Search for Boosted Dark Matter in COSINE-100

We search for energetic electron recoil signals induced by boosted dark matter (BDM) from the galactic center using the COSINE-100 array of NaI(Tl) crystal detectors at the Yangyang Underground Laboratory. The signal would be an excess of events with energies above 4 MeV over the well-understood background. Because no excess of events are observed in a 97.7  kg·yr exposure, we set limits on BDM interactions under a variety of hypotheses. Notably, we explored the dark photon parameter space, leading to competitive limits compared to direct dark photon search experiments, particularly for dark photon masses below 4 MeV and considering the invisible decay mode. Furthermore, by comparing our results with a previous BDM search conducted by the Super-Kamionkande experiment, we found that the COSINE-100 detector has advantages in searching for low-mass dark matter. This analysis demonstrates the potential of the COSINE-100 detector to search for MeV electron recoil signals produced by the dark sector particle interactions.

Acceptable compression ratio of full-field digital mammography using JPEG 2000

AIM

To estimate the acceptable compression ratio of full-field digital mammography (FFDM) using the Joint Photographic Experts Group (JPEG) 2000 compression algorithm.

MATERIALS AND METHODS

Eighty cases that included images of 40 masses (20 benign, 20 malignant) and 40 microcalcifications (20 benign, 20 malignant) were collected. The images were compressed to five different lossy ratios: 20:1, 40:1, 60:1, 80:1, and 100:1, and four radiologists independently determined whether the compressed group was distinguishable from the control group. The ratio of the compressed group that was rated indistinguishable from the control group was compared for each reviewer, and the results were analysed for agreements of three or more reviewers.

RESULTS

The ability to distinguish the compressed image from the control group is given as a range across the four reviewers: 0-1.3% (0/80 to 1/80) of the 20:1, 0-2.5% (0/80 to 2/80) of the 40:1, 5-7.5% (4/80 to 6/80) of the 60:1, 10-37.5% (8/80 to 30/80) of the 80:1, and 30-87.5% (24/80 to 70/80) of the 100:1. For three compression groups (20:1, 40:1, and 60:1), three or more reviewers agreed that there was a distinguishable difference for 0/80, 0/80, and 3/80 images, respectively. Thus, the compressed images do not differ significantly from the control group (p>0.05). However, the 80:1 and 100:1 compressed images were different for 9/80 and 29/80 images, respectively, which is significantly different from the control group (p<0.05).

CONCLUSION

The lossy 60:1 compression ratio for FFDM is visually identical to the control image and, therefore, potentially acceptable for primary interpretation.

Circulating osteoprotegerin levels are elevated and correlated with antiphospholipid antibodies in patients with systemic lupus erythematosus

Patients with antiphospholipid syndrome (APS) have an increased risk for the development of thrombotic complications. Recent studies indicate that osteoprotegerin (OPG) acts as an important molecule in the development of vascular diseases. The aim of the present study was to examine the association between serum OPG levels and APS manifestations in patients with SLE. Seventy-nine patients with SLE and ninety-two healthy controls, matched for age and sex, were included in this study. Serum levels of OPG, monocyte chemoattractant protein(MCP)-1 and soluble E-selectin were determined by ELISA. At the time of serum sampling, various clinical and laboratory parameters were assessed. We found that serum levels of OPG were significantly higher in patients with SLE than in healthy controls (1236 ± 82 vs 967 ± 37 pg/mL, P = 0.003). Particularly, serum OPG levels were significantly higher in SLE patients with APS than those without (1615 ± 191 vs 1171 ± 91 pg/mL, P = 0.006). Serum OPG levels correlated with titres of IgG anti-cardiolipin antibody ( P = 0.026) and anti-β2-glycoprotein I antibody ( P < 0.001). Moreover, serum OPG also correlated with serum levels of sE-selectin ( P = 0.002), which is an endothelial cell activation marker, and MCP-1 ( P = 0.003), a well known chemokine implicated in thrombogenesis. Collectively, serum OPG levels were increased in SLE patients with APS and correlated with titres of antiphospholipid antibodies, suggesting that OPG might be linked to the development of APS.

