Chemisorption of oxygen onto activated carbon can enhance the stability of biological perchlorate reduction in fixed bed biofilm reactors

Fixed bed biofilm reactors with granular activated carbon (GAC) or glass beads as support media were used to evaluate the influence of short-term (12h) and long-term (23 days) increases of influent dissolved oxygen (DO) concentrations on biological perchlorate removal. The goal was to evaluate the extent by which chemisorption of oxygen to GAC can enhance the stability of biological perchlorate reduction. Baseline influent concentrations were 50 microg/L of perchlorate, 2 mg/L of acetate as C, and 1mg/L of DO. Perchlorate removal in the glass bead reactor seized immediately after increasing influent DO concentrations from 1 to 4 mg/L since glass beads have no sorptive capacity. In the biologically active carbon (BAC) reactor, chemisorption of oxygen to GAC removed a substantial fraction of the influent DO, and perchlorate removal was maintained during short-term increases of influent DO levels up to 8 mg/L. During long-term exposure to influent DO concentrations of 8.5mg/L, effluent perchlorate and DO concentrations increased slowly. Subsequent exposure of the BAC reactor bed to low DO concentrations partially regenerated the capacity for oxygen chemisorption. Microbial analyses indicated similar microbial communities in both reactors, which confirmed that the differences in reactor performance during dynamic loading conditions could be attributed to the sorptive properties of GAC. Using a sorptive biofilm support medium can enhance biological perchlorate removal under dynamic loading conditions.

The high contrast ratio and fast response time of a liquid crystal display lit by a carbon nanotube field emission backlight unit

We report on the fabrication of a carbon nanotube field emission backlight unit (CNT-BLU) and its application for liquid crystal displays (LCD). The CNT-BLU was operated with locally controllable luminance and impulse-type scanning. The local luminance control, which is based on a very small block size of 1 cm(2), consisted of local dimming and local brightening. This resulted in the contrast ratio of the LCD-TV to be as high as 300 000:1. A fast response time of ∼5.7 ms was also achieved from the LCD-TV lit by CNT-BLU, originating from the impulse-type scanning. In addition, the CNT-BLU showed long-term emission stability and high luminance uniformity.

Neuromyelitis optica with brainstem lesion mistaken for brainstem glioma. Case report

Neuromyelitis optica (NMO) is a severe demyelinating syndrome defined principally by its tendency to affect optic nerves and the spinal cord selectively. Asymptomatic brain lesions have recently become a common finding in NMO, and symptomatic brain lesions do not exclude the diagnosis of this entity. The authors describe the case of a 12-year-old girl suffering from an unusually atypical form of NMO in which a brainstem lesion was mistaken for a brainstem glioma. Brainstem involvement in NMO exhibits variable features on neuroimaging and is confused with brainstem glioma in cases of extensive brainstem involvement in childhood. Careful differential diagnosis and proper treatment are vital for a favorable prognosis.

Effect of backwashing on perchlorate removal in fixed bed biofilm reactors

The influence of backwashing on biological perchlorate reduction was evaluated in two laboratory scale fixed bed biofilm reactors using 1- or 3-mm glass beads as support media. Influent perchlorate concentrations were 50 microg/L and acetate was added as the electron donor at a concentration of 2 mg C/L. Perchlorate removal was evaluated at various influent dissolved oxygen (DO) concentrations. Complete perchlorate removal was achieved with an influent DO concentration of 1mg/L resulting in bulk phase DO concentrations below the detection limit of 0.01 mg/L. The influence of increasing influent DO concentrations for 12 h periods was evaluated before and after individual backwash events. Partial perchlorate removal was achieved with an influent DO concentration of 3.5 mg/L before a strong backwash (bulk phase DO concentrations of approximately 0.2mg/L), while no perchlorate removal was observed after the strong backwash at the same influent DO level (bulk phase DO concentrations of approximately 0.8 mg/L). The immediate effect of backwashing depended on influent DO concentrations. With influent DO concentrations of 1 mg/L, strong backwashing resulted in a brief (<12 h) increase of effluent perchlorate concentrations up to 20 microg/L; more pronounced effects were observed with influent DO concentrations of 3mg/L. Daily weak backwashing had a small and, over time, decreasing negative influence on perchlorate reduction, while daily strong backwashing ultimately resulted in the breakdown of perchlorate removal with influent DO concentrations of 3 mg/L.

