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Publication
Journal: Journal of Molecular Microbiology and Biotechnology
August/7/2012
Abstract
BACKGROUND
Leptospiral sphingomyelinases are candidate virulence factors present only in pathogenic Leptospira spp. Leptospira interrogans serovar Lai encodes Sph1, Sph2, Sph3, Sph4 and SphH. Except for Sph4, they all possess the exo-endo-phosphatase domain that groups them under the DNase I superfamily.
CONCLUSIONS
Modeling of exo-endo-phosphatase domains reveals high-level structural similarity of Sph2 with the crystal structure of SmcL and BC SMase sphingomyelinases from Listeria ivanovii and Bacillus cereus, respectively. A β-hairpin loop, essential for host cell membrane interaction, is absent in leptospiral sphingomyelinases. Instead, several aromatic amino acids were oriented outward from the surface of these molecules and formed clusters of hydrophobic regions that possibly enables the anchoring of these molecules into the host cell membrane, as demonstrated in Sph2 and Sph3. Sph2 is unique and possesses the Mg(++)-binding Glu53 residue in the metal-binding site and two His residues (His151 and His286) in the catalytic site. We demonstrate experimentally the Mg(++)-dependent hemolysis of erythrocytes by rSph2 and its ability to cleave sphingomyelin to ceramide. Anti-Sph2 antibodies neutralized the hemolytic activity of Sph2. In conclusion, we provide evidence showing that Sph2 is a Mg(++)-dependent hemolysin with both sphingomyelinase and hemolytic activities.
Publication
Journal: Biochimica et Biophysica Acta - General Subjects
November/12/2008
Abstract
LEI (Leukocyte Elastase Inhibitor), the precursor of the pro-apoptotic molecule L-DNase II, belongs to the ovalbumin subgroup of serpins. Several serpins can inhibit apoptosis: the viral serpin Crm A inhibits Fas or TNFalpha-induced apoptosis, and overexpression of PAI-2 or PI-9 protects cells from TNFalpha or granzyme B induced apoptosis. We have previously shown that LEI overexpression protects cells from etoposide-induced apoptosis. The molecular reason of this anti-apoptotic activity is now investigated. We show that, in BHK-21 and HeLa cells, LEI anti-protease activity is essential for its anti-apoptotic effect. The protease inhibited is cathepsin D, released from the lysosome during etoposide treatment. Cathepsin D enhances caspase activity in the cell by cleaving procaspase-8 and LEI overexpression slows down this cleavage, protecting cells from apoptosis. This let us presume that high expression of LEI in tumor cells may reduce the efficiency of etoposide as a chemotherapeutic agent.
Publication
Journal: Journal of Clinical Investigation
May/2/1985
Abstract
Using a gel overlay technique we have previously described a 90,000-mol wt actin-binding protein in a number of hormone-secreting tissues and tentatively identified this protein as gelsolin. Gelsolin is a protein that cuts or solates cross-linked actin filaments and can also serve as a nucleating site for actin polymerization. The objective of this study was to isolate this protein from a hamster insulin-secreting (HIT) cell line and compare the immunologic properties and peptide maps of purified rabbit macrophage gelsolin, human platelet gelsolin, and the HIT cell 90,000-mol wt protein. DNase I-Sepharose retained the HIT cell actin-binding proteins in 1 mM CaCl2; some of the 90,000-mol wt protein could then be eluted with 1 mM EGTA. The remaining actin-binding proteins were eluted using a buffer containing SDS. The EGTA peak fractions contained two major protein bands of Mr = 90,000 and 42,000, which suggested that a 90,000-mol wt-actin complex was eluted from the DNase I-Sepharose column. Specific antibodies to the human platelet and rabbit macrophage gelsolins bound to the 90,000-mol wt bands in the eluates, but did not crossreact with other actin-binding proteins. Indirect immunofluorescence using an anti-human platelet gelsolin antibody localized the 90,000-mol wt protein to stress fibers that were also stained with phalloidin, which suggested that gelsolin is associated with actin in vivo. Tryptic peptide maps of all three radioiodinated gelsolins were virtually indistinguishable. Thus, gelsolin is a highly conserved gene product found in at least three diverse cell types, an insulin-secreting beta cell line, macrophages, and platelets, and may link a transient increase in Ca2+ cellular levels with changes in actin polymerization and/or the gel-sol state of these cells.