Expression patterns in soybean resistant to Phakopsora pachyrhizi reveal the importance of peroxidases and lipoxygenases

Soybean rust caused by Phakopsora pachyrhizi Sydow is a devastating foliar disease that has spread to most soybean growing regions throughout the world, including the USA. Four independent rust resistance genes, Rpp1-Rpp4, have been identified in soybean that recognize specific isolates of P. pachyrhizi. A suppressive subtraction hybridization (SSH) complementary DNA (cDNA) library was constructed from the soybean accession PI200492, which contains Rpp1, after inoculation with two different isolates of P. pachyrhizi that result in susceptible or immune reactions. Both forward and reverse SSH were performed using cDNA from messenger RNA pooled from 1, 6, 12, 24, and 48 h post-inoculation. A total of 1,728 SSH clones were sequenced and compared to sequences in GenBank for similarity. Microarray analyses were conducted on a custom 7883 soybean-cDNA clone array encompassing all of the soybean-rust SSH clones and expressed sequence tags from four other soybean cDNA libraries. Results of the microarray revealed 558 cDNA clones differentially expressed in the immune reaction. The majority of the upregulated cDNA clones fell into the functional category of defense. In particular, cDNA clones with similarity to peroxidases and lipoxygenases were prevalent. Downregulated cDNA clones included those with similarity to cell-wall-associated protein, such as extensins, proline-rich proteins, and xyloglucan endotransglycosylases.

Stable microwave coaxial cavity plasma system at atmospheric pressure

We present a systematic study of the development of a novel atmospheric microwave plasma system for material processing in the pressure range up to 760 torr and the microwave input power up to 6 kW. Atmospheric microwave plasma was reliably produced and sustained by using a cylindrical resonator with the TM(011) cavity mode. The applicator and the microwave cavity, which is a cylindrical resonator, are carefully designed and optimized with the time dependent finite element Maxwell equation solver. The azimuthal apertures are placed at the maximum magnetic field positions between the cavity and the applicator to maximize the coupling efficiency into the microwave plasma at a resonant frequency of 2.45 GHz. The system consists of a magnetron power supply, a circulator, a directional coupler, a three-stub tuner, a dummy load, a coaxial cavity, and a central cavity. Design and construction of the resonant structures and diagnostics of atmospheric plasma using optical experiments are discussed in various ranges of pressure and microwave input power for different types of gases.

Spatio-temporal analysis of molecular delivery through the blood-brain barrier using focused ultrasound

The deposition of gadolinium through ultrasound-induced blood-brain barrier (BBB) openings in the murine hippocampus was investigated. First, wave propagation simulations through the intact mouse skull revealed minimal beam distortion while thermal deposition simulations, at the same sonication parameters used to induce BBB opening in vivo, revealed temperature increases lower than 0.5 degrees C. The simulation results were validated experimentally in ex vivo skulls (m = 6) and in vitro tissue specimens. Then, in vivo mice (n = 9) were injected with microbubbles (Optison; 25-50 microl) and sonicated (frequency: 1.525 MHz, pressure amplitudes: 0.5-1.1 MPa, burst duration: 20 ms, duty cycle: 20%, durations: 2-4 shots, 30 s per shot, 30 s interval) at the left hippocampus, through intact skin and skull. Sequential, high-resolution, T1-weighted MRI (9.4 Tesla, in-plane resolution: 75 microm, scan time: 45-180 min) with gadolinium (Omniscan; 0.5 ml) injected intraperitoneally revealed a threshold of the BBB opening at 0.67 MPa and BBB closing within 28 h from opening. The contrast-enhancement area and gadolinium deposition path were monitored over time and the influence of vessel density, size and location was determined. Sonicated arteries, or their immediate surroundings, depicted greater contrast enhancement than sonicated homogeneous brain tissue regions. In conclusion, gadolinium was delivered through a transiently opened BBB and contained to a specific brain region (i.e., the hippocampus) using a single-element focused ultrasound transducer. It was also found that the amount of gadolinium deposited in the hippocampal region increased with the acoustic pressure and that the spatial distribution of the BBB opening was determined not only by the ultrasound beam, but also by the vasculature of the targeted brain region.

Taste and odour issues in South Korea's drinking water industry

This paper reviews taste and odour (T&O) issues of South Korea's water industry. For this purpose, an overview of the water supply systems and drinking water standards is presented and some results from citizen surveys for customer satisfaction are included. A case study is presented in which the water intake was shifted from inside a main reservoir to a downstream location due to T&O problems. It is true that the South Korean water industry has long relied on the tolerance of consumers for periodic T&O events. Recently the South Korean water industry has become aware that the T&O problems are at the centre of consumers' concerns and has taken several positive approaches. These include monitoring T&O events using sensory and instrumental methods, installation of a baffled-channel PAC contactor and application of advanced water treatment processes.

