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1.
J Dent Res ; 87(8): 757-61, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18650548

ABSTRACT

Functional monomers in adhesive systems can improve bonding by enhancing wetting and demineralization, and by chemical bonding to calcium. This study tested the hypothesis that small changes in the chemical structure of functional monomers may improve their bonding effectiveness. Three experimental phosphonate monomers (HAEPA, EAEPA, and MAEPA), with slightly different chemical structures, and 10-MDP (control) were evaluated. Adhesive performance was determined in terms of microtensile bond strength of 4 cements that differed only for the functional monomer. Based on the Adhesion-Decalcification concept, the chemical bonding potential was assessed by atomic absorption spectrophotometry of the dissolution rate of the calcium salt of the functional monomers. High bond strength of the adhesive cement corresponded to low dissolution rate of the calcium salt of the respective functional monomer. The latter is according to the Adhesion-Decalcification concept, suggestive of a high chemical bonding capacity. We conclude that the adhesive performance of an adhesive material depends on the chemical structure of the functional monomer.


Subject(s)
Acrylates/chemistry , Adhesives/chemistry , Methacrylates/chemistry , Organophosphonates/chemistry , Resin Cements/chemistry , Dental Bonding , Dentin-Bonding Agents/chemistry , Surface Properties
3.
Biochim Biophys Acta ; 1474(2): 251-61, 2000 Apr 06.
Article in English | MEDLINE | ID: mdl-10742606

ABSTRACT

Förster resonance energy transfer (FRET) was used to study the conformational dynamics of bradykinin related peptides. The fluorescent probe aminobenzoic acid (Abz) bound to the amino terminal of bradykinin maintained its fluorescence characteristics, like high quantum yield and excited state decay dominated by a lifetime of 8.3 ns. The binding of the acceptor group N-[2, 4-dinitrophenyl]-ethylenediamine (EDDnp) to the carboxy terminal of Abz labeled bradykinin resulted in a drastic decrease of the fluorescence intensity and in a fastening of the excited state decay. The change of the decay kinetics to an heterogeneous process, precludes the use of energy transfer models based on a single fixed distance between donor and acceptor. The computational package CONTIN was employed to the analysis of time-resolved fluorescence data, allowing the recovery of a distance distribution between donor and acceptor corresponding to the end-to-end distance of the labeled peptide. The distance distribution reflects the occurrence of distinct conformations for the peptide, that coexist in equilibrium during the fluorescence lifetime. We observed three distance populations for bradykinin in water, that merged to two populations when the solvent was trifluoroethanol (TFE). The results were consistent with those obtained from circular dichroism spectroscopy, that showed structural flexibility in water and the presence of more defined secondary structure in TFE. We also studied several peptides related to bradykinin, and the results emphasized the formation of turns involving the proline residues and the decrease of conformational flexibility induced by using TFE as the solvent.


Subject(s)
Bradykinin/chemistry , Amino Acid Sequence , Circular Dichroism , Energy Transfer , Fluorescence Polarization , Fluorescent Dyes
4.
Dig Liver Dis ; 37(7): 515-21, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15975539

ABSTRACT

BACKGROUND AND AIM: Selective granulocyte and monocyte/macrophage adsorptive apheresis is to increase the turnover of infected leucocytes and has increased CD4+ T cells, which are necessary for actions of interferon-alpha on hepatitis C virus. Therefore, granulocyte and monocyte apheresis was to enhance the efficacy of interferon + ribavirin. METHODS: Fifteen patients, 12 had interferon resistant hepatitis C virus and 3 were interferon naive. Hepatitis C virus genotype was 1b in 11 and 2a in 4. The mean plasma HCV-RNA was 728.3 kU/mL and alanine aminotransferase was 107.5 U/L. Granulocyte and monocyte apheresis was with the Adacolumn, which contains carriers that adsorb granulocytes and monocytes/macrophages. After five consecutive granulocyte and monocyte apheresis sessions over 5 days, interferon daily 6 million units for 4 weeks, then three times/week for 20 weeks+ribavirin (600-800 mg per patient per day) were given and followed for another 24 weeks. RESULTS: During granulocyte and monocyte apheresis, plasma HCV-RNA transiently fell by up to 55%. Similarly, incubation of blood with the Adacolumn carriers caused a significant fall in HCV-RNA. Four patients were unavailable for efficacy evaluation. In the other 11, alanine aminotransferase normalised and at 11 weeks, plasma HCV-RNA was negative; six of these (55%) maintained their remission during the follow up. CONCLUSION: Granulocyte and monocyte apheresis appears to deplete extra-hepatic hepatitis C virus reservoirs and generate active complement opsonins, which contribute to hepatitis C virus killing. Additional mechanism(s) are also likely and need to be elucidated in future studies with larger cohort of patients.


