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T Koga

Publications and source records attributed to T Koga.

At least 469 records · Page 26Linked to original sources
PubMed1990

[Pharmacokinetics and clinical effects of cefdinir 5% fine granules in pediatrics].

Cefdinir (CFDN), a newly developed oral cephalosporin in 5% fine granular form, was administered to 10 boys at 1 hour before meal (in the fasting state) and concentrations of the drug in plasma and urine and its urinary recovery rates were determined. The subjects were divided into 2 groups of 5 boys each; one group received 3 mg/kg of CFDN, and the other, 6 mg/kg. To 6 of the 10 children the drug was administered in the two different dose levels using the cross-over method. To study clinical and bacteriological effects of this drug, a mean dose of 4.6 mg/kg t.i.d. was administered for 8 days on the average to 40 children with various infections; pharyngitis (4 cases), tonsillitis (2), acute bronchitis (2), pneumonia (8), scarlet fever (6), acute purulent otitis media (1), urinary tract infection (12), impetigo (2), phlegmon (1), lymphadenitis (1) and subcutaneous abscess (1). MICs were determined for 6 drugs including CFDN, cefaclor, cefixime (CFIX), methicillin, cloxacillin (MCIPC), amoxicillin (AMPC) against 13 strains of 6 species freshly isolated from children receiving CFDN. An inoculum size of 10(6) cfu/ml was used in the MIC-determinations. Adverse reactions and abnormal laboratory findings attributable to this drug were also examined in these patients. The results obtained are summarized as follows. 1. Mean plasma peak levels of CFDN were observed at 3 hours after administration in both the 3 mg/kg and 6 mg/kg groups with mean peak values of 0.68 and 1.35 micrograms/ml, respectively. Mean half-lives were 2.06 hours in the 3 mg/kg group and 1.61 hours in the 6 mg/kg group, and mean AUCs were 3.5 in the former and 6.5 micrograms.hr/ml in the latter. Thus, dose-response between the 2 doses was observed in plasma levels and AUCs. 2. To 3 patients, CFDN was given in the two different doses using the cross-over method. Mean plasma peak levels of CFDN were 0.71 and 1.31 micrograms/ml in the doses of 3 mg/kg and 6 mg/kg, respectively. Half-lives were 1.39-2.90 hours in the 3 mg/kg group and 1.21-1.48 hours in the 6 mg/kg group, with AUCs of 3.4-3.7 and 4.1-7.5 micrograms.hr/ml, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗
PubMed1990

[Isolation of a strain of M. tuberculosis which is considered to be rifampicin-dependent, from a patient with long-lasted smear positive and culture difficult (SPCD) mycobacteria].

During the course of clinical examination of drug sensitivity tests for M. tuberculosis, a strain of M. tuberculosis which is considered to be rifampicin-dependent was isolated from a patient with persisting smear positive, culture negative (SPCN) or culture difficult (SPCD) mycobacteria status. The strain isolated produced a few tiny colonies on the control Ogawa-egg yolk medium, whereas it showed abundant growth like a bacteria plaque on the medium containing rifampicin 50 micrograms/ml. Furthermore, the growth of the strain on Ogawa medium containing rifampicin 50 micrograms/ml is much better than that on the medium containing rifampicin 10 micrograms/ml.

Colony Count, Microbial↗
PubMed1990

Monosialoganglioside effects following cerebral ischemia: relationship with anti-neuronotoxic and pro-neuronotrophic effects.

Increasing evidence is available indicating that systemically administered GM1 is able to provide for functional recovery in different experimental models of CNS injury, including cerebral ischemia. Current evidence indicates that the GM1 effects are associated, in the acute phase, with attenuation of secondary neuronal damage due to its capability to antagonize excitatory amino acid-related neurotoxicity in vivo as in vitro. Furthermore, the ganglioside is able to facilitate occurrence of long-term reparative processes, an effect most likely reflecting the potentiation of the action of neuronotrophic factors. This bifaceted action of GM1 makes the ganglioside ideally suited for clinical treatment of patients afflicted by cerebrovascular insufficiencies.

