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1.
Kyobu Geka ; 57(9): 901-4, 2004 Aug.
Article in Japanese | MEDLINE | ID: mdl-15366580

ABSTRACT

We report a case of the mediastinal teratoma associated with acute cardiac tamponade followed by emergency operation. This tumor causes a variety of complications, but reports of acute cardiac tamponade have been rare. 20-year-old male admitted into our hospital with complaint of the chest pain, who was diagnosed with mediastinal tumor. She was admitted due to sudden fever up, and 5 days after admission, the complaint of severe epigastralgia and abdominal swelling were occurred. A chest X-ray film and chest computed tomography (CT) revealed cardiac tamponade. We carried out emergency surgical pericardial drainage and extirpation of the tumor. The tumor was composed of cystic part involving of dark green fluid macroscopically. The amylase level in this fluid was 42 U/l. We observed a small hole on the pericardial sac beside the base of ascending aorta. The amylase level in pericardial effusion was 19 U/l. Histopathological diagnosis was mature teratoma perforating into pericardiac sac, which included skin, bronchus and pancreatic tissue. We concluded that the progress of the tumor and the mechanical inflammation were major cause of perforation of the tumor into the pericardial sac, and autodigestion by enzyme from pancreas was minor cause of perforation.


Subject(s)
Cardiac Tamponade/etiology , Mediastinal Neoplasms/complications , Teratoma/complications , Acute Disease , Adult , Cardiac Tamponade/surgery , Female , Humans , Mediastinal Neoplasms/pathology , Rupture, Spontaneous/complications , Teratoma/pathology
2.
Life Sci ; 65(22): 2417-26, 1999.
Article in English | MEDLINE | ID: mdl-10597896

ABSTRACT

The 90 kDa heat shock protein (Hsp90) induces the condensation of the chromatin structure [Csermely, P., Kajtár, J., Hollósi, M., Oikarinen, J., and Somogyi, J. (1994) Biochem. Biophys. Res. Commun. 202, 1657-1663]. In our present studies we used surface plasmon resonance measurements to demonstrate that Hsp90 binds histones H1, H2A, H2B, H3 and H4 with high affinity having dissociation constants in the submicromolar range. Strong binding of the C-terminal peptide of histone H1 containing the SPKK-motif and a pentaeicosa-peptide including the Hsp90 bipartite nuclear localization signal sequence was also observed. However, a lysine/arginine-rich peptide of casein, and the lysine-rich platelet factor 4 did not display a significant interaction with Hsp90. Histones and positively charged peptides modulated the Hsp90-associated kinase activity. Interactions between Hsp90, histones, and high mobility group (HMG) protein-derived peptides raise the possibility of the involvement of Hsp90 in chromatin reorganization during steroid action, mitosis, or after cellular stress.


Subject(s)
HSP90 Heat-Shock Proteins/metabolism , Histones/metabolism , Peptides/metabolism , Amino Acid Sequence , Animals , Enzyme Activation , High Mobility Group Proteins/metabolism , Kinetics , Molecular Sequence Data , Peptide Fragments/metabolism , Protein Kinases/metabolism , Rats , Surface Plasmon Resonance
3.
Plant J ; 19(1): 55-64, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10417726

ABSTRACT

Rice blast, caused by the fungal pathogen Magnaporthe grisea, is one of the most serious diseases of rice. Here we describe the isolation and characterization of Pib, one of the rice blast resistance genes. The Pib gene was isolated by a map-based cloning strategy. The deduced amino acid sequence of the Pib gene product contains a nucleotide binding site (NBS) and leucine-rich repeats (LRRs); thus, Pib is a member of the NBS-LRR class of plant disease resistance genes. Interestingly, a duplication of the kinase 1a, 2 and 3a motifs of the NBS region was found in the N-terminal half of the Pib protein. In addition, eight cysteine residues are clustered in the middle of the LRRs, a feature which has not been reported for other R genes. Pib gene expression was induced upon altered environmental conditions, such as altered temperatures and darkness.