Subject(s)
Hepatitis C, Chronic/pathology , Hepatitis C, Chronic/therapy , Leukapheresis/methods , Monocytes , Ribavirin/administration & dosage , Adjuvants, Immunologic/administration & dosage , Adult , Aged , Alanine Transaminase/blood , Combined Modality Therapy , Drug Therapy, Combination , Female , Granulocytes , Hepatitis C, Chronic/immunology , Humans , Interferon alpha-2 , Interferon-alpha , Male , Middle Aged , RNA, Viral/analysis , Recombinant Proteins , Viral Load
5.
FEBS Open Bio ; 5: 429-36, 2015.
Article in English | MEDLINE | ID: mdl-26082885

ABSTRACT

The substrate specificity of recombinant human mitochondrial intermediate peptidase (hMIP) using a synthetic support-bound FRET peptide library is presented. The collected fluorescent beads, which contained the hydrolysed peptides generated by hMIP, were sequenced by Edman degradation. The results showed that this peptidase presents a remarkable preference for polar uncharged residues at P1 and P1' substrate positions: Ser = Gln > Thr at P1 and Ser > Thr at P1'. Non-polar residues were frequent at the substrate P3, P2, P2' and P3' positions. Analysis of the predicted MIP processing sites in imported mitochondrial matrix proteins shows these cleavages indeed occur between polar uncharged residues. Previous analysis of these processing sites indicated the importance of positions far from the MIP cleavage site, namely the presence of a hydrophobic residue (Phe or Leu) at P8 and a polar uncharged residue (Ser or Thr) at P5. To evaluate this, additional kinetic analyses were carried out, using fluorogenic substrates synthesized based on the processing sites attributed to MIP. The results described here underscore the importance of the P1 and P1' substrate positions for the hydrolytic activity of hMIP. The information presented in this work will help in the design of new substrate-based inhibitors for this peptidase.

6.
Int J Biochem Cell Biol ; 32(11-12): 1161-72, 2000.
Article in English | MEDLINE | ID: mdl-11137456

ABSTRACT

A prolyl endopeptidase (PE) was purified 83 times from human urine by DEAE-cellulose and Sepharose Mercurial chromatographies. In this work we studied the specificity of PE using different fluorogenics substrates. Further characterization of the enzyme was carried out using BK and it's analogue, Abz-RPPGFSPFRQ-EDDnp and Abz-FPQ-EDDnp, for measure of enzymatic activity of prolyl endopeptidase (Abz=ortho-aminobenzoic acid; EDDnp=N-[2, 4-dinitrophenyl]ethylenediamine). The substrate Abz-FPQ-EDDnp was considered as specific for PE. The endopeptidase PE, with a molecular weight of 45 kDa, was inhibited 100% by EDTA and pOHMB and resistant to PMSF, thyorphan, E64 and phosphoramidon, when we used the mentioned substrates. These results suggest that PE is a metallo endopeptidase that contains a thiol group important for it's activity. It was also able to hydrolyze in Abz-RPPGFSPFRQ-EDDnp the F-R peptide bound, differing from those obtained upon BK molecule, where the enzyme prefer the peptide bound located after double proline. In the substrate Abz-FPQ-EDDnp PE hydrolyzes the P-Q peptide bound. Furthermore the urinary PE is particularly unable to hydrolyze peptides with single prolines such as substance P, neurotensin and LHRH. The determined K(m) for Abz-RPPGFSPFRQ-EDDnp and Abz-FPQ-EDDnp were 0.74 and 0.65 uM, respectively. The optimum pH for the PE activity, using the substrate Abz-RPPGFSPFRQ-EDDnp was approximately 9.0, but using the specific substrate Abz-FPQ-EDDnp was 6.5 and 8.0. Endopeptidases, which are situated at brush border surface from proximal tubules, have an important role in kidney handling of many peptides, which are filtered by the glomerulus. The prolyl endopeptidase located at distal tubule could have an important physiological function in control of kinin formed in this portion. It's known that all components from kallicrein-kinin system like low molecular weigh kininogen and kallikrein are presents in this portion.