Aberration correction by nonlinear beam mixing: generation of a pseudo point sound source

Nonlinear beam mixing with microbubbles was explored to create a pseudo point source for aberration correction of therapeutic ultrasound. A damping coefficient for a bubble driven by a dual frequency sound field was derived by revisiting Prosperetti's linearized damping model. As a result, the overall damping term for dual frequency was obtained by linear summation of two damping terms for each frequency. The numerical simulation based on the bubble model suggests that the most efficient size range to generate a 1 MHz frequency from 4 MHz and 5 MHz sound sources is 2.6 to 3.0 microm. Furthermore, this size range constitutes the primary distribution of a specific ultrasound contrast agent. When a chamber of 0.1% of the diluted agent is sonified by 4 MHz and 5 MHz sound beams with 80 degrees incident angle between them, an approximately 100 Pa, 1 MHz difference frequency signal can be measured approximately 10 cm away. In addition, the received 1 MHz difference frequency signal shows omni-directional characteristics, even though the overlap zone of the two sound beams is on the order of the difference frequency wavelength. Therefore, the induced sound source can be considered as a pseudo point source and is expected to be useful for aberration correction for therapeutic ultrasound.

Suppressive effects of PG201, an ethanol extract from herbs, on collagen-induced arthritis in mice

OBJECTIVE

PG201 has been formulated using 12 herbs known to have anti-inflammatory and protective effects on damaged tissue and bone among other functions. The present study was done in order to assess the therapeutic effects of PG201 in collagen-induced arthritis (CIA) in mice.

METHODS

DBA/1 mice were immunized with bovine type II collagen. After a second collagen immunization, mice were treated with PG201 orally at 10 mg/kg once a day for 18 days. Paws were evaluated macroscopically for redness, swelling and deformities. The levels of TNF-alpha and IL-1beta in the ankle were examined. The severity of arthritis within the knee joints was evaluated by histological assessment of cartilage destruction and pannus formation. Molecular indicators related to CIA pathology were analysed by measuring the serum levels of matrix metalloproteinase 2 (MMP-2), tissue inhibitor of matrix metalloproteinase 2 (TIMP-2) and the anti-inflammatory cytokines interleukin (IL)-4 and IL-10.

RESULTS

Administration of PG201 significantly suppressed the progression of CIA and inhibited the production of TNF-alpha and IL-1beta in the paws. The erosion of cartilage was dramatically reduced in mouse knees after treatment with PG201. In the serum of PG201-treated mice, the level of TIMP-2 and the ratio of TIMP-2 to MMP-2 were significantly elevated, and the level of IL-4, but not of IL-10, was increased.

CONCLUSION

Administration of PG201 has therapeutic effects on CIA. Protection of cartilage was particularly prominent. PG201 is a potential therapy for rheumatoid arthritis.

Overexpression of the thymosin beta-10 gene in human ovarian cancer cells disrupts F-actin stress fiber and leads to apoptosis

To understand the molecular changes during ovarian cancer development, we profiled differentially expressed genes in five paired normal and cancerous ovarian tissues. Among the genes that showed differential expression, thymosin beta-10 expression was decreased in four of five cancer tissues. The decreased level of expression was confirmed by Northern. To investigate the gene's functional role in ovarian cancers, we constructed an adenovirus vector expressing thymosin beta-10 and used it to infect ovarian cancer cell lines PA-I and SKOV3. The infected cells showed disrupted F-actin stress fibers, markedly decreased cell growth, and a high rate of apoptosis. Thus, because loss of thymosin beta-10 expression may contribute to the development of a subset of ovarian cancers, restoration of thymosin beta-10 expression may be a new strategy for ovarian cancer treatment.

