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1.
Anim Microbiome ; 6(1): 30, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38802977

ABSTRACT

BACKGROUND: Metritis is a prevalent uterine disease that affects the welfare, fertility, and survival of dairy cows. The uterine microbiome from cows that develop metritis and those that remain healthy do not differ from calving until 2 days postpartum, after which there is a dysbiosis of the uterine microbiome characterized by a shift towards opportunistic pathogens such as Fusobacteriota and Bacteroidota. Whether these opportunistic pathogens proliferate and overtake the uterine commensals could be determined by the type of substrates present in the uterus. The objective of this study was to integrate uterine microbiome and metabolome data to advance the understanding of the uterine environment in dairy cows that develop metritis. Holstein cows (n = 104) had uterine fluid collected at calving and at the day of metritis diagnosis. Cows with metritis (n = 52) were paired with cows without metritis (n = 52) based on days after calving. First, the uterine microbiome and metabolome were evaluated individually, and then integrated using network analyses. RESULTS: The uterine microbiome did not differ at calving but differed on the day of metritis diagnosis between cows with and without metritis. The uterine metabolome differed both at calving and on the day of metritis diagnosis between cows that did and did not develop metritis. Omics integration was performed between 6 significant bacteria genera and 153 significant metabolites on the day of metritis diagnosis. Integration was not performed at calving because there were no significant differences in the uterine microbiome. A total of 3 bacteria genera (i.e. Fusobacterium, Porphyromonas, and Bacteroides) were strongly correlated with 49 metabolites on the day of metritis diagnosis. Seven of the significant metabolites at calving were among the 49 metabolites strongly correlated with opportunistic pathogenic bacteria on the day of metritis diagnosis. The main metabolites have been associated with attenuation of biofilm formation by commensal bacteria, opportunistic pathogenic bacteria overgrowth, tissue damage and inflammation, immune evasion, and immune dysregulation. CONCLUSIONS: The data integration presented herein helps advance the understanding of the uterine environment in dairy cows with metritis. The identified metabolites may provide a competitive advantage to the main uterine pathogens Fusobacterium, Porphyromonas and Bacteroides, and may be promising targets for future interventions aiming to reduce opportunistic pathogenic bacteria growth in the uterus.

2.
J Dairy Sci ; 106(11): 8098-8109, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37641346

ABSTRACT

The objective of this study was to identify metabolites associated with metritis and use them for identification of cellular mechanisms affected during transition into lactation. Holstein cows (n = 104) had blood collected in the prepartum period (d -14 ± 6 relative to calving), at calving (d 0), and at the day of metritis diagnosis (d 7 ± 2 after calving). Cows with reddish or brownish, watery, and fetid discharge were diagnosed with metritis (n = 52). Cows with metritis were paired with herdmates without metritis (n = 52) based on days in milk. The metabolome of plasma samples was evaluated using untargeted gas chromatography time-of-flight mass spectrometry. Univariate analyses included t-tests and fold change analyses. Metabolites with false discovery rate adjusted P ≤ 0.10 on t-tests were used for partial least squares discriminant analysis coupled with permutational analysis using 2,000 permutations. Metabolites with false discovery rate adjusted P ≤ 0.10 on t-tests were also used for enriched pathway analyses and identification of cellular processes. Cows that developed metritis had affected cellular processes associated with lower amino acid metabolism in the prepartum period, greater lipolysis, cell death, and oxidative stress at calving and at metritis diagnosis, and greater leukocyte activation at calving, but lower immune cell activation at metritis diagnosis. In summary, cows that developed metritis had plasma metabolomic changes associated with greater lipolysis, oxidative stress, and a dysregulated immune response which may predispose cows to metritis development.