Subject(s)
Serine Endopeptidases/urine , Bradykinin/analogs & derivatives , Bradykinin/metabolism , Chromatography, Agarose , Chromatography, DEAE-Cellulose , Chromatography, High Pressure Liquid , Fluorescent Dyes/metabolism , Humans , Hydrogen-Ion Concentration , Hydrolysis , Kinetics , Oligopeptides/metabolism , Prolyl Oligopeptidases , Protease Inhibitors/pharmacology , Serine Endopeptidases/isolation & purification , Serine Endopeptidases/metabolism , Substrate Specificity
7.
Int J Biochem Cell Biol ; 36(10): 1933-44, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15203108

ABSTRACT

In this study, we compared the properties of a serine endopeptidase H1 (SH1) and a serine thiol endopeptidase (STH2) purified from human urine by DEAE-cellulose followed by a Bio Gel A0.5 m or Sepharose Mercurial chromatographs. These enzymes differ in their action upon different hormone peptides. We used fluorogenic substrates to further characterize the enzyme. The substrate specificity of urinary SH1 was studied using different internally quenched fluorescent peptides, and AbzFGQEDDnp was hydrolyzed by SH1. Other enzymes present in urine, such as serine endopeptidase H2, prolyl endopeptidase, neutral endopeptidase like and angiotensin-I converting enzyme, were not able to hydrolyze this substrate. SH1 is 100% inhibited by PMSF and resistant to EDTA, OPA, thiorphan, E64, pOHMB and phosphoramidon. Endopeptidase STH2 is completely inhibited by PMSF, E64 and pOHMB. Enzyme SH1 hydrolyzes the peptide bound F5-S6 at bradykinin (BK: RPPGFSPFR) molecule and R-Q at AbzBKQEDDnp. When studying enzyme STH2, the cleavage sites determined to the related substrates were F5-S6 using BK as substrate and F-R using AbzBKQEDDnp. The kilometers value obtained for AbzBKQEDDnp and AbzFGQEDDnp were 1.18 and 0.007 uM, respectively. Kininases from kidney and urine can hydrolyze peptide bounds from components of the kallikrein-kinin system, the angiotensin-renin system and the neuropeptides system, straight contributing in kidney homeostasis. SH1 was located at the distal tubule [Casarini et al., 1999a, Am. J. Physiol. 277, F66] and can have an important function in the control of kinin found in this portion, since is known that all components of the kallikrein-kinin system were found in this portion. The physiological role of SHT2 could be related to the inter-relation between the kallikrein-kinin system and neuropeptides in the control of the water electrolyte balance [Braz. J. Med. Biol. Res. 25 (3) (1992) 219].


Subject(s)
Serine Endopeptidases/isolation & purification , Serine Endopeptidases/urine , Amino Acid Sequence , Humans , Hydrogen-Ion Concentration , Kinetics , Molecular Sequence Data , Serine Endopeptidases/metabolism , Substrate Specificity
8.
Int J Biochem Cell Biol ; 33(1): 75-85, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11167134

ABSTRACT

Angiotensin I-converting enzyme (ACE) activity was analyzed in human urine collected from mild hypertensive untreated patients. DEAE-cellulose chromatography using linear gradient elution revealed two forms of angiotensin I-converting enzyme, eluted in the conductivity of 0.75 and 1.25 mS. The fractions of each conductivity were pooled and submitted to direct gel filtration in an AcA-34 column, and the apparent molecular weights of urinary ACEs were estimated as 90 kDa (for ACE eluted in 0.75 mS) and 65 kDa (for ACE eluted in 1.25 mS). Both enzymes have a K(i) of the order of 10(-7) M for the specific inhibitors studied, and are able to hydrolyze luteinizing hormone-releasing hormone and N-acetyl-Ser-Asp-Lys-Pro as described for N-domain ACE. By Western blot analysis, both peaks were recognized by ACE-specific antibody Y4, confirming the molecular weight already described. A plate precipitation assay using monoclonal antibodies to the N-domain of ACE showed that both forms of ACE binds with all monoclonal antibodies to the active N-domain ACE, suggesting that these forms of human urine ACEs resemble the N-fragment of ACE. The HP2 ACE (65 kDa) is similar to low molecular weight (LMW) ACE from normal subjects, and the HP2 ACE (90 kDa) is different from high molecular weight (190 kDa) and LMW (65 kDa) normal ACEs. The 90 kDa ACE could have an important role in development of hypertension. It will be fundamental to elucidate the molecular mechanism responsible for the genesis of this isoform.