Animals↗
PubMed1990

[Evaluation of effectiveness of rokitamycin dry syrup in acute enteritis in pediatrics. A comparative study on rokitamycin and fosfomycin dry syrups].

Because Campylobacter jejuni is most frequently identified as a causative organism of bacterial enteritis in pediatrics, a study was done to evaluate the clinical efficacy against Campylobacter enteritis and the safety of a macrolide antibiotic, rokitamycin (RKM). In case of acute enteritis, RKM was used in a form of dry syrup at a dose level of approximately 30 mg (in potency)/kg body weight and its efficacy and safety were compared to those of fosfomycin (FOM) dry syrup which is currently in use at a dose level of 60 mg (in potency)/kg. Both drugs were administered, as a rule, in 3 divided daily dose (RKM before meal and FOM after meal) for 5 consecutive days. Comparisons of the drugs were made using a well-controlled method. Obtained results are summarized as follows. 1. No significant differences in background factors of the 2 drug groups were apparent, hence it was deemed that no obstacles existed in making comparative studies of the 2 groups with regard to their efficacies and safeties. 2. Overall efficacy rate against Campylobacter enteritis was 100% in the RKM group with a rate of excellent efficacy of 91.3% and the former was 94.4% in the FOM group with the latter of 72.2%. Though the RKM group apparently showed higher rates by 5.6% and 19.1%, respectively, for overall and excellent efficacies, they were not statistically significant as both drugs showed good efficacies. When acute cases of enteritis other than those caused by Campylobacter were included in the analysis, overall efficacy rates and rates of excellent efficacy were, respectively, 97.6% and 85.7% for the RKM group and 88.6% and 68.2% for the FOM group, thus RKM showed higher efficacy rates by 9.0% and 17.5%, respectively. These differences were deemed statistically significant using the U-test. 3. Numbers of days required for most of the major symptoms to subside were 3 days or less for the group for which RKM was used against Campylobacter enteritis. Similar results were observed for the FOM group also. In cases of acute enteritis due to other causes than Campylobacter, slower recoveries were observed for both the RKM and the FOM groups than in Campylobacter enteritis cases, with the latter group slower than the former. In cases of puruloid stool, the recovery in the RKM group was significantly faster by U-test than the FOM group, and a similar trend was observed overall. 4. Bacteriologically, the eradication rate of Campylobacter in the RKM group was very good at 91.3% with the FOM group showing a rate of 78.9%.(ABSTRACT TRUNCATED AT 400 WORDS)

Acute Disease↗
PubMed1990

[Experimental and clinical studies on cefodizime in pediatrics].

Cefodizime (CDZM), a newly developed injectable cephem antibiotic, was given via bolus intravenous injection at each of 3 dose levels of 10, 20 and 40 mg/kg to each 3 children, and serum and urinary levels and urinary recovery rates were followed. A total of 57 patients received CDZM in the following regimen via bolus intravenous injection, and clinical efficacies, and microbial responses were evaluated. Mean dosage per application: 20.9 mg/kg, number of application per day: between 2 and 4 (2 times for 3 patients, 3 for 26 patients and 4 for 28 patients), mean duration of the therapy: 1 week. Patients consisted of 1 case of peritonsillar abscess, 2 acute bronchitis, 38 pneumonia, 8 urinary tract infection, 1 staphylococcal scalded skin syndrome, 2 cellulitis, 4 purulent lymphadenitis and 1 typhoid fever. In addition to the patients mentioned above 6 patients who dropped out were involved in the evaluation of adverse reactions and influence of the drug on laboratory test data, and the following results were obtained. 1. Five minutes after bolus intravenous injection in doses of 10, 20 and 40 mg/kg, serum levels determined by the bioassay method were at their maxima, i.e. 114.0, 264.6 and 461.6 micrograms/ml, respectively. Serum levels of drugs were dose-dependent throughout all the dosage levels tested. Mean serum half-lives of the drug were 1.757, 1.552 and 1.668 hours, respectively, for the 3 dose levels. Serum levels of the drug determined by the HPLC method were similar to those by the bioassay method: The maximum serum levels occurred at 5 minutes after administration, mean maximum concentrations were 105.5, 264.0 and 461.7 micrograms/ml for the 3 dose levels, and a dose response was noted for the 3 dose levels. The half-lives were 1.755, 1.598 and 1.668 hours, respectively. 2. Mean maximum concentrations in urine determined by bioassay for 2 of 3 cases received 10 mg/kg and 3 cases each given 20 and 40 mg/kg of CDZM were 884.3, 3,061 and 7,352 micrograms/ml, respectively, in the first 2 hours after administration. These levels were also dose-dependent. Mean recovery rates were 74.4, 78.4 and 71.5%, respectively, in the first 8 hours after administration. Mean maximum concentrations in urine measured by HPLC were similar to those determined by bioassay, i.e. 962.3, 3,404 and 7,899 micrograms/ml in the first 2 hours. They were, also, dose-dependent. Mean recovery rates were 82.1, 86.0 and 76.5%, respectively, in the first 8 hours after administration. The HPLC determinations gave slightly higher levels than the bioassay.(ABSTRACT TRUNCATED AT 400 WORDS)