3.
J Dairy Sci ; 106(12): 9244-9259, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37641354

ABSTRACT

The objective was to unravel the peripartum immune and metabolic changes associated with metritis in Holstein cows. Holstein cows (n = 128) had blood collected at -14, 0, 3, and 7 d relative to parturition (DRP). Flow cytometry was used to evaluate blood leukocyte counts, proportions, and activation. Total cells, live cells, single cells, monocytes (CD172α+/CD14+), polymorphonuclears (CD172α+/CD14-/SSChigh), B-cells (CD21+/MHCII+), CD4+ T-cells (CD4+), CD8+ T-cells (CD8+), and γδ T-cells (γδTCR+) were evaluated. Both CD62L and CD11b were used as markers of cell activation. Major histocompatibility complex class II was used as a marker of antigen presentation in monocytes. A Milliplex Bovine Cytokine/Chemokine 08-plex kit was used to evaluate plasma concentrations of IFN-γ, IL-1α, IL-1ß, IL-4, IL-6, IL-8, IL-10, and tumor necrosis factor-α. The body weight (BW) change prepartum was calculated as the difference between calving BW and prepartum BW divided by the number of days between measurements. Plasma fatty acids (FA) were measured at -14 and 0 DRP using untargeted gas chromatography with time-of-flight mass spectrometry. Data were analyzed by ANOVA for repeated measures. Cows that developed metritis (n = 57) had greater prepartum BW, prepartum BW loss, and greater FA concentrations at calving. Plasma FA at calving was positively correlated with IL-1ß. Cows that developed metritis had persistent systemic inflammation, which was demonstrated by greater B-cell activation, greater pro-inflammatory cytokine concentrations, and greater cell damage pre- and postpartum. Postpartum, we observed greater polymorphonuclear cell activation and extravasation but lesser monocytes and CD4+ T-cells activation and extravasation, which suggests postpartum immune tolerance. Greater prepartum adiposity in cows that developed metritis may lead to systemic inflammation pre- and postpartum and immune tolerance postpartum, which may lead to failure to prevent bacterial infection, and development of puerperal metritis.


Subject(s)
Cattle Diseases , Pelvic Inflammatory Disease , Female , Cattle , Animals , CD8-Positive T-Lymphocytes , Gas Chromatography-Mass Spectrometry/veterinary , Postpartum Period , Cytokines , Inflammation/veterinary , Pelvic Inflammatory Disease/veterinary , Lactation
4.
Lett Appl Microbiol ; 73(1): 107-112, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33797771

ABSTRACT

Jogaejeot, seasoned Venerupis philippinarum, is a traditional Korean fermented food, and hepatitis A virus (HAV) can be transmitted through contaminated food, especially bivalve shellfish, causing acute gastroenteritis worldwide. Here, we carried out a phylogenetic analysis to identify and characterize HAV strains in jogaejeot samples associated with hepatitis A (HA) outbreaks in Seoul, South Korea, in 2019. The HAV strains were identified using blast and molecular analysis of the amplified HAV VP1-P2B genome region. The HAV strains identified in the five jogaejeot samples shared at least 99% sequence identity, were all classified as genotype IA and were most closely related to strains that are widespread in East Asia. These results support a link between the consumption of jogaejeot and the HA outbreaks observed in 2019 in Seoul. In addition, they indicate a need for more stringent enforcement of food safety regulations for the shellfish industry, especially against HAV, and the value of widespread vaccination.


Subject(s)
Bivalvia/virology , Disease Outbreaks , Fermented Foods/virology , Hepatitis A virus/classification , Hepatitis A/virology , Phylogeny , Shellfish/virology , Animals , Food Safety , Genotype , Hepatitis A/epidemiology , Hepatitis A/prevention & control , Hepatitis A virus/genetics , Humans , RNA, Viral/genetics , Seoul/epidemiology , Vaccination
5.
J Dairy Sci ; 102(4): 3439-3451, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30799104