Publication
Journal: Journal of Virological Methods
February/18/1991
Abstract
RNA from IdUrd-treated P3HR1 cells was used for the construction of a cDNA library and screened with BBV DNA BamHI fragment B and G probes. One clone, BG9, containing a 1.7 kb cDNA insert was further studied. Complete DNA sequence analysis revealed that BG9 encompassed the BBV DNA sequences from nucleotide 120,747 to nucleotide 122,412 and corresponded to the BGLF5 open reading frame of the EBV DNase gene. Comparison of the sequences of BG9 with that of published BBV DNA indicated that there were 14 different bases which results in 7 amino acid residue changes. The product of in vitro transcription/translation of a subclone, pGEM-BG9, contained the EBV DNase activity and a 52 kDa protein was immunoprecipitated from the in vitro translation products using serum from a patient with nasopharyngeal carcinoma which contained a high level of anti-DNase activity. Northern hybridization of P3HR1 RNA with the BG9 probe revealed a complex pattern of transcription in this region. Subgenomic DNA fragments were then used to map these RNA species to the BBV DNA sequence. The result of S1 nuclease analysis indicated that a DNase ORF containing transcript sized 2.0 kb is initiated at nucleotide 122,435 +/- 1 and terminated at nucleotide 120,741 of the EBV genome.
Publication
Journal: Mayo Clinic Proceedings
February/29/2000
Abstract
OBJECTIVE
To guide primary care physicians regarding the diagnosis and treatment of poststreptococcal reactive arthritis (PSReA) in adults.
METHODS
We retrospectively reviewed an indexed database of all patients evaluated or hospitalized between 1976 and 1998 at Mayo Clinic Rochester and identified 35 patients with the diagnosis of reactive streptococcal arthritis, arthralgia, or arthritides. Twenty-nine patients with the diagnosis of acute rheumatic fever (ARF), septic streptococcal arthritis, or nonspecific reactive arthritis were excluded.
RESULTS
PSReA was confirmed in 6 adults (3 women, 3 men; age range, 25-66 years). All patients were symptomatic with polyarthritis and oligoarthritis disproportionate to the objective findings on physical examination. Although all patients had negative throat cultures at the onset of arthritis, increased titers of anti-DNase B and antistreptolysin O confirmed recent streptococcal infection. Antecedent events included pharyngitis in 3 patients (who had received a minimum of a 10-day course of penicillin) and toxic shock syndrome in 1 patient. The latency of onset of arthritis ranged from 4 days to 6 weeks. The arthritic symptoms had a protracted course beyond the typical maximum of 3 weeks described for ARF. Treatment with aspirin did not provide symptomatic relief in any of the patients, whereas the response to therapy with nonsteroidal anti-inflammatory drugs (NSAIDs) was at least partial in all cases. Symptomatic relief occurred in 1 patient who received indomethacin and in 1 patient treated with prednisone. Penicillin prophylaxis was recommended in 1 patient.
CONCLUSIONS
PSReA should be included in the differential diagnosis of all adult patients presenting with arthritis. Treatment strategies include aspirin, other NSAIDs, and corticosteroids. In adult patients with PSReA, there is no evidence to support the use of penicillin prophylaxis at this time.
Publication
Journal: Clinical and diagnostic laboratory immunology
May/19/2004
Abstract
The levels of streptococcal antibody titers in populations with or without rheumatic fever from an area with a relatively high incidence of rheumatic fever and an area with a low incidence of this disease were compared. Streptococcal antibody titers were determined for two populations, each of which included children without rheumatic fever (nonrheumatic children) and rheumatic fever patients. The two populations were derived from two separate geographic areas, one with a high incidence of rheumatic fever (Grenada) and another with a low incidence of this disease (central Florida). The results revealed an absence of consistent differences in the geometric mean antibody titers between the nonrheumatic subjects and the rheumatic fever patients from Grenada. In the population from Grenada, the mean anti-streptolysin O and anti-DNase B titers were higher in the nonrheumatic controls (P of 0.085 and 0.029, respectively). However, the mean titer of the antibody to the group A streptococcal cell wall carbohydrate was higher in the rheumatic fever patients than in the nonrheumatic controls (P = 0.047). This finding contrasted with the finding that the means of all three streptococcal antibody titers in the patients with rheumatic fever were significantly higher than those in the nonrheumatic subjects from Florida (P = 0.01-<0.001). The reason for this paradoxical finding became evident when the streptococcal antibody titers of the nonrheumatic subjects from Grenada and Florida were compared, revealing significantly higher levels of all three antibodies in the nonrheumatic subjects from Grenada than in the nonrheumatic subjects from Florida (P < 0.001). These results suggest that nonrheumatic individuals in an area with a high incidence of rheumatic fever have inordinately elevated levels of streptococcal antibodies in serum. The presence of elevated streptococcal antibody titers in such a population, which probably reflects a high background prevalence of streptococcal infections, should be taken into consideration when evaluating the role of the group A streptococcus in nonpurulent complications of infections.
