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1.
Phys Rev Lett ; 118(3): 033202, 2017 Jan 20.
Article in English | MEDLINE | ID: mdl-28157370

ABSTRACT

The hitherto unexplored two-photon doubly excited states [Ne^{*}(2p^{-1}3s)]_{2} were experimentally identified using the seeded, fully coherent, intense extreme ultraviolet free-electron laser FERMI. These states undergo ultrafast interatomic Coulombic decay (ICD), which predominantly produces singly ionized dimers. In order to obtain the rate of ICD, the resulting yield of Ne_{2}^{+} ions was recorded as a function of delay between the extreme ultraviolet pump and UV probe laser pulses. The extracted lifetimes of the long-lived doubly excited states, 390(-130/+450) fs, and of the short-lived ones, less than 150 fs, are in good agreement with ab initio quantum mechanical calculations.

2.
Nat Commun ; 8: 14277, 2017 01 30.
Article in English | MEDLINE | ID: mdl-28134238

ABSTRACT

Inner-shell ionization of an isolated atom typically leads to Auger decay. In an environment, for example, a liquid or a van der Waals bonded system, this process will be modified, and becomes part of a complex cascade of relaxation steps. Understanding these steps is important, as they determine the production of slow electrons and singly charged radicals, the most abundant products in radiation chemistry. In this communication, we present experimental evidence for a so-far unobserved, but potentially very important step in such relaxation cascades: Multiply charged ionic states after Auger decay may partially be neutralized by electron transfer, simultaneously evoking the creation of a low-energy free electron (electron transfer-mediated decay). This process is effective even after Auger decay into the dicationic ground state. In our experiment, we observe the decay of Ne2+ produced after Ne 1s photoionization in Ne-Kr mixed clusters.

3.
Faraday Discuss ; 194: 621-638, 2016 12 16.
Article in English | MEDLINE | ID: mdl-27711803

ABSTRACT

The ultra-bright femtosecond X-ray pulses provided by X-ray Free Electron Lasers (XFELs) open capabilities for studying the structure and dynamics of a wide variety of biological and inorganic systems beyond what is possible at synchrotron sources. Although the structure and chemistry at the catalytic sites have been studied intensively in both biological and inorganic systems, a full understanding of the atomic-scale chemistry requires new approaches beyond the steady state X-ray crystallography and X-ray spectroscopy at cryogenic temperatures. Following the dynamic changes in the geometric and electronic structure at ambient conditions, while overcoming X-ray damage to the redox active catalytic center, is key for deriving reaction mechanisms. Such studies become possible by using the intense and ultra-short femtosecond X-ray pulses from an XFEL, where sample is probed before it is damaged. We have developed methodology for simultaneously collecting X-ray diffraction data and X-ray emission spectra, using an energy dispersive spectrometer, at ambient conditions, and used this approach to study the room temperature structure and intermediate states of the photosynthetic water oxidizing metallo-protein, photosystem II. Moreover, we have also used this setup to simultaneously collect the X-ray emission spectra from multiple metals to follow the ultrafast dynamics of light-induced charge transfer between multiple metal sites. A Mn-Ti containing system was studied at an XFEL to demonstrate the efficacy and potential of this method.


Subject(s)
Crystallography, X-Ray , Electrons , Lasers , Catalysis , X-Rays
4.
Phys Rev Lett ; 117(27): 276806, 2016 Dec 30.
Article in English | MEDLINE | ID: mdl-28084773

ABSTRACT

Ne clusters (∼5000 atoms) were resonantly excited (2p→3s) by intense free electron laser (FEL) radiation at FERMI. Such multiply excited clusters can decay nonradiatively via energy exchange between at least two neighboring excited atoms. Benefiting from the precise tunability and narrow bandwidth of seeded FEL radiation, specific sites of the Ne clusters were probed. We found that the relaxation of cluster surface atoms proceeds via a sequence of interatomic or intermolecular Coulombic decay (ICD) processes while ICD of bulk atoms is additionally affected by the surrounding excited medium via inelastic electron scattering. For both cases, cluster excitations relax to atomic states prior to ICD, showing that this kind of ICD is rather slow (picosecond range). Controlling the average number of excitations per cluster via the FEL intensity allows a coarse tuning of the ICD rate.

