Intranasal immunization with C5a peptidase prevents nasopharyngeal colonization of mice by the group A Streptococcus

Early inflammatory events are initiated by phased production of C5a and interleukin-8 in tissue. Most serotypes of group A streptococci express a surface-bound peptidase (SCPA) which specifically cleaves mouse and human C5a chemotaxins. This study investigates the impact of SCPA on colonization of the nasopharyngeal mucosa of mice and evaluates its potential to induce protective immunity. Two strains, serotypes M6 and M49, which contain insertion and deletion mutations in the SCPA gene (scpA) and represent the two major subdivisions of group A streptococci, were characterized and compared in a mouse intranasal infection model. In this model, SCPA mutants were more rapidly cleared from the nasopharynges of inoculated mice compared with wild-type strains. A 2,908-bp fragment of scpA49 gene, obtained by PCR, was ligated to the expression vector pGEX-4T-1 and expressed in Escherichia coli. The affinity-purified deltaSCPA49 protein proved to be highly immunogenic in mice and rabbits. Although the purified deltaSCPA49 immunogen lacked enzymatic activity, it induced high titers of rabbit antibodies which were able to neutralize peptidase activity associated with M1, M6, M12, and M49 streptococci in vitro. This result confirmed that antipeptidase antibodies lack serotype specificity. Intranasal immunization of mice with the deleted form of the SCPA49 protein stimulated significant levels of specific salivary secretory immunoglobulin A (IgA) and serum IgG antibodies and reduced the potential of wild-type M1, M2, M6, M11, and M49 streptococci to colonize. These experiments suggest a new approach to vaccine development for prevention of streptococcal pharyngitis.

[Studies on peripheral blood stem cells mobilization by short course and high-dose G-CSF]

OBJECTIVE

To explore the effect of short-course, high dose granulocyte-colony stimulating factor (G-CSF) on peripheral blood stem cell (PBSC) mobolization.

METHODS

G-CSF 5microg/kg was injected subcutaneously twice daily for 3 consecutive days. On the first day and the fourth day the peripheral blood and bone marrow were collected for CFU-GM, BFU-E, CFU-mix assays and CD34/CD38 detection. A single apheresis of over 8000ml blood processing was performed with CS-3000 blood cell separator. The mononuclear cells were prepared for hematopoietic colony assays and CD34/CD38 detection before and after freezing.

RESULTS

After adminitration of G-CSF, the white blood cell count increased significantly. The CFU-GM, BFU-E, CFU-mix yields and CD34+ CD38+ cell and CD34+ CD38- cells also increased significantly (P<0.05). The median of mononuclear cells was 1.56 x 10(8)/kg. After one week freezing, the recovery of mononuclear cells, CFU-GM, BFU-E yields and CD34+ CD38+ cells were about 80% (P>0.05) and CFU-mix yields was 60%; The CD34+ CD38- cells were decreased compared with that of pre-freezing (P<0.05). