The homeodomain-leucine zipper ATHB23, a phytochrome B-interacting protein, is important for phytochrome B-mediated red light signaling

Phytochromes are red (R)/far-red (FR) photoreceptors that are central to the regulation of plant growth and development. Although it is well known that photoactivated phytochromes are translocated into the nucleus where they interact with a variety of nuclear proteins and ultimately regulate genome-wide transcription, the mechanisms by which these photoreceptors function are not completely understood. In an effort to enhance our understanding of phytochrome-mediated light signaling networks, we attempted to identify novel proteins interacting with phytochrome B (phyB). Using affinity purification in Arabidopsis phyB overexpressor, coupled with mass spectrometry analysis, 16 proteins that interact with phyB in vivo were identified. Interactions between phyB and six putative phyB-interacting proteins were confirmed by bimolecular fluorescence complementation (BiFC) analysis. Involvement of these proteins in phyB-mediated signaling pathways was also revealed by physiological analysis of the mutants defective in each phyB-interacting protein. We further characterized the athb23 mutant impaired in the homeobox protein 23 (ATHB23) gene. The athb23 mutant displayed altered hypocotyl growth under R light, as well as defects in phyB-dependent seed germination and phyB-mediated cotyledon expansion. Taken together, these results suggest that the ATHB23 transcription factor is a novel component of the phyB-mediated R light signaling pathway.

A case of xanthoma disseminatum: evaluation and monitoring by 18F-fluorodeoxyglucose positron emission tomography/computed tomography

Xanthoma disseminatum (XD) is a rare benign histiocytic disorder with extensive mucocutaneous xanthomas that often involves other sites such as the central nervous system (CNS), respiratory tract and abdominal organs. Evaluation of the extent of disease is important because lesions in critical locations may increase morbidity and mortality. However, there are no well-established tools for the evaluation and monitoring of XD. Here, we report a case of XD in a 21-year-old male patient showing skin, mucous membrane, CNS and internal organ involvement. In this case, (18) F-fluorodeoxyglucose positron emission tomography/computed tomography was useful in detecting the extent of the disease and in estimating the therapeutic response.

Engineering bioactive peptide-based therapeutic molecules

Peptides are increasingly emerging as human therapeutic drugs. By screening very large phage display libraries, novel bioactive peptides that bind to the target of interest with desired biological properties can be identified. Peptides that are obtained in this fashion become the basis for therapeutic molecule development. However, naked peptides are usually not sufficient to be therapeutic molecules by themselves. They need to be chemically modified or conjugated to other molecules to obtain desired physicochemical and in vivo properties. In this chapter, we describe a general methodology of identifying bioactive peptides by biopanning of peptide phage libraries. As an example of therapeutic peptide modifications, we also describe a method for fusing the peptides to the Fc portion of antibody molecule to increase in vivo stability and activity.

Proteins involved in DNA damage response pathways and survival of stage I non-small-cell lung cancer patients

BACKGROUND

Biological complexity leads to significant variation in the survival of patients with stage I non-small-cell lung cancer (NSCLC). DNA damage response (DDR) pathways play a critical role in maintaining genomic stability and in the progression of NSCLC. Therefore, the development of a prognostic biomarker focusing on DDR pathways is an intriguing issue.

PATIENTS AND METHODS

Expression of several proteins (ATM, ATMpS1981, γH2AX, 53BP1, 53BP1pS25, Chk2, Chk2pT68, MDC1, MDC1pS964, BRCA1pS1423, and ERCC1) and overall survival were investigated in 889 pathological stage I NSCLC patients.

RESULTS

Low expression of BRCA1pS1423 or ERCC1 was significantly associated with worse survival in the whole cohort of patients. Analysis performed based on histology revealed that low expression of γH2AX, Chk2pT68, or ERCC1 was a poor prognostic factor in squamous cell carcinoma patients [adjusted hazard ratio (aHR), Cox P: 1.544, 0.012 for γH2AX; 1.624, 0.010 for Chk2pT68; 1.569, 0.011 for ERCC1]. The analysis of the interaction between two proteins showed that this effect was more pronounced in squamous cell carcinoma patients. However, these effects were not detected in adenocarcinoma patients.

CONCLUSIONS

The proteins involved in DDR pathways exhibited differential expression between squamous cell carcinoma and adenocarcinoma and were important determinants of survival in stage I squamous cell carcinoma patients.

Involvement of mast cells in inflammation induced by Trichomonas vaginalis via crosstalk with vaginal epithelial cells

Vaginal epithelial cells (VECs) are thought to function as immune-responsive cells in trichomoniasis, and mast cells have been detected in vaginal smears and the vaginal wall in trichomoniasis. It therefore seemed possible that the VEC-trichomonad reaction might affect the activity of mast cells present in the lamina propria of the vaginal mucosa. In this study, we tested whether culture supernatants of VEC incubated with Trichomonas vaginalis (TCM) could stimulate mast cells. When VECs (MS74) were incubated with live trichomonads, IL-8, IL-6 and MCP-1 expressions increased in the TCM, and mast cells (HMC-1) and human neutrophils migrated more actively towards the TCM. Also, when the TCM was added to mast cells, β-hexosaminidase and cytokines (IL-8 and TNF-α) expressions were increased. Moreover, the culture supernatant of mast cells incubated with TCM (M-TCM) had more increased chemotactic activity for neutrophils than that of TCM. We conclude that inflammatory mediators made by VECs in response to activation by T. vaginalis activate and attract mast cells and then stimulate them to induce neutrophil migration. Our results indicate, for the first time, that VECs play a role in the infiltration of mast cells and neutrophils early in T. vaginalis infection.

Trichomonas vaginalis-induced neutrophil apoptosis causes anti-inflammatory cytokine production by human monocyte-derived macrophages

Neutrophils are the predominant inflammatory cells found in the vaginal discharge of patients with a Trichomonas vaginalis infection. Neutrophils have a shorter life span than other leucocytes. Our previous study indicated that live T. vaginalis alters Mcl-1 expression and caspase-3 activation, thereby inducing apoptosis of human neutrophils. However, it was previously unknown that the apoptotic neutrophils brought about by T. vaginalis can influence vaginal inflammation. Thus, human monocyte-derived macrophages (HMDM) were incubated with T. vaginalis-induced apoptotic neutrophils. Cytokine production and phagocytosis by HMDM were evaluated by ELISA and myeloperoxidase stain, respectively. HMDM showed increased anti-inflammatory cytokine production (IL-10) and decreased levels of pro-inflammatory cytokines, such as TNF-α and IL-6, compared with macrophages alone.

Auxin response factor 2 (ARF2) plays a major role in regulating auxin-mediated leaf longevity

Auxin regulates a variety of physiological and developmental processes in plants. Although auxin acts as a suppressor of leaf senescence, its exact role in this respect has not been clearly defined, aside from circumstantial evidence. It was found here that ARF2 functions in the auxin-mediated control of Arabidopsis leaf longevity, as discovered by screening EMS mutant pools for a delayed leaf senescence phenotype. Two allelic mutations, ore14-1 and 14-2, caused a highly significant delay in all senescence parameters examined, including chlorophyll content, the photochemical efficiency of photosystem II, membrane ion leakage, and the expression of senescence-associated genes. A delay of senescence symptoms was also observed under various senescence-accelerating conditions, where detached leaves were treated with darkness, phytohormones, or oxidative stress. These results indicate that the gene defined by these mutations might be a key regulatory genetic component controlling functional leaf senescence. Map-based cloning of ORE14 revealed that it encodes ARF2, a member of the auxin response factor (ARF) protein family, which modulates early auxin-induced gene expression in plants. The ore14/arf2 mutation also conferred an increased sensitivity to exogenous auxin in hypocotyl growth inhibition, thereby demonstrating that ARF2 is a repressor of auxin signalling. Therefore, the ore14/arf2 lesion appears to cause reduced repression of auxin signalling with increased auxin sensitivity, leading to delayed senescence. Altogether, our data suggest that ARF2 positively regulates leaf senescence in Arabidopsis.