Age Factors↗
PubMed1990

[Pharmacokinetics and clinical studies of norfloxacin in the pediatric field].

Norfloxacin (NFLX) tablets with a potency of 50 mg/tablet or 100 mg/tablet were administered at doses of 1 to 4 tablets (1.5 to 6.1 mg/kg) orally 30 minutes before meals to 12 children with ages ranging from 8 years 9 months to 12 years 5 months, and serum/urinary NFLX levels and urinary recovery rates were determined. The drug sensitivity tests for NFLX and 10 other drugs were conducted against 128 strains of Shigella sonnei (10(6) CFU/ml) which had been isolated from pediatric patients with bacillary dysentery. In order to evaluate clinical and bacteriological effects of NFLX and its safety in the pediatric field, NFLX 50 mg tablets were administered t.i.d. (mean 8.3 mg/kg) for 5 days to 42 pediatric patients with bacillary dysentery. Similarly, this drug was administered in b.i.d. or t.i.d. (mean 6.7 mg/kg) for 4 days to 4 pediatric patients with urinary tract infections. The following results were obtained: 1. According to the dosage, the subjects were divided into 3 groups with dose levels 1.5-2.8 mg/kg, 3.1-4.7 mg/kg and 5.2-6.1 mg/kg. These groups had 5, 2 and 5 subjects, respectively. Mean serum drug concentrations for the 3 dosage groups were at peak levels of 0.27, 0.64 and 1.51 micrograms/ml at 4, 2 and 1 hour(s) after administration, respectively. Pharmacokinetic parameters for these dosage groups were as follows: Tmax values were 3.0, 3.0 and 1.2 hours; Cmax values were 0.32, 0.78 and 1.56 micrograms/ml; serum half-lives were 2.2, 2.4 and 2.3 hours; and AUCs were 1.65, 3.98 and 6.06 micrograms.hr/ml, respectively. Thus, dose-dependent responses were observed among the 3 dosage groups. 2. Mean peak urinary drug concentrations for the 3 dosage groups were 45.8, 109.2 and 215.1 micrograms/ml, respectively, and the peaks appeared 2-4 hours after administration. Mean recovery rates up to 8 hours after administration were 18.3%, 24.5% and 28.7%, respectively for the 3 dosages. 3. In a drug sensitivity test against 128 strains of S. sonnei, the most frequent MIC value of NFLX was 0.78 micrograms/ml against 65 strains, followed by 0.39 micrograms/ml for 56 strains. Together, these strains accounted for 94.5% of the strains tested. No resistant strain to this drug was observed and the antibacterial activity of this drug was second only to colistin, similar to that of ofloxacin, better than those of enoxacin and seven other drugs. 4. Clinical efficacy rate of NFLX against bacillary dysentery was 95.2% in 21 cases in which the evaluation was possible.(ABSTRACT TRUNCATED AT 400 WORDS)

Age Factors↗
PubMed1990

[Influence of cefodizime via intravenous bolus injection on human fecal flora].