Identification of a dysferlin gene mutation in a Korean case with Miyoshi myopathy

Recent genetic and immunohistochemical analyses have shown that Miyoshi myopathy (MM) is caused by a mutation in the DYSF gene, which induces dysfunction of dysferlin. The author described one patient showing characteristic MM phenotype with deficiency of dysferlin on immunohistochemistry. Direct DNA sequencing of whole exons of DYSF gene revealed one homozygous missense mutation (G1165C) on exon 12, which let to an amino acid substitution from the glutamic acid to glutamine at the 389 of the peptide sequence in this patient. This is the first reported case of MM confirmed by immunohistochemical and genetic analyses in Korea.

[Serotonin transporter gene polymorphism in healthy adults and patients with irritable bowel syndrome]

BACKGROUND/AIMS

Serotonin is thought to be an important neurotransmitter in the pathogenesis of irritable bowel syndrome (IBS). It is reported that functional polymorphism in the promotor region of the serotonin transporter gene is related with the subtypes of IBS and shows racial difference. However, a functional relation between polymorphism and IBS is not clear. The aim of this study was to investigate 5-hydroxytryptamine transporter (5-HTT) gene polymorphism in patients with IBS.

METHODS

For fifty-six healthy controls and 33 patients with IBS fulfilling Rome II criteria, 5'-flank promotor region of 5-HTT gene was analyzed by polymerase chain reaction.

RESULTS

The genotypes of healthy controls were S/S (57.1%), S/L (37.5%), and L/L (5.4%). Those of IBS patients were S/S (54.5%), S/L (36.4%), and L/L (9.1%). IBS patients were divided into three groups: diarrhea predominant (n=15; S/S, 40%; S/L, 53.3%; L/L, 6.7%), constipation predominant (n=12; S/S, 75.0%; S/L, 8.3%; L/L, 16.7%), diarrhea-constipation alternating type (n=6; S/S, 50%; S/L, 50%). There was no statistical difference in the 5-HTT gene polymorphism between patients and controls, and according to the subtypes of IBS patients (p=0.135).

CONCLUSIONS

There was no relationship between serotonin transporter gene polymorphism and IBS. However, allele S/S genotype was most prominent genotype in both controls and patients.

Monitoring biofilm detachment under dynamic changes in shear stress using laser-based particle size analysis and mass fractionation

Biofilm detachment under a dynamic change in shear stress was monitored using Focused Beam Reflectance Measurements (FBRM, LASENTEC) and mass fractionation. An annular reactor was used to grow biofilm with glucose as substrate. Changing the rotational speed on the inner cylinder of the annular reactor from 150 RPM to 420 RPM induced a step increase in shear stress. It was observed that the rate of detachment increased rapidly after increasing shear stress and then returned to the previous level. Erosion was the dominant process of detachment under steady state operation, whereas sloughing was dominant following the sudden increase in shear stress. After reaching steady state detachment under high shear conditions, the rotational speed was decreased for a 12-hour period. During this brief period of lower shear, the biofilm adjusted to this new condition. When the shear stress was increased again, another sharp increase in effluent solids concentration was observed. A decrease in density indicates that the biofilm became more vulnerable to shear stress after being subjected to this short period of low shear.

Prolonged jaundice following percutaneous coronary intervention and ticlopidine therapy

Ticlopidine, an adenosine diphosphate receptor blocker, is widely used to prevent subacute stent thrombosis after percutaneous coronary intervention. Along with neutropenia and thrombotic thrombocytopenic purpura, cholestatic hepatitis is one of the most serious potential side-effects of ticlopidine therapy. Four patients with prolonged jaundice after ticlopidine therapy, including one fatal case, are presented. Alternative antithrombotic therapy for subsequent percutaneous coronary intervention is also described. Clopidogrel therapy was found to be safe and effective in two patients with a history of ticlopidine-related cholestatic hepatitis.