ABSTRACT

The objective of this study was to evaluate the effect of pegbovigrastim (PEG) treatment of peripartum Holstein cows on the microbiome found in the vagina postpartum using sequencing of the 16S rRNA gene. A subset of cows was randomly sampled from a larger study where cows had been randomly assigned to 1 of 2 treatments: pegbovigrastim (PEG) or untreated control (CTR). The PEG-treated cows received a subcutaneous injection containing 15 mg of pegbovigrastim 7 d before expected calving and a second injection within 24 h of calving. Vaginal samples from 97 PEG-treated and 98 CTR cows were collected at calving, 7 ± 3, and 35 ± 3 d in milk (0, 7, and 35 DIM). Metritis was diagnosed at 7 ± 3 DIM and purulent vaginal discharge (PVD) at 35 ± 3 DIM. The PEG treatment did not alter the vaginal microbiome. Principal coordinate analysis (PCoA) showed that metritic cows had a dissimilar vaginal microbiome compared with cows that did not develop metritis, particularly at 7 but also at 35 DIM. This difference was characterized by higher relative abundance of Porphyromonas and Bacteroides and a lower relative abundance of Ureaplasma, Ruminococcaceae, and Clostridiales at 7 DIM, and a higher relative abundance of Ureaplasma and a lower relative abundance of Pasteurellaceae at 35 DIM. Based on PCoA, we observed that cows that developed PVD had a dissimilar vaginal microbiome compared with cows that did not develop PVD, particularly at 35 DIM but also at 7 DIM. This difference was characterized by a higher relative abundance of Bacteroides at 7 DIM and higher relative abundance of Fusobacterium and Bacteroides at 35 DIM. Cows that developed metritis and PVD also had higher relative abundance of Fusobacterium and Bacteroides at 0 DIM. Furthermore, the Chao1 and Shannon indices were decreased in metritic cows at 7 DIM and in PVD cows at 7 and 35 DIM. In summary, PEG treatment had no effect on the vaginal microbiome, and uterine disease was associated with major changes in the microbiome found in the vagina postpartum.


Subject(s)
Cattle Diseases/prevention & control , Colony-Stimulating Factors/pharmacology , Endometritis/veterinary , Granulocyte Colony-Stimulating Factor/administration & dosage , Microbiota/drug effects , Recombinant Proteins/administration & dosage , Vagina/microbiology , Animals , Bacteroides , Cattle , Cattle Diseases/microbiology , Endometritis/prevention & control , Female , Granulocyte Colony-Stimulating Factor/pharmacology , Postpartum Period , RNA, Ribosomal, 16S , Random Allocation , Recombinant Proteins/pharmacology , Uterine Diseases
6.
Lett Appl Microbiol ; 62(6): 488-93, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27105128

ABSTRACT

UNLABELLED: The emergence of pathogenic bacterial strains resistant to agrochemicals and the increasing demand for organic foods have led to the discovery of new antibacterial metabolites that can be used either directly or as a lead molecule for development of synthetic bactericides. During the screening of antibacterial fungal cultures, we found that one fungal strain, Aspergillus persii EML-HPB1-11, showed strong in vitro antibacterial activity against Xanthomonas arboricola pv. pruni (Xap) with a minimum inhibitory concentration (MIC) of 10% of fermentation broth filtrate. The active compound was identified as penicillic acid (PA: 3-methoxy-5-methyl-4-oxo-2,5-hexadienoic acid) by mass and NMR spectroscopy. The in vitro antibacterial activity of PA was tested against 12 phytopathogenic bacteria. All of the bacterial pathogens tested were highly inhibited by PA with MIC values of 12·3-111·1 µg ml(-1) . It also effectively suppressed the development of bacterial spot disease in detached peach leaves, showing control values of 82·4 and 94·1% at concentrations of 111·1 and 333·3 µg ml(-1) respectively. This is the first report on the production of PA by A. persii. This study suggests that PA can be used as a lead molecule for development of synthetic bactericides for control of various plant diseases. SIGNIFICANCE AND IMPACT OF THE STUDY: Penicillic acid (PA) produced by the seed-borne fungus Aspergillus persii EML-HPB1-11 showed antibacterial activity against various plant pathogenic bacteria. The compound effectively inhibited the growth of 12 plant pathogenic bacteria and successfully controlled bacterial spot disease on peach leaf. These results suggest that PA can be used as a lead molecule for development of synthetic agrochemicals to control plant bacterial diseases.