Subject(s)
Hypertension/metabolism , Hypertension/urine , Peptidyl-Dipeptidase A/chemistry , Peptidyl-Dipeptidase A/urine , Amino Acid Sequence , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/metabolism , Blotting, Western , Chromatography, DEAE-Cellulose , Chromatography, Gel , Electrophoresis, Polyacrylamide Gel , Humans , Hydrolysis , Kinetics , Molecular Sequence Data , Protein Isoforms , Protein Structure, Tertiary
9.
Arch Neurol ; 45(5): 526-9, 1988 May.
Article in English | MEDLINE | ID: mdl-3358705

ABSTRACT

Central and peripheral nerve conduction was studied in two patients with subacute combined degeneration by using the short-latency somatosensory evoked potentials and the peripheral nerve conduction study during treatment with cyanocobalamin. Before the treatment, somatosensory evoked potentials with median nerve stimulation were normal, but those with peroneal nerve stimulation revealed prolonged central conduction indicating dysfunction within the posterior column. Peripheral sensory and motor nerve action potentials were reduced with normal or slightly reduced conduction velocity. After treatment, marked shortening of the central conduction time (by 24% and 31%, respectively) was observed with mild or no recovery of peripheral nerve action potentials. These physiologic findings suggest that the main pathologic changes in the central nervous system may be demyelination in the posterior column in addition to axonal degeneration in the peripheral nerve. The former was responsive to treatment but the latter was poorly responsive to treatment. Sensory symptom in subacute combined degeneration appears to be, at least partially, attributed to the spinal cord lesion.


Subject(s)
Central Nervous System/physiopathology , Evoked Potentials, Somatosensory , Neural Conduction , Peripheral Nerves/physiopathology , Spinal Cord Diseases/physiopathology , Adolescent , Adult , Aged , Female , Humans , Median Nerve/physiopathology , Middle Aged , Peroneal Nerve/physiopathology , Spinal Cord Diseases/drug therapy , Vitamin B 12/therapeutic use
10.
Mol Biochem Parasitol ; 116(2): 109-15, 2001 Sep 03.
Article in English | MEDLINE | ID: mdl-11522344

ABSTRACT

We have isolated and purified two cysteine proteinases of molecular weights 25 and 26 kDa, secreted by Fasciola hepatica adult worm. Their 15 N-terminal residues were found to be identical to those of earlier described cathepsin L-like enzymes, isolated from the same source, reported as CL1 and CL2. Radioimmunoassay experiments have shown that these CL1- (25 kDa) and CL2-like (26 kDa) cysteine proteinases mediated kinin release from high molecular weight kininogen (HMWK). Lys-bradykinin (KRPPGFSPFR) was characterized as the kinin released from a synthetic fragment of HMWK from Leu373 to Ile393 (Abz-LGMISLMKRPPGFSPFRSSRI-NH2) labeled with the fluorescent group Abz (ortho-aminobenzoic acid). We examined the activity of CL1- and CL2-like on internally quenched fluorescent peptides containing HMWK sequences, in which Met379-Lys380 or Arg389-Ser390 bonds were present in the middle of the molecules. These peptides were flanked by the fluorescent donor-acceptor pair Abz and EDDnp (N-[2,4-dinitrophenyl] ethylenediamine). Peptidyl-methylcoumarin amides (MCA) were used to study the substrate specificity requirements. The enzymes presented significantly lower Km values at pH 8.0. The inverse was observed with the kcat values, which were higher at pH 5.0.


Subject(s)
Cysteine Endopeptidases/metabolism , Fasciola hepatica/enzymology , Kallikreins/metabolism , Amides , Amino Acid Sequence , Animals , Cysteine Endopeptidases/genetics , Cysteine Endopeptidases/isolation & purification , Hydrolysis , Kininogen, High-Molecular-Weight/metabolism , Kinins/metabolism , Molecular Sequence Data , Staining and Labeling , Substrate Specificity , ortho-Aminobenzoates
11.
Biomaterials ; 25(13): 2577-83, 2004 Jun.
Article in English | MEDLINE | ID: mdl-14751743