CRY1 inhibits COP1-mediated degradation of BIT1, a MYB transcription factor, to activate blue light-dependent gene expression in Arabidopsis

Cryptochromes (CRY) are one of the two major classes of photoreceptors that perceive light stimuli in the UV-A to blue light region and they are involved in multiple aspects of plant growth and development. However, knowledge regarding their signaling transduction components and mechanisms remains limited. Here, we report that a MYB transcription factor Blue Insensitive Trait 1 (BIT1), plays an important role in controlling blue light responses. Hypocotyl growth responses indicate that BIT1 functions as a positive element in blue light signaling, since BIT1 antisense and knock-out lines show a reduced light response in blue light. BIT1 controls blue light-dependent expression of various genes such as PsbS, a member of the light-harvesting complex gene family. A transactivation assay showed that BIT1 regulates promoter activity of PsbS in a blue light-dependent manner and that it requires CRY1 for activation of the PsbS promoter. BIT1 undergoes degradation in darkness and CRY1 functions to stabilize BIT1 in a blue light-dependent manner. In contrast, COP1 binds to BIT1 and mediates its degradation. We propose that the PsbS promoter is activated in blue light via the blue light-dependent stabilization of BIT1 by CRY1, while in darkness BIT1 is degraded by COP1-mediated proteolysis.

Isolation and partial characterization of a bacteriocin produced by Pediococcus pentosaceus K23-2 isolated from Kimchi

AIMS

Screening and partial characterization of a bacteriocin produced by Pediococcus pentosaceus K23-2 isolated from Kimchi, a traditional Korean fermented vegetable.

METHODS AND RESULTS

A total of 1000 lactic acid bacteria were isolated from various Kimchi samples and screened for the production of bacteriocin. Pediocin K23-2, a bacteriocin produced by the Pediococcus pentosaceus K23-2 strain, showed strong inhibitory activity against Listeria monocytogenes. The bacteriocin activity remained unchanged after 15 min of heat treatment at 121 degrees C or exposure to organic solvents; however, it diminished after treatment with proteolytic enzymes. The bacteriocin was maximally produced at 37 degrees C, when the pH of the culture broth was maintained at 5.0 during the fermentation, although the optimum pH for growth was 7.0. The molecular weight of the bacteriocin was about 5 kDa according to a tricine SDS-PAGE analysis.

CONCLUSIONS

Pediococcus pentosaceus K23-2 isolated from Kimchi produces a bacteriocin, which shares similar characteristics to the Class IIa bacteriocins. The bacteriocin is heat stable and shows wide antimicrobial activity against Gram-positive bacteria, especially L. monocytogenes.

SIGNIFICANCE AND IMPACT OF THE STUDY

Pediocin K23-2 and pediocin K23-2-producing P. pentosaceus K23-2 could potentially be used in the food and feed industries as natural biopreservatives, and for probiotic application to humans or livestock.

Overexpression of a chromatin architecture-controlling AT-hook protein extends leaf longevity and increases the post-harvest storage life of plants

Leaf senescence is the final stage of leaf development and is finely regulated via a complex genetic regulatory network incorporating both developmental and environmental factors. In an effort to identify negative regulators of leaf senescence, we screened activation-tagged Arabidopsis lines for mutants that exhibit a delayed leaf senescence phenotype. One of the mutants (ore7-1D) showed a highly significant delay of leaf senescence in the heterozygous state, leading to at least a twofold increase in leaf longevity. The activated gene (ORE7/ESC) encoded a protein with an AT-hook DNA-binding motif; such proteins are known to co-regulate transcription of genes through modification of chromatin architecture. We showed that ORE7/ESC, in addition to binding to a plant AT-rich DNA fragment, could also modify the chromatin architecture, as illustrated by an altered distribution of a histone-GFP fusion protein in the nucleus of the mutant. Globally altered gene expression, shown by microarray analysis, also indicated that activation of ORE7/ESC results in a younger condition in the mutant leaves. We propose that ectopically expressed ORE7/ESC is negatively regulating leaf senescence and suggest that the resulting chromatin alteration may have a role in controlling leaf longevity. Interestingly, activation of ORE7/ESC also led to a highly extended post-harvest storage life.

Implementation of Enhanced Image from Backscatter X-ray System

Considerable attention has been focused on digital X-ray systems with transmission. However, only a few attempts have been made using X-ray backscatter system. It has difficulty that we have to reconstruct image from a little data in the image processing. Especially, it is necessary that the method correct error of detector effectively. That is the most important thing in the acquisition of X-ray data. In this paper, it is that propose some data processing methods that correct error of detector, and we can recognize that the image reconstruction from a little data is effective.

First Report of Pantoea sp. Induced Soft Rot Disease of Pleurotus eryngii in Korea

The king oyster mushroom, Pleurotus eryngii, has become a popular crop because of its unique flavor and texture and is cultivated in many areas in Korea. In 2003, symptoms of water-soaked lesions and soft rot in the stipes and pileus of cultivated P. eryngii was observed in Jinju, Korea. Diseased tissue was plated on nutrient media. Dominate colonies were yellow, convex, circular with smooth margins, and had a shiny texture. Computer analysis of the data gathered, using the API kit (50CHE, bioMérieux, Marcy-l'Etoile, France), showed that the strain belongs to the Enterobacteriaceae. Although the API system did not give an exact identification, the metabolic profile of the bacterial strain closely resembled the database profile of Pantoea sp. (positive for acid production from the fermentation of d-fructose, d-galactose, d-glucose, d-trehalose, and d-ribose and negative for oxidase, urease, pectate, and thiosulfate). The 16S rDNA sequence of the bacterium was determined (GenBank Accession No. AY530796). When compared with those in GenBank, the bacterium was determined to belong to the Enterobacteriaceae family of the Gammaproteobacteria, and the highest degree of sequence similarity was found to be with Pantoea ananatis strain BD 588 (97.4%) and Pantoea ananatis strain Pna 97-1 (97.3%). In the phylogenetic tree, the bacterium clearly related to the Pantoea lineage, as evidenced by the high bootstrap value. A BLAST search with 16S rDNA sequence of the bacterium supported the API results that the isolate belongs to a species of Pantoea. Pathogenicity tests of this new Pantoea isolate were carried out with bacterial suspensions (approximately 1 × 10⁶ CFU/ml) that were grown for 24 h in Luria-Bertani broth cultures. These were used to inoculate directly on the mycelia of P. eryngii that had been cultivated for 35 days in a plastic bottle. The water and broth were also inoculated to another set of bottles as a control experiment. Inoculated bottles were incubated in a cultivation room at 16 to 17°C with relative humidity between 80 and 95%. Early symptoms of the disease included a dark brown water drop that developed on hypha and primordium of the mushrooms after 5 to 7 days. After 13 days, water-soaked lesions developed on the stipes and pileus, and the normal growth of the mushrooms was inhibited. An offensive odor then developed along with a severe soft rot that was similar to the disease symptoms observed under natural conditions. Mushrooms in control bottles did not develop symptoms. Koch's postulates were fulfilled by isolating bacteria from typical lesions from inoculated mushrooms that were identical to the inoculated strain in colony morphology and biochemical characteristics. Pantoea ananatis was first reported as a pathogen of pineapple fruit causing brown rot (3). Several bacterial diseases, such as brown blotch on cultivated mushrooms by Pseudomonas tolaasii (2) and bacterial soft rot on winter mushroom by Erwinia carotovora subsp. Carotovora, causing severe damage to mushrooms are known (1). However, no Pantoea sp. induced disease of edible mushroom has been previously reported. To our knowledge, this is the first report of soft rot disease on P. eryngii caused by Pantoea sp. References: (1) H. Okamoto et al. Ann. Phytopathol. Soc. Jpn. 65:460. 1999. (2) S. G. Paine. Ann. Appl. Biol. 5:206. 1919. (3) F. B. Serrano. Philipp. J. Sci. 36:271, 1928.