Subject(s)
Anti-Bacterial Agents/pharmacology , Aspergillus/metabolism , Biological Control Agents/pharmacology , Penicillic Acid/pharmacology , Xanthomonas/drug effects , Microbial Sensitivity Tests , Plant Diseases/microbiology , Plant Leaves/microbiology , Plants/microbiology , Seeds/microbiology
7.
Neuroscience ; 301: 403-14, 2015 Aug 20.
Article in English | MEDLINE | ID: mdl-26047724

ABSTRACT

While prolonged sleep deprivation (SD) could lead to profound negative health consequences, such as impairments in vital biological functions of immunity and cognition, melatonin possesses powerful ameliorating effects against those harmful insults. Melatonin has strong antioxidant and anti-inflammatory effects that help to restore body's immune and cognitive functions. In this study, we investigated the possible role of melatonin in reversing cognitive dysfunction induced by SD in rats. Our experimental results revealed that sleep-deprived animals exhibited spatial memory impairment in the Morris water maze tasks compared with the control groups. Furthermore, there was an increased glial activation most prominent in the hippocampal region of the SD group compared to the normal control (NC) group. Additionally, markers of oxidative stress such as 4-hydroxynonenal (4-HNE) and 7,8-dihydro-8-oxo-deoxyguanine (8-oxo-dG) were significantly increased, while fragile X-mental retardation protein (FMRP) expression was decreased in the SD group. Interestingly, melatonin treatment normalized these events to control levels following SD. Our data demonstrate that SD induces oxidative stress through glial activation and decreases FMRP expression in the neurons. Furthermore, our results suggest the efficacy of melatonin for the treatment of sleep-related neuronal dysfunction, which occurs in neurological disorders such as Alzheimer's disease and autism.


Subject(s)
Antioxidants/therapeutic use , Fragile X Mental Retardation Protein/metabolism , Melatonin/therapeutic use , Memory Disorders/etiology , Memory Disorders/prevention & control , Sleep Deprivation/complications , 8-Hydroxy-2'-Deoxyguanosine , Aldehydes/metabolism , Animals , Brain/drug effects , Brain/metabolism , Cell Survival/genetics , Cells, Cultured , Cerebral Cortex/cytology , Deoxyguanosine/analogs & derivatives , Deoxyguanosine/metabolism , Disease Models, Animal , Embryo, Mammalian , Fragile X Mental Retardation Protein/genetics , Gene Expression Regulation/drug effects , Gene Expression Regulation/genetics , Male , Maze Learning/drug effects , Neurons/drug effects , Neurons/metabolism , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Rats , Rats, Sprague-Dawley , Rats, Wistar , Reactive Oxygen Species/metabolism
8.
Biosens Bioelectron ; 40(1): 258-64, 2013 Feb 15.
Article in English | MEDLINE | ID: mdl-22883747

ABSTRACT

The gold nanowires array electrode (AuNWsA) was synthesized by two step electrodeposition, which provided well oriented vertically aligned nanowires. The dimensions of the nanowires were determined by scanning electron micrograph and found to be around 1.5 µm in length with 200 nm diameter. Each nanowire was separated by a distance of 2-3 times the diameter of the nanowire itself. The electrochemical performance of the AuNWsA electrode was evaluated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Using these analytical tools, this AuNWsA electrode was shown to have a high effective surface area and excellent electron transfer surfaces compared with flat bare Au electrode. The AuNWsA electrode was then used as an electrochemical biosensor electrode by immobilizing probe DNA and analyzed by CV, EIS and Fourier transform infrared measurements. The results of this analysis suggested that the AuNWsA electrode provides good surfaces for the immobilization and hybridization of DNA. The selectivity of the probe DNA immobilized AuNWsA electrode was tested using non-complementary and one base pair mismatching DNA. The detection limit of the AuNWsA electrode was determined to be 6.78×10(-9) M, which is two times smaller than the bare Au electrode.