5.
J Exp Biol ; 212(Pt 24): 4072-8, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19946086

ABSTRACT

Ultrasonic hearing is widespread among moths, but very few moth species have been reported to produce ultrasounds for sexual communication. In those that do, the signals are intense and thus well matched for long distance communication. By contrast, males of the Asian corn borer moth (Crambidae) were recently shown to whisper extremely low-intensity ultrasonic courtship songs close to females. Since low sound levels will prevent eavesdropping by predators, parasites and conspecific rivals, we predicted low intensity ultrasound communication to be widespread among moths. Here we tested 13 species of moths including members of the Noctuidae, Arctiidae, Geometridae and Crambidae. Males of nine species, 70%, produced broadband ultrasound close to females. Peak frequencies ranged from 38 to above 100 kHz. All sounds were of low intensity, 43-76 dB SPL at 1 cm [64+/-10 dB peSPL (mean +/- s.d.), N=9 species]. These quiet and/or hyper-frequency ultrasounds are audible to nearby mates, but inaudible to unintended receivers. Although largely unknown because it is so inconspicuous, acoustic communication using low intensity ultrasound appears to be widespread among hearing moths. Thus, acoustic communication may be the norm rather than the exception.


Subject(s)
Courtship , Moths/physiology , Ultrasonics , Vocalization, Animal/physiology , Animals , Chiroptera/physiology , Female , Male , Pressure , Sound
6.
Ophthalmology ; 108(6): 1129-33, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11382641

ABSTRACT

OBJECTIVE: To clarify the characteristics of ocular manifestations in Churg-Strauss syndrome (allergic granulomatosis and angiitis). DESIGN: Two interventional case reports and literature review. PARTICIPANTS: Two patients with Churg-Strauss syndrome with ocular manifestations are described; 15 previously reported cases and the present 2 cases of Churg-Strauss syndrome with ocular manifestations are reviewed. INTERVENTION: Ocular manifestations were divided into two groups: orbital inflammatory pseudotumor and ischemic vasculitis. MAIN OUTCOME MEASURES: The onset, conjunctival involvement, orbital imaging, antineutrophil cytoplasmic antibodies (ANCA), and visual prognosis were evaluated. RESULTS: The characteristics of the orbital inflammatory pseudotumor type (eight cases) are chronic onset, positive conjunctival involvement, abnormalities in orbital imaging studies, negative ANCA, and good visual prognosis. The ischemic type (nine cases) is characterized by sudden onset, no conjunctival involvement or abnormalities in imaging studies, positive ANCA, and occasional poor visual prognosis. CONCLUSIONS: Orbital inflammatory pseudotumor and ischemic vasculitis may represent two essential characteristics of Churg-Strauss syndrome, granulomatosis and angiitis, respectively. The clinical features of the two types are so distinct that differentiation may be meaningful for diagnosis and treatment of Churg-Strauss syndrome with ocular manifestations.


Subject(s)
Churg-Strauss Syndrome/diagnosis , Conjunctival Diseases/diagnosis , Dacryocystitis/diagnosis , Eye/blood supply , Ischemia/diagnosis , Orbital Pseudotumor/diagnosis , Adult , Antibodies, Antineutrophil Cytoplasmic/analysis , Eosinophilia/diagnosis , Humans , Magnetic Resonance Imaging , Male , Middle Aged
7.
Vet Immunol Immunopathol ; 77(1-2): 15-25, 2000 Nov 23.
Article in English | MEDLINE | ID: mdl-11068063

ABSTRACT

Recombinant baculoviruses that express recombinant bovine interleukin-12 (rboIL-12) subunits, p35 and p40 subunits were constructed. A recombinant virus containing the p40 subunit gene expressed the p40 subunit as a 40kDa monomer and an 80kDa disulfide-linked homodimer in the infected insect cells and in the culture supernatant. The p35 subunit was expressed in a 30kDa monomer in the infected cells but not in the supernatant. Superinfection of both recombinant viruses into the cells in a spinner flask resulted in the formation of a 70kDa disulfide-bonded heterodimer detected in the supernatant by immunoblotting using anti-p40 and anti-p35 subunits antibodies. The superinfected culture supernatant showed induction of IFNgamma mRNA synthesis and IFNgamma production in bovine peripheral blood mononuclear cells. Thus, the bioactive rboIL-12 was produced in large scale using a baculovirus expression system.