Trichomonas vaginalis promotes apoptosis of human neutrophils by activating caspase-3 and reducing Mcl-1 expression

Neutrophils are the predominant inflammatory cells found in the vaginal discharge of patients with Trichomonas vaginalis infection. However, it is not known whether neutrophil apoptosis is induced by live T. vaginalis. Therefore, we examined whether T. vaginalis can influence neutrophil apoptosis, and also whether caspase-3 and the Bcl-2 family members are involved in the apoptosis. Thus, human neutrophils were incubated with live T. vaginalis and neutrophil apoptosis was evaluated by Giemsa, annexin V-PI, and DiOC6 stainings. The neutrophil apoptosis was significantly higher in those incubated with T. vaginalis than in the control group. When trichomonads were pre-treated with mAb to AP65 (adhesin protein), or when trophozoites were separated from neutrophils using a Transwell chamber, neutrophil apoptosis was significantly reduced. The activation of caspase-3 was evident in neutrophils undergoing spontaneous apoptosis but was markedly enhanced during T. vaginalis-induced apoptosis. Moreover, the inhibition of caspase-3 effectively reduced T. vaginalis-induced apoptosis. Trichomonad-induced apoptosis was also associated with reduced expression of the neutrophil anti-apoptotic protein, Mcl-1. These results indicate that T. vaginalis alters Mcl-1 expression and caspase-3 activation, thereby inducing apoptosis of human neutrophils.

Efficacy of PET/CT in the accurate evaluation of primary colorectal carcinoma

AIM

This study was performed to assess in the accurate evaluation of primary colorectal carcinoma using PET/CT.

METHODS

One hundred patients with primary colorectal carcinoma were evaluated during 2004. All patients underwent PET/CT when their preoperative serum carcinoembryonic antigen was >or=10 ng/mL or when CT showed equivocal findings. The appropriateness of PET/CT-induced changes was noted by subsequent operative findings and follow-up.

RESULTS

PET/CT more detected 15 intra-abdominal metastatic lesions than abdomino-pelvic CT scan. PET/CT showed true negative findings in 13 patients and false positive or negative findings in 10. Due to PET/CT results, management plans were altered in 27 patients; 9 had inter-modality changes, 10 received more extensive surgery, and 8 avoided unnecessary procedures.

CONCLUSIONS

PET/CT altered management plan in 24% of patients with primary colorectal carcinoma in correct direction. These findings suggest that PET/CT should be considered a part of standard work up for preoperative evaluation in a subset of patients with colorectal carcinoma.

Abdominal cavernous Iymphangiomas: CT findings

Two adult patients with histopathologically proved cavernous lymphangiomas and one adult patient with lymphangiomas of strongly presumed cavernous type by cytologic and computed tomographic findings are reported. On computed tomograms, multiple, aggregated, small, and tiny cysts without a solid portion, along the lymphatic channels are characteristic computed tomographic findings for cavernous lymphangiomas.

Preclinical application of radioimmunoguided surgery using anti-carcinoembryonic antigen biparatopic antibody in the colon cancer

Radioimmunoguided surgery (RIGS) has been known as a sophisticated tool to detect micrometastasis intraoperatively. A preclinical model of RIGS was designed to test the possible clinical applicability of the biparatopic antibody in detecting colorectal cancer. The biparatopic antibody was constructed using two anti-carcinoembryonic antigen (CEA)-specific antibodies, T84.66 and PR1A3, reacting against two different epitopes. (125)I-labeled biparatopic antibody was introduced via the principal colonic arteries at the end of operation in 10 operable patients with colon cancer. After 24 h, the radioactivities of the tumors and lymph nodes were counted using the gamma-detecting probe. The radioactivity count was performed ex vivo. The accurate detection in the primary tumors and metastatic lymph nodes were 100 and 88.7% respectively. False-positive detections occurred in 24 of 256 lymph nodes (9.4%), whereas false-negative detections occurred in 5 of them (2%). The most frequent cause of false-positive detection was dissociated radionuclides trapped in the lymphatic tissues. False-negative detections occurred mainly from weak targeting by radiolabeled antibody, probably due to weak expression of tumor CEA. Conclusively, as most detection errors appear to be reduced within 3 days in vivo, the biparatopic antibody can efficiently be applied to the clinical RIGS, thereby facilitating accurate detection and removal of occult cancer foci in colorectal cancer.

Phytochrome-specific type 5 phosphatase controls light signal flux by enhancing phytochrome stability and affinity for a signal transducer

Environmental light information such as quality, intensity, and duration in red (approximately 660 nm) and far-red (approximately 730 nm) wavelengths is perceived by phytochrome photoreceptors in plants, critically influencing almost all developmental strategies from germination to flowering. Phytochromes interconvert between red light-absorbing Pr and biologically functional far-red light-absorbing Pfr forms. To ensure optimal photoresponses in plants, the flux of light signal from Pfr-phytochromes should be tightly controlled. Phytochromes are phosphorylated at specific serine residues. We found that a type 5 protein phosphatase (PAPP5) specifically dephosphorylates biologically active Pfr-phytochromes and enhances phytochrome-mediated photoresponses. Depending on the specific serine residues dephosphorylated by PAPP5, phytochrome stability and affinity for a downstream signal transducer, NDPK2, were enhanced. Thus, phytochrome photoreceptors have developed an elaborate biochemical tuning mechanism for modulating the flux of light signal, employing variable phosphorylation states controlled by phosphorylation and PAPP5-mediated dephosphorylation as a mean to control phytochrome stability and affinity for downstream transducers.

Influence of exposure to electromagnetic field on the cardiovascular system

1 We examined whether extremely low frequency electromagnetic fields (ELF-EMF) affect the basal level of cardiovascular parameters and influence of drugs acting on the sympathetic nervous system. 2 Male rats were exposed to sham control and EMF (60 Hz, 20 G) for 1 (MF-1) or 5 days (MF-5). We evaluated the alterations of blood pressure (BP), pulse pressure (PP), heart rate (HR), and the PR interval, QRS interval and QT interval on the electrocardiogram and dysrhythmic ratio in basal level and dysrhythmia induced by beta-adrenoceptor agonists. 3 In terms of the basal levels, there were no statistically significant differences among control, MF-1 and MF-5 in PR interval, QRS interval, mean BP, HR and PP. However, the QT interval, representing ventricular repolarization, was significantly reduced by MF-1 (P < 0.05). 4 (-)-Dobutamine (beta1-adrenoceptor-selective agonist)-induced tachycardia was significantly suppressed by ELF-EMF exposure in MF-1 for the increase in HR (DeltaHR), the decrease in QRS interval (DeltaQRS) and the decrease in QT (DeltaQT) interval. Adrenaline (nonselective beta-receptor agonist)-induced dysrhythmia was also significantly suppressed by ELF-EMF in MF-1 for the number of missing beats, the dysrhythmic ratio, and the increase in BP and PP. 5 These results indicated that 1-day exposure to ELF-EMF (60 Hz, 20 G) could suppress the increase in HR by affecting ventricular repolarization and may have a down-regulatory effect on responses of the cardiovascular system induced by sympathetic agonists.