Imaging of musculoskeletal fibromatosis

The musculoskeletal fibromatoses comprise a wide range of lesions with a common histopathologic appearance. They can be divided into two major groups: superficial and deep. The superficial fibromatoses are typically small, slow-growing lesions and include palmar fibromatosis, plantar fibromatosis, juvenile aponeurotic fibroma, and infantile digital fibroma. The deep fibromatoses are commonly large, may grow rapidly, and are more aggressive. They include infantile myofibromatosis, fibromatosis colli, extraabdominal desmoid tumor, and aggressive infantile fibromatosis. Radiographs typically reveal a nonspecific soft-tissue mass, and calcification is common only in juvenile aponeurotic fibroma. Advanced imaging (ultrasonography, computed tomography, and magnetic resonance [MR] imaging) demonstrates lesion extent. Involvement of adjacent structures is common, reflecting the infiltrative growth pattern often seen in these lesions. MR imaging may show characteristic features of prominent low to intermediate signal intensity and bands of low signal intensity representing highly collagenized tissue. However, fibromatoses with less collagen and more cellularity may have nonspecific high signal intensity on T2-weighted images. Local recurrence is frequent after surgical resection due to the aggressive lesion growth. It is important for radiologists to recognize the imaging characteristics of musculoskeletal fibromatoses to help guide the often difficult and protracted therapy and management of these lesions.

Purification and properties of Aquifex aeolicus DNA polymerase expressed in Escherichia coli

The gene encoding Aquifex aeolicus (Aae) DNA polymerase was expressed under the control of the trp promoter on a high-copy plasmid, pTRPNS, in Escherichia coli. The expressed enzyme was purified 11-fold with a 13.8% yield and a specific activity of 2268.3 U mg(-1). The optimum pH of the enzyme was 6.8-7.2. The optimal concentrations of KCl and Mg(2+) were 20-30 mM and 4-5 mM, respectively. Aae DNA polymerase contained a double-strand-dependent 3'-->5' proofreading exonuclease activity but lacked any detectable 5'-->3' exonuclease activity.

Characterization of a 20 kDa DNase elicitor from Fusarium solani f. sp. phaseoli and its expression at the onset of induced resistance in Pisum sativum

Summary DNase released from Fusarium solani f. sp. phaseoli (Fsph DNase) has previously been reported to induce pathogenesis-related (PR) genes, phytoalexin accumulation and disease resistance against subsequent challenge with the true pea pathogen, Fusarium solani f. sp. pisi (Fspi). This report is a further analysis of DNase production with probes specific for both the gene and protein. N-terminal analysis of the approximately 20 kDa Fsph DNase protein facilitated both the development of anti-Fsph DNase antiserum and the cloning of the Fsph DNase gene. Utilizing the anti-Fsph DNase antiserum to prepare an affinity column, we demonstrated that the retention and recovery of the DNase activity was associated with this protein. Fsph DNase protein was detectable by Western analysis in both the fungi and plant cytoplasm within 6-8 h following inoculation of the pea endocarp surface. Partially purified DNase detected via catalytic activity began accumulating within pea tissue at 3 h post-inoculation. Enhanced fragmentation of pea DNA occurred within 5 h following treatment of pods with Fsph DNase or inoculations with the two fungi. DNA cleavage within the nuclei of endocarp pea cells was detectable via a TUNEL assay at 3 h post-inoculation. As a result of these findings, we propose that the entrance of Fsph DNase into the pea cell and the signalling of plant defence responses is temporally associated with the damage of host DNA.

Angiomatous skeletal lesions

Vascular lesions involving osseous structures are relatively common neoplasms. We will review the appearance of many musculoskeletal angiomatous lesions using the multimodality approach. Lesions to be discussed include osseous hemangioma, glomus tumor, angiomatosis and associated syndromes (Osler-Weber-Rendu, Klippel-Trenaunay-Weber, and Kasabach-Merritt), Gorham, tumor-induced osteomalacia, and aggressive vascular neoplasms (hemangioendothelioma, hemangiopericytoma, and angiosarcoma).

A comparison of the effects of DNA-damaging agents and biotic elicitors on the induction of plant defense genes, nuclear distortion, and cell death

Pea (Pisum sativum L. cv Alcan) endocarp tissue challenged with an incompatible fungal pathogen, Fusarium solani f. sp. phaseoli or fungal elicitors results in the induction of pathogenesis-related (PR) genes and the accumulation of pisatin, a phytoalexin. Essentially the same response occurs in pea tissue exposed to DNA-specific agents that crosslink or intercalate DNA. In this study, the effects of DNA-damaging agents were assessed relative to the inducible expression of several pea PR genes: phenylalanine ammonia lyase, chalcone synthase, and DRR206. Mitomycin C and actinomycin D mimicked the biotic elicitors in enhancing the expression of all three PR genes. The activities of these PR gene promoters, isolated from different plants, were evaluated heterologously in transgenic tobacco. It is remarkable that beta-glucuronidase expression was induced when plants containing the heterologous phenylalanine ammonia lyase, chalcone synthase, and DRR206 promoter-beta-glucuronidase chimeric reporter genes were treated by DNA-damaging agents. Finally, cytological analyses indicated that many of these agents caused nuclear distortion and collapse of the treated pea cells. Yet we observed that cell death is not necessary for the induction of the PR gene promoters assessed in this study. Based on these observations and previously published results, we propose that DNA damage or the associated alteration of chromatin can signal the transcriptional activation of plant defense genes.