Subject(s)
Interleukin-12/genetics , Nucleopolyhedroviruses/genetics , Animals , Base Sequence , Biological Assay , Cattle , Cell Line , Cloning, Molecular , DNA Primers/genetics , DNA, Complementary/genetics , Dimerization , Gene Expression , Genetic Vectors , Interferon-gamma/biosynthesis , Interferon-gamma/genetics , Interleukin-12/biosynthesis , Interleukin-12/chemistry , Leukocytes, Mononuclear/immunology , Protein Subunits , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Spodoptera
8.
Transplantation ; 70(3): 441-6, 2000 Aug 15.
Article in English | MEDLINE | ID: mdl-10949185

ABSTRACT

BACKGROUND: Oval cells are liver cells capable of differentiating into either hepatocytes or biliary epithelial cells. We compared growth of hepatocytes and biliary epithelial cells between spleens transplanted with oval cell-free and oval cell-enriched rat liver cells. METHODS: Oval cell-enriched liver cells were obtained from livers of adult rats that had undergone treatment with acetylaminofluorene and partial hepatectomy, although oval cell-free liver cells were obtained from livers of untreated rats. Hepatocyte and biliary epithelial cell growth in the spleen was evaluated by counting periodic acid-Schiff-positive cells and cytokeratin 19-positive cells respectively in sections from transplanted spleens. RESULTS: Spleens transplanted with oval cell-free liver cells and spleens transplanted with oval cell-enriched liver cells contained similar numbers of hepatocytes after 2 weeks. Numbers of hepatocytes in spleens transplanted with oval cell-free liver cells decreased markedly at 4 and 8 weeks, then increasing slightly until 32 weeks. In spleens transplanted with oval cell-enriched liver cells, numbers of hepatocytes decreased only slightly at 4 weeks and then increased markedly. At 4, 8, 12, 16, 24, and 32 weeks, numbers of hepatocytes in spleens transplanted with oval cell-enriched liver cells respectively were 2.3, 3.5, 4.5, 6.7, 6.3, and 15.1 times hepatocyte numbers in spleens transplanted with oval cell-free liver cells. Numbers of biliary epithelial cells in spleens receiving oval cell-enriched liver cells showed changes similar to those in spleens transplanted with oval cell-free liver cells, increasing markedly at 4 weeks and then markedly and rapidly decreasing. CONCLUSIONS: Intrasplenic transplantation of oval cell-enriched liver cells enhanced growth of hepatocytes compared with transplantation of oval cell-free liver cells; this was not true for biliary epithelial cells.


Subject(s)
Cell Transplantation/pathology , Liver Transplantation/pathology , Liver/cytology , Animals , Biliary Tract/cytology , Cell Count , Cell Differentiation , Epithelial Cells/cytology , Immunohistochemistry , Keratins/metabolism , Liver/metabolism , Male , Rats , Rats, Inbred F344 , Spleen/cytology , Spleen/surgery , Time Factors , Transplantation, Heterotopic
9.
J Pediatr Surg ; 35(8): 1198-204, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10945693

ABSTRACT

BACKGROUND/PURPOSE: The effect of TNP-470, an angiogenesis inhibitor, on the growth of a hepatoblastoma transplanted into nude mice was examined. METHODS: A hepatoblastoma obtained from a 3-year-old girl was serially transplanted into nude mice subcutaneously, and the transplant tumors of the seventh and eighth generations were used for experiments. Expression of various markers in the tumors was examined immunohistochemically. TNP-470 was injected subcutaneously every other day into tumor-bearing mice from 3 weeks after tumor transplantation. The proliferation of tumor cells and endothelial cells was estimated by means of the bromodeoxyuridine labeling index. RESULTS: The original hepatoblastoma showed the histology of the epithelial type, consisting of both the fetal and embryonal subtypes and was positively stained with anti-alpha-fetoprotein (AFP), anti-cytokeratin-19 and polyclonal anticarcinoembryonic antigen antibodies, and an antihuman hepatocyte antibody (hepatocyte paraffin 1). The transplant tumors consisted of solid nests of tumor cells with numerous vascular lakes of various sizes, and showed positive staining with all antibodies that reacted positively with the original hepatoblastoma. Injections of TNP-470 at the doses of 15 mg and 30 mg/kg body weight suppressed the tumor growth and the increase in the serum level of AFP dose dependently. Injections of TNP-470 also suppressed the proliferation of tumor cells and endothelial cells in the tumors. CONCLUSIONS: Hepatoblastomas maintained in nude mice retained the immunohistochemical characteristics of the original hepatoblastoma, and TNP-470 suppressed the growth of hepatoblastomas transplanted into nude mice. TNP-470 may be worth investigating further as to its usefulness as a therapy for hepatoblastomas.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Hepatoblastoma/drug therapy , Liver Neoplasms/drug therapy , Sesquiterpenes/pharmacology , Animals , Child, Preschool , Cyclohexanes , Female , Hepatoblastoma/metabolism , Humans , Immunohistochemistry , Liver Neoplasms/metabolism , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Transplantation , O-(Chloroacetylcarbamoyl)fumagillol , Transplantation, Heterologous , alpha-Fetoproteins/metabolism
10.
Invest Ophthalmol Vis Sci ; 39(2): 358-63, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9477994

ABSTRACT

PURPOSE: To develop a highly sensitive method for in vivo quantitation of intravitreal peroxides by vitreous fluorophotometry with 2',7'-dichlorofluorescin (DCFH), a hydrogen peroxide (H2O2)-sensitive fluorescent dye, and to measure peroxides in the vitreous humor after panretinal laser photocoagulation (PRP). METHODS: In the presence of H2O2 and lipid hydroperoxides, nonfluorescent DCFH was oxidized to highly fluorescent 2',7'-dichlorofluorescein (DCF; excitation, 495 nm; emission, 520 nm), which is detectable by vitreous fluorophotometry. Reactions of DCFH, including hematin with various concentrations of H2O2, were investigated in vivo. Fluorophotometry with DCFH was performed 1, 7, 14, and 28 days and 2 months after argon laser PRP. Untreated eyes served as the controls. RESULTS: Exogenously applied H2O2 oxidized DCFH to DCF in a dose-dependent manner, ranging from 6 x 10(-8) mol/l to 6 x 10(-5) mol/l in concentration in vivo. Intravitreal DCF concentration was 83.7 +/- 6.8 nmol/l in control eyes. A significant increase of DCF was detected 1 day after PRP (330.7 +/- 123.8 nmol/l, P < 0.002). The increase peaked on day 7 (352.4 +/- 239.5 nmol/l, P < 0.002) and remained elevated at 2 months after PRP (161.8 +/- 51.4 nmol/l, P < 0.01). CONCLUSIONS: This method allowed a highly sensitive quantitation of intravitreal peroxides in vivo. The authors' findings indicated that PRP induces increased production of peroxides in rabbit vitreous for 2 months. The data suggested that persistently high levels of peroxides in the vitreous humor affect the development of vitreous liquefaction after PRP.


Subject(s)
Fluorophotometry , Laser Coagulation , Peroxides/metabolism , Retina/surgery , Vitreous Body/metabolism , Animals , Dose-Response Relationship, Drug , Fluoresceins/metabolism , Fluorescent Dyes/metabolism , Fluorophotometry/methods , Hydrogen Peroxide/metabolism , Hydrogen Peroxide/pharmacology , Lipid Peroxides/metabolism , Oxidation-Reduction , Rabbits , Vitreous Body/drug effects
11.
Jpn J Ophthalmol ; 41(5): 319-23, 1997.
Article in English | MEDLINE | ID: mdl-9363561

ABSTRACT

Although cataract extraction with intraocular lens implantation (IOL) is being used for increasing numbers of patients, there is still insufficient information regarding the long-term outcome for these patients. In this retrospective study of 140 eyes of 102 patients, 97 eyes (69%) achieved a best visual acuity of 20/40 or better. After a minimum 6-month postoperative period, 26 eyes (19%) had developed retinopathy: eight eyes progressed from nonproliferative to proliferative retinopathy. Glycosylated hemoglobin levels and fasting blood glucose were significantly higher at time of surgery in the eight that progressed than in those who did not (P = 0.002, P = 0.034). There were 65 unilateral IOL implantations; in 10 (15%) of these eyes, retinopathy progressed. Retinopathy also progressed in 70% of the fellow eyes of these patients. In patients whose retinopathy did not progress, 95% of the fellow eyes also showed no progression. Also, patients with progression in the pseudophakic eye frequently had progression in the fellow unoperated eye. Postoperative progression was symmetrical (P = 0.0001). Our analysis suggests that progression of diabetic retinopathy following IOL implantation can be correlated to diabetic control at the time of surgery.


Subject(s)
Cataract Extraction , Diabetes Mellitus, Type 2/complications , Diabetic Retinopathy/complications , Lens Implantation, Intraocular , Adult , Aged , Aged, 80 and over , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/physiopathology , Diabetic Retinopathy/metabolism , Diabetic Retinopathy/physiopathology , Disease Progression , Female , Glycated Hemoglobin/metabolism , Humans , Intraoperative Complications , Longitudinal Studies , Male , Middle Aged , Polymethyl Methacrylate , Postoperative Complications , Prognosis , Retrospective Studies , Visual Acuity/physiology
12.
Curr Eye Res ; 16(7): 633-9, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9222079

ABSTRACT

PURPOSE: A scleral plug made of biodegradable polymer implanted at the pars plana was evaluated to determine its ability to control the intravitreal release of ganciclovir. METHODS: Scleral plugs containing 25% ganciclovir were prepared with poly(lactic-glycolic acid) (molecular weight, 121 kDa). The release of ganciclovir was evaluated in vitro by spectrophotometry. In vivo intravitreal ganciclovir concentrations were measured by high performance liquid chromatography following plug implantation in pigmented rabbits. The biocompatibility of the device was determined by indirect ophthalmoscopy, electroretinography, and light and electron microscopy. RESULTS: The in vitro study showed that the plug released ganciclovir throughout a 10-week period. The in vivo study demonstrated that the plugs maintained the drug concentration in the vitreous in a therapeutic range adequate to treat cytomegalovirus (CMV) retinitis for 12 weeks. No significant retinal toxicity was observed. CONCLUSIONS: This study demonstrated that this drug delivery system can potentially be useful to treat CMV retinitis.


Subject(s)
Biocompatible Materials , Ganciclovir/administration & dosage , Lactic Acid , Polyglycolic Acid , Polymers , Prostheses and Implants , Vitreous Body , Animals , Biodegradation, Environmental , Ganciclovir/pharmacokinetics , Polylactic Acid-Polyglycolic Acid Copolymer , Rabbits , Vitreous Body/metabolism
13.
Jpn J Antibiot ; 50(3): 219-50, 1997 Mar.
Article in Japanese | MEDLINE | ID: mdl-9575353

ABSTRACT

The frequencies of isolation and susceptibilities to antimicrobial agents were investigated on 704 bacterial strains isolated from patients with urinary tract infections (UTIs) in 11 hospitals during the period of June 1995 to May 1996. Of the above bacterial isolates, Gram-positive bacteria accounted for 29.8% and a majority of them were Enterococcus faecalis. Gram-negative bacteria accounted for 70.2% and most of them were Escherichia coli. Susceptibilities of several isolated bacteria to antimicrobial agents were as followed; 1. Enterococcus faecalis Ampicillin (ABPC) and imipenem (IPM) showed the highest activities against E. faecalis isolated from patients with UTIs. The MIC90S of them were 1 microgram/ml. Vancomycin (VCM) and piperacillin (PIPC) were also active with the MIC90S of 2 micrograms/ml and 4 micrograms/ml, respectively. The others had low activities with the MIC90S of 16 micrograms/ml or above. 2. Staphylococcus aureus including MRSA VCM showed the highest activities against S. aureus isolated from patients with UTIs. Its MIC90 was 1 microgram/ml against both S. aureus and MRSA. Arbekacin (ABK) was also active with the MIC90 of 2 micrograms/ml. The other except minocycline (MINO) had very low activities with the MIC90S of 64 micrograms/ml or above. 3. Staphylococcus epidermidis ABK and MINO showed the strongest activities against S. epidermidis isolated from patients with UTIs. The MIC90S of them were 0.25 microgram/ml. VCM was also active with the MIC90 of 1 microgram/ml. The MIC90S of cephems ranged from 2 micrograms/ml to 16 micrograms/ml in 1994, but they ranged from 8 micrograms/ml to 128 micrograms/ml in 1995. These results indicated that some resistances existed among S. epidermidis to cephems. 4. Streptococcus agalactiae All drugs except gentamicin (GM) were active against S. agalactiae. ABPC, cefmenoxime (CMX), IPM, erythromycin (EM), clindamycin (CLDM) and clarithromycin (CAM) showed the highest activities. The MICs for all strains were lower than 0.125 microgram/ml. The MIC90S of the others were 2 micrograms/ml or below. 5. Citrobacter freundii IPM showed the highest activity against C. freundii isolated from patients UTIs. Its MIC90 was 1 microgram/ml. GM was also active with the MIC90 of 2 micrograms/ml. Cefpirome (CPR), cefozopran (CZOP) and amikacin (AMK) were also active with the MIC90S of 4 micrograms/ml. Penicillins and cephems except CMX, CPR and CZOP showed low activities with MIC90S of 256 micrograms/ml or above. 6. Enterobacter cloacae IPM showed the highest activity against E. cloacae. The MICs for all strains were equal to or lower than 1 microgram/ml. MINO and tosufloxacin (TFLX) were also active with the MIC90S of 8 micrograms/ml. Penicillins and cephems except CPR and CZOP showed lower activities with the MIC90S of 256 micrograms/ml or above. 7. Escherichia coli. Most of the antimicrobial agents were active against E. coli. Particularly CPR, CZOP and IPM showed the highest activities against E. coli. The MICs for all strains were equal to or lower than 0.5 microgram/ml. CMX and TFLX were also active with the MIC90S of 0.125 microgram/ml or below. Penicillins were slightly active with MIC90S of 128 micrograms/ml or above. 8. Klebsiella pneumoniae K. pneumoniae was susceptible to all drugs except penicillins, with MIC90S of 2 micrograms/ml or below. Carumonam (CRMN) had the strongest activity against K. pneumoniae, the MICs for all strains were equal to or lower than 0.125 microgram/ml. Comparing with the result of 1994, the sensitivities of K. pneumoniae against all drugs had obviously changed into a better state. For example, the MIC90S of cephems ranged from 0.25 microgram/ml to 16 micrograms/ml in 1994, but they were all lower than 2 micrograms/ml in 1995. 9. Proteus mirabilis P. mirabilis was susceptible to a majority of drugs. CMX, ceftazidime (CAZ), cefixime (CFIX), and CRMN showed the highest activities against P. mirabilis isolated from patients with UTIs. MICs of CRMN for all