Effect of inhibitor of tumor necrosis factor-alpha on experimental otitis media with effusion

Tumor necrosis factor (TNF)-alpha is important in the pathogenesis of otitis media with effusion (OME). The purpose of this study was to determine the effect of TNF-alpha antagonist on the outcome of lipopolysaccharide (LPS)-induced OME in rats. Otitis media was induced by injecting Pseudomonas aeruginosa LPS transtympanically. Another (combination) group was pretreated with TNF-alpha antagonist, soluble TNF receptor type I (sTNF RI), before transtympanic injection of LPS. Saline and phosphate-buffered saline solutions were used as controls. Twelve hours after the transtympanic injection, otoscopic examination and aspiration of middle ear effusion (MEE) were done. The temporal bones in each group were examined histopathologically, and the vascular permeability of the middle ear mucosa was measured by the Evans blue vital dye technique. In the LPS and combination groups, MEE developed in 90% and 0% of ears, respectively. The combination group showed less inflammation, less mucosal thickening, and significantly decreased vascular permeability as compared to the LPS group. Transtympanic administration of sTNF RI appears to suppress the development of LPS-induced OME. This study suggests that TNF-alpha antagonist, along with antibiotics, may have an adjunctive role in the future treatment of MEE.

Effect of tumor necrosis factor-alpha on experimental otitis media with effusion

OBJECTIVES/HYPOTHESIS

Up to the present, many reports have demonstrated that local immune response is associated with maintenance and persistence of effusion in the middle ear cavity. Resulting retention of inflammatory cells and mediators in the middle ear results in ongoing effusion. The purpose of this study was to clarify the role of tumor necrosis factor in experimental otitis media with effusion, which was induced by transtympanic injection of tumor necrosis factor in the rats.

STUDY DESIGN

Four groups were designed in two experiments. The purpose of experiment 1 was to confirm that transtympanic injection of TNF-alpha produces the middle ear effusion. In experiment 2, TNFsolRI was used to evaluate the possibility as an inhibitor in otitis media with effusion.

METHODS

The histopathological changes were observed under light microscope, and the changes in microvascular permeability were examined using Evans blue vital dye technique.

RESULTS

Middle ear effusion was developed in 70% of specimens, and histopathological changes, such as subepithelial edema and marked infiltration of neutrophils, were present in 100% at 24 hours after administration of tumor necrosis factor-alpha through transtympanic approach. Extravasation of Evans blue dye was found in all specimens injected by tumor necrosis factor-alpha, which was qualified using a fluorescence microscope and quantified using a spectrophotometer. These histopathological findings and changes in microvascular permeability were significantly reduced by tumor necrosis factor soluble receptor type I.

CONCLUSIONS

Neutrophil infiltration, subepithelial edema, increased microvascular permeability, and resultant effusion were indirectly proved to be induced by tumor necrosis factor-alpha. We hope that this study may contribute to understanding the role of tumor necrosis factor-alpha in otitis media with effusion and clarifying the future role of tumor necrosis factor soluble receptor type I in preventing otitis media with effusion.

Acquired pendular nystagmus with voluntary inhibition

This report documents a case of voluntary inhibition of acquired pendular nystagmus after head trauma. A 30-year-old male developed oscillopsia and decreased visual acuity, as well as findings of acquired pendular nystagmus with voluntary inhibition after head trauma. The EOG finding was horizontal 18-20 Hz bilateral symmetrical pendular nystagmus in all directions of gaze at near and distant fixation. Nystagmus did not change with 14 Prism Diopter base-out prisms on both eyes, but it was possible to abolish it intentionally. Baclofen and Clonazepam had no effect in improving the patient's symptoms and EOG finding.