Subject(s)
Biosensing Techniques/instrumentation , Conductometry/instrumentation , DNA/genetics , Electrodes , Nanotubes/chemistry , Sequence Analysis, DNA/instrumentation , Equipment Design , Equipment Failure Analysis , Reproducibility of Results , Sensitivity and Specificity
9.
Br J Radiol ; 84(1007): e213-6, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22011825

ABSTRACT

Synovial chondromatosis of the temporomandibular joint is a rare benign joint disorder that has been reported in only a few studies. However, we recently encountered a pathologically proven case of this disorder. This case also showed the typical imaging findings on panoramic radiographs and on CT and MR images. Therefore, we report this case and the imaging and pathological findings.


Subject(s)
Calcinosis/diagnosis , Chondromatosis, Synovial/diagnosis , Magnetic Resonance Imaging , Temporomandibular Joint Disorders/diagnosis , Tomography, X-Ray Computed , Calcinosis/complications , Chondromatosis, Synovial/complications , Chondromatosis, Synovial/pathology , Chondromatosis, Synovial/surgery , Facial Pain/etiology , Facial Pain/surgery , Humans , Male , Middle Aged , Temporomandibular Joint Disorders/pathology , Temporomandibular Joint Disorders/surgery , Treatment Outcome
10.
AJNR Am J Neuroradiol ; 31(3): 559-64, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19875472

ABSTRACT

BACKGROUND AND PURPOSE: MR imaging features of HE have not been fully established. The purpose of this study was to determine the topographic distribution and DWI findings of HE. MATERIALS AND METHODS: We retrospectively evaluated HE MR imaging (n = 11). The topographic distribution of the lesions was evaluated on routine MR imaging, and DWI SI and ADC values were assessed. The ADC value of involved lesions was compared with the noninvolved subcortical WM area by use of the paired t test. RESULTS: MR images demonstrated bilateral diffusion-restrictive lesions in the posterior limb of the IC (n = 6), cerebral cortex (n = 8), CR (n = 7), CS (n = 9), hippocampus (n = 4), and BG (n = 1). The mean ADC value of lesions was 448.82 +/- 92.34 x 10(-6) mm(2)/s compared with the mean ADC value of noninvolved lesions (837.72 +/- 62.14 x 10(-6) mm(2)/s); this difference was statistically significant (P < .000). The lesions showed complete resolution on follow-up DWI for 6 patients. Three patients with cortical involvement of > or = 2 lobes showed partial recovery or death, but most of the other patients with WM involvement or cortical involvement in only 1 lobe experienced complete recovery. CONCLUSIONS: The topographic localization of the lesions was the posterior limb of the IC, cerebral cortex, CR, CS, hippocampus, and BG. Most HE lesions probably correspond to areas of reversible cytotoxic edema as seen on DWI, which can predict the prognosis of HE according to the degree of lesion extent.


Subject(s)
Brain Diseases, Metabolic/metabolism , Brain Diseases, Metabolic/pathology , Diffusion Magnetic Resonance Imaging , Hypoglycemia/metabolism , Hypoglycemia/pathology , Aged , Basal Ganglia/metabolism , Basal Ganglia/pathology , Blood Glucose/metabolism , Brain/metabolism , Brain/pathology , Brain Edema/metabolism , Brain Edema/pathology , Cerebral Cortex/metabolism , Cerebral Cortex/pathology , Female , Hippocampus/metabolism , Hippocampus/pathology , Humans , Internal Capsule/metabolism , Internal Capsule/pathology , Male , Middle Aged , Predictive Value of Tests , Prognosis , Retrospective Studies
11.
Cytotherapy ; 10(7): 759-69, 2008.
Article in English | MEDLINE | ID: mdl-18985482