Cefodizime (CDZM), a newly developed injectable cephem antibiotic, was given to 8 healthy male volunteers with ages 23-28 years (mean: 24 years) and body weights 54-73 kg (mean: 64 kg). 4 volunteers received 2 g b.i.d., intravenous infusion for 5 days, and 4 volunteers had 4 g b.i.d. for the same duration. We studied changes in bacterial flora and drug levels in feces, as well as changes in susceptibility of isolated microbes to CDZM, cefmetazole, cefotaxime (CTX) and cefoperazone. Adverse drug reactions and changes in laboratory findings were also investigated. The following results were obtained. 1. In fecal flora for the 2 g b.i.d. group, on day 3 of treatment Enterobacteriaceae were identified in only 2 of the 4 cases. Individual microbe counts decreased or fell below detection limit (10(2) cells/g) on day 3 of treatment. Colony forming units (CFUs) of Enterobacteriaceae on day 5 of treatment were similar to those on day 3. After the end of treatment, its CFUs increased. The mean CFU of Enterobacteriaceae on day 10 after the end of treatment increased to about the same level as before dosing. However, some microbes did not revert to pretreatment levels. Of other Gram-negative bacilli, Pseudomonas sp. increased in one case transiently on day 3 of treatment. After day 3 of treatment, its CFU decreased. Gram-positive microbes showed various changes. Mean CFU of yeast like organism (YLO) increased between day 3 of treatment and day 3 after the end of treatment and its mean CFU decreased on day 10 after the treatment. As for anaerobes, CFUs of Bacteroides fragilis group organisms and overall anaerobes showed no distinctive changes. Clostridium difficile were detected in two cases. In one case, C. difficile was noted at levels between 1.1 X 10(3) cells/g and 2.0 X 10(6) cells/g at the following sampling times: days 1 and 3 of treatment and days 3, 5, 10 and 20 after the end of treatment. In other case, it was noted at levels of 1.8 X 10(5) cells/g on day 20 after the end of treatment. D-1 toxin was detected in one case before dosing, and in three cases (the concentration of D-1 toxin was 250 ng/g or 500 ng/g) on day after treatment. Enterobacteriaceae in fecal flora of 4 cases given 4 g b.i.d. frequently decreased or fell below detection limit on days 3 and 5 of treatment and day 3 after the end of treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1990

Hypoxic-ischemic damage and the neuroprotective effects of GM1 ganglioside.

In vitro studies have shown that monosialoganglioside GM1 reduces excitatory amino acid-related neurotoxicity by limiting the downstream consequences of abusive excitatory amino acid receptor stimulation. Systemic administration of GM1 appears to be efficacious in reducing acute neuronal damage and in facilitating medium- and long-term functional recovery after brain injury. We propose that GM1 protective effects in the acute injury phase results from attenuation of excitotoxicity, whereas the functional recovery seen at longer term could reflect GM1 potentiation of neuronotrophic factors. The potential therapeutic efficacy of GM1 administration in humans is suggested by clinical studies demonstrating improved neurologic outcome in stroke patients.

Amino Acids↗
PubMed1990

[Three patients with typical sandblaster's silicosis proven by mineralogical analysis].

Three family members who had worked as sandblasters in their own sandblasting factory showed innumerable small nodularities in both lung fields of their chest radiograms. One of those showed conglomerate shadows in the upper lung fields. Those shadows seemed to be consistent with those of silicosis. One of the patients was examined by transbronchial lung biopsy (TBLB) and showed typical silicotic nodules. Mineralogical studies were done on the abrasive particles and the deposited particles in the lung tissue specimen obtained via TBLB and bronchoalveolar lavage fluid sample (BALF) using polarized microscopy, X-ray diffraction and analytical electron microscopy. The particles which had accumulated on the floor of the factory mineralogically consisted of mostly (over 90%) silica quartz containing small amount of chlorite, and the deposited particles in the lung tissue and those in the BALF showed similar composition.