Regulation of plasminogen activator inhibitor (PAI)-1 expression in a human trophoblast cell line by glucocorticoid (GC) and transforming growth factor (TGF)-beta

Plasminogen activator inhibitor (PAI)-1 plays a key role in the regulation of fibrinolysis and cellular invasion by virtue of suppression of plasminogen activator function. Excessive production of placental PAI-1 has been associated with aberrant periplacental fibrin deposition in pregnancies complicated by pre-eclampsia (PE) and intrauterine growth restriction (IUGR). In the current study we used HTR-8/SVneo cells and primary cultures of cytotrophoblasts as models for study of PAI-1 regulation by transforming growth factor (TGF)-beta, and dexamethasone (DEX), a synthetic glucocorticoid (GC). ELISA and Northern blotting assays revealed that DEX treatment significantly enhanced TGF-beta effects on PAI-1 protein and mRNA expression in HTR-8/SVneo cells and cytotrophoblasts. These effects were GC-specific in that DEX and cortisol, but not estradiol, progesterone or testosterone, augmented PAI-1 levels in TGF-beta-treated cells. Conversely, DEX and TGF-beta treatment suppressed PAI-2 levels in HTR-8/SVneo cells and did not affect PAI-2 levels in cytotrophoblasts. PAI-1 promoter assays revealed that TGF-beta, but not DEX, enhanced PAI-1 expression in HTR-8/SVneo cells through a transcriptional mechanism. These results suggest that GC and TGF-beta may alter fibrinolytic and invasive properties of trophoblasts through their effects on PAI-1 expression.

Phylogenetic relationships between the six superoxide dismutase proteins (FeSOD) of Trichomonas vaginalis and FeSOD6 genetic diversity

The parasitic protozoan Trichomonas vaginalis is known to contain several types of Fe-containing superoxide dismutase proteins (FeSOD). Using three different methods of phylogenetic analysis, maximum parsimony (MP), neighbor joining (NJ), and maximum likelihood (ML) methods, we examined the phylogenetic relationships among the six FeSOD (FeSOD1-FeSOD6) based on their amino acid sequences. All the analyses consistently suggested that the six proteins formed a monophyletic group implying that they probably be originated from an ancestral protein form through repeated duplication events. Although MP tree was totally unresolved, the NJ and ML trees revealed that FeSOD6 placed the most basal position and thus emerged earlier than the other five gene types during the evolution of T. vaginalis. Phylogenetic relationships among the five remaining proteins were (FeSOD2, FeSOD3), (FeSOD4, (FeSOD1, FeSOD5)) although weakly supported in terms of bootstrapping values. In addition to this, we newly designed two PCR primer specifically amplifying full-length FeSOD6 gene and examined its genetic diversity among 12 T. vaginalis isolates from five countries and three continents. They had the same nucleotide sequences except those of three Korean isolates which showed one to three different nucleotides.

Effects of cloned gene dosage on the response of recombinant CHO cells to hyperosmotic pressure in regard to cell growth and antibody production

The effect of cloned gene dosage on growth and product formation under hyperosmotic conditions has been studied using recombinant Chinese hamster ovary (rCHO) cell lines producing chimeric antibody. Batch cultures of four rCHO cell lines carrying different numbers of antibody gene copies were carried out using the hyperosmolar medium. Depending on cloned gene dosage, hyperosmotic pressure decreased specific growth rate (mu) and increased specific antibody productivity (q(Ab)) to a different degree. The cell line with lower cloned gene dosage displayed more significant enhancement in q(Ab) and less reduction in mu at hyperosmolalities. However, the cell line with higher cloned gene dosage still yielded higher maximum antibody concentration at hyperosmolality up to 469 mOsm/kg. Northern blot analysis showed a positive relationship between immunoglobulin mRNA level per cell and q(Ab), indicating that transcriptional regulation was involved in the response of rCHO cells to hyperosmotic pressure. Cell cycle analysis showed that hyperosmotic pressure induced G(1)-phase arrest, suggesting that the increase of cell population in G(1)-phase may contribute in part to enhanced q(Ab) at hyperosmolality. Taken together, although the cell line with lower cloned gene dosage displayed more significant enhancement in q(Ab) at hyperosmolality, the factor that determined the maximum antibody concentration in hyperosmotic rCHO cell cultures was almost exclusively the gene dosage.

Organolanthanide-catalyzed intramolecular hydroamination/cyclization of amines tethered to 1,2-disubstituted alkenes

[reaction: see text] This contribution reports the organolanthanide-catalyzed intramolecular hydroamination/cyclization of amines tethered to 1,2-disubstituted alkenes to afford the corresponding mono- and disubstituted pyrrolidines and piperidines by using coordinatively unsaturated complexes of the type (eta(5)-Me(5)C(5))(2)LnCH(TMS)(2) (Ln = La, Sm), [Me(2)Si(eta(5)-Me(4)C(5))(2)]NdCH(TMS)(2), [Et(2)Si(eta(5)-Me(4)C(5))(eta(5)-C(5)H(4))]NdCH(TMS)(2), and [Me(2)Si(eta(5)-Me(4)C(5))((t)()BuN)]LnE(TMS)(2) (Ln = Sm, Y, Yb, Lu; E = N, CH) as precatalysts. [Me(2)Si(eta(5)-Me(4)C(5))((t)BuN)]LnE(TMS)(2) mediates intramolecular hydroamination/cyclization of sterically demanding amino-olefins to afford disubstituted pyrrolidines in high diastereoselectivity (trans/cis = 16/1) and in good to excellent yield.

Role of the proteasome in the regulation of fetal fibronectin secretion in human placenta

The goal of the current study was to examine the role of the ubiquitin-proteasome system (UPS), a pathway of intracellular degradation, in the regulation of fetal fibronectin (FFN) expression in human placenta. Primary cultures of cytotrophoblasts (CTs) and placental mesenchymal cells (PMCs) were isolated from human term placentas and were maintained in serum-free medium (SFM) in the presence of inhibitors of proteasome-mediated degradation (e.g., MG132) as well as inhibitors of other proteases. Levels of secreted FFN and interleukin (IL)-8 in culture media were quantitated by enzyme-linked immunosorbent assay (ELISA), and cell viability was assessed by trypan blue exclusion. Intracellular levels of FFN and ubiquinated proteins were measured by Western blotting, and levels of fibronectin mRNA were determined following Northern blotting. We found that proteasome inhibitors (MG132, MG262, and PSI) potently suppressed levels of secreted FFN in cultures of CTs, but they not did affect levels of IL-8. Lysosomal, calpain, and serine protease inhibitors as well as the anti-inflammatory compound sulfasalazine did not markedly affect levels of secreted FFN in CT cultures. Proteasome inhibitors did not compromise cell viability during the initial 16-18 hours of treatment and did not affect intracellular levels of FFN protein or fibronectin mRNA. The efficacy of suppression of FFN in CT culture media by proteasome inhibitors reflected their effects on intracellular accumulation of ubiquinated proteins. By contrast, the presence of proteasome inhibitors did not alter levels of secreted FFN in cultures of PMCs. We conclude that inhibitors of proteasome-mediated degradation potently and specifically suppressed extracellular expression of FFN in CTs through a cell type-specific pathway that did not involve alterations in FFN synthesis. This suggests that accumulation of ubiquinated proteins in the presence of proteasome inhibitors blocks FFN secretion or promotes the extracellular degradation of FFN. This experimental paradigm will be useful for dissecting the role of the UPS in regulating CT function.

Rhinosinusitis in transplant patients

The control of perioperative infection has become more important to increase the success rate of organ transplantation. Thorough examination for occult infection prior to transplantation, careful postoperative monitoring and prompt treatment of infections are required. We reviewed the medical records of 278 patients who received organ transplantation over 4 years and analysed the clinical course of rhinosinusitis during the pre- and post-transplantation period. Thirty-two (11.5%) patients had rhinosinusitis. Nineteen were detected during preoperative examination and 13 were postoperative. Sinus surgery was performed in nine patients before organ transplantation. Ten out of 13 patients who had rhinosinusitis detected after transplantation required sinus surgery and three patients had invasive fungal infections. In the immunocompromised host, the clinical presentation of rhinosinusitis may be subtle, but the subsequent clinical course may be fulminant or even fatal. If the transplant recipient has unexplained fever or any nasal symptom, thorough evaluation with a high index of suspicion and prompt management are required.