ABSTRACT

BACKGROUND: To study cell replacement therapy using embryonic stem (ES) cells in mice, avoiding immune rejection and tracing the fate of transplanted cells are important issues. This study was carried out to isolate ES cells ubiquitously expressing enhanced green fluorescent protein (EGFP) and test the survival of these cells in allografts in the cochlea of inbred C57BL/6 mice. METHODS: Putative ES cells were isolated from blastocysts collected from C57BL/6-green mice ubiquitously expressing EGFP. Pluripotency of these cells was tested by expression of stem cell markers and in vitro differentiation of the cells into embryoid bodies. Isolated EGFP-transgenic ES cells were injected into the cochlea of deafened inbred C57BL/6 mice, and survival of transplanted cells was identified in histologic sections of the cochlea. RESULTS: Putative ES cells expressed cellular markers for ES cells, including alkaline phosphatase, Oct-4, Nanog and stage-specific embryonic antigen-1. These cells formed embryoid bodies in suspension cultures. Incorporation of transplanted cells was found at the area of spiral ganglion neurons, auditory nerve fibers reaching the organ of Corti and stria vascularis in the scala media. Grafted cells were also found at the location of inner hair cells underneath the tectorial membrane. DISCUSSION: The isolation of ES cells from the EGFP-transgenic mouse and transplantation into allogeneic inbred mice may be a useful means of studying cell therapy with respect to the ubiquitous and stable expression of EGFP and elimination of graft rejection.


Subject(s)
Alkaline Phosphatase/metabolism , Cell Separation , Cochlea/physiology , Embryonic Stem Cells/physiology , Embryonic Stem Cells/transplantation , Green Fluorescent Proteins/genetics , Animals , Cell Survival/physiology , Cochlea/cytology , Embryonic Stem Cells/cytology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Stem Cell Transplantation
13.
Reproduction ; 129(2): 245-9, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15695619

ABSTRACT

This work was undertaken in order to study the developmental competence of nuclear transfer (NT) into cat embryos using fetal fibroblast and adult skin fibroblast cells as donor nuclei. Oocytes were recovered by mincing the ovaries in Hepes-buffered TCM199 and selecting the cumulus oocyte complexes (COCs) with compact cumulus cell mass and dark color. Homogenous ooplasm was cultured for maturation in TCM199+10% fetal bovine serum (FBS) for 12 h and used as a source of recipient cytoplast for exogenous somatic nuclei. In experiment 1, we evaluated the effect of donor cell type on the reconstruction and development of cloned embryos. Fusion, first cleavage and blastocyst developmental rate were not different between fetal fibroblasts and adult skin cells (71.2 vs 66.8; 71.0 vs 57.6; 4.0 vs 6.1% respectively; P < 0.05). In experiment 2, cloned embryos were surgically transferred into the oviducts of recipient queens. One of the seven recipient queens was delivered naturally of 2 healthy cloned cats and 1 stillborn from fetal fibroblast cells of male origin 65 days after embryo transfer. One of three recipient queens was delivered naturally of 1 healthy cloned cat from adult skin cells of female origin 65 days after embryo transfer. The cloned cats showed genotypes identical to the donor cell lines, indicating that adult somatic cells can be used for feline cloning.


Subject(s)
Cats , Cloning, Organism/methods , Fetus/cytology , Nuclear Transfer Techniques , Oocytes , Skin/cytology , Animals , Animals, Newborn , Embryo Transfer/veterinary , Embryonic Development , Female , Fertilization in Vitro , Fibroblasts , Male , Microsatellite Repeats , Pregnancy , Pregnancy, Animal
14.
J Am Chem Soc ; 123(43): 10658-67, 2001 Oct 31.
Article in English | MEDLINE | ID: mdl-11673997

ABSTRACT

Two-photon absorption (TPA) cross sections of four representative series of octupolar molecules are theoretically investigated. The general structure--TPA-property relationship is described by using the effective four-state valence-bond three-charge-transfer model. As the charge-transfer character of the ground electronic state increases due to the strong donors or acceptors, (i) the transition dipole matrix elements between the ground and 2-fold degenerate excited states increase, (ii) the energy gap decreases, and consequently (iii) the TPA transition amplitude monotonically increases. Thus, the design strategy to maximize the TPA cross section of the octupolar molecule is established. On the basis of the four-state model, the first hyperpolarizability of the octupolar molecule is found to be linearly proportional to the TPA cross section. This theoretical relationship is confirmed by using the ab initio calculation results. The Hammett correlation analysis of the TPA cross section and first hyperpolarizability is also presented.