Publication
Journal: Journal of Biological Chemistry
August/12/1998
Abstract
The ability of recombinant human DNase I (DNase I) to degrade DNA to lower molecular weight fragments is the basis for its therapeutic use in cystic fibrosis (CF) patients and its potential use as a treatment for systemic lupus erythematosus (SLE). To increase the potency of human DNase I, we have generated and characterized three classes of mutants: (a) hyperactive variants, which have from one to six additional positively charged residues (+1 to +6) and digest DNA much more efficiently relative to wild type, (b) actin-resistant variants, which are no longer inhibited by G-actin, a potent inhibitor of DNase I, and (c) combination variants that are both hyperactive and actin-resistant. For DNA scission in CF sputum where the DNA concentration and length are large, we measured a approximately 20-fold increase in potency relative to wild type for the +3 hyperactive variant Q9R/E13R/N74K or the actin-resistant variant A114F; the hyperactive and actin-resistant combination variant was approximately 100-fold more potent than wild type DNase I. For digesting lower concentrations of DNA complexed to anti-DNA antibodies in human serum, we found a maximal enhancement of approximately 400-fold over wild type for the +2 variant E13R/N74K. The +3 enzymes have approximately 4000-fold enhancement for degrading moderate levels of exogenous DNA spiked into human serum, whereas the +6 enzyme has approximately 30,000-fold increased activity for digesting the extremely low levels of endogenous DNA found in serum. The actin resistance property of the combination mutants further enhances the degree of potency in human serum. Thus, the human DNase I variants we have engineered for improved biochemical and pharmacodynamic properties have greater therapeutic potential for treatment of both CF and SLE.
Publication
Journal: Arthritis research & therapy
November/13/2018
Abstract
BACKGROUND
In systemic sclerosis (SSc), autoantibodies provide the most accurate tool to predict the disease subset and pattern of organ involvement. Scleroderma autoantibodies target nucleic acids or DNA/RNA-binding proteins, thus SSc immune complexes (ICs) can embed nucleic acids. Our working hypothesis envisaged that ICs containing scleroderma-specific autoantibodies might elicit proinflammatory and profibrotic effects in skin fibroblasts.
METHODS
Fibroblasts were isolated from skin biopsies obtained from healthy subjects and patients with diffuse cutaneous SSc (dcSSc). ICs were purified by polyethylene-glycol precipitation from sera of SSc patients bearing different autoantibodies. ICs from patients with systemic lupus erythematosus (SLE) and primary anti-phospholipid syndrome (PAPS) and from normal healthy subjects (NHS) were used as controls. After incubation with ICs, fibroblasts were evaluated for ICAM-1 expression, interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1, matrix metalloproteinase (MMP)-2, tumor growth factor (TGF)-ββ and endothelin-1 mRNA, and NFκB, p38MAPK and SAPK-JNK activation rate. Experiments were also performed after pretreatment with DNase I/RNase and NFκB/p38MAPK inhibitors.
RESULTS
The antigenic reactivity for each SSc-IC mirrored the corresponding serum autoantibody specificity, while no positivity was observed in NHS-ICs or sera. SSc-ICs but not NHS-ICs increased ICAM-1 expression, stimulated IL-6, IL-8, MMP-2, MCP-1, TGF-ββ, tlr2, tlr3 and tlr4, and activated NFκB, p38MAPK and SAPK-JNK. tlr9 was significantly upregulated by ARA-ICs, mmp-1 was significantly induced by ACA-ICs whereas colIα1 was not modulated by any SSc-ICs. SLE-ICs and PAPS-ICs significantly upregulated MMP-2 and activated NFκB, p38MAPK and SAPK-JNK. SLE-ICs and PAPS-ICs did not affect colIα1, mmp-1 and Pro-CollagenIα1. DNase I and RNase treatment significantly reduced the upregulation of study mediators induced by SSc-ICs. Pretreatment with NFκB/p38MAPK inhibitors suggested that response to anti-Th/To-ICs was preferentially mediated by p38MAPK whereas ATA-ICs, ACA-ICs and ARA-ICs engaged both mediators. In dcSSc fibroblasts, stimulation with SSc-ICs and NHS-ICs upregulated IL-6 and IL-8.
CONCLUSIONS
These data provide the first demonstration of the proinflammatory and profibrotic effects of SSc-ICs on fibroblasts, suggesting the potential pathogenicity of SSc autoantibodies. These effects might be mediated by Toll-like receptors via the interaction with nucleic acid fragments embedded in SSc-ICs.