ABSTRACT

For reconstruction and regeneration of hard tissues, scaffold biomaterials with large size pores and high porosity are important, in addition to their roles as supporting frames. To develop a new biodegradable scaffold biomaterial, CO3Ap, which has crystallinity and a chemical composition similar to bone, was synthesized at pH 7.4 and 60 degrees C. Then, the CO3Ap was mixed with a neutralized collagen gel and the CO3Ap-collagen mixtures with different kinds of CO3Ap contents and porosity were lyophilized into sponges. Scanning electron micrography (SEM) observation of CO3Ap-collagen sponges showed favorable pores for cell invasion. Approximately 50-300 microm size pores appeared to continue through the bulk. Higher magnification of the sponge showed a better adhesion between CO3Ap crystals and collagen. X-ray high-resolution microtomography revealed a clear image of the 3D structure of the sponges. The porosity of 0, 70 and 90%(w/w) CO3Ap-collagen sponges was 79.2 +/- 2.8%, 72.6 +/- 2.4% and 48.9 +/- 6.1%, respectively. The 70%(w/w) CO3Ap-collagen sponge appeared to be the most favorable biomaterial from the viewpoint of natural bone properties. Mouse osteoblast MC3T3-E1 cells were cultured in alphaMEM with 10% FCS for 2 weeks. Hematoxylin-eosin staining confirmed osteoblast cells invaded well into the CO3Ap-collagen sponge. These sponges are expected to be used as hard tissue scaffold biomaterials for therapeutic uses.


Subject(s)
Biocompatible Materials , Collagen/chemistry , Tomography, X-Ray/methods , 3T3 Cells , Animals , Cattle , Mice , Microscopy, Electron, Scanning , X-Ray Diffraction
12.
J Heart Lung Transplant ; 11(4 Pt 1): 646-55, 1992.
Article in English | MEDLINE | ID: mdl-1498127

ABSTRACT

Fluosol DA 20% (Fluosol) perfusion was used to protect ischemic donor hearts of mongrel dogs from reperfusion injury. Fifteen orthotopically transplanted hearts, eight in the control group and seven in the Fluosol group, were studied for 3 hours after weaning from cardiopulmonary bypass. Donor hearts were arrested and immersed in 4 degrees C St. Thomas's Hospital Solution for 4 hours. The mean total ischemic time was 323 minutes (range, 298 to 345 minutes). In the Fluosol group, 200 ml of oxygenated Fluosol (37 degrees C; PO2 650 mm Hg; PCO2 35 mm Hg) was infused into the aortic root at approximately 100 ml/min just before aortic unclamping. Coronary sinus blood was analyzed for the MB fraction of creatine kinase, reduced glutathione, and oxidized glutathione. Hemodynamic and biochemical results were obtained at 30 minutes, 1 hour, and 3 hours after bypass. In the control group, during the second 30 minutes of the period after bypass, left ventricular end-diastolic pressure and stroke volume showed progressive deterioration, 54.8% increased (p less than 0.01) and 28.4% decreased (p less than 0.05), respectively. The MB fraction of creatine kinase and oxidized glutathione were increased, and reduced glutathione had declined, from 39.3 to 135.3 IU/L (p less than 0.01), from 28.0 to 33.4 micrograms/ml (p less than 0.05) and from 4.4 to 2.5 micrograms/ml (p less than 0.01), respectively. These parameters failed to recover during the next 2 hours, and massive mitochondrial degeneration was observed by electron microscopy. In the Fluosol group, these parameters maintained their baseline values, and electron microscopy showed well-preserved mitochondria. The data suggested that, in the control group, initial mitochondrial dysfunction was profound, persistent for at least 3 hours, and associated with membrane hyperpermeability, leading to cardiac dysfunction. Oxygenated Fluosol perfusion better preserved cardiac and mitochondrial function.


Subject(s)
Blood Substitutes/pharmacology , Fluorocarbons/pharmacology , Heart Transplantation/physiology , Myocardial Reperfusion Injury/prevention & control , Animals , Bicarbonates , Calcium Chloride , Cardioplegic Solutions , Creatine Kinase/metabolism , Dogs , Drug Combinations , Glutathione/metabolism , Hydroxyethyl Starch Derivatives , Isoenzymes , Magnesium , Mitochondria, Heart/drug effects , Mitochondria, Heart/metabolism , Potassium Chloride , Sodium Chloride , Time Factors
13.
Brain Res ; 368(2): 361-5, 1986 Mar 19.
Article in English | MEDLINE | ID: mdl-3697731

ABSTRACT

Slow negative potential preceding voluntary self-paced middle finger extension, as recorded from scalp electrodes by backward averaging technique, was absent in two patients with dyssynergia cerebellaris myoclonica (Ramsay Hunt syndrome); but present in two patients with cerebellar cortical degeneration. As the main pathological lesion in Ramsay Hunt syndrome is in the dentate nucleus and its efferent pathway, the present results are in conformity with the experimental finding that the premotor and motor cortices receive strong inputs from the cerebellar efferent system.