Simple and reliable preparation of pentavalent 99Tcm-dimercaptosuccinic acid at alkaline pH without oxygen bubbling

We investigated a simple and reliable method for the preparation of 99Tcm-dimercaptosuccinic acid (99Tcm(V)-DMSA) without the addition of oxygen. The effect of pH, amount of reducing agent, and oxygen addition in the synthesis of 99Tcm(V)-DMSA were evaluated. At pH 9, we obtained a radiochemical yield of 95% +/- 1.2% within 10 min and a high stability until 7 h, with 92% +/- 1.5% radiochemical purity. However, at a pH lower than 9, the radiochemical yield was below 90% within 10 min, and a longer reaction time was needed to obtain a radiochemical yield above 90%. The addition of oxygen did not have an additional effect on the radiochemical yield or its stability at pH 9, whereas it increased the radiochemical yield of 99Tcm-(V)-DMSA at pH 7. It was noted that the smaller the amount of reducing agent used, the higher was the radiochemical yield obtained at pH 7. However, at pH 9, the radiochemical yield was not dependent on the amount of reducing agent. In conclusion, the synthesis of 99Tcm(V)-DMSA was more dependent on the pH of the reaction mixture than on the amount of reducing agent or the addition of oxygen. The adjustment of pH 9 was the easiest and most effective method for the synthesis of 99Tcm(V)-DMSA using a commercial kit for 99Tcm(III)-DMSA.

Effect of iron on the virulence of Trichomonas vaginalis

The role of iron was evaluated with respect to the virulence of Trichomonas vaginalis in mice. Iron-supplemented and iron-depleted Diamond's trypticase-yeast extract-maltose (TYM) media were prepared by adding 360 microM of ferrous sulfate and 100 microM of 2,2'-dipyridyl. Trophozoites cultivated from normal TYM and iron-supplemented TYM media produced subcutaneous abscesses; however, trichomonads grown in an iron-deficient TYM medium failed to produce any pathology. In addition to the increased virulence of trophozoites in mice, iron affects the level of adherence and the cytotoxicity of trichomonads to HeLa cells, which are significantly reduced in trophozoites grown in iron-deficient medium. In conclusion, it is suggested that under iron-depleted conditions such as that induced by 2,2'-dipyridyl the virulence of T. vaginalis is reduced.

Two imported cases of cutaneous larva migrans

Cutaneous larva migrans (CLM) is a rare serpiginous cutaneous eruption caused by accidental penetration and migration in the skin with infective larvae of nematode that normally do not have the human as their host. Although CLM has a worldwide distribution, the infection is most frequent in warmer climates. More recently, they have been increasingly imported from the tropics or subtropics by travelers. We experienced two patients who had pruritic serpiginous linear eruption in their skin for a few weeks after traveling to the endemic areas (Brazil and Thailand, respectively). After the treatment with albendazole, the skin lesions resolved with post-inflammatory hyperpigmentation. We report herein two cases of cutaneous larva migrans successfully treated with albendazole.

NMDA receptor and NO mediate ET-1-induced behavioral and cardiovascular effects in periaqueductal gray matter of rats

Endothelin-1 (ET-1), a novel and potent vasoconstrictor in blood vessel, is known to have some functions in the rat central nervous system (CNS). In order to investigate the central functions of ET-1, ET-1 was administered to the periaqueductal gray area (PAG) of anesthetized rats to induce barrel rolling and increase the arterial blood pressure (ABP). ET-1 had a modulatory effect on central cardiovascular and behavioral control. The selective N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 (3 micromol/kg, i.p.) blocked the ET-1 induced responses, and both the nitric oxide synthase (NOS) inhibitor L-NAME (N-nitro-L-arginine methylester 1 mmol/rat) and the nitric oxide (NO) scavenger hemoglobin (15 nmol/rat) had similar effects in reducing the ET-1 (10 pmol/rat)-induced behavioral changes and ABP elevation. However, NO donor sodium nitroprusside (SNP 10 microg, 1 microg/rat) decreased the ET-1 induced ABP elevation, and recovered the ET-1-induced barrel rolling effect that was reduced by MK-801. These results suggest that ET-1 might have neuromodulatory functions such as ABP elevation and barrel rolling induction in the PAG of the rats via the NMDA receptor and NO.

Pelioid-type hepatocellular carcinoma masquerading as a hepatic hemangioma on technetium-99m red blood cell scintigraphy

Technetium-99m red blood cell (RBC) scintigraphy is a very specific method to differentiate a hemangioma from other hepatic masses. The authors report a case of hepatocellular carcinoma that showed a focal area of increased uptake on Tc-99m RBC SPECT in a 60-year-old man. Dynamic computed tomography and angiography revealed features of both hemangioma and hepatocellular carcinoma. Pathologic examination showed that the portion of the hepatocellular carcinoma that showed increased uptake on Tc-99m RBC scintigraphy had peliosis, which is the likely cause of the radiotracer avidity.

Molecular identification of Paragonimus ohirai and P. westermani from Anhui Province, China

Nucleotide sequences of the internal transcribed spacer 2 (ITS2) region were determined from seven adults of species Paragonimus collected from Jinde and Xiuning Counties, Anhui Province, China. Among these, the nucleotide sequence obtained from one Paragonimus adult (Jinde County) was identical to the ITS2 sequence of P. ohirai previously reported. In order to confirm the result, partial regions of mitochondrial cytochrome C oxidase I (COI) and NADH dehydrogenase 1 (ND1) from the putative P. ohirai sample were further sequenced. They showed a high level of similarity with those of P. ohirai, COI (99.7%) and ND1 (99.5%), supporting the result obtained from the ITS2. In addition to this, we designed P. ohirai- and P. westermani-specific primers (BDW and BD2OH) from ITS2 to identify P. westermani and P. ohirai easily and rapidly. After testing utility of the primers, they were applied to identify seven unidentified Paragonimus samples collected from Jinde and Xiuning Counties, China. All the examined samples showed P. westermani band pattern, and it was reconfirmed by sequencing their ITS2 regions that they are P. westermani. This result indicates that the two newly designed specific primers could be quite helpful for easily identifying P. westermani and P. ohirai, that most of Paragonimus in Jinde and Xiuning Counties consist of P. westermani, and that P. ohirai exists in Jinde County with minority.

Acetazolamide stress brain-perfusion SPECT predicts the need for carotid shunting during carotid endarterectomy

Although carotid shunting is occasionally necessary to prevent cerebral ischemia during carotid endarterectomy, there is no reliable indication for this procedure. The purpose of this study was to evaluate whether acetazolamide stress brain-perfusion SPECT can predict the need for carotid shunting during carotid endarterectomy.

METHODS

Basal and acetazolamide stress brain-perfusion SPECT imaging was performed using a 1-d protocol and 99mTc-ethylcysteinate dimer (ECD) in 75 patients (12 women, 63 men; mean age, 64.8 y) before carotid endarterectomy. The need for carotid shunting during carotid endarterectomy was determined by the development of neurologic deterioration after carotid clamping under regional anesthesia. Regional cerebral blood flow, cerebrovascular reserve, the presence of contralateral carotid stenosis (> or =70%), and clinical risk factors, including age, sex, history of minor stroke or transient ischemic attack, diabetes mellitus, hypertension, and smoking, were assessed with regard to whether they could predict the need for shunting.