Software development for registration of digital subtraction angiography (DSA) images in uterine fibroid embolization

The ISIS Center at Georgetown University Medical Center has developed a comprehensive program for image-guided procedures in the spine. As part of this program, ISIS has developed a software application known as I-SPINE (ISIS's Spine Procedure Imaging Navigation Engine). I-SPINE is a Windows NT application, which is based on the Analyze/AVM libraries. The software architecture follows the Microsoft Foundation Classes (MFC) single document, multiple view paradigm. This has allowed the developers to add new visualization modules to I-SPINE that aid physicians in procedures outside the spine. One such procedure I-SPINE has been expanded for is uterine fibroid embolization. The idea is that by registering and subtracting post-embolization angiographic images from pre-treatment images the resulting image can be used to quantify the embolization effect on the fibroid circulation and predict the treatment response. The I-SPINE digital subtraction angiography (DSA) module allows the interventional radiologist to open a series of pre and post-embolization DSA images that shows the vascular structures of the uterus and the fibroid or fibroids. From these images, the radiologist selects an appropriate image from each series. The selected images are then hand registered using pixel shifting. Once the images are registered, the pixels are subtracted resulting in an image that shows the embolized arteries that were supplying the fibroids.

Imaging of osteochondroma: variants and complications with radiologic-pathologic correlation

Osteochondroma represents the most common bone tumor and is a developmental lesion rather than a true neoplasm. It constitutes 20%-50% of all benign bone tumors and 10%-15% of all bone tumors. Its radiologic features are often pathognomonic and identically reflect its pathologic appearance. Osteochondromas are composed of cortical and medullary bone with an overlying hyaline cartilage cap and must demonstrate continuity with the underlying parent bone cortex and medullary canal. Osteochondromas may be solitary or multiple, the latter being associated with the autosomal dominant syndrome, hereditary multiple exostoses (HME). Complications associated with osteochondromas are more frequent with HME and include deformity (cosmetic and osseous), fracture, vascular compromise, neurologic sequelae, overlying bursa formation, and malignant transformation. Malignant transformation is seen in 1% of solitary osteochondromas and in 3%-5% of patients with HME. Continued lesion growth and a hyaline cartilage cap greater than 1.5 cm in thickness, after skeletal maturity, suggest malignant transformation. Variants of osteochondroma include subungual exostosis, dysplasia epiphysealis hemimelica, turret and traction exostoses, bizarre parosteal osteochondromatous proliferation, and florid reactive periostitis. Recognition of the radiologic spectrum of appearances of osteochondroma and its variants usually allows prospective diagnosis and differentiation of the numerous potential complications, thus helping guide therapy and improving patient management.

Purification and properties of Thermus filiformis DNA polymerase expressed in Escherichia coli

The gene encoding Thermus filiformis (Tfi) DNA polymerase was expressed under the control of the tac promoter on a high-copy plasmid, pJR, in Escherichia coli. The Tfi DNA polymerase was purified by using heat treatment and DEAE-Sephacel column chromatography. The purified enzyme had a molecular mass of 92 kDa, as estimated by SDS/PAGE. The optimum pH and temperature of the enzyme were 8.4-9.0 and 70-72.5 degrees C respectively. The half-life of the enzyme at 94 degrees C was approx. 40 min. The enzyme was activated by the bivalent cations, Mg(2+) and Mn(2+), and was inhibited by EDTA. The optimal Mg(2+) concentration of the enzyme was 4 mM. The optimal conditions for the PCR reaction were slightly different from those for the enzyme activity except for the optimal Mg(2+) concentration. Low concentrations of KCl had no effect on either the enzymic activity or the PCR amplification. The result of the PCR experiment with the enzyme indicates that Tfi DNA polymerase might be useful in DNA amplification.

