceramide as a second messenger playing a key role in differentiation and apoptosis in various cell types. Here we identified multiple forms of the membrane-associated neutral SMase (N-mSMase) activity in bovine brain. They could be classified into two groups according to extracting agents: group T-mSMase, extracted with 0.2% Triton X-100, and group S-mSMase, extracted with 0.5 M (NH(4))(2)SO(4). Group T-mSMase: alpha, beta, gamma, and delta, which were extensively purified from 40,000-g pellets of bovine brain homogenates by 3,150-, 5,275-, 1,665-, and 2,556-fold over the membrane extracts, respectively, by sequential use of several column chromatographies. On the other hand, S-mSMase was eluted as two active peaks of S-mSMase epsilon and zeta in a phenyl-5PW hydrophobic HPLC column and further purified by 1,119- and 976-fold over 40,000-g pellets of the homogenates, respectively. These highly purified N-mSMase enzyme preparations migrated as several bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and showed many different features in biochemical properties such as pH dependence, Mg(2+) requirements, and effects of detergents. Taken together, our data strongly suggest that mammalian brain N-mSMase may exist as multiple forms different in both its chromatographic profiles and biochemical properties.

Ammonium Sulfate↗
PubMed2000

Clinicopathologic study of forty-four histologically pure supratentorial oligodendrogliomas.

Few studies in recent years have specifically focused on pure oligodendroglial neoplasms. We retrospectively reviewed the clinicopathologic features of 44 patients with supratentorial oligodendroglioma diagnosed over a 19-year period (1974 to 1993). The study group consisted of 44 patients (age range, 8 to 69 years; median, 42 years), including 31 males. Thirty-one initially resected tumors (70%) were low grade and 13 (30%) were high grade (anaplastic). Using the St Anne-Mayo criteria for astrocytic tumors, 19 tumors (43%) were grade 2, 17 (39%) were grade 3, and 8 were (18%) grade 4. Histologic features of the tumors at initial resection included prominent nucleoli (N = 18, 41%), vascular proliferation (N = 9, 20%), necrosis (N = 6, 14%), and microcystic degeneration (N = 23, 52%). Nuclear atypia was graded as mild in 22 tumors (50%), moderate in 18 (41%), and marked in four (9%). The highest mitosis counts ranged from 0 to 10 mitotic figures (MF)/10 high-power fields (HPF) (mean, 2.4). Twelve patients (27%) had four or more MF/10 HPF. Initial surgery included gross total resection in 10 patients, subtotal resection in 16 patients, and biopsy in 14 patients. Thirty-one patients received adjuvant radiotherapy and 15 received chemotherapy. MIB-1 labeling indices ranged from 0 to 42.3 (median, 1.2 [low grade tumor median, 0.5; anaplastic tumor median, 6.2]). p53 immunostaining was observed in 18 of 43 stained tumors (41%). Overall, 5- and 10-year survival rates were 71% and 63%, respectively. The entire group had a median follow-up of 5.2 years. Age greater than 45 years (P = .02), mitosis counts of > or =4 MF/10 HPF (P = .0004), and MIB-1 labeling indices <2 (P = .03) were independent predictors of survival (Kaplan-Meier analysis). MIB-1 labeling indices <2 (P = .0009) was an independent predictor of disease-free survival. Low cell density (P = .04) and low histologic grade (P = .03) show trends with regard to being associated with longer survival. In conclusion, older patients (>45 years) or patients with tumors with an increased rate of cell proliferation generally have a worse prognosis. Although tumors of high histologic grade generally have a worse survival, the correlation was not statistically significant.

Adolescent↗
PubMed2000

Clinicopathologic analysis of 124 biopsy-proven peripheral nerve diseases.

We reviewed dinical, histological and ultrastructural findings of 124 cases of sural nerve biopsy specimens to delineate the trends of peripheral nerve diseases in our institute. Eighty-one were men and 43 were women. We categorized them into five groups: specific diagnosis (66 cases, 53.2%), axonal degeneration type (47 cases, 37.9%), demyelinating type (4 cases, 3.2%), mixed axonal degeneration-demyelinating type (6 cases, 4.8%) and normal (1 case, 0.9%). Cases with specific diagnosis included 21 inflammatory demyelinating polyneuropathy (15 chronic inflammatory demyelinating polyradiculoneuropathy, 6 Guillain-Barre disease), 13 hereditary motor and sensory neuropathy (7 Charcot-Marie-Tooth type I, 6 Charcot-Marie-Tooth type II), 10 vasculitis, 6 toxic neuropathy, 4 leprosy, 3 diabetic neuropathy, 2 alcoholic neuropathy, 1 Fabry's disease and other specific diseases (5 cases). In our cases, the proportion of specific diagnoses was higher, while the proportion of demyelinating peripheral neuropathies and normal were lower than those of Western series. The results of this study indicate that 1) a dose clinicopathologic correlation is important to make a precise diagnosis of peripheral nerve biopsy, 2) Biopsy under strict indication may reduce unnecessary histologic examination, 3) There is no difference in disease pattern of peripheral neuropathy between Western people and Koreans.

Adult↗
PubMed2000

Comparison of different reducing agents for enhanced detection of heat-injured Listeria monocytogenes.

The effect of different reducing agents (L-cysteine, Oxyrase, and Enterococcus faecium) and their combinations on the detection of heat-injured (62.8 degrees C, 7.5 min or 10 min) Listeria monocytogenes was examined. The incorporation of L-Cysteine (0.5 g/liter) yielded higher percentage detection than any of the other reducing agents (P < 0.05). The combination of Oxyrase (10 U/ml) and E. faecium (10(3) CFU/ml) synergistically enhanced the detection of L. monocytogenes heat-injured for 10 min at 62.8 degrees C (P < 0.05). Simultaneous addition of L-cysteine (0.5 g/liter) and Oxyrase (10 U/ml) significantly lowered the recovery of heat-injured L. monocytogenes (P < 0.05). Higher activities of Oxyrase (50 U/ml) inhibited the detection of heat-injured L. monocytogenes (P < 0.05). The rates of depletion of relative percentage O2 were in the order: L-cysteine (0.5 g/liter; 6.63%/ min) > Oxyrase (10 U/ml; 5.00%/min) > E. faecium (10(8) CFU/ml; 1.66%/min) > E. faecium (10(3) CFU/ml; 0.20%/min). The final levels of redox potential (Eh) achieved were -110.5 mV, -100 mV, -83.5 mV, and -25 mV for E. faecium (10(8) CFU/ml), L-cysteine, Oxyrase, and E. faecium (10(3) CFU/ml), respectively.

Animals↗
PubMed2000

Conventional radiation therapy for skull base tumors: an overview.

Radiation therapy is an important treatment option for patients with skull base tumors. It has been proven to be effective as primary or adjunctive therapy. Results with conventional radiation treatments have been good to excellent, with limited morbidity. Despite recent advances in neurosurgery and radiation oncology, conventional radiation therapy continues to play a role for some patients. The use of newer technologies such as radiosurgery, three-dimensional conformal therapy, and intensity-modulated radiation therapy should provide equal or better tumor control with decreased morbidity. Future studies should determine the roles of conventional and more innovative radiation approaches.

Cranial Irradiation↗