Publication
Journal: Journal of Diabetes
December/28/2018
Abstract
<A<em>b</em>stractText>The aim of this study was to investigate the association of the formation of neutrophil extracellular traps (NETs) with gut leakage in type 1 (T1D) and type 2 dia<em>b</em>etes (T2D).</A<em>b</em>stractText><p><div>(<em>b</em>)METHODS</<em>b</em>)</div>In all, 105 su<em>b</em>jects (56 T1D, 49 T2D) were included in the study. Eight <em>b</em>iomarkers of NET formation and gut leakage (ie, protein arginine deiminase type 4 [PAD4], neutrophil elastase [NE], proteinase 3 [PR3], complement 5a [C5a], α<su<em>b</em>)1</su<em>b</em>) -<em>anti</em>trypsin [AAT], <em>DNase</em> I, zonulin, and lipopolysaccharide [LPS]) were measured in serum samples <em>b</em>y ELISA. Neutrophils were isolated and stimulated <em>b</em>y phor<em>b</em>ol myristate acetate to form NETs in vitro. Neutrophil intracellular contents were then collected and used as <em>anti</em>gens to detect <em>anti</em>-neutrophil cytoplasmic <em>anti</em><em>b</em>odies (ANCA) in the serum.</p><A<em>b</em>stractText>There was an increase in NET-associated proteins (PAD4, NE, PR3, C5a, AAT and <em>DNase</em> I) in new-onset T1D patients <em>b</em>ut not in those with T2D. Of PAD4, NE, and PR3, PAD4 was found to <em>b</em>e the most sensitive <em>b</em>iomarker for the diagnosis of T1D. Furthermore, circulating levels of zonulin and LPS were not only increased, <em>b</em>ut were also strongly correlated with NET formation and ANCA generation in T1D patients.</A<em>b</em>stractText><A<em>b</em>stractText>This study provides evidence that increased formation of NETs, particularly PAD4, is closely associated with gut leakage in T1D <em>b</em>ut not T2D, and suggests that microorganisms and the release of neutrophil cytoplasmic <em>anti</em>gen during the formation of NETs may <em>b</em>e involved in the pathogenesis of T1D.</A<em>b</em>stractText>
Publication
Journal: American journal of diseases of children (1960)
November/15/1992
Abstract
OBJECTIVE
To determine whether cephalexin or penicillin is more effective in the treatment of group A beta-hemolytic streptococcal tonsillopharyngitis in children.
METHODS
Randomized, double-blind, crossover study conducted from 1981 to 1984.
METHODS
Seven pediatric practices in the United States, including private offices and pediatric clinics.
METHODS
Of the 654 patients, 525 children and adolescents with clinical evidence of tonsillitis or pharyngitis and throat cultures positive for group A beta-hemolytic streptococcal infection were evaluable. Eighty percent of patients completed the study; none were withdrawn because of adverse reaction.
METHODS
Children and adolescents who had acute illness suggestive of group A beta-hemolytic streptococcal infection were enrolled in the study. Treatment was continued if the throat culture was positive for group A beta-hemolytic streptococcal infection.
METHODS
Four doses of cephalexin and penicillin (27 mg/kg per day) were prescribed to be taken on an empty stomach for 10 days.
RESULTS
Symptomatic clinical failure occurred in 8% of penicillin-treated patients and in 3% of cephalexin-treated patients. Bacteriologic failure rates were 11% in the penicillin treatment group and 7% in the cephalexin treatment group. The combined treatment failure rate of clinical relapse plus asymptomatic bacteriologic failure was 19% in the penicillin treatment group and 10% in the cephalexin treatment group. Paired antistreptolysin-O titer increased significantly in 62.3% of penicillin-treated patients and in 64.2% of cephalexin-treated patients. Similarly, anti-DNase B titers rose 52.2% in penicillin-treated patients and 52.4% in cephalexin-treated patients.
CONCLUSIONS
Cephalexin is a more effective drug than penicillin in the treatment of group A beta-hemolytic streptococcal throat infection in children.
Publication
Journal: Journal of Immunology
November/13/2000
Abstract
TCR engagement of immature CD4(+)CD8(+) thymocytes induces clonal maturation (positive selection) as well as clonal deletion (negative selection) in the thymus. However, the cell death execution events of thymocytes during the negative selection process remain obscure. Using a cell-free system, we identified two different DNase activities in the cytosol of in vivo anti-TCR-stimulated murine thymocytes: one that induced chromosomal DNA fragmentation, which was inhibited by an inhibitor of caspase-activated DNase, and another that induced plasmid DNA degradation, which was not inhibited by an inhibitor of caspase-activated DNase. We purified the protein to homogeneity that induced plasmid DNA degradation from the cytosol of anti-CD3-stimulated thymocytes and found that it is identical with cyclophilin B (Cyp B), which was reported to locate in endoplasmic reticulum. Ab against Cyp B specifically inhibited the DNA degradation activity in the cytosol of anti-CD3-stimulated thymocytes. Furthermore, recombinant Cyp B induced DNA degradation of naked nuclei, but did not induce internucleosomal DNA fragmentation. Finally, we demonstrated that TCR engagement of a murine T cell line (EL4) with anti-CD3/CD28 resulted in the release of Cyp B from the microsome fraction to the cytosol/nuclear fraction. Our data strongly suggest that both active caspase-activated DNase and Cyp B may participate in the induction of chromosomal DNA degradation during cell death execution of TCR-stimulated thymocytes.