Immunostimulated glial cells potentiate glucose deprivation-induced death of cultured rat cerebellar granule cells

The present study investigates whether immunostimulated glial expression of inducible nitric oxide synthase influences the glucose deprivation-induced death of rat cerebellar granule cells (CGC). CGC/glia cocultures were immunostimulated by interferon-gamma (200 U/ml) and lipopolysaccharides (1 microg/ml) and 2 days later were challenged by glucose deprivation. Neurotoxicity was assessed by measuring the release of lactate dehydrogenase. Neither a 2-h glucose deprivation nor a 2-day immunostimulation altered the viability of CGC. A 2-day immunostimulation, however, markedly potentiated the glucose deprivation-induced death of CGC. The increased death of glucose-deprived CGC after immunostimulation was mimicked by the nitric oxide (NO) releasing reagent 3-morpholinosydnonimine (SIN-1) and was partially prevented by the NO synthase (NOS) inhibitor N(G)-nitroarginine. The increased death of glucose-deprived CGC either after immunostimulation or by SIN-1 was not altered by various N-methyl-D-aspartate (NMDA) and non-NMDA receptor antagonists. Because superoxide dismutase and catalase, which remove superoxide anion, decreased the augmented death of glucose-deprived immunostimulated CGC, the reaction of NO with superoxide to form peroxynitrite appears to be implicated in the potentiated neurotoxicity. Our data indicate that immunostimulated glial cells potentiate the death of glucose-deprived neurons in part through the expression of inducible NOS but not through NMDA receptor activation. Potentiation of glucose-deprived CGC death by immunostimulated glial cells may be clinically implicated in the tendency of recurrent ischemic insults to be more severe and fatal than an initial ischemic insult.

Effect of topically applied 0.1% dexamethasone on endothelial healing and aqueous composition during the repair process of rabbit corneal alkali wounds

PURPOSE

The effects of topical dexamethasone on the endothelial healing and the change of aqueous compositions were investigated during the repair process of alkali-wounded rabbit cornea.

METHODS

A central corneal alkali wound was produced by a 60 sec application of a 5.5 mm round filter paper soaked in 1N NaOH onto one eye of each rabbit. The eyes subsequently were treated topically with either 0.1% dexamethasone or a balanced salt solution (BSS) 4 times per day for 8 weeks. Endothelial wound morphometry was performed after alizarin red and trypan blue staining. The concentrations of ascorbic acid, glucose, and the ions, Na+, K+, Ca2+ and Mg2+, were measured in the aqueous humor.

RESULTS

Endothelial healing in control (alkali-wounded but not treated with dexamethasone) corneas showed a biphasic pattern of healing: an initial short-term healing for the first week and then a late long-term healing following the secondary endothelial breakdown. Topical administration of 0.1% dexamethasone deterred endothelial healing during the early period and prevented the secondary endothelial breakdown. However, the total repair process of endothelium was accelerated by the dexamethasone-treatment. Among the various components of the aqueous humor examined, ascorbic acid seemed the most sensitive to change caused by the alkali injury and dexamethasone treatment.

CONCLUSIONS

The present data indicate that dexamethasone may have a therapeutic potential in the management of endothelial healing after corneal alkali injury.

Potentiated glucose deprivation-induced death of astrocytes after induction of iNOS

Astrocytes play an essential role in the maintenance of normal neuronal function. Here we report that pretreatment of interferon-gamma (IFN-gamma) and lipopolysaccharides (LPS) made murine astrocytes highly vulnerable to glucose deprivation-induced death. Neither 12-hr glucose deprivation nor 2-day treatment with IFN-gamma (100 U/ml) and LPS (1 microg/ml) altered the viability of astrocytes. However, significant death of IFN-gamma/LPS-treated astrocytes was observed after 4-hr glucose deprivation. This augmented death was mimicked by the nitric oxide releasing reagent 3-morpholinosydnonimine and was in part prevented by the nitric oxide synthase inhibitor NG-nitroarginine. The data indicate that immunostimulated astrocytes can undergo suicidal death during glucose deprivation through the expression of inducible nitric oxide synthase.

Proliferation-dependent vulnerability of glucose-deprived astrocytes to nitric oxide-induced cytotoxicity

The present study investigated the vulnerability of glucose-deprived astrocytes to nitric oxide (NO)-induced cytotoxicity. Primary murine cortical astrocyte cultures of different ages were deprived of glucose in the presence of the NO-releasing reagent 3-morpholinosydnonimine. Glucose-deprived astrocytes displayed an age-dependent vulnerability to NO cytotoxicity. However, this difference in vulnerability with age was found to be dependent on initial plating density. The augmented deaths of astrocyte cultures were consistent with the [3H]thymidine incorporation pattern. Thus, rapidly dividing astrocytes were much more susceptible to NO cytotoxicity under glucose-deprived conditions. The data indicate that the vulnerability of glucose-deprived astrocytes to NO cytotoxicity depends on the proliferative state rather than age in vitro.