Subject(s)
Carrier Proteins/genetics , Leucine/metabolism , Magnaporthe/pathogenicity , Nucleotides/metabolism , Oryza/microbiology , Plant Proteins , Amino Acid Sequence , Base Sequence , Carrier Proteins/chemistry , Carrier Proteins/metabolism , Cloning, Molecular , Contig Mapping , Cosmids , DNA Primers , DNA, Complementary , Genetic Complementation Test , Molecular Sequence Data , Phosphate-Binding Proteins , Protein Binding , Sequence Homology, Amino Acid , Transcription, Genetic
4.
J Immunol ; 163(3): 1258-64, 1999 Aug 01.
Article in English | MEDLINE | ID: mdl-10415022

ABSTRACT

CD44 is a transmembrane glycoprotein involved in various cell adhesion events, including lymphocyte migration, early hemopoiesis, and tumor metastasis. To examine the requirements of CD44 for signal delivery through the extracellular domain, we constructed a chimeric CD44 protein fused to the intracellular domain of Fas on its C-terminus. In cells expressing the CD44-Fas fusion protein, apoptosis could be induced by treatment with certain anti-CD44 mAbs alone, especially those recognizing the epitope group d, which has been previously shown to play a role in ligand binding, indicating that ligation of a specific region of the CD44 extracellular domain results in signal delivery. Of note was that appropriate ligation of the epitope h also resulted in the generation of apoptotic signal, although this region was not thought to be involved in ligand binding. In contrast, the so-called blocking anti-CD44 mAbs (epitope group f) that can abrogate the binding of hyaluronate (HA) failed to induce apoptosis even after further cross-linking with the secondary Ab, indicating that a mere mAb-induced oligomerization of the chimeric proteins is insufficient for signal generation. However, these blocking mAbs were instead capable of inhibiting apoptosis induced by nonblocking mAb (epitope group h). Furthermore, a chimeric protein bearing a mutation in the HA binding domain and hence lacking the ability to recognize HA was incapable of mediating the mAb-induced apoptosis, suggesting that the functional integrity of the HA binding domain is crucial to the signal generation in CD44.


Subject(s)
Hyaluronan Receptors/genetics , Recombinant Fusion Proteins/immunology , Signal Transduction/immunology , fas Receptor/genetics , Animals , Antibodies, Blocking/pharmacology , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacology , Apoptosis/genetics , Apoptosis/immunology , Epitopes, T-Lymphocyte/immunology , Humans , Hyaluronan Receptors/immunology , Hyaluronan Receptors/physiology , Hyaluronic Acid/metabolism , Lymphocyte Activation/immunology , Mice , Protein Binding/genetics , Protein Binding/immunology , Recombinant Fusion Proteins/chemical synthesis , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Signal Transduction/genetics , Thymoma , Tumor Cells, Cultured , fas Receptor/physiology
5.
Int Immunol ; 9(4): 627-35, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9138024

ABSTRACT

In the present study, we have established a system where engagement of an adhesion molecule triggers a death signal into cells. L-selectin, which is a well characterized adhesion receptor involved in the initial adhesion between lymphocyte and endothelium, was fused to the intracellular domain of an apoptosis-inducing molecule, Fas. Ligation of the chimeric receptors with a carbohydrate ligand for L-selectin, fucoidin or a mAb that recognizes the lectin domain of L-selectin, induced apoptosis in receptor-expressing cells. However, ligation with an anti-L-selectin mAb reactive with a non-ligand binding site did not induce apoptosis, indicating that stimulation through the lectin domain of L-selectin in the chimeric receptor leads to signal delivery. Upon activation L-selectin shows a unique proteolytic cleavage at the membrane proximal site on the extracellular (EC) domain, of which the significance is also unclear. We found that truncations in the EC domain which abrogate the proteolytic cleavage of L-selectin did not influence induction of apoptosis, suggesting that the cleavage on the EC domain itself is not important for the signaling function of the chimeric receptor. This is the first demonstration that an adhesion signal can be converted to a signal that leads to apoptotic cell death.