Subject(s)
Anti-Bacterial Agents/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Urinary Tract Infections/microbiology , Drug Resistance, Microbial , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/isolation & purification , Humans , Time Factors
14.
J Neurol Sci ; 145(1): 41-7, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9073027

ABSTRACT

To characterize the non-caseating granuloma formation in granulomatous myositis, we analyzed infiltrating mononuclear cells in 7 patients including 2 sarcoid patients, using monoclonal antibodies with a modified immunoperoxidase method. All granulomas consisting of epithelioid, infiltrating mononuclear cells and multinucleated giant cells had markedly increased numbers of CD45Ro-positive cells. The infiltrating inflammatory cells were mostly T lymphocytes and macrophages. The majority of T lymphocytes behaved as T helper/inducer subtype, expressing CD4 positivity. Although the ratio of CD4- to CD8-positive cells in the granuloma in muscle biopsies was not significantly different from that in other organs seen in systemic sarcoidosis, T helper/inducer and T suppressor/cytotoxic cells showed some characteristic distributions: CD4-positive cells accumulated in the center of, and CD8-positive cells at the periphery of, the granuloma. The distribution of infiltrating cells did not differ between muscle biopsies from patients with and without systemic sarcoidosis, suggesting that both groups share the same pathogenetic mechanism in granuloma formation.


Subject(s)
CD4-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/pathology , Myositis/pathology , Aged , Antigens, CD20/analysis , Biopsy , CD4-Positive T-Lymphocytes/chemistry , CD56 Antigen/analysis , CD8-Positive T-Lymphocytes/chemistry , Evaluation Studies as Topic , Female , Humans , Immunohistochemistry , Immunophenotyping , Leukocyte Common Antigens/analysis , Male , Middle Aged , Muscle, Skeletal/immunology , Muscle, Skeletal/pathology , Sarcoidosis/immunology , Sarcoidosis/pathology
15.
Invest Ophthalmol Vis Sci ; 38(13): 2721-8, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9418724

ABSTRACT

PURPOSE: To establish a new fluorophotometric method to quantitate oxidative stress in the retina in vivo with a hydrogen peroxide (H2O2)-sensitive fluorescent dye. METHODS: For in vitro fluorophotometric study, nonfluorescent 2',7'-dichlorofluorescein (DCFH) was incubated with H2O2 (10 pM to 100 nM), and the production of fluorescent 2',7'-dichlorofluorescein (DCF) was measured with fluorophotometric analysis. The inhibitory effect of catalase was also examined. For in vivo fluorophotometric study, rabbit eyes received vitrectomy and were perfused with 5 microM 2',7'-dichlorofluorescein diacetate (DCF-DA) or 2',7'-dichlorofluorescein diacetate (DCFH-DA). For oxidative stress, 300 microM H2O2 was infused after perfusion of DCFH-DA. Fluorophotometric measurements of the chorioretinal peak were performed. The eyes were enucleated for fluorescent microscopic examination to determine the localization of DCF fluorescence. RESULTS: H2O2 converted DCFH to DCF in a dose-dependent manner, which was inhibited by catalase dose dependently. In vivo fluorophotometric study showed DCF-DA and DCFH-DA caused production of 2006 +/- 274 picomole/ml (mean +/- SD, n = 5) and 8.35 +/- 1.11 picomole/ml (n = 5), respectively, in the chorioretinal peak. DCFH-DA with stimulation by H2O2 induced 30.7 +/- 13.1 (n = 4) picomole/ml DCF. Fluorescent microscopy showed DCF production in the retina was significant in the eye treated with DCF-DA and minimal in the eye treated with DCFH-DA. Moderate DCF production in the nerve fiber layer was observed in the eye treated with DCFH-DA and H2O2. CONCLUSIONS: This new fluorophotometric method with DCFH-DA may be useful in quantitatively evaluating oxidative stress in the retina in vivo.


Subject(s)
Oxidative Stress/physiology , Retina/metabolism , Animals , Fluoresceins/metabolism , Fluorescent Dyes , Fluorophotometry , Hydrogen Peroxide/metabolism , Hydrogen Peroxide/pharmacology , Microscopy, Fluorescence , Oxidative Stress/drug effects , Rabbits , Retina/drug effects
17.
Invest Ophthalmol Vis Sci ; 37(7): 1444-50, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8641847

ABSTRACT

PURPOSE: To detect intravitreal peroxides in vivo by a new fluorophotometric method with a hydrogen peroxide (H2O2)-sensitive fluorescent dye. METHODS: The authors used a 2',7'-dichlorofluorescin (DCFH) assay to measure oxidative status in the rabbit vitreous. In the presence of H2O2 and lipid hydroperoxides, nonfluorescent DCFH in the vitreous is oxidized to highly fluorescent 2',7'-dichlorofluorescein (DCF; excitation, 495 nm; emission, 520 nm) that is detectable by fluorophotometry. Reactions of DCFH with various concentrations of H2O2 were investigated in vitro and in vivo. An inhibitory effect of catalase also was monitored. Vitreous fluorophotometry with DCFH was performed immediately and at 3, 7, and 28 days after constant light exposure to the retina (1800 lux, 24 hours) as an oxidative stress. RESULTS: In vitro study revealed that H2O2 oxidized DCFH to DCF in a dose-dependent manner, ranging from 0.1 to 100 mmol/1 in concentration. Catalase inhibited DCF production. Vitreous fluorophotometry demonstrated that H2O2 oxidized DCFH to DCF in vivo in a dose-dependent manner, ranging from 0.06 to 60 mmol/1 in concentration. DCF production in the vitreous significantly increased immediately (P = 0.03) and at 3 days (P = 0.01) and 7 days (P = 0.01) after light exposure, and it returned to the pretreatment level by day 28. CONCLUSIONS: The results suggest that this fluorophotometric method quantitatively can detect intravitreal peroxides in vivo. This method will be helpful to study the oxidative status in some experimental pathologic conditions.


Subject(s)
Fluorophotometry/methods , Hydrogen Peroxide/analysis , Lipid Peroxides/analysis , Vitreous Body/chemistry , Animals , Dose-Response Relationship, Drug , Fluoresceins , Fluorescent Dyes , Oxidation-Reduction , Rabbits
18.
Curr Eye Res ; 14(6): 473-7, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7671629

ABSTRACT

We investigated the use of a scleral plug of biodegradable polymer implanted at the pars plana to create a controlled drug-delivery system in the vitreous. We evaluated the efficacy of a plug containing doxorubicin hydrochloride to treat experimental proliferative vitreoretinopathy (PVR) in pigmented rabbits. An implantable device on the sclera, which imitates a scleral plug, containing 1% doxorubicin, was prepared with poly(lactic acid) (molecular weight, 20,000). The release of doxorubicin in phosphate-buffered saline was evaluated by spectro-photometry. After pars plana vitrectomy and plug implantation, concentrations of doxorubicin in the vitreous humor of the rabbits were measured by high performance liquid chromatography. The release profiles were evaluated during 5 weeks in vitro and 4 weeks in vivo. Cultured homologous fibroblasts were injected into the vitreous space to induce experimental PVR after gas compression of the vitreous. The scleral plugs were implanted at the pars plana in treatment animals (n = 11). Control rabbits (n = 11) were followed up without implantation after PVR induction. All eyes of the control group developed tractional retinal detachment at day 28, while the incidence of retinal detachment was decreased to 64% in the treated eyes. (P = 0.002). The implantation of the scleral plug effectively inhibited intravitreous proliferation of fibroblasts. This study demonstrated that the scleral plug of biodegradable polymers may have potential as a treatment modality for PVR.