Publication
Journal: Deutsche Medizinische Wochenschrift
August/31/1976
Abstract
Sera from normal controls from patients with streptococcal diseases, and from other patients whose serum was sent for anti-streptolysin 0 determinations were tested for antistreptolysin 0 (ASO) and anti-DNase B (ADB) antibodies. The Streptozyme test was performed on the same sera. The upper limits of normal in the control population were established as 160 units for ASO and as 240 units for ADB, respectively. The usefulness of the ADB test in addition to the ASO test was confirmed: when both tests were performed elevated titers could be demonstrated in a higher percentage of various streptococcal diseases. With respect to streptococcal infections of the skin the anti-DNase B-test was superior to the ASO test. In this study of the Streptozyme test showed an elevated antibody titer in a lower proportion than the other two tests.
Publication
Journal: Pediatrics
June/27/1993
Abstract
OBJECTIVE
To determine if it is appropriate to recommend that patients with group A beta-hemolytic streptococcal pharyngitis, who are clinically well by the morning after starting antibiotic treatment, can return to school or day care, or if they should wait until they have completed 24 hours of antibiotics as recommended by the American Academy of Pediatrics Committee on Infectious Diseases.
METHODS
We examined the duration of positivity of the throat culture after antibiotics were begun as a means of assessing the potential risk of transmission to close school contacts. Forty-seven children (4 to 17 years of age) with pharyngitis and a positive throat culture for group A streptococci in an outpatient, staff model health maintenance organization clinic were enrolled and were randomly selected to receive therapy with either oral penicillin V, intramuscular benzathine penicillin G, or oral erythromycin estolate. Additional throat cultures were obtained and clinical findings were recorded for each child during three home visits in the 24 hours after their initial clinic visit. Acute and convalescent sera were obtained for determination of anti-streptolysin O and anti-DNase B titers.
RESULTS
Seventeen (36.2%) of the 47 patients had a positive culture the morning after initiating antibiotic therapy. However, thirty-nine (83%) of the patients became "culture negative" within the first 24 hours. Neither the time interval to the first negative culture nor the presence or absence of group A streptococcal organisms on any single convalescent culture could be predicted by clinical findings. Six of the eight children who failed to convert to a "negative" throat culture within 24 hours of initiating therapy were receiving erythromycin. We could detect no difference in either time to conversion to a negative culture or the presence of a positive culture 24 hours after starting antibiotics between those who demonstrated a significant antibody increase and those who did not.
CONCLUSIONS
The data from this study strongly suggest that children with group A beta-hemolytic streptococcal pharyngitis should complete a full 24 hours of antibiotics before returning to school or daycare.
Publication
Journal: Cell Biology International
March/9/1999
Abstract
Bovine zeta-crystallin has the ability to bind with different DNAs. Initially, this protein was named regulatory factor 36 (Kang et al., 1985), but it has been shown to be an ocular lens zeta-crystallin (Jörnvall et al., 1993), which is considered an enzyme-crystallin (Rodakanaki et al., 1989). The enzyme-linked immunosorbent assay (ELISA) was used to quantitate the binding of bovine zeta-crystallin to purified high molecular weight double-stranded (ds-) and single-stranded (ss-) DNA (bovine and synthetic DNA). ELISA quantitation was achieved by the addition of anti-zeta-crystallin antibodies to the DNA-zeta-crystallin complex, using a novel immunochemical avidin-biotin method. Zeta-crystallin shows much greater binding intensity for ss-DNA and for ds-Z-DNA than for ds-B-DNA. It also reacts slightly more with ds-Z-DNA than ss-DNA. Therefore, we speculate that zeta-crystallin may act as a transcriptional enhancer (outer lens cortex), possibly binding to Z-DNA regulatory elements within lens crystallin genes. It may also act to protect DNA from endogenous DNase activity and as a DNA unwinding (destabilizing) protein also involved with transcription, occurring in normal adult bovine lens nucleated secondary fiber cells.
Publication
Journal: Laboratory Investigation
May/23/1978
Abstract
Epithelioid liver cells were established in culture from rats sacrificed 10 to 18 weeks after the administration of the hepatocarcinogen diethylnitrosamine in their drinking water. After approximately 3 months in vitro, more than half the cells propagated from rats that developed hepatocellular carcinomas had bean-shaped, acentrically displaced nuclei with large juxtanuclear homogeneous appearing areas resembling the hyalin or Mallory bodies in the livers of chronic alcoholics. These abnormalities were not seen in the livers of origin, but were retained in the carcinomas that formed after the cultured cells containing such juxtanuclear hyalin inclusions were inoculated into young rats or nude (i.e., thymusless) mice; these features persisted upon reestablishment and continuous passage of the tumor cells in culture. The cells were further characterized by their karyotypes and their growth properties in liquid media and soft agar. By transmission electron microscopy the hyaline bodies in the culture tumor cells were shown to consist of a disorganized meshwork of filaments. Examination by incubating cells with cytochalasin B and by using antiactin and anti-DNase antisera as indirect immunofluorescence probes also revealed a disturbance in the cytoskeleton.