Subject(s)
Apoptosis/immunology , L-Selectin/genetics , Receptors, Immunologic/immunology , Receptors, Immunologic/physiology , Recombinant Fusion Proteins/pharmacology , fas Receptor/genetics , Animals , Antibodies, Monoclonal/pharmacology , Apoptosis/drug effects , Cross-Linking Reagents , Humans , Jurkat Cells , L-Selectin/biosynthesis , L-Selectin/immunology , Polysaccharides/metabolism , Protein Binding/drug effects , Protein Structure, Tertiary , Rats , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/chemical synthesis , Sequence Deletion/immunology , fas Receptor/biosynthesis
6.
Epilepsia ; 37(10): 1020-2, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8822703

ABSTRACT

PURPOSE: We report a 1-year 7-month-old boy with severe myoclonic epilepsy in infancy (SME) who exhibited complex partial status epilepticus (CPSE), which was confirmed by ictal video-EEG analysis. This boy first had a hemiconvulsion in a hot bath at age 3 months. Thereafter, he exhibited both partial and generalized seizures that were extremely intractable. At age 9 months, he had a prolonged episode of impaired consciousness that fit the "obtundation status in SME" defined by Dravet et al. METHODS AND RESULTS: Ictal EEG revealed persisting irregular spike-and-wave complexes over the left hemisphere, predominantly in the occipitotemporal area, and confirmed CPSE. The EEG abnormalities with decreased level of the consciousness continued approximately 6 h after onset of the symptoms even with AED administration. CONCLUSIONS: Because SME features both generalized and focal seizures, both types of nonconvulsive status may be seen in SME. Although Dravet et al. already reported long-lasting atypical absences in patients with SME as "obtundation status," we demonstrated CPSE in an infant with SME who exhibited a prolonged stuporous state.


Subject(s)
Coma/etiology , Epilepsies, Myoclonic/etiology , Epilepsy, Complex Partial/complications , Status Epilepticus/complications , Coma/diagnosis , Electroencephalography , Epilepsies, Myoclonic/diagnosis , Humans , Infant , Male , Terminology as Topic , Videotape Recording
8.
Pediatr Neurol ; 13(2): 137-41, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8534278

ABSTRACT

We report 5 pediatric patients (2 male, 3 female; age range: 4-8 years) with complex partial status epilepticus (CPSE). Four patients had previous illnesses and mild motor or mental retardation. In 2 patients, CPSE was induced by inappropriate management or selection of antiepileptic drugs. Clinical features varied and automatisms were observed in 3 patients. In 1 patient, decreased physical tone with syncope and impaired consciousness with amaurosis were observed. The episodes of CPSE were continuous in 3 patients and recurrent in 2 patients. In 4 patients, ictal electroencephalographic (EEG) findings, including video-EEG analyses of 3 patients, demonstrated persistent focal epileptic features. Intravenous diazepam abolished CPSE in 3 patients with brief periods of definite EEG localizations remaining. In 4 patients, seizure prognoses were favorable after appropriate treatments; in 1 patient, seizures were intractable even after antiepileptic drug administration.


Subject(s)
Electroencephalography , Epilepsy, Complex Partial/diagnosis , Status Epilepticus/diagnosis , Anticonvulsants/therapeutic use , Child , Child, Preschool , Diazepam/therapeutic use , Drug Therapy, Combination , Electroencephalography/drug effects , Epilepsy, Complex Partial/drug therapy , Evoked Potentials/drug effects , Female , Humans , Infusions, Intravenous , Male , Neurologic Examination/drug effects , Status Epilepticus/drug therapy
10.
Epilepsia ; 35(4): 823-6, 1994.
Article in English | MEDLINE | ID: mdl-8082629