Subject(s)
Cerebellar Ataxia/physiopathology , Cerebellar Cortex/physiopathology , Movement , Myoclonic Cerebellar Dyssynergia/physiopathology , Volition , Adolescent , Adult , Electroencephalography , Electromyography , Female , Humans , Membrane Potentials , Middle Aged , Nerve Degeneration
14.
J Gastroenterol ; 29(6): 703-9, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7874263

ABSTRACT

The lysosomal membrane encloses numerous hydrolytic enzymes and prevents the cytoplasm from being damaged by these enzymes. It is possible that the fragility of this membrane may be implicated in the pathogenesis of gastric mucosal damage. We investigated the effects of 16,16-dimethyl prostaglandin E2 (dmPGE2), which is known to protect the gastric mucosa from various noxious agents, on lysosomal membrane stability in the rat stomach. Sodium taurocholate (TC) was used as the damaging agent. To assess lysosomal membrane stability in the gastric mucosa, we assayed acid phosphatase released from lysosomes isolated from a gastric mucosal homogenate. To assess lysosomal membrane stability in gastric surface epithelial cells, we used laser scanning confocal microscopy to observe the fading of red fluorescence in living cells vitally stained with acridine orange. Exogenous dmPGE2 enhanced lysosomal membrane stability in the gastric mucosa, whereas TC decreased it. In gastric surface epithelial cells, exogenous dmPGE2 protected the cells against TC-induced damage and prevented TC-induced decreased lysosomal membrane stability. It was concluded that a decrease in lysosomal membrane stability seemed to be closely involved in the pathogenesis of gastric mucosal damage. Moreover, it appears that stabilization of the lysosomal membrane by exogenous dmPGE2 may contribute to its protective effect in the gastric mucosa, both at the level of gastric surface epithelial cells and in regard to the entire gastric mucosa.


Subject(s)
Prostaglandins E, Synthetic/pharmacology , Stomach/drug effects , Acid Phosphatase/metabolism , Animals , Cell Survival/drug effects , Epithelial Cells , Epithelium/drug effects , Epithelium/metabolism , Gastric Mucosa/drug effects , Gastric Mucosa/metabolism , Intracellular Membranes/drug effects , Intracellular Membranes/metabolism , Lysosomes/drug effects , Lysosomes/metabolism , Male , Microscopy, Confocal , Rats , Rats, Wistar , Stomach/cytology , Taurocholic Acid/pharmacology
15.
J Gastroenterol ; 35(2): 163-7, 2000.
Article in English | MEDLINE | ID: mdl-10680674

ABSTRACT

Acquired ileal diverticulum is an uncommon condition and diagnosis is often difficult when bleeding occurs from this source. Here we describe two cases of ileal diverticulum with massive bleeding. Both patients presented with anal bleeding, but upper and lower gastrointestinal endoscopy did not reveal the source. Selective visceral angiography finally detected bleeding lesions in the terminal ileum. Surgical resection was performed in both patients, confirming that the bleeding arose from diverticula less than 1 cm in size. In patients with obscure gastrointestinal bleeding, an ileal diverticulum should be considered, and selective visceral angiography should be performed for precise diagnosis.


Subject(s)
Diverticulum/complications , Gastrointestinal Hemorrhage/etiology , Ileal Diseases/complications , Aged , Angiography , Colonoscopy , Diagnosis, Differential , Diverticulum/diagnostic imaging , Diverticulum/pathology , Diverticulum/surgery , Gastrointestinal Hemorrhage/diagnostic imaging , Gastrointestinal Hemorrhage/pathology , Gastrointestinal Hemorrhage/surgery , Humans , Ileal Diseases/diagnostic imaging , Ileal Diseases/pathology , Ileal Diseases/surgery , Male , Middle Aged
16.
J Gastroenterol ; 32(5): 605-10, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9349985