Publication
Journal: Molecular and Cellular Biochemistry
December/26/2002
Abstract
In various peroxynitrite (PN)-treated proteins, the formations of stable 3-nitrotyrosine (nitration) and labile S-nitrosocysteine (S-nitrosation) were observed by employing rapid Western blot in 6 h. The steps of SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and membrane-blotting were performed at 4 degrees C. It was noted that the intensity of immunoreactive bands specific for anti-nitrotyrosine was stronger than that specific for anti-S-nitrosocysteine. Additionally, the intensity was in the manner of a dose-dependency of PN. Nitration/S-nitrosation were formed in the following treated proteins, including bovine serum albumin (BSA), DNase-1, ceruloplasmin, catalase and hemoglobin (Hb). The incubation of PN-pretreated hemoglobin with 1 mM reduced glutathione (GSH) did not change immunoreactivity significantly. However, the addition of glutathione S-transferase (GST) or glutathione peroxidase (GPX) to the above incubation mixture, resulted in decreased immunoreactivity, suggesting GSH may form a transition complex with PN-pretreated hemoglobin and/or partially reduce/modify the treated hemoglobin, thereby increasing the accessibility for the subsequent modification by GST or GPX. Such decreased immunoreactivity indicates that nitrotyrosine and S-nitrosocysteine of treated hemoglobin was, indeed, further modified via (a) converting -NO2 to -NH2 in tyrosine residues, (b) denitrating -NO2 directly/indirectly in tyrosine residues, and/or (c) changing -S-NO to -SH in cysteine residues, or denitrosation. The findings imply similar enzymatic modifications of proteins may also occur in vivo, and therefore play a pivotal role in the NO-related cellular signaling cascade(s).
Publication
Journal: American Journal of Nephrology
October/15/1984
Abstract
The prevalence of circulating immune complexes (CIC) was investigated using the C1q binding assay (C1q BA) and the conglutinin binding assay (Kg BA) in 200 patients undergoing maintenance hemodialysis. Increased C1q binding was found in 45% (87 of 194) of the patients, and the modified Kg BA gave elevated values in 31% (20 of 65). The prevalence of CIC was similar in American and Swiss patients, and in patients undergoing hemodialysis, self-dialysis or peritoneal dialysis. In patients with 'nonimmunological' renal diseases, CIC were detected with similar frequency. No change in CIC was noted during hemodialysis in 6 additional patients tested. The abnormality was not related to age, sex, duration of dialysis, hepatitis B antigenemia, bacterial infections, or transfusions. Anti-DNA antibodies were absent in all subjects tested and the results of the C1q BA were not changed by DNase digestion of eight sera with high C1q binding. Rheumatoid factor activity (RF) was detected in approximately one-fifth of the patients, and there was a direct correlation between positive C1q binding and RF. There was no correlation between CIC and lymphocytotoxic antibodies. This study demonstrated a high prevalence of CIC in dialyzed uremic patients and established its relationship to other immunological abnormalities.
Publication
Journal: Molecular Therapy - Methods and Clinical Development
November/13/2018
Abstract
Autologous transplantation of hematopoietic stem cells transduced with a lentiviral vector (LV) expressing an anti-sickling HBB variant is a potential treatment for sickle cell disease (SCD). With a clinical trial as our ultimate goal, we generated LV constructs containing an anti-sickling HBB transgene (HBBAS3), a minimal HBB promoter, and different combinations of DNase I hypersensitive sites (HSs) from the locus control region (LCR). Hematopoietic stem progenitor cells (HSPCs) from SCD patients were transduced with LVs containing either HS2 and HS3 (β-AS3) or HS2, HS3, and HS4 (β-AS3 HS4). The inclusion of the HS4 element drastically reduced vector titer and infectivity in HSPCs, with negligible improvement of transgene expression. Conversely, the LV containing only HS2 and HS3 was able to efficiently transduce SCD bone marrow and Plerixafor-mobilized HSPCs, with anti-sickling HBB representing up to ∼60% of the total HBB-like chains. The expression of the anti-sickling HBB and the reduced incorporation of the βS-chain in hemoglobin tetramers allowed up to 50% reduction in the frequency of RBC sickling under hypoxic conditions. Together, these results demonstrate the ability of a high-titer LV to express elevated levels of a potent anti-sickling HBB transgene ameliorating the SCD cell phenotype.