15.
J Am Chem Soc ; 123(41): 10039-45, 2001 Oct 17.
Article in English | MEDLINE | ID: mdl-11592882

ABSTRACT

Two-photon absorption (TPA) properties of 1,3,5-tricyano-2,4,6-tris(styryl)benzene derivatives have been investigated. Comparison of the absorption and fluorescence spectra reveals that these compounds show large Stokes shifts, which increase gradually as the conjugation length increases. One-photon absorption and excitation spectra are similar except that the latter exhibit several peaks near lambda(max). It is also found that the one- and two-photon-induced fluorescence excitation spectra are quite similar, which indicates that the one- and two-photon allowed-excited states are the same. The peak TPA cross section values (delta(max)) measured with nanosecond pulses by the two-photon-induced fluorescence method are in the range (50-2620) x 10(-50) cm4 s/photon. The delta(max) value increases as the donor strength and conjugation length increase. A linear relationship is observed between delta(max) and beta, and this delta-beta relationship is found to serve as a useful synthetic strategy for the design of novel TPA dyes with the octupolar structure.

17.
J Air Waste Manag Assoc ; 51(5): 766-84, 2001 May.
Article in English | MEDLINE | ID: mdl-11355465

ABSTRACT

For a recent exploratory study of particulate matter (PM) compositions, origins, and impacts in the El Paso/Juarez (Paso del Norte) airshed, the authors relied on solvent extraction (SX)-gas chromatography/mass spectrometry (GC/MS) procedures to characterize 24-hr quartz fiber (QF) filter samples obtained from nine spatially distributed high-volume (Hi-Vol) PM10 samplers as well as on thermal desorption (TD)-GC/MS methods to characterize 45 time-resolved (2-hr) filter samples obtained with modified 1-m3/hr PM10 samplers. Principal component analysis and related chemometric techniques were used for data reduction and data fusion as well as for multiway data correlation. A high degree of correspondence (R2 = 0.821) was found between the rapid TD-GC/MS method (which can be carried out on 2-hr filter slices containing only microgram amounts of sample) and conventional SX-GC/MS procedures. The four main source patterns of organic PM components observed in GC/MS profiles of both temporally and spatially resolved receptor samples obtained in the El Paso/Juarez border airshed during the study period are interpreted to represent (1) vehicular emissions plus resuspended urban dust; (2) biomass combustion; (3) native vegetation detritus and resuspended agricultural dust; and (4) waste burning. Moreover, principal component analysis of combined, variance-weighted, temporally resolved TD-GC/MS data and spatially resolved SX-GC/MS data was used to determine approximate source locations for specific PM components identified in time-resolved receptor sample profiles. The same approach can be used to determine approximate circadian concentration profiles of specific PM components identified in spatially resolved receptor sample profiles.


Subject(s)
Air Pollution/analysis , Environmental Monitoring , Gas Chromatography-Mass Spectrometry , Agriculture , Circadian Rhythm , Cities , Dust , Organic Chemicals , Particle Size , Plants , Vehicle Emissions
18.
J Biosci Bioeng ; 91(1): 40-3, 2001.
Article in English | MEDLINE | ID: mdl-16232943

ABSTRACT

The nucleoid structure and the partition in the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1 were observed by a combination of phase-contrast microscopy and fluorescence microscopy. The nucleoids occurred as rounded fluorescent foci centrally located in the cells and as differences in fluorescence intensity between exponential and stationary phases. The cellular space occupied by the nucleoid in the stationary phase was larger than that in the exponential phase. Various shapes of nucleoid in the exponential-phase cells were observed, indicating that nucleoid separation was processed under cell cycle control. The number of cells which showed distinctive division stages was counted and the proportions of dividing cells were determined. About half of the observed cells were in the replication stage. More than 40% of the counted cells possessed a fully replicated but not separated form of nucleoid. Only 8% of the total cells clearly showed visible constriction. These results suggested that the post-replication period before cell division was relatively as long as the eucaryal gap period (G2); however, the period of visible cell constriction was almost the same as that of the bacteria.