ABSTRACT

A 4-year-old boy with infantile neuroaxonal dystrophy (INAD) showed gradual deterioration from age 9 months with seizure development at age approximately 36 months. Sural nerve biopsy performed at age 42 months confirmed INAD. The seizure, recorded by video-EEG, consisted of a series of symmetrical tonic spasms of both upper extremities after a prodrome period of staring and akinesis. Each spasm had phonation, and episodic autonomic symptoms such as hypertension and flushing of the face occurred throughout the seizure. Ictal EEG with each tonic spasm, showed diffuse 1-s, irregular sharp and high-voltage slow wave complexes followed by desynchronization.


Subject(s)
Demyelinating Diseases/diagnosis , Electroencephalography/methods , Epilepsy/diagnosis , Videotape Recording , Axons/pathology , Brain/pathology , Child, Preschool , Cortical Synchronization , Demyelinating Diseases/complications , Demyelinating Diseases/pathology , Epilepsy/complications , Humans , Infant , Magnetic Resonance Imaging , Male , Spasms, Infantile/diagnosis , Sural Nerve/pathology
11.
Gan To Kagaku Ryoho ; 21(6): 801-8, 1994 May.
Article in Japanese | MEDLINE | ID: mdl-8185337

ABSTRACT

A multi-institutional early phase II study of KW-2307 (vinorelbine), a new vinca alkaloid derivative, in advanced or recurrent breast cancer was conducted in 15 nationwide hospitals. KW-2307 was intravenously administered once weekly at doses of 15 to 25 mg/m2. Sixty-five among the enrolled 69 patients were eligible. Response rates were 11.8% (2/17) with 15 mg/m2, 28.0% (7/25) with 20 mg/m2 and 17.4% (4/23) with 25 mg/m2, and the overall response rate was 20.0%. Once-weekly intravenous administration of 20 mg/m2 was estimated to be the optimal dose of KW-2307 from the results. The major side effect was leucopenia, which was the dose-limiting factor in this study. Other subjective or objective side effects included anorexia, nausea-vomiting, phlebitis, fever, general fatigue and stomatitis, but none of them was serious.


Subject(s)
Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Neoplasm Recurrence, Local/drug therapy , Vinblastine/analogs & derivatives , Adult , Aged , Anorexia/chemically induced , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Drug Administration Schedule , Female , Humans , Infusions, Intravenous , Leukopenia/chemically induced , Middle Aged , Nausea/chemically induced , Vinblastine/administration & dosage , Vinblastine/adverse effects , Vinblastine/therapeutic use , Vinorelbine
12.
Br J Cancer ; 69(4): 767-71, 1994 Apr.
Article in English | MEDLINE | ID: mdl-8142265

ABSTRACT

A prospective randomised multicentre clinical study was undertaken for 2 years and 3 months from November 1982, with the aim of examining the significance of using a combination of ftorafur (FT) and tamoxifen (TAM) for post-operative adjuvant therapy of breast cancer. Patients had either stage II or stage IIIa disease, were age 75 or below and had undergone radical mastectomy. Patients were divided into two groups and received one of the following treatment protocols: treatment A, intravenous administration of doxorubicin (DOX), 20 mg on the day of surgery and 10 mg the next day, followed by oral FT 50 mg day-1 for 2 years from the 14th day; treatment B, the same pattern of DOX administration for the first 2 days, followed by a combined therapy of FT and TAM 20 mg day-1 for 2 years. The number of patients was 546 (treatment A 274 and treatment B 272), of whom 34 (6%) were ineligible. The remaining 512 patients (treatment A 254 and treatment B 258) were followed up for 5 years for analysis. Significantly higher 5 year disease-free rate and 5 year survival rates were observed with treatment B compared with treatment A. When seen in terms of background factors, node-positive patients appeared to derive more benefit from tamoxifen than node-negative patients, but the oestrogen receptor-negative and premenopausal subgroups appeared to derive about the same benefit as those who were oestrogen receptor positive and post-menopausal. Indeed, survival in the premenopausal group was significantly better with tamoxifen (P = 0.04). No increase in side-effects was seen by combining TAM with FT. The study results demonstrate that concomitant administration of FT and TAM is better than FT alone for post-operative adjuvant therapy for breast cancer.