Adult↗
PubMed1990

[Laboratory tests on cancer--cytology].

A comparative study was performed on needle aspiration cytology and the histological grading of 34 cases of small liver cancers. According to the Edmondson-Steiner's classification, 9 of the 34 cases were Grade I, 10 cases were a mixture of Grades I and II and 15 were Grade II or a mixture of Grades II and III or Grades I, II and III. The group consisting of Grade II and mixtures of Grades II and III or Grades I, Ii and III were diagnosed by needle aspiration cytology using cytological criteria described previously, but cases consisting of Grade I and mixtures of Grades I and II were very difficult to diagnose because of the relative lack of cellular atypia, and the diagnostic accuracy in this group was low. Retrospectively, ceLlularity, cellular architecture and the nuclear-cytoplasmic ratio were the most valuable cytological findings in the cases of Edmondson-Steiner's Grade I and the mixture of Grades I and II. In addition, some cases of small liver cancers had characteristically large lipid vacuoles which resembled a signet ring cell. Imprint cytology of neuroblastomas is a rapid diagnostic test which is very useful for differential diagnosis of neuroblastoma from other childhood solid tumors. Recently, flow cytometric DNA analysis and the N-myc oncogene have been proposed as important factors in the estimation of the prognosis of neuroblastomas. Three of fore patients with aneuploid DNA under the age of 1.5 years at diagnosis survive, while five of eight patients with diploid DNA over the age of 1.5 years at diagnosis died during a 12 to 120 month follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[Effect of rokitamycin on bacterial flora in human feces].

Rokitamycin, a newly developed macrolide antibiotic was orally administered to 7 healthy male volunteers (22-25 years) for 7 consecutive days to study changes in bacterial flora and concentrations of the drug in feces, and to observe adverse reactions and laboratory test parameters. A dose of 200 mg (2 tablets: 100 mg/tablet) was given 3 times daily before meals and the fecal studies were done on the 5 days before administration (adm.) [b.a.], at the time of administration (0), and the 3rd, 5th, 7th (the final day of treatment) days during adm. [u.a.] and the 3rd, 5th, 10th, 20th, 30th days after adm. [a.a.]. The results obtained are summarized as follows. 1. Obvious changes in mean populations of total aerobes and enterobacteriaceae were not found. In changes of each bacteria of enterobacteriaceae, Escherichia coli was not observed in cases from initial day of treatment to the 3rd day a.a. Cases from which Citrobacter sp. was isolated tended to increase after 3 days u.a. and gradually decrease after 3 days a.a. Among Gram-negative bacilli, cases where isolation of Pseudomonas sp. was observed increased temporarily on the 3rd u.a., Gram-positive cocci did not show particular patterns of changes. No changes in mean count of total anaerobes were observed during the course of the experiment. Among individual anaerobes, numbers of Lactobacillus and Peptococcaceae decreased slightly from the 3rd day u.a. and returned on the 5th day a.a. 2. Clostridium difficile D-1 toxin was detected in feces at amounts approximately 500 ng/g in 2 cases each on 20th and 30th day a.a., with 1 incidence occurring in the same person on the 2 separate days. 3. The drug was detected in all 7 cases on the 3rd, 5th and 7th days u.a., and in 1 cases each on the 5th and the 30th day a.a. The mean peak level was 315.5 micrograms/g on the 7th day u.a. The reason for the detection of the drug in feces in 1 case on the 30th day a.a. at a value of 5.90 micrograms/g was not clear. 4. Adverse reactions and abnormal laboratory test results due to this drug were not observed in any cases.

Administration, Oral↗
PubMed1990

[Pharmacokinetic and clinical evaluations of aztreonam monotherapy and aztreonam and ampicillin combination therapy in neonates and premature infants].

One-shot intravenous injection of aztreonam (AZT), a monobactam-class beta-lactam antibiotic, 20 mg/kg was administered to 4 neonates and 2 premature infants, a total of 6 cases, and plasma and urinary concentrations and urinary recovery rates were determined. Also, one-shot intravenous injection averaging 70.9 mg/kg/day of AZT alone was given to 0- to 43-day neonates and premature infants in b.i.d. to q.i.d. for an average of 8 days for the treatment (6 cases) and prophylaxis (11 cases) of infections. Furthermore, a combination therapy of AZT and ampicillin (ABPC) was applied to 0- to 79-day neonates and premature infants for the treatment (28 cases) and prophylaxis (18 cases) of infections. Average daily dosage of AZT 46.6 mg/kg was given by one-shot intravenous injection or by drip infusion in b.i.d. or t.i.d. for an average of 8 days. Average daily dosage of ABPC 78.6 mg/kg was given in the same daily frequency, route and average duration as AZT. Thus, clinical effects, prophylactic effects against infection, bacteriological effects as well as side effects and clinical laboratory test values were studied with the following results. 1. When AZT 20 mg/kg was administered to 1 case each of 6- and 7-day neonates by one-shot intravenous injection, the plasma concentrations were the highest at 5 minutes after the administration in both cases. Specifically, they were 62.9 and 72.7 micrograms/ml with AUCs of 216.6 and 231.6 micrograms.hr/ml and half-lives of 2.80 and 2.97 hours, respectively. When AZT 20 mg/kg was administered to 5- and 6-day premature infants by one-shot intravenous injection, the plasma concentrations were the highest at 15 minutes after administration in the former and 5 minutes in the latter, at values of 59.8 and 67.7 micrograms/ml, respectively. AUCs were 356.6 and 363.2 micrograms.hr/ml, respectively, and larger than AUCs of the above-mentioned neonates. Half-lives were 5.74 and 4.87 hours, respectively and longer than those of the above-mentioned neonates. When AZT 20 mg/kg was administered to 8- and 13-day neonates by one-shot intravenous injection, the plasma concentrations were the highest at 30 minutes after administration in the former and 5 minutes in the latter, at values of 43.4 and 76.9 micrograms/ml, respectively. AUCs were 202.9 and 189.8 micrograms.hr/ml, and 76.9 micrograms/ml, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Ampicillin↗
PubMed1989

Synthetic inositol trisphosphate analogs and their effects on phosphatase, kinase, and the release of Ca2+.

A series of inositol 1,4,5-trisphosphate (IP3) analogs and positional isomers was examined to explore the structure-activity relationships among IP3 5-phosphatase, IP3 3-kinase, and the release of Ca2+. All analogs with additional groups on the 2nd position of IP3 inhibited the hydrolysis of [5-32P]IP3 catalyzed by erythrocyte ghosts, with a lower Ki value than seen with IP3. IP3 dehydroxylated at the 2nd position also had a lower Ki, while 2,4,5-IP3 or cyclic(1:2), 4,5-IP3 had higher Ki values. Among these compounds 2-deoxy-IP3 was as potent as IP3 in inhibiting the phosphorylation by [3H] IP3-3-kinase in rat brain cytosol. The other compounds, except for 2,4,5-IP3 inhibited the phosphorylation, however, 2-30 times higher concentrations were required. By lowering free Ca2+, the concentrations required for half-maximal inhibition were low, while those of IP3, 2-deoxy-IP3, and positional isomers remained unchanged. These compounds acted as full agonists in releasing Ca2+ from permeabilized macrophages, although 1.6-50-fold higher concentrations than IP3 were required. These compounds also inhibited the binding of [3H]IP3 to rat cerebellum and bovine adrenal cortex microsomes, but the potencies were 2.9-33 times less than that of IP3. Thus, the 2nd position of IP3 can be modified with only a slight loss of biological activity.

Animals↗
PubMed1989

Membrane IL-1 induces bone resorption in organ culture.