Haploinsufficiency of protamine-1 or -2 causes infertility in mice

Protamines are the major DNA-binding proteins in the nucleus of sperm in most vertebrates and package the DNA in a volume less than 5% of a somatic cell nucleus. Many mammals have one protamine, but a few species, including humans and mice, have two. Here we use gene targeting to determine if the second protamine provides redundancy to an essential process, or if both protamines are necessary. We disrupted the coding sequence of one allele of either Prm1 or Prm2 in embryonic stem (ES) cells derived from 129-strain mice, and injected them into blastocysts from C57BL/6-strain mice. Male chimeras produced 129-genotype sperm with disrupted Prm1 or Prm2 alleles, but failed to sire offspring carrying the 129 genome. We also found that a decrease in the amount of either protamine disrupts nuclear formation, processing of protamine-2 and normal sperm function. Our studies show that both protamines are essential and that haploinsufficiency caused by a mutation in one allele of Prm1 or Prm2 prevents genetic transmission of both mutant and wild-type alleles.

Induction of alpha1-acid glycoprotein mRNA by cytokines and differentiation in human colon carcinoma cell

The mRNA for the alpha1-acid glycoprotein (AAG) was expressed not only in hepatoma cells, but also in non-hepatic cancer cells. The expression of the AAG mRNA in HT-29 human colon carcinoma cells is induced by cytokines, IL-6, IL-1, and TNF-alpha, in a manner characteristic of the acute phase response, and the expression of AAG mRNA was up-regulated in differentiated HT-29 cells.

Incidence and characterization of Listeria spp. from foods available in Korea

A total of 410 domestic Korean food samples were analyzed for the presence of Listeria spp. by the conventional U.S. Department of Agriculture protocol, and presumptive strains were identified by morphological, cultural and biochemical tests according to Bergey's manual and confirmed by API-Listeria kit. Among the total 410 food samples, 46 samples (11.2%) were found to be contaminated with Listeria species. Among the 46 strains of Listeria spp. isolates, 8 strains (17.42%) for Listeria monocytogenes, 3 strains (6.5%) for Listeria seeligeri, 33 strains (71.7%) for Listeria innocua, and 2 strains (4.4%) for Listeria welshimeri were identified, respectively. Also, only beef, chicken, pork, frozen foods, and sausage were contaminated with L. monocytogenes, and the other products were free of L. monocytogenes. Of 46 Listeria spp. isolates, L. innocua (71.7%) was the most predominantly isolated in a variety of foods compared to other Listeria spp. An in vitro virulence assay for Listeria spp. using myeloma and hybridoma cells from murine and human sources was performed. The result showed that only L. monocytogenes killed approximately 95 to 100% hybridoma cells after 6 h and the other Listeria species, such as L. innocua, L. seeligeri, and L. welshimeri strains had about 0 to 10% lethal effect on hybridoma cells. Also, an antibiotic susceptibility test showed that Listeria spp. isolates were very susceptible to the antibiotics tested, except for nalidixic acid. Also, serotyping results showed 75% of L. monocytogenes isolates from beef, chicken, and frozen pizza belonged to serotype 1 and 25% from sausage were type 4.

The central conduction time in posterior tibial and pudendal nerve somatosensory evoked potentials

The somatosensory evoked potentials (SEPs), following stimulation of both the posterior tibial nerve (PTSEP) and pudendal nerve (PNSEP), comprise of the lumbar negative, subcortical and cortical potential. These can be used to assess the long somatosensory pathway, including peripheral, intraspinal and intracranial conduction along the entire length. This study aimed to compare the central conduction time between the PTSEP and the PNSEP, and to investigate the relationship between the intraspinal and intracranial conduction time in the SEP pathway. The SEPs following stimulation of the posterior tibial nerve at the ankle and the pudendal nerve at the shaft of the penis were analyzed in 20 normal male subjects. The central conduction of the PNSEP was found to be slower than that of the PTSEP (p <0.05). This difference is due to a delay in conduction rather than that of intracranial conduction.