Subject(s)
Breast Neoplasms/drug therapy , Tamoxifen/therapeutic use , Tegafur/therapeutic use , Adult , Age Factors , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/mortality , Breast Neoplasms/surgery , Chemotherapy, Adjuvant , Chi-Square Distribution , Double-Blind Method , Doxorubicin/administration & dosage , Female , Humans , Mastectomy, Radical , Middle Aged , Postoperative Care , Prospective Studies , Receptors, Estrogen/analysis , Survival Analysis , Survival Rate
13.
Biochem Biophys Res Commun ; 200(2): 808-15, 1994 Apr 29.
Article in English | MEDLINE | ID: mdl-8179615

ABSTRACT

A naturally occurring splice variant of hepatocyte growth factor (HGF) lacks a 5-amino acid sequence in the first kringle domain. Comparison of HGF and the deletion variant (dHGF) revealed that the deletion significantly altered the biological activities, solubility, and immunological property of HGF. HGF was respectively about 20-, 10-, and 2-fold more potent than dHGF in the stimulation of DNA synthesis in human umbilical vein endothelial cells, human aorta smooth muscle cells, and NSF-60 (murine myeloblastic cells). Conversely, dHGF was respectively about 3-, 2-, and 2-fold more potent than HGF in the stimulation of DNA synthesis in LLC-PK1 (pig kidney epithelial cells), OK (American opossum kidney epithelial cells), and rat hepatocytes. Moreover, HGF was over 70-fold more soluble than dHGF in PBS. Several monoclonal antibodies raised against dHGF recognized only dHGF and neither HGF nor reduced dHGF, demonstrating that the deletion caused a tertiary structural change. The structural change in HGF may be responsible for its altered biological activities and solubility.


Subject(s)
Hepatocyte Growth Factor/genetics , Animals , Cell Division/drug effects , Cells, Cultured , DNA/biosynthesis , Hepatocyte Growth Factor/chemistry , Hepatocyte Growth Factor/pharmacology , Humans , Immunochemistry , In Vitro Techniques , Liver/cytology , Liver/drug effects , Liver/metabolism , Mice , Molecular Weight , Protein Structure, Tertiary , Proto-Oncogene Proteins c-met , Rats , Receptor Protein-Tyrosine Kinases/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/pharmacology , Sequence Deletion , Structure-Activity Relationship
14.
Eur J Cancer ; 30A(7): 959-64, 1994.
Article in English | MEDLINE | ID: mdl-7946592

ABSTRACT

The usefulness of CAF [cyclophosphamide (CPA)/doxorubicin (ADR)/5-fluorouracil (5-FU)] + medroxyprogesterone acetate (MPA) therapy for advanced/recurrent breast cancer was studied in a randomised trial at 56 institutions. Patients received CAF therapy [CPA: 100 mg, orally, days 1-14; ADR: 30 mg/m2, intravenously (i.v.), days 1 and 8; 5-FU: 500 mg/m2, i.v., days 1 and 8) in arm I, or CAF + MPA therapy (CAF + MPA 1200 mg, daily) in arm II. The response rate was significantly higher (P = 0.041) in arm II (53.5%, 46/86) than arm I (36.6%, 30/82). The response rate by tumour site was significantly higher for lymph node and bone lesions in arm II. Partial response duration and overall response duration were significantly longer in arm II. Incidences of anorexia and nausea/vomiting were significantly higher in arm I but in arm II, moon face, oedema and vaginal bleeding were significantly higher. Many patients in arm II demonstrated improvement in performance status and weight loss, suggesting a beneficial effect of MPA. The chemoendocrine therapy with CAF + MPA appears to be more beneficial than CAF alone in the treatment of advanced/recurrent breast cancer.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Administration, Oral , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Breast Neoplasms/blood , Breast Neoplasms/mortality , Cyclophosphamide/administration & dosage , Cyclophosphamide/adverse effects , Disease-Free Survival , Doxorubicin/administration & dosage , Doxorubicin/adverse effects , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Humans , Infusions, Intravenous , Leukocyte Count , Medroxyprogesterone Acetate/administration & dosage , Medroxyprogesterone Acetate/adverse effects , Middle Aged , Neoplasm Recurrence, Local , Platelet Count
15.
Nihon Rinsho ; 51(7): 1875-8, 1993 Jul.
Article in Japanese | MEDLINE | ID: mdl-8366612