19.
Mol Gen Genet ; 262(3): 559-67, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10589845

ABSTRACT

A gene encoding a cell division control protein from the hyperthermophilic archaeon Pyrococcus kodakaraensis KOD1, Pk-cdcA, was cloned and sequenced. The Pk-cdcA gene is composed of 2508 nucleotides, encoding a protein of 835 amino acids with a molecular mass of 93,666 Da. Pk-CdcA has a typical Walker-type ATPase motif and was classified as a new member of the CDC48/VCP subfamily of so-called AAA proteins. In addition, Pk-CdcA possesses a unique region composed of charged amino acids, which is not observed in other homologs from Archaea. Transcription of the gene was analyzed by primer extension and Northern analyses, revealing that Pk-cdcA is transcribed from a site 77 bases upstream of the initiation codon. Pk-CdcA and its deletion mutant Pk-CdcAdelta63, which lacks the unique inserted region, were expressed in Escherichia coli cells as His-tagged fusion proteins and purified. Both Pk-CdcA and Pk-CdcAdelta63 possess an ATPase activity, as do other CDC48/VCP proteins. However, Pk-CdcAdelta63 showed a higher level of ATPase activity and greater thermostability than Pk-CdcA. Furthermore, Pk-CdcAdelta63 has a higher Vmax value than wild type, even though the Km was unchanged. These observations indicated that the inserted region affects enzyme stability and activity. In order to investigate intracellular expression levels of Pk-CdcA, Western analysis was performed using anti-Pk-CdcA antisera obtained from immunized BALB/C mice. Equal levels of Pk-CdcA expression were observed during exponential and stationary phases. Growth phase-specific fragmentation of Pk-CdcA was found in stationary-phase cells.


Subject(s)
Adenosine Triphosphatases/genetics , Archaeal Proteins/genetics , Cell Cycle Proteins/genetics , Genes, Archaeal , Pyrococcus/genetics , Amino Acid Sequence , Base Sequence , Cloning, Molecular , DNA, Archaeal , Gene Expression , Molecular Sequence Data , Recombinant Fusion Proteins , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Transcription, Genetic , Valosin Containing Protein
20.
Pathol Int ; 48(9): 739-43, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9778113

ABSTRACT

Chondromyxoid fibroma (CMF) rarely arises in the distal phalanx of the foot and less than 20 cases have been reported in the literature. It has also been known to show a wide spectrum of histology mimicking other primary bone tumors. An unusual case of CMF arising in the distal phalanx of the left great toe is reported because of its unique anatomic site of origin and histology. A 53-year-old female presented with a slow growing, painful great toe of the left foot which she had had for 3 years. She had first noticed the mass 25 years ago. On admission, plain X-ray revealed an osteolytic mass with a sclerotic margin expanding to the distal phalanx of the great toe. Interestingly, the lesion was microscopically composed of hypercellular chondromyxoid lobules separated by hypocellular fibrous tissue, which is in contrast to the typical histology of CMF. In addition, the lesion showed an aggregate of tumor cells with pleomorphic multinucleate or giant nuclei within the chondromyxoid matrix, which were not similar to the osteoclast-like type. Perhaps these unusual histological findings may be associated with its long duration and presenting location.


Subject(s)
Bone Neoplasms/pathology , Chondroblastoma/pathology , Hallux , Biomarkers, Tumor/metabolism , Bone Neoplasms/metabolism , Chondroblastoma/metabolism , Female , Humans , Immunohistochemistry , Magnetic Resonance Imaging , Middle Aged
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