Publication
Journal: Microbial Pathogenesis
August/20/2018
Abstract
In the last few years, the demand for the tremendous therapeutic applications of indigenous probiotic bacteria from diversified fermented food products has surged. In view of this, the present study was documented to evaluate the anti-tubercular and probiotic properties of coagulase-negative staphylococci (CNS) indigenous to Koozh, a traditional fermented food product of South India. A total of 18 isolates were purified from Koozh, and tested for anti-tubercular activity against Mycobacterium tuberculosis H37Rv using luciferase reporter phage (LRP) assay. Among them, six isolates revealed higher percentage (>90%) of relative light unit (RLU) reduction. These six isolates were further evaluated for their in vitro probiotic attributes using standard protocols. All six staphylococci strains disclosed good probiotic properties. Moreover, Staphylococcus hominis strain MANF2 showed high cell survival percentage (92.2%) at pH 2.0 as well as towards simulated gastric juice (88.51%). Furthermore, strain MANF2 was found to be resistant to bile salt after 24 h of incubation with maximal viability of 5.71 ± 0.02 log cfu/mL, and depicted the deconjugation of bile salt as well. All the isolates exhibited strong auto-aggregation capacity (44.4 ± 1.2-68.1 ± 1.5%), and hydrophobicity against toluene (55.0 ± 1.2-72.0 ± 1.1%). Additionally, strain MANF2 was observed to be highly resistant to phenol (6.27 ± 0.01 log cfu/mL) and lysozyme (81.1 ± 1.6% viability). Most importantly, all six isolates depicted good hypocholesterolemic effect, slight β-galactosidase activity, and moderate proteolytic property. The strains were sensitive to all the tested conventional antibiotics, except Nalidixic acid. In addition to this, all staphylococci strains demonstrated significant DPPH (2,2-Diphenyl-1-picrylhydrazyl) scavenging, hydrogen peroxide tolerance, and hydroxyl radical scavenging activity in a dose dependent manner, thereby exhibiting the potent antioxidative properties of isolates. The negative results obtained from haemolytic, DNase, and gelatinase tests revealed the non-pathogenicity and safety aspect of these strains. In a nutshell, the present investigation divulges the persuasive anti-tubercular and probiotic properties of staphylococci, particularly strain MANF2, and recommended the further exploitation of Koozh associated CNS in pharmaceutics.
Publication
Journal: Japanese journal of cancer research : Gann
September/28/1994
Abstract
We analyzed the biochemical nature of beta m-actin protein found in mouse B16 melanoma. When we carried out immunostaining with the antibody specific to beta m-actin, filamentous immunofluorescence was observed in B16-F1, a low-metastatic cell line expressing beta m-actin, but not in highly metastatic B16-F10 that did not express beta m-actin. When a purified actin fraction containing beta m-actin was polymerized and immunoprecipitated with anti-beta m-actin antibody, the immunoprecipitate contained beta m-, beta- and gamma-actin. This indicated that the beta m-actin was incorporated into an actin filament together with beta- and gamma-actin in vitro, and this phenomenon was consistently suggested by cellular double immunostaining with anti-beta m-actin and common anti-actin antibody. When the actin fraction containing beta m-actin under a regular depolymerizing condition was subjected to immuno-adsorption assay using anti-beta m antibody and protein-A Sepharose, the immunoadsorbed aggregates contained beta m-, beta- and gamma-actin. This indicates that the actin fraction was not completely depolymerized and contained beta m-actin-containing oligomers, which were too small to be precipitated with anti-beta m-actin antibody alone. The incomplete depolymerization of the beta m-actin-containing fraction was also suggested by the much lower DNase 1 inhibition activity of the beta m-actin-containing fraction than that of beta- and gamma-actin fraction. Furthermore, a DNase 1 binding assay showed that cytoplasmic supernatant prepared from B16-F1 under a low-ionic condition contained less monomeric actin than the cytoplasmic preparation from B16-F10. These results suggested that beta m-actin protein in B16 melanoma probably inhibits the dynamic conversion between the monomeric and polymerized forms of actin, leading to a decrease in cell motility and consequently the suppression of invasiveness and metastasis.