ABSTRACT

Biliary tree of gastrectomized patients was examined with ultrasonography to investigate the factors affecting post-gastrectomy gallstone formation. Only gallbladder stone was found in 57 (18.9%). In 11 (20.0%) of 55 patients, stones had developed within 2 years after surgery, but no difference in incidence were observed by sex and age. Sixty four gastrectomized gallstone patients were examined in respect to the kind of gallstone. Patients with cholesterol gallstones were 18 (28.1%), patients with black gallstones were 29 (45.3%) and patients with calcium bilirubinate gallstones were 17 (26.6%). The incidence rate of cholesterol gallstones was lower and the rate of black gallstones and calcium bilirubinate gallstones was higher than that of non-gastrectomized patients. In conclusion, the incidence of pigment gallstones is very high in gastrectomized patients.


Subject(s)
Cholelithiasis/etiology , Gastrectomy , Postoperative Complications , Adult , Age Factors , Aged , Bilirubin/analysis , Cholelithiasis/chemistry , Cholesterol/analysis , Female , Humans , Male , Middle Aged , Sex Factors
16.
Gan To Kagaku Ryoho ; 19(7): 1033-9, 1992 Jul.
Article in Japanese | MEDLINE | ID: mdl-1626939

ABSTRACT

A multi-institutional phase II study of DWA2114R was conducted in breast cancer. DWA2114R at doses of 800-1,000 mg/m2 was administered by 1-hour intravenous infusion every 3-4 weeks on minimal two cycles. Fifty-two patients entered the study; 34 were eligible, 7 ineligible. Eleven patients were dropped from evaluation due to incomplete observations. There were 1CR, 6PR, 1MR, 12 NC, and 14 PD with an overall response rate of 20.6%. A median duration of responses was 11 weeks. Leukopenia and nausea/vomiting were frequently observed but well tolerated and recovery was quick. It is concluded that DWA2114R is a useful drug in the treatment of breast cancer.


Subject(s)
Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Carboplatin/analogs & derivatives , Anorexia/chemically induced , Antineoplastic Agents/adverse effects , Carboplatin/adverse effects , Carboplatin/therapeutic use , Drug Administration Schedule , Drug Evaluation , Female , Humans , Infusions, Intravenous , Middle Aged , Nausea/chemically induced , Vomiting/chemically induced
17.
Tohoku J Exp Med ; 165(2): 67-77, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1812595

ABSTRACT

This study was undertaken to investigate the bilirubin clearance, bilirubin conjugation and biliary bilirubin excretion after an intravenous single bilirubin injection (5 mg/kg or 10 mg/kg) in 10 mongrel dogs. Serum total bilirubin concentration increased after the bilirubin injection, and then it immediately decreased. Biliary excretion of loaded bilirubin induced a rapid increase of the bile total bilirubin concentration and bilirubin-monoconjugate. In the 10 mg/kg group, the increase was larger than in the 5 mg/kg group and remained high up to 4 hr after injection, whereas in the 5 mg/kg group these bile components tended to decrease and returned to the preinjection levels within 4 hr. The total bile acid concentration in the bile remained unchanged in both groups. The bile flow did not change in the 5 mg/kg group, but in the 10 mg/kg group it decreased after bilirubin loading. Significantly positive correlations were observed between total bilirubin and bilirubin monoconjugate concentrations in bile both before and 1 hr after injection, but the slopes of regression lines were markedly different from each other. These results suggest that a bilirubin load surpassing the conjugating capacity of the hepatocytes increases bile bilirubin monoconjugate and also enhances the conjugating activity in the liver.