Antitumor activity of the aqueous-alcoholic extracts from unripe cotton ball of Gossypium indicum

The present study investigated the antitumor activity of the aqueous-alcoholic extracts from unripe cotton balls of Gossypium indicum. An Exposure of murine B16 melanoma and L1210 lymphoma cells to the extracts resulted in their severe deaths in time- and concentration-dependent manners. Of the extracts, hydrophilic fractions were most efficacious for the antitumor activity and found to contain certain amounts of catechin and its derivatives. The hydrophilic extract fraction C36B2-8 had approximately 10 times more cytotoxic effects on B12 and L1210 cells than on isolated murine thymocytes. High concentrations (> 150 micrograms/ml) of C 36B3-8 mainly induced necrotic cell death. At low concentrations (< 100 micrograms/ml), however, C 36B3-8 induced not only necrosis but also apoptosis of the two tumor cell lines, which was proved by the TUNEL staining and DNA fragmentation techniques. The data indicate that certain ingredients of the cotton ball extract of G. indicum have an antitumor activity.

Cloning and analysis of the DNA polymerase-encoding gene from Thermus filiformis

The gene encoding Thermus filiformis (Tfi) DNA polymerase was cloned and its nucleotide sequence was determined. The primary structure of Tfi DNA polymerase was deduced from its nucleotide sequence. Tfi DNA polymerase is comprised of 833 amino acid residues and its molecular mass was determined to be 93,890 Da. The deduced amino acid sequence of Tfi DNA polymerase showed a high sequence homology to E. coli DNA polymerase I-like DNA polymerases: 78.5% homology to Taq DNA polymerase, 78.4% to Tca DNA polymerase, and 41.8% to E. coli DNA polymerase I. An extremely high sequence identity was observed in the region containing polymerase activity. The G + C content of the coding region for the Tfi DNA polymerase gene was 68.5%, which was higher than that of the chromosomal DNA (65%). The G + C contents in the first, second, and third positions of the codons used were 71.8%, 40.9%, and 92.7% respectively. Codon usage in Tfi DNA polymerase was heavily biased towards the use of G + C in the third position. Rare codons with U or A as the third base were sometimes used to avoid using GA(A/T) TC and TCGA sequences, as they are recognition sites for the restriction endonucleases TfiI and TaqI.

Identification of a variant estrogen receptor lacking exon 4 and its coexpression with wild-type estrogen receptor in ovarian carcinomas

By means of reverse transcription-PCR we have identified an alternatively spliced mRNA coding for a variant estrogen receptor (ER) that lacks exon 4 (ERDelta4) and is coexpressed with the wild-type ER mRNA in ovarian carcinomas. Furthermore, Western blot analysis revealed the expression of the ERDelta4 protein in normal as well as neoplastic ovarian tissues along with the wild-type ER, although the relative amounts of the wild-type ER and ERDelta4 proteins varied. The trans-activational properties of this variant were studied in ER-negative COS1 cell lines by cotransfection of the ERDelta4 expression vector and a reporter gene containing the estrogen response element. The ERDelta4 protein was not able to activate transcription of a reporter gene. However, it inhibited estrogen-dependent transcriptional activation in a dominant negative fashion when it was cotransfected with the wild-type ER and reporter plasmid. Because it has been shown that ERDelta4 is not able to bind to its response element, the observed inhibitory effect probably occurs through protein-protein interactions. Although several variants of the ER have been described from cancerous cells, none has been identified in ovarian tissues, and ERDelta4 is the only isoform detected in normal tissues. These results may have implications for understanding the physiological role of ERDelta4 in normal cells, because it may affect the function of the wild-type ER, depending on the level of the variant ER protein relative to that of the wild-type ER.