Publication
Journal: Current Cancer Drug Targets
May/18/2011
Abstract
Pokemon gene has crucial but versatile functions in cell differentiation, proliferation and tumorigenesis. It is a master regulator of the ARF-HDM2-p53 and Rb-E2F pathways. The facts that the expression of Pokemon is essential for tumor formation and many kinds of tumors over-express the Pokemon gene make it an attractive target for therapeutic intervention for cancer treatment. In this study, we used an RNAi strategy to silence the Pokemon gene in a cervical cancer model. To address the issues involving tumor specific delivery and durable expression of siRNA, we applied the Arg-Gly-Asp (RGD) peptide ligand and polylysine (K(18)) fusion peptide to encapsulate a recombinant retrovirus plasmid expressing a siRNA targeting the Pokemon gene and produced the 'mimoretrovirus'. At charge ratio 2.0 of fusion peptide/plasmid, the mimoretrovirus formed stable and homogenous nanoparticles, and provided complete DNase I protection and complete gel retardation. This nanoparticle inhibited SiHa cell proliferation and invasion, while it promoted SiHa cell apoptosis. The binding of the nanoparticle to SiHa cells was mediated via the RGD-integrin α(v)β(3) interaction, as evidenced by the finding that unconjugated RGD peptide inhibited this binding significantly. This tumor-targeting mimoretrovirus exhibited excellent anti-tumor capacity in vivo in a nude mouse model. Moreover, the mimoretrovirus inhibited tumor growth with a much higher efficiency than recombinant retrovirus expressing siRNA or the K(18)/P4 nanoparticle lacking the RGD peptide. Results suggest that the RNAi/RGD-based mimoretrovirus developed in this study represents a novel anti-tumor strategy that may be applicable to most research involving cancer therapy and, thus, has promising potential as a cervical cancer treatment.
Publication
Journal: Clinical Pediatrics
April/15/2009
Abstract
The duration of treatment and appropriate guidelines for antibiotic prophylaxis for children with poststreptococcal reactive arthritis (PSRA) have not been determined. The authors performed a retrospective chart review of 40 children with PSRA and examined their clinical features at initial evaluation and at 6, 12, and 24 months. At baseline, 18% (n = 7) had a finding noted on the echocardiogram. Although most patients developed cardiac findings early on in the course of their disease, 2 patients with a normal baseline echocardiogram may have developed findings after 12 months of follow-up. The mean duration of prophylaxis was 22 months. During the follow-up period, there was improvement in Physician's Global Assessment, number of patients with arthralgia, tender and swollen joints, erythrocyte sedimentation rate, anti-streptolysin O, and anti-DNAse B antibody titers. The authors conclude that marked improvement in clinical features and laboratory values was seen over time. Patients may benefit with long-term cardiac follow-up.
Publication
Journal: Acta Oto-Laryngologica
December/9/1987
Abstract
In 82 patients with acute tonsillitis studied, beta-hemolytic group A streptococci were isolated from 30 (37%), and group C or G streptococci from 12 (15%). In the 40 patients with non-streptococcal tonsillitis there was a significantly higher isolation rate of pneumococci, H. influenzae and/or B. catarrhalis, as compared with those with beta-hemolytic streptococci. Patients were classified regarding clinical status according to standardized criteria as severe, moderate, or mild. The patients with group A streptococcal tonsillitis were significantly more often classified clinically as 'severe' and had significantly shorter duration of symptoms before seeking medical care, as compared with those with non-streptococcal tonsillitis. Significant increases in white blood cell count and in anti-DNase B were found in the patients with group A streptococcal tonsillitis, whereas their antistreptolysin O levels did not increase significantly. C-reactive protein concentrations were consistently higher in the patients with group A streptococcal tonsillitis. No evidence of polyclonal beta-lymphocyte stimulation was found when measuring antibodies against pneumococci and group B streptococci. The findings show clinical and simple laboratory tests to be useful aids in distinguishing group A streptococcal tonsillitis from non-streptococcal tonsillitis, and that other bacteria may be involved in non-streptococcal tonsillitis.
Publication
Journal: The Journal of laboratory and clinical medicine
November/7/1975
Abstract
The dynamics of the immune response to streptococcal extracellular antigens as measured by the streptozyme agglutination test have been defined in experimental animals andcompared with the dynamics of the immune response as determined by three established neutralization tests for streptococcal antibodies (ASO, anti-DNase B,and anti-NADase). In rabbits immunized with streptococcal extracellular Streptozyme-measured antibodies rose more quickly and peaked earlier than did antibodies to streptolysin O, streptococcal DNase-B, and streptococcal NADase. Additional studiesrevealed that the early peak was primarily due to 2-mercaptoethanol-sensitive (19S) antibody and that the later rise in Streptozyme-measured antibodies was due to 2-mercaptoethanol-resistant (7S) antibody. Preliminary observations using sucrose gradient ultracentrifugation tended to confirm this interpretation. These data provide a possible explanation for the early detection of a streptococcal antibody response by the Streptozyme test which has also been described in humans. The data suggest a theoretical advantage for the Streptozyme agglutination test in patients with streptococcal infections and their sequealae. However, the complexity of the Streptozyme reagent suggests that more extensive studies are needed to assure the consistent reproductivity of results with different lots of the test reagent.
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