Subject(s)
Doxorubicin/administration & dosage , Lactates , Lactic Acid , Polymers , Vitreoretinopathy, Proliferative/drug therapy , Animals , Biodegradation, Environmental , Cell Division/drug effects , Chromatography, High Pressure Liquid , Delayed-Action Preparations , Doxorubicin/pharmacokinetics , Drug Implants , Fibroblasts/drug effects , Polyesters , Rabbits , Retinal Detachment/prevention & control , Vitrectomy , Vitreous Body/cytology , Vitreous Body/metabolism
19.
Nippon Ganka Gakkai Zasshi ; 99(2): 200-3, 1995 Feb.
Article in Japanese | MEDLINE | ID: mdl-7701992

ABSTRACT

We retrospectively studied 255 eyes of 190 diabetic patients who underwent cataract extraction with posterior chamber intraocular lens (IOL) implantation. One hundred forty-six eyes (57.3%) achieved the best visual acuity of 20/30 or better and 221 eyes (86.7%) achieved the acuity of 20/100 or better. Among 161 eyes that were followed up over 6 months, 26 eyes (16%) showed a progression of the retinopathy. Eight eyes developed proliferative retinopathy from non-proliferative retinopathy. The level of glycosylated hemoglobin of the progression group at the time of surgery was significantly higher than that of the non-progression group (8.0 +/- 2.4% vs 6.8 +/- 1.6%, p < 0.05). Sixty-five patients received IOL implantation in one eye. Of these patients, 10 eyes (15%) showed progression of the retinopathy. Seventy percent of the fellow eyes also showed the progression, where as 95% of the non-progression group did not show progression in the fellow eyes. The results suggested that the progression of diabetic retinopathy after IOL implantation was correlated with diabetic control at the time of surgery. Additionally, patients who developed the progression of the retinopathy in pseudophakic eyes frequently showed the progression in the fellow unoperated eyes.


Subject(s)
Diabetes Complications , Lenses, Intraocular/rehabilitation , Adult , Aged , Aged, 80 and over , Cataract/complications , Cataract Extraction , Diabetic Retinopathy/complications , Humans , Middle Aged , Prognosis , Retrospective Studies , Visual Acuity
20.
No To Shinkei ; 46(9): 889-94, 1994 Sep.
Article in Japanese | MEDLINE | ID: mdl-7999449

ABSTRACT

A case of Klippel-Trenaunay-Weber syndrome associated with multiple intracranial angiomas was reported. Intracranial angiomas with Klippel-Trenaunay-Weber syndrome is very rare. Only 4 cases are known to this day. A 24-year-old man fell at his workplace and suffered a head injury. He was admitted to our hospital. Neurological examination revealed no abnormality. However, physiological examination demonstrated hyperplasia and cutaneous hemangiomas of left lower leg, malformation of the left eyelid and clouding of the left cornea. CT showed left hemispheric atrophy and subdural effusion. MRI demonstrated multiple flow voids at the left cerebellar hemisphere and at pons. Cerebral angiogram demonstrated left cerebellar AVM and pontine angioma. Feeding arteries of the AVM were left superior cerebellar artery and left posterior inferior cerebellar artery. Those of the pontine angioma could not be identified. No spinal angiomas were revealed. While spinal angiomas associated with this syndrome are known, association of intracranial lesions are rare. Reported anomalies are angiomas, hemi-hypertrophy of skull and brain, carotid occlusion, megadolicoanomaly of the basilar artery, meningioma and glioma. Our case report with cerebral angiomas is the first one in Japan. We postulate that anomaly of our case originated at the Streeter's 2nd-3rd stage or that multiple anomalies occurred. We emphasize that intracranial, spinal or visceral angiomas, which can be fatal if it bleeds, should be routinely examined in Klippel-Trenaunay-Weber syndrome.


Subject(s)
Brain Neoplasms/complications , Hemangioma/complications , Klippel-Trenaunay-Weber Syndrome/complications , Neoplasms, Multiple Primary/complications , Adult , Brain Neoplasms/congenital , Hemangioma/congenital , Humans , Male , Neoplasms, Multiple Primary/congenital
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