We have studied the role of the membrane-associated form of IL-1 on bone resorption in vitro. Murine macrophages of the P388D1 cell line stimulated with LPS, subsequently fixed with paraformaldehyde, induced the proliferation of C3H/HeJ mouse thymocytes in the presence of a submitogenic concentration of Con A. Membrane IL-1 on P388D1 cells stimulated with LPS induced bone resorption in organ cultures of neonatal BALB/c mouse calvaria. Polyclonal antibodies directed against membrane IL-1 and soluble IL-1 from P388D1, and monospecific rabbit anti-murine rIL-1 alpha serum neutralized the membrane IL-1 activity, as measured by the thymocyte proliferation. In addition, these antibodies suppressed the bone resorption induced by membrane IL-1. The bone resorption induced by membrane IL-1 required direct contact between mouse calvaria and membrane IL-1. Salmon calcitonin strongly suppressed the calcium release from mouse calvaria in the presence of membrane IL-1. Indomethacin partially inhibited the bone resorption induced by membrane IL-1 on P388D1 cells. Moreover, membrane IL-1 on LPS-stimulated BALB/c mouse peritoneal macrophages or LPS-stimulated osteoblastic cells from BALB/c mouse calvaria induced bone resorption in vitro. These results suggest that membrane IL-1 on macrophages and osteoblastic cells may have a significant role in inflammatory bone resorption in vivo.

Animals↗
PubMed1989

T cells against a bacterial heat shock protein recognize stressed macrophages.

Heat shock proteins are evolutionarily highly conserved polypeptides that are produced under a variety of stress conditions to preserve cellular functions. A major antigen of tubercle bacilli of 65 kilodaltons is a heat shock protein that has significant sequence similarity and cross-reactivity with antigens of various other microbes. Monoclonal antibodies against this common bacterial heat shock protein were used to identify a molecule of similar size in murine macrophages. Macrophages subjected to various stress stimuli including interferon-gamma activation and viral infection were recognized by class I-restricted CD8 T cells raised against the bacterial heat shock protein. These data suggest that heat shock proteins are processed in stressed host cells and that epitopes shared by heat shock proteins of bacterial and host origin are presented in the context of class I molecules.

Animals↗
PubMed1989

Homology between surface protein antigen genes of Streptococcus sobrinus and Streptococcus mutans.

The structural gene (pag gene) for a 210 kDa protein antigen of Streptococcus sobrinus serotype g was cloned and compared with that (pac gene) of a 190 kDa protein antigen of Streptococcus mutans serotype c. Immunodiffusion analysis revealed that the product of the pag gene immunologically cross-reacted with that of the pac gene. Southern blot and nucleotide sequence analyses revealed that a significant homology existed between the middle regions of the two structural genes.

Amino Acid Sequence↗
PubMed1989

Antibody response against a possible arthritogenic epitope on human type II collagen induced by anti-idiotypic antibody.

We reported the presence of three distinct epitopes commonly present on murine and human type II collagen (CII), observed using mAb. To investigate the possible involvement of these epitopes in collagen-induced arthritis, we raised rabbit anti-idiotypic antibodies that may bear the internal image of these epitopes. Anti-idiotypic antibodies developed against three anti-CII mAb designated as 1-5, 2-14, and 2-15 were demonstrated to recognize idiotype expressed on Ag-binding site (paratope) of their related mAb. Anti-CII antibody response specific for a given epitope could be induced in DBA/1J mice upon immunization with anti-idiotypic antibodies coupled to keyhole limpet hemocyanin. Anti-idiotypic antibody to 1-5 antibody in particular could stimulate all DBA/1J mice for production of anti-CII antibody possessing Ag specificity and idiotype similar to those of 1-5 antibody. Although the mice immunized with anti-1-5 antibody alone did not develop arthritis, they did show a much more enhanced antibody response against a given epitope than did control mice non-treated with anti-idiotypic antibody upon the subsequent immunization with human CII. Some of the mice immunized with anti-1-5 antibody and challenged with human CII developed arthritis, whereas the control mice did not. These findings strongly suggest that a common epitope recognized by 1-5 antibody might be involved in the induction of arthritis.

Animals↗