Altered remodeling of nucleolar machineries in cultured hepatocytes treated with thioacetamide

Thioacetamide (TA) is converted into a hyperacetylating agent which causes hepatic necrosis, regeneration, cirrhosis and cancerous transformation. One of the most characteristic toxicities of TA in rat is observed with a 50 mg/kg per day which induces nucleolar enlargement different from that in regenerating liver. From TA-treated liver, the nucleoli were isolated and characterized for an altered nucleolar signal transduction system. Immunochemistry revealed that the poisoned nucleoli had increased levels of both nucleolus specific proteins (nucleophosmin and nucleolin) and various signal molecules (CK2, Erk1/2, p38, protein kinases A and C, and cyclin A). Using flow cytometry, the nucleoli were found to be in G2-arrested nuclei. Manifestation of the nucleolar enlargement could be readily observed using an ex vivo hepatocyte culture. There were two types of nucleolar enlargement. One was observed in normal hepatocytes with light density of enlarged nucleoli. The other was in TA-treated hepatocytes with dense and compact density of enlarged nucleoli, which contained a 3 to 5-fold higher nudeophosmin content than the control. In vitro induction of nucleolar enlargement with TA was possible. As soon as the hepatocytes anchored on a collagen coat, exogeneous TA (higher than 1 microg/mL) could induce dense and compact nucleoli. However, when an exogeneous drug was added after monolayer formation (1 day), no drug-induced nucleolar enlargement was observed.

Ossifying fibroma arising in the right ethmoid sinus and nasal cavity

Ossifying fibroma, a rare tumor entity, is a well-demarcated benign fibro-osseous tumor composed of bone, fibrous tissue and cementum. It is commonly found in the mandible, but also found in the maxilla and paranasal sinuses. Simple curettage is enough when the fibrous lesions are located in the mandible but a complete en bloc excision is required when these lesions are located in the maxilla and paransal sinuses to relieve symptoms and prevent recurrence. With the advent of sinonasal endoscopy in the mid 1980s, and subsequent advances in surgical techniques, endoscopic management of the fibrous-osseous lesions has become possible. In the current case study, we report a successful endoscopic removal of a huge ossifying fibroma located in the right ethmoid sinus and nasal cavity.

Evidence for basolateral but not apical membrane localization of outwardly rectifying depolarization-induced Cl(-) channel in airway epithelia

The rat primary cultured-airway monolayer had been an excellent model for deciphering the ion channel after nystatin permeabilization of its basolateral or apical membrane (Hwang et al., 1996). After apical membrane permeabilization of rat primary cultured-airway monolayer, 4,4'-diisothiocyanatostilbene-2, 2'-disulfonic acid (DIDS)-sensitive outwardly rectifying depolarization-induced Cl(-) (BORDIC) currents were observed across the basolateral membrane in symmetrical NMG-Cl solution in this study. No significant Cl(-) current induced by the application of voltage clamping was observed across the apical membrane in symmetrical NMG-Cl solution after basolateral membrane permeabilization. The halide permeability sequence for BORDIC current was Br(-) = I(-) > Cl(-). BORDIC current was not affected by basolaterally applied bumetanide (0.5 mm). Basolateral DIDS (0.2 mm) but not apical DIDS inhibited CFTR mediated short-circuit current (I(sc)) in an intact monolayer of rat airway epithelia, a T84 human colonal epithelial cell line, and a Calu-3 human airway epithelial cell line. This is the first report showing that depolarization induced Cl(-) current is present on the basolateral membrane of airway epithelia.

The disappeared disease: tuberculosis of the nasal septum

Recent advances in chemotherapy have reduced the incidence of upper respiratory tract tuberculosis. Tuberculosis of the nose is mainly by secondary infection to pulmonary tuberculosis via contagious, hematogenous or lymphatic routes. Primary infection of the nose is rare but possible when self-cleansing mechanism and lysosomal activity, of the nose is lost. A 45-year-old Korean woman with the chief complaints of nasal obstruction, crusting, and recurrent episodes of epistaxis is presented. Physical examination of the nose revealed friable, easily bleeding masses with crusts on both sides of the septum. The appearance and consistency of the lesions were different from those of nasal polyps. Chest and sinu X-rays revealed no active lesions. Tuberculin skin test was positive and the biopsied specimen proved to be consistent with tuberculosis. Her condition improved after anti-tuberculous medication for about 6 months.