Comparison of p53 gene mutations in paired primary and metastatic gastric tumor tissues

Our previous study revealed that mutations of the p53 gene were detected by cDNA sequencing in one of four (25%) primary gastric tumors and in five of six (83%) gastric cancer cell lines. It was of interest that all five cell lines established from metastatic lesions had p53 gene mutations, while the single cell line established from a primary tumor lacked an abnormality. Thus, the current study was initiated to determine the frequency of p53 mutations in 10 pairs of samples from primary gastric carcinomas and their lymph node metastases, in addition to morphologically normal gastric mucosa. In addition, we correlated the findings with other relevant molecular markers including the metastasis associated nm23-H1 gene and loss of heterozygosity (LOH) using multiple polymorphic markers for chromosome 17p and sequencing the entire open reading frame (ORF) of the p53 gene. Five of ten (50%) patients were constitutionally heterozygous for one or more 17p and/or p53 probes (pYNZ 22, BamHI RFLP; pMct35.1, Mspl RFLP; php53cl, Bg/II RFLP), while none had LOH at the 17p and/or p53. A Bg/II RFLP for analysis of possible nm23-H1 somatic allelic deletion revealed no LOH out of four informative cases. One paired sample demonstrated the substitution of valine for isoleucine at codon 41 (GTT to ATT) in both primary gastric tumor and metastasis. Another metastatic sample demonstrated the substitution of proline for threonine at codon 278 (CCT to C/ACT) in addition to a non-mutated codon, while only the wild-type p53 sequence was present in the paired primary gastric tumor tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Imipramine's selective suppression of an L-type calcium channel in neurons of murine dorsal root ganglia involves G proteins

The whole cell recording technique was used to explore the depressant effect of the tricyclic antidepressant imipramine (IP) on calcium currents of neurons in cultures of murine dorsal root ganglia. The maximal whole cell current (ICa) mediated by the L-type calcium channel declined to 54% of control within 3 min of superfusing neurons with a solution containing 30 microM IP. In contrast, the T-type calcium current was unchanged. The IP-induced reduction of ICa was not associated with a change of the current-voltage relations of ICa. The depressant effect of IP on ICa was greatly reduced if neurons were pretreated with pertussis toxin or dialyzed with an intracellular solution containing guanosine 5'-O-2-thiodiphosphate. In contrast, superfusion of neurons with 5 mM 8-bromo-cyclic-AMP did not alter the effect of IP upon ICa. These data suggest that the selective suppressant effect of IP on the L-type calcium channel involves either an interaction with that region of the channel complex coupled to guanosine nucleotide-binding proteins or with guanosine nucleotide-binding proteins themselves.

Performance analysis of associative memories with nonlinearities in the correlation domain

A matched filter-based architecture for associative memories (MFAMs) has been proposed by many researchers. The correlation from a leg of a matched filter bank, after being altered nonlinearly, weights its corresponding library vector. The weighted vectors are summed and clipped to give an estimate of the library vector closest to the input. We analyze the performance of such architectures for binary and/or bipolar inputs and libraries. Sufficient conditions are derived for the correlation nonlinearity so that the MFAM outputs the correct result. If, for example, N bipolar library vectors are stored, theicorrelation nonlinearity Z(x) = N(x/2) will always result in that library vector closest to the input in the Hamming sense.

A comparison of electro-acupuncture, transcutaneous electrical nerve stimulation and laser photo-biostimulation on pain relief and glucocorticoid excretion. A case report

A clinical case report of the comparative effects of electro-acupuncture, Transcutaneous Electrical Nerve Stimulation (TENS) and laser photo-biostimulation on pain relief and 24-hour urinary excretion of 17-hydroxy-corticosteroids (17-OH-CS) following each biostimulation in a patient with a normal pituitary adrenal axis is presented. The excretion of 17-OH-CS after electro-acupuncture was higher than other modalities of treatments while there was no difference in pain relief among different modalities under this particular condition used in this study.

Electrical stimulation of the celiac plexus for pain relief in chronic pancreatitis. A clinical note

A patient with intractable abdominal pain due to chronic pancreatitis was successfully treated by direct electrical stimulation of the celiac plexus. The details of the procedure are presented. This simple innocuous technique could be of value in treating patients with pain due to chronic pancreatitis who would otherwise have a near normal life expectancy. Also, it can be used in patients suffering from cancer of the pancreas and upper abdominal viscera.

Enhancement of intestinal glucose transport following chronic parathion poisoning

Chronic administration of parathion to male rats stimulated glucose (p less than 0.05) but not calcium (p greater than 0.05) transport in the everted duodenal gut sac preparation. Chronic parathion stimulation was not reduced by concurrent administered of atropine. Acutely applied parathion or paraoxon, its active metabolite, did not increase glucose transport in this preparation.