RESULTS

Carotid endarterectomy was performed safely without carotid shunting in 61 of 75 patients (81.3%). Carotid shunting was required in 14 patients (18.7%). Seven of 21 patients with a contralateral carotid stenosis, 9 of 41 with a reduced regional cerebral blood flow, and 11 of 30 with a reduced regional cerebrovascular reserve underwent carotid shunting. Patients with a reduced cerebrovascular reserve had a significantly higher number of carotid shunts performed (P < 0.01) than did those with a normal reserve, whereas contralateral carotid stenosis (P = 0.054) showed borderline significance. Reduced cerebral blood flow and clinical risk factors did not predict the need for carotid shunting (P > 0.1). Multiple logistic regression analysis showed that reduced cerebrovascular reserve was the only reliable predictor of the need for carotid shunting (P < 0.01). When a severely reduced cerebrovascular reserve (8/8) or reduced cerebral blood flow and cerebrovascular reserve with contralateral carotid stenosis (6/7) were present, carotid shunting was necessary, with positive and negative predictive values of 91% (10/11) and 94% (60/64), respectively.

CONCLUSION

A reduced cerebrovascular reserve can predict the development of cerebral ischemia during carotid clamping. Acetazolamide stress brain-perfusion SPECT may be useful as a complementary method in determining selective carotid shunting during carotid endarterectomy.

Osmoprotective effect of glycine betaine on foreign protein production in hyperosmotic recombinant chinese hamster ovary cell cultures differs among cell lines

When three recombinant Chinese hamster ovary (rCHO) cell lines, CHO/dhfr-B22-4, CS13-1.00*, and CS13-0.02*, were cultivated in hyperosmolar media resulting from NaCl addition, their specific foreign protein productivity increased with medium osmolality. However, due to a simultaneous suppression of cell growth at elevated osmolality, no enhancement in the maximum foreign protein titer was made in batch cultures. To test the feasibility of using glycine betaine, known as a strong osmoprotective compound, for improved foreign protein production in hyperosmotic rCHO cell cultures, hyperosmotic batch cultures were carried out in the presence of 15 mM glycine betaine. Glycine betaine was found to have a strong osmoprotective effect on all three rCHO cell lines. Inclusion of 15 mM glycine betaine in hyperosmolar medium enabled rCHO cell lines to grow at 557 to 573 mOsm/kg, whereas they could not grow in the absence of glycine betaine. However, effect of glycine betaine inclusion in hyperosmolar medium on foreign protein production differed among rCHO cell lines. CHO/dhfr-B22-4 cells retained enhanced specific human thrombopoietin (hTPO) productivity in the presence of glycine betaine, and thereby the maximum hTPO titer obtained at 573 mOsm/kg was increased by 72% over that obtained in the control culture with physiological osmolality (292 mOsm/kg). On the other hand, enhanced specific antibody productivity of CS13-1.00* and CS13-0.02* at elevated osmolality was decreased significantly in the presence of glycine betaine. As a result, the maximum antibody titer at 557 mOsm/kg was similar to that obtained in the control culture with physiological osmolality. The mRNA contents per cell determined by northern blot hybridization correlated with q in all three rCHO cell lines, indicating that transcriptional regulation is responsible in part for q enhancement at hyperosmolality in the absence as well as the presence of glycine betaine. Taken together, efficacy of the simultaneous use of hyperosmotic pressure and glycine betaine as a means to improve foreign protein production was variable among different rCHO cell lines.

Vancomycin-intermediate Staphylococcus aureus in Korea

Recent reports on some methicillin-resistant Staphylococcus aureus (MRSA) with reduced susceptibility to vancomycin have been a major concern in Korea because of the widespread use of vancomycin due to a high prevalence of MRSA in the country. We describe a 45-year-old man with long-standing pelvic abscess due to MRSA. In spite of vancomycin and teicoplanin treatment for a long period of time, the patient died from MRSA sepsis. The blood culture isolate of MRSA exhibited reduced susceptibility to vancomycin (MIC, 8 microg/ml). This is the first report of a vancomycin-intermediate S. aureus case from Korea.

Squamous cell lung cancer with solitary subungual metastasis

Subungual metastasis resulting from internal malignancies is an extremely rare event. A few cases of subungual metastasis from lung cancer have been reported. However, subungual metastasis arising from lung cancer without any other form of distant metastases has not been reported. The misdiagnosis of a solitary subungual metastases as a benign inflammatory lesion is an important problem as it may cause the misdiagnosis of a lower stage of lung cancer. We may be reporting the first case of a subungual metastasis from lung cancer without any other distant metastases.

Fibrous dysplasia with barely increased uptake on bone scan: a case report

Fibrous dysplasia, in general, appears as an area of markedly increased uptake on bone scintigraphy. Therefore, the possibility of fibrous dysplasia is likely to be excluded when the lesion shows no or slightly increased uptake. The authors report a case of incidentally detected fibrous dysplasia that appeared as slightly increased uptake on bone scintigraphy and was found to harbor a bone infarction along with typical fibrous dysplasia by pathologic examination of a specimen sampled by curettage. Barely increased bone uptake in fibrous dysplasia may be associated with decreased vascularity and osteoblast activity of the lesion as a result of concurrent bone infarction. The authors suggest that not every case of fibrous dysplasia appears as an area of intensely increased uptake on a bone scan. Clinicians should be cautious in interpreting bone scans of radiographically indicated fibrous dysplasia.

Applicability of carcinoembryonic antigen-specific monoclonal antibodies to radioimmunoguided surgery for human colorectal carcinoma

Two carcinoembryonic antigen (CEA)-specific monoclonal antibodies (MAbs), PR1A3 and T84.66, were tested to determine whether they could accurately localize colorectal carcinoma and therefore be applicable in radioimmunoguided surgery (RIGS). Twenty-one tumors by three human colorectal carcinoma cell lines with various levels of CEA expression (KM-12c, C75, and Clone A) were successfully implanted in the intra-abdominal organs of 15 nude mice. The tumors was localized using a portable radioisotope detector (Neoprobe 1000) 48 h after injection of radiolabeled MAbs (10 mCi/mouse) when the precordial counts were <20 per 2 s. Histopathological identification of radiolabeled MAbs were also performed using immunohistochemistry and microautoradiography. Radioactivity counted on a portable radioisotope detector correlated well with that on a gamma counter. The distribution in the blood was significantly greater than in other organs (P < 0.001). Localization indices of the tumor in various organs was from 1.1 to 8.5 in the PR1A3-pretreated mice and 3.0 to 8.6 in the T84.66-pretreated mice. Silver grains and immune staining were distributed in the tumor cells of the PR1A3-pretreated mice, whereas they were in the necrotic debris as well as the tumor cells of the T84.66-pretreated mice. There were significantly more silver grains in the liver in the T84.66-pretreated mice than in the PR1A3-pretreated mice (P = 0.004). The sensitivity and specificity of tumor localization by RIGS were 71.4 and 91.4% in the PR1A3-pretreated mice, whereas they were 60 and 76% in the T84.66-pretreated mice. A study using specific anti-CEA MAbs suggested PR1A3 as an efficient immune probe for RIGS in colorectal carcinoma with a low rate of false-positive detection.

Thermosoftening treatment of the nasotracheal tube before intubation can reduce epistaxis and nasal damage

We evaluated whether a thermosoftening treatment with warm saline of a nasotracheal preformed tube can improve navigability through the nasal passageways and reduce epistaxis and nasal damage. A total of 150 patients were randomly allocated to three groups: Group I (untreated tube group, n = 50), Group II (35 degrees C treated tube group, n = 50), and Group III (45 degrees C treated tube group, n = 50). In Groups II and III, the tubes were softened at 35 +/- 2 degrees C and 45 +/- 2 degrees C with warm saline, respectively. In Group I the tube was prepared at room temperature (25 +/- 2 degrees C). The incidence of epistaxis and nasal damage in Groups II and III was significantly less than that of Group I (P: < 0.05). Despite the more frequent incidence of smooth passage in Group III, no statistical difference was found among the groups. Logistic regression analysis also confirmed that epistaxis was more likely to be reduced when the tube had been thermosoftened (odds ratio = 1.46, 95% confidence interval = 1.02, 2.11). We conclude that simple thermosoftening treatment of the nasotracheal tube with warm saline helps to reduce epistaxis and nasal damage.