Sporadic inclusion body myositis correlates with increased expression and cross-linking by transglutaminases 1 and 2

Sporadic inclusion body myositis (SIBM) is characterized by vacuolar degeneration of muscle fibers and intrafiber clusters of paired helical filaments with abnormal amyloid deposition. Because of their potential involvement in other degenerative disorders, we have examined the expression of transglutaminases (TGases) in normal and SIBM tissues. We report that at least two different enzymes, the ubiquitous TGase 2 as well as the TGase 1 enzyme, are present in muscle tissues. However, in comparison with normal tissue, the expression of TGases 1 and 2 was increased 2.5- and 4-fold in SIBM, accompanied by about a 20-fold higher total TGase activity. By immunohistochemical staining, in normal muscle, TGase 2 expression was restricted to some endomysial connective tissue elements, whereas TGase 1 and beta-amyloid proteins were not detectable. In SIBM muscle, both TGases 1 and 2 as well as amyloid proteins were brightly expressed and co-localized in the vacuolated muscle fibers, but none of these proteins colocalized with inflammatory cell markers. Next, we isolated high molecular weight insoluble proteins from SIBM muscle tissue and showed that they were cross-linked by about 6 residues/1000 residues of the isopeptide bond. Furthermore, by amino acid sequencing of solubilized tryptic peptides, they contain amyloid and skeletal muscle proteins. Together, these findings suggest that elevated expression of TGases 1 and 2 participate in the formation of insoluble amyloid deposits in SIBM tissue and in this way may contribute to progressive and debilitating muscle disease.

Expression of matrix metalloproteinases in the muscle of patients with inflammatory myopathies

OBJECTIVE

To investigate the role of matrix metalloproteinases (MMPs) in the pathogenesis of inflammatory myopathies and the amyloid formation in sporadic inclusion body myositis (s-IBM).

BACKGROUND

MMPs comprise a family of calcium-dependent zinc endoproteinases induced by cytokines and secreted by inflammatory cells. They enhance T-cell migration or adhesion and degrade components of the extracellular matrix proteins. Some MMPs also have been implicated in the formation of beta-amyloid.

METHODS

We examined the expression of MMPs with single and double immunocytochemistry using antibodies against MMP-2, MMP-3, MMP-7, MMP-9, major histocompatibility complex (MHC) class I, CD8+ cells, macrophage, and beta-amyloid precursor protein (beta-APP) on serial muscle biopsy sections from patients with s-IBM, polymyositis (PM), dermatomyositis (DM), and disease control specimens. The enzyme activity of MMPs was measured by gelatin substrate zymography.

RESULTS

Only the gelatinases, MMP-9 and MMP-2, were expressed in the muscle. In s-IBM and PM, but not the control specimens, MMP-9 and MMP-2 immunostained the non-necrotic and MHC class-I-expressing muscle fibers, and MMP-9, but not MMP-2, immunostained the autoinvasive CD8+ cytotoxic T cells. Zymography in muscle homogenates confirmed the increased MMP-2 and MMP-9 enzymatic activity. MMP-2, but not MMP-9, immunostained the rimmed vacuoles in s-IBM and colocalized with beta-APP, suggesting a possible involvement with the amyloid deposits.

CONCLUSIONS

Because collagen IV is prominent on the muscle membrane, the overexpression of matrix metalloproteinases (MMPs) 2 and 9 on the non-necrotic muscle fibers in polymyositis (PM) and sporadic inclusion body myositis (s-IBM) may facilitate lymphocyte adhesion and enhance T-cell-mediated cytotoxicity by degrading extracellular matrix proteins. The findings may have practical implications in considering therapeutic trials with MMP inhibitors in patients with PM and s-IBM.

The genomic and sequence analysis of rat histone H2B genes

In addition to previously characterized testis-specific and somatic H2B histone genes, two somatic histone H2B genes, hereafter called sH2B-2 and sH2B-3, were isolated from a rat genomic library, genomic organization was determined, and their promoter was sequenced. Like many other H2B genes, sH2B-2 gene was closely linked to H2A gene whereas H3 gene was located upstream of sH2B-3 gene. Deletion and mutation analysis of 5' sequence fused to CAT reporter gene revealed that the interaction between CCAAT and octamer binding factors is important for S-phase-specific activation of sH2B-3 gene.