ABSTRACT

Intestinal epithelial cells produce various inflammatory mediators. However, the way in which immunosuppressive agents influence the production of these mediators by intestinal epithelial cells is not understood. The effects of cyclosporine A (CsA), tacrolimus (FK506), and dexamethasone (DEX) on cytokine-induced production of interleukin (IL)-8 in a human colonic cancer cell line (HT-29) were examined. HT-29 cells were stimulated with either IL-1 beta or tumor necrosis factor alpha (TNF alpha) together with CsA, FK506, or DEX. The presence of IL-8 protein was detected by enzyme-linked immunosorbent assay, and the expression of IL-8 messenger RNA (mRNA) by reversetranscription polymerase chain reaction. CsA (1, 5, and 10ng/ml) significantly reduced IL-1 beta-induced IL-8 production (by 32%, 41%, and 48%, respectively), and reduced TNF alpha-induced IL-8 production (by 21%, 42%, and 50%, respectively). FK506 or DEX had no effect on IL-1 beta- or TNF alpha-induced IL-8 production. The expression of IL-8 mRNA was also inhibited by CsA. These findings suggest that CsA may influence the production of inflammatory mediators in colonic cells in a different manner from FK506 and DEX.


Subject(s)
Cyclosporine/pharmacology , HT29 Cells/drug effects , Immunosuppressive Agents/pharmacology , Interleukin-8/antagonists & inhibitors , Cell Count/drug effects , Cell Survival/drug effects , Dexamethasone/pharmacology , Enzyme-Linked Immunosorbent Assay , HT29 Cells/metabolism , HT29 Cells/pathology , Humans , Interleukin-1/pharmacology , Interleukin-8/biosynthesis , Interleukin-8/genetics , Polymerase Chain Reaction , RNA, Messenger/biosynthesis , RNA, Messenger/drug effects , Tacrolimus/pharmacology , Tumor Necrosis Factor-alpha/pharmacology
17.
Clin Chim Acta ; 189(3): 267-74, 1990 Aug 31.
Article in English | MEDLINE | ID: mdl-2225459

ABSTRACT

We have developed a new immunochemical test for fecal occult blood utilizing enzyme-linked immunosorbent assay (ELISA) of human hemoglobin (HbAo) and transferrin (Tf) simultaneously. The ELISA had a sensitivity of about 15 ng/ml Hb, and the measurable range was 1.5-750 micrograms Hb per g feces. The stability of Tf in feces was greater than that of Hb. In 17 out of 18 patients with colon cancer, 8 out of 15 patients with colon polyps, and 11 out of 20 patients with upper-gastrointestinal disorders. The Hb and Tf values were more than 10 micrograms/g feces, in terms of Hb concentration. The ELISA for human fecal HbAo and Tf might be useful for the diagnosis of gastrointestinal disorders.


Subject(s)
Occult Blood , Animals , Antibodies, Monoclonal , Antibody Specificity , Cattle , Enzyme-Linked Immunosorbent Assay , Erythrocytes/physiology , Feces/chemistry , Hemoglobins/analysis , Humans , Immunoenzyme Techniques , Plasma , Transferrin/analysis
18.
Biophys Chem ; 73(3): 217-25, 1998 Jul 27.
Article in English | MEDLINE | ID: mdl-17029728

ABSTRACT

Ortho-aminobenzoic acid (o-Abz) has been used as a fluorescent probe in internally quenched fluorescent peptides for continuous protease assays. We investigated the fluorescent properties of the probe in order to verify if it can be used to monitor the interaction of peptides with micelles. Abz-aminoacyl-monomethyl amides (Abz-Xaa-NHCH(3), where Xaa=Arg, Phe, Leu and Glu) were synthesized. Quantum yield, spectral position, anisotropy and lifetime decay were analyzed in the presence and absence of sodium dodecyl sulfate (SDS) micelles. Significant changes in the fluorescence parameters were observed for Abz-Arg-NHCH(3) in comparison to Abz-Glu-NHCH(3), indicating a strong electrostatic component in the compound's interaction with the negative charged micelles. The change in fluorescence parameters, observed when the probe is bound to hydrophobic amino acids Abz-Phe-NHCH(3) and Abz-Leu-NHCH(3), is probably due to insertion of those compounds into micelles. Abz-NHCH(3) fluorescence is less affected by the presence of micelles, indicating that the occurrence of interaction is dependent on the properties of the amino acid to which the fluorophore is attached. The quenching data with acrylamide confirmed these results. Titration curves allowed the estimation of association constants between Abz compounds and SDS, according to a single partition model. Although the results cannot be strictly applied to the titration with charged compounds, it was verified that the association constant for the isolated Abz-NHCH(3) is significantly lower than those for Abz-Phe-NHCH(3) and Abz-Leu-NHCH(3). It is concluded that the Abz group is a sensitive and convenient fluorescent probe to monitor peptide binding to amphiphilic aggregates. That conclusion is supported by measurements with the peptide Abz-Leu-Arg-Phe-NH(2).