IMPLICATIONS

Thermosoftening treatment of a nasotracheal tube with warm saline before intubation can effectively reduce epistaxis and nasal damage. This technique is safe, easy, and suitable for all types of tubes and does not require additional implements.

Osmoprotective effect of glycine betaine on thrombopoietin production in hyperosmotic Chinese hamster ovary cell culture: clonal variations

When 23 recombinant Chinese hamster ovary (rCHO) cell clones were cultivated in hyperosmolar medium resulting from NaCl addition (533 mOsm/kg), their specific thrombopoietin (TPO) productivity (q(TPO)) was increased. However, due to depressed cell growth at elevated osmolality, no enhancement in the maximum TPO titer was made in batch cultures of all 23 clones. To test the feasibility of using glycine betaine, known as a strong osmoprotective compound, for improved TPO production in hyperosmotic rCHO cell cultures, hyperosmotic batch cultures of 23 clones were performed in the presence of 15 mM glycine betaine. Glycine betaine was found to have a strong osmoprotective effect on all 23 clones. Inclusion of 15 mM glycine betaine in hyperosmolar medium enabled 22 clones to grow at 542 mOsm/kg, where most clones could not grow in the absence of glycine betaine, but at a cost of reduced q(TPO). However, the relative decrease in q(TPO) varied significantly among clones. Thus, efficacy of the simultaneous use of hyperosmotic pressure and glycine betaine as a means to improve foreign protein production was variable among clones. Six out of 23 clones displayed more than a 40% increase in the maximum TPO titer in the hyperosmolar medium containing glycine betaine, compared with that in the standard medium with a physiological osmolality. Taken together, the results obtained here emphasize the importance of selection of clones for the successful use of hyperosmotic pressure and glycine betaine as an economical means to improve TPO production.

Pneumocystis carinii pneumonia associated with a rapid reduction of cortisol level in a patient with ectopic ACTH syndrome treated by octreotide and ketoconazole

A case is herein reported of pneumocystis carinii pneumonia in a 60-year-old female patient with ectopic production of ACTH at a position 2 cm superior to her right clavicle, revealed in an octreotide scan. Her extremely high plasma ACTH and cortisol levels (460 pg/ml and 80 microg/dl, respectively) were markedly decreased with the combined treatment of octreotide (300 microg/d) and ketoconazole (600 mg/d). As her serum cortisol concentration decreased, pneumocystis carinii pneumonia occurred on the third day of treatment. A secondary E. coli infection was superimposed and the patient died of disseminated intravascular coagulation and adult respiratory distress syndrome. This case suggests that primary prophylaxis for pneumocystis carinii infection should be initiated before cortisol lowering therapy, especially when the plasma cortisol concentration is excessively high, and that early adjunctive glucocorticoid therapy can reduce the acute mortality in patients with endogenous Cushing's syndrome and Pneumocystis carinii pneumonia. This case study would also like to point out that plasma ACTH and cortisol levels were decreased effectively by the combination of octreotide and ketoconazole in this instance of ectopic ACTH syndrome.

Use of Tc-99m HMPAO leukocyte scans to evaluate bone infection: incremental value of additional SPECT images

PURPOSE

In this study, the diagnostic value of Tc-99m hexamethylpropylene amine oxime (HMPAO) leukocyte scans and the role of additional SPECT in the diagnosis of bone infection were evaluated.

MATERIALS AND METHODS

The Tc-99m HMPAO leukocyte scans of 37 patients with clinically suspected bone infection were reviewed. The patients were divided into two groups according to the presence of orthopedic implants. Early (4 to 6 hours) and delayed (18 to 20 hours) planar images and early SPECT images were obtained. The final diagnosis of infection was made based on the pathologic, bacteriologic, and surgical data and clinical follow-up.

RESULTS

Group 1 (25 patients with orthopedic implants) included 15 true-positive, 1 false-negative, 7 true-negative, and 2 false-positive results. Group 2 (12 patients without orthopedic implants) included 7 true-positive, 1 false-negative, and 4 true-negative results. The overall sensitivity of the Tc-99m HMPAO leukocyte scan with SPECT to detect bone infection was 92%, with a specificity rate of 85%. (Group 1: sensitivity, 94%; specificity, 78%. Group 2: 88% and 100% sensitivity and specificity, respectively.)

CONCLUSION

The Tc-99m HMPAO leukocyte scan is useful in the diagnosis of bone infection, regardless of the presence of orthopedic implants. The additional SPECT images may be helpful to localize the site of infection more accurately.

Hepatic and small bowel mucormycosis after chemotherapy in a patient with acute lymphocytic leukemia

Mucormycosis is a rare but invasive opportunistic fungal infection with increased frequency during chemotherapy-induced neutropenia. The clinical infections due to Mucor include rhinocerebral, pulmonary, cutaneous, gastrointestinal and disseminated diseases. The first two are the most common diseases and all entities are associated with a high mortality rate. Still hepatic involvement of Mucor is rarely reported. We experienced a case of hepatic and small bowel mucormycosis in a 56-year-old woman after induction chemotherapy for B-cell acute lymphocytic leukemia. Initial symptoms were a high fever unresponsive to broad spectrum antibiotics and pain in the left lower abdominal quadrant. It was followed by septic shock, deterioration of icterus and progressively elevated transaminase. An abdominal CT demonstrated multiple hypodense lesions with distinct margins in both lobes of liver and pericolic infiltration at small bowel and ascending colon. Diagnosis was confirmed by biopsy of the liver. The histopathology of the liver showed hyphae with the right-angle branching, typical of mucormycosis. The patient was managed with amphotericin B and operative correction of the perforated part of the small bowel was performed. However, the patient expired due to progressive hepatic failure despite corrective surgery and long-term amphotericin B therapy.

Closing volume influences the postural effect on oxygenation in unilateral lung disease

In normal adults, both blood flow and ventilation are distributed preferentially to the dependent lung zones. In adults with unilateral lung disease, arterial oxygenation improves when they are positioned with their good lung down because of improved matching of ventilation and perfusion. When the closing volume is increased, dependent airways are closed during tidal breathing, so that reduced ventilation-perfusion ratio and hypoxia develops and ventilation is preferentially distributed to the upper lung zones. We undertook an observational study on the effects of lateral recumbency on arterial oxygenation in adult patients with unilateral lung disease and tested the hypothesis that oxygenation in lateral recumbency might be influenced by an increase in closing volume. Arterial blood gases were analyzed in the supine, right and left lateral decubitus positions and the AaPO(2) was calculated in 44 randomly selected patients 49.9 +/- 18.7 yr of age with unilateral pneumonia (23 cases) or pulmonary tuberculosis (21 cases). In 26 patients, individual Pa(O(2)) with the normal lung in the dependent position was higher than that with the diseased lung; the opposite was true for 18 patients. The difference in Pa(O(2)) and AaPO(2) between the two positions was statistically significant in both groups. In 16 patients (10 men and six women 49.2 +/- 18.2 yr of age), we measured closing volume and determined the fractional ventilation to each lung by (133)Xe lung scan in the three positions. In these 16 patients, the difference in Pa(O(2)) between the normal and the diseased lung in the dependent position was related significantly to the difference in the fractional ventilation going to the normal lung between the dependent and the supine position (r = 0.642, p = 0. 007). The latter was related significantly to the % predicted closing volume (CV/VC) (r = -0.597, p = 0.015). This study has shown that closing volume, as well as posture, might be involved in determining oxygenation in lateral recumbency in patients with unilateral lung disease.