Subject(s)
Bilirubin/metabolism , Animals , Bile/metabolism , Bile/physiology , Bile Acids and Salts/metabolism , Bilirubin/administration & dosage , Bilirubin/pharmacokinetics , Dogs , Injections, Intravenous
19.
FEBS Lett ; 279(2): 253-5, 1991 Feb 25.
Article in English | MEDLINE | ID: mdl-1900472

ABSTRACT

Effects of oligopeptides containing Lys residues on the conformation of poly(dG-m5dC) have been investigated by circular dichroism spectroscopy. Lys-Ala-Lys (KAK) and its longer analogs with Lys-Ala repeats are found to convert the B-form polynucleotide to the Z form very efficiently. The ability to induce the B-Z transition is characteristic of alternating Lys-Ala sequences and increases exponentially with increasing number of the repeats. The heptapeptide KAKAKAK has an ability comparable with that of spermine, one of the most effective inducers hitherto known. The present results provide the first example of the B-Z transition of poly(dG-m5dC) induced by peptide binding.


Subject(s)
DNA-Binding Proteins/metabolism , DNA/chemistry , Lysine/chemistry , Nucleic Acid Conformation , Peptides/chemistry , Polydeoxyribonucleotides/chemistry , Alanine , Amino Acid Sequence , Circular Dichroism , In Vitro Techniques , Molecular Sequence Data , Polydeoxyribonucleotides/metabolism , Structure-Activity Relationship
20.
Am J Pathol ; 137(5): 1103-11, 1990 Nov.
Article in English | MEDLINE | ID: mdl-2240161

ABSTRACT

We report the development of an animal model of multiple necrotizing enteritis (MNE) in rats. When rats were injected directly with a culture supernatant of lipopolysaccharide (LPS)-stimulated rat peritoneal macrophages into the abdominal aorta, the overt pathologic lesions of MNE developed within 30 minutes after injection. The rats showed an elevated level of blood fibrinogen degradation product content even 30 minutes after injection. Furthermore the rats that were pretreated intravenously with heparin sulfate did not develop MNE, indicating the acute disturbances of blood microcirculation in the intestine. Multiple necrotizing enteritis was developed also by the injection with recombinant tumor necrosis factor (rTNF) but rarely was observed with even a high dose of recombinant interleukin-1 (rIL-1) or platelet-activating factor (PAF). The supernatant was cytotoxic in vitro to TNF-susceptible LM and many other cells but was less cytotoxic to the TNF-resistant LR line. Partial purification of the supernatant suggested that the supernatant contained a cytokine that has biochemical features of TNF. Furthermore polyclonal anti-TNF antibody could inhibit not only the cytotoxicity in vitro but also MNE development in vivo by this factor. These data strongly indicate that MNE possibly could be caused by a TNF-like cytokine produced by macrophages that are stimulated by the endotoxin.


Subject(s)
Cytokines/toxicity , Enteritis/pathology , Lipopolysaccharides/pharmacology , Macrophages/physiology , Tumor Necrosis Factor-alpha/toxicity , Animals , Cells, Cultured , Cytokines/biosynthesis , Cytokines/isolation & purification , Disease Models, Animal , Enteritis/chemically induced , Fibrin Fibrinogen Degradation Products/analysis , Interleukin-1/toxicity , Intestines/drug effects , Intestines/pathology , Macrophages/drug effects , Male , Necrosis , Rats , Rats, Inbred Strains , Recombinant Proteins/toxicity
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