19.
Oncol Rep ; 7(4): 841-6, 2000.
Article in English | MEDLINE | ID: mdl-10854555

ABSTRACT

The combination of 5-fluorouracil (5-FU) and cisplatin is used most commonly for gastric carcinoma. Recent studies have indicated that vascular endothelial growth factor (VEGF) is related to drug delivery through angiogenesis and vascular permeability. In this study, we evaluated the efficacy and toxicity of continuous infusion of 5-FU and low dose cisplatin infusion as first-line treatment in patients with unresectable gastric adenocarcinoma. We also examined the relationship between chemotherapy response and immunohistochemical expression of VEGF in the biopsy samples of gastric primary. All 30 patients enrolled in this study were assessable for response, adverse reactions, and VEGF expression. The regimen consisted of 5-FU (350 mg/m2/day every day by continuous venous infusion) and low dose cisplatin (7 mg/m2/day by drip infusion over 1 h on days 1-5 every week). This treatment was repeated weekly for 3 consecutive weeks. Four weeks after the second cycle, mesurable lesions were estimated for response. An overall response rate was 46.7% (14/30). Patients with intestinal histologic type (10/12) and good performance status ([PS], 13/18) showed good response rate (83.3%, and 72.2%, respectively) compared to patients with diffuse histologic type (4/18) and poor PS [(1/12) 22.2%, and 8. 3%, respectively]. The response rate of VEGF-positive cases and VEGF-negative cases was 75% (12/16), and 16.7% (2/14), respectively. Multivarite analysis revealed that VEGF-positive and good PS had a significant impact on chemotherapy response in this treatment. The most common garde 3 or higher toxicities were myelosuppression (30%) and diarrhea (13.3%). Continuous infusion of 5-FU and low dose cisplatin infusion is an effective treatment for patients with unresectable gastric carcinoma, and VEGF expression may be a useful predictor of chemotherapy response in this regimen.


Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Endothelial Growth Factors/analysis , Lymphokines/analysis , Stomach Neoplasms/drug therapy , Adenocarcinoma/mortality , Adenocarcinoma/pathology , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Biopsy , Cisplatin/administration & dosage , Female , Fluorouracil/administration & dosage , Humans , Immunohistochemistry , Infusions, Intravenous , Male , Middle Aged , Multivariate Analysis , Predictive Value of Tests , Stomach Neoplasms/mortality , Stomach Neoplasms/pathology , Survival Rate , Time Factors , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
20.
Anticancer Res ; 19(3B): 2361-4, 1999.
Article in English | MEDLINE | ID: mdl-10472356

ABSTRACT

A total of 781 non-polypoid colorectal neoplasias harvested at 4 main Hospitals in Tokyo, Japan (n = 420) and at 4 different time-intervals at the Karolinska Hospital, Stockholm, Sweden (n = 361) were reviewed. By applying strict histologic definitions, the lesions were classified into adenomas with low grade dysplasia (LGD), with high grade dysplasia (HGD), intramucosal carcinomas (IMC) or submucosal carcinomas (SMC). Of the non-polypoid neoplastic lesions reviewed in Sweden, 82.8% (n = 299) had LGD. In Japanese patients only 42.6% (n = 179) had LGD (p < or = 0.001). On the other hand, as many as 42.4% (n = 178) of the non-polypoid lesions in Japanese patients had HGD, but only 14.1% (n = 51) of those in Swedish patients (p < or = 0.001). Whereas 15.0% (n = 63) of the non-polypoid neoplasias seen in Japan were IMC or SMC, only 3.0% (n = 11) of those seen in Sweden were IMC or SMC (p < or = 0.001). The cause(s) for these differences remains unclear. In Japan, however, a marked increased incidence of colonic cancer has been recorded in later years. Whether the "catching up phenomenon" by the Japanese with western colonic cancer incidence includes increased histologic aggressiveness of non-polypoid neoplastic polyps--as found in this survey--remains to be elucidated.


Subject(s)
Adenoma/pathology , Colonic Neoplasms/pathology , Colorectal Neoplasms/pathology , Intestinal Mucosa/pathology , Adenoma/classification , Colonic Neoplasms/classification , Colonic Neoplasms/epidemiology , Colonic Polyps/classification , Colonic Polyps/epidemiology , Colonic Polyps/pathology , Colorectal Neoplasms/classification , Cross-Cultural Comparison , Humans , Incidence , Japan/epidemiology , Retrospective Studies , Sweden/epidemiology
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