Hepatobiliary scintigraphy in the assessment of biliary obstruction after hepatic resection with biliary-enteric anastomosis

We investigated the usefulness of hepatobiliary scintigraphy (HBS) for diagnosing biliary obstruction after curative hepatic resection with biliary-enteric anastomosis. The study population consisted of 54 patients who underwent surgery for benign (n=18) or malignant (n=36) biliary disease. We analysed 68 technetium-99m DISIDA scintigrams which were performed at least 1 month after the surgery (median: 9 months). Final diagnosis was made by operative exploration, other invasive radiological studies or clinical and radiological follow-up for at least 6 months after the surgery. Diagnostic accuracy was analysed according to the pretest likelihood of biliary obstruction. There were two total and 15 segmental biliary obstructions. In patients with symptoms of biliary obstruction and abnormal liver function, HBS always allowed correct diagnosis (two instances of total obstruction, seven of segmental obstruction and seven of non-obstruction). Among the patients with nonspecific symptoms or isolated elevation of serum alkaline phosphatase, HBS diagnosed segmental biliary obstruction in seven of the eight instances, and non-obstruction in 22 of 23 instances. There were no cases of biliary obstruction and no false-positive results of HBS in 21 instances with no clinical signs or symptoms of biliary obstruction. The diagnostic sensitivity and specificity of HBS for biliary obstruction were 94% (16/17) and 97% (50/51), respectively. In conclusion, HBS is a highly accurate modality for the diagnosis of segmental biliary obstruction during long-term follow-up after hepatic resection with biliary-enteric anastomosis.

Cloning of a cysteine proteinase gene from Acanthamoeba culbertsoni

Free living amoeba, including pathogenic Acanthamoeba culbertsoni, are widely distributed in soil and fresh water. It has been found that cysteine proteinases are more active in pathogenic strains of amoeba whereas serine proteinases are found in both pathogenic and nonpathogenic strains. Cysteine proteinases thus play important roles in the pathogenesis of several parasitic infections and have been proposed as targets for the structure-based strategy of drug design. As the first step toward applying this strategy to design inhibitors as antiparasitic agents for A. culbertsoni, we isolated and sequenced the full length clone of a cysteine proteinase gene from A. culbertsoni by performing reverse transcription-polymerase chain reaction (RT-PCR) with degenerate oligonucleotide primers derived from conserved cysteine proteinase sequences. The 5' and the 3' regions of the cysteine proteinase gene were amplified using the PCR protocol for the rapid amplification of cDNA ends (RACE). It has an open reading frame of 1359 bp. The deduced amino acid sequence has the sequence homology with the cysteine proteinase genes of Paragonimus westermani metacercaria, Schistosoma mansoni, human cathepsin L and Fasciola hepatica, each by 45.3%, 45.9%, 57.9% and 50.8% respectively. Sequence analysis and alignment showed significant similarity to other eukaryotic cysteine proteinases, including the conservation of the cysteine, histidine, and asparagine residues that form the catalytic triad. A 1.5 kbp mRNA was detected on Northern blot analysis using full-length cysteine proteinase cDNA as a probe. The A. culbertsoni cysteine proteinase gene (AcCP2) was found to contain Ex3Rx3Wx2N at the proregion and also a proline/threonine-rich C-terminal extension. Therefore, it has cathepsin L-like characteristics. Phylogenetic analysis based on the amino acid sequences of cysteine proteinase indicated that AcCP2 was closely related with papaya, while it was remotely related with those of Schistosoma.

Steroid regulation of human placental integrins: suppression of alpha2 integrin expression in cytotrophoblasts by glucocorticoids

Maintenance of uterine-placental attachment during human pregnancy may depend at least partly on adhesive interactions between cytotrophoblasts and their extracellular matrix (ECM). Such interactions are often mediated by integrins, signal-transducing heterodimeric transmembrane glycoproteins. We previously showed that glucocorticoid (GC) suppressed the expression of collagen and laminin in human placenta; here we show that GC also modulates the expression by human cytotrophoblasts of the integrin subunits alpha2 and beta1, components of a known receptor for these ECM ligands. Cytotrophoblasts were isolated from human term placentas, cultured up to 4 days in the presence of 0-1000 nM dexamethasone (DEX), and assayed for 1) integrin messenger RNA (mRNA) levels by Northern hybridization, 2) integrin subunit synthesis after [35S]methionine labeling, or 3) cell surface integrin levels after 125I labeling by lactoperoxidase. In four independent experiments, 100 nM DEX reduced mRNA levels for integrin alpha2 to 6+/-1% of the control value. This effect was similar between 1-4 days of treatment and was dose dependent between 1-1000 nM DEX. Cortisol treatment (100 nM) inhibited levels of integrin alpha2 mRNA, but 100 nM testosterone, estradiol, and progesterone were less effective, suggesting that this response was specific to GC. In immunoprecipitation studies, treatment of cytotrophoblasts with 100 nM DEX for 2 days reduced the rates of synthesis of the alpha2 integrin subunit as well as its expression on the cell surface to 1-10% of control levels. DEX effects on the beta1 integrin subunit were less dramatic. DEX reduced beta1 mRNA levels to only 69+/-8% of control levels, a smaller reduction compared with effects on alpha2 integrin mRNA. DEX inhibited beta1 protein synthesis and cell surface expression to 60-70% of control levels. In all experiments, DEX had no effect on total protein synthesis. Thus, our results demonstrate that GC treatment specifically and markedly down-regulates expression of alpha2 integrin subunit by human cytotrophoblasts. This finding is consistent with the concept that uterine-placental adherence across gestation may be regulated by coordinate effects on ECM ligands and cellular adhesion receptors.

Total synthesis of sufentanil

Sufentanil, a potent anilidopiperidine analgesic, was synthesized from a simple thiophenylethylamine via six step sequence. The key parts of this synthesis involved an efficient construction of thiophenylethylpiperidone by aminomethano desilylation-cyclization followed by Swern oxidation and a direct regioselective N-nucleophilic spiral epoxide cleavage with aniline promoted by Lewis acids.

Diagnosis of trichomoniasis by polymerase chain reaction

The clinical usefulness of polymerase chain reaction (PCR) for the diagnosis of trichomoniasis was evaluated in comparison with other conventional tests. PCR was used for specific detection of Trichomonas vaginalis by primers based on the repetitive sequence cloned from T. vaginalis (TV-E650). Between June 1996 and August 1997, 426 patients visited the department of obstetrics and gynecology, Hanyang University Kuri Hospital and were examined for trichomoniasis using wet mount examination, Papanicolaou (Pap) smear, culture and PCR. One hundred and seventy-seven patients (group A) visited with the symptoms of vaginal discharge and 249 patients (group B) visited for regular cervical Pap smear with no vaginal symptoms. From group A (n = 177), 3 infections (2.0%) were detected by wet mount, 6 infections (3.3%) by Pap smear and culture, and 17 infections (10.4%) by PCR. From group B (n = 249), 4 patients (1.6%) were found to have T. vaginalis by culture and 6 infections (2.4%) were detected by PCR. Therefore, in both groups, PCR for T. vaginalis showed a higher detection rate compared with conventional wet mount, Pap smear or culture. The detection by PCR was specific for T. vaginalis since no amplification was detected with DNAs from other protozoa and Candida albicans. The sensitivity and specificity of PCR were 100%. This method could detect T. vaginalis in vaginal discharge at a concentration as low as 1 cell per PCR mixture. These results indicate that PCR could be used as a specific and sensitive diagnostic tool for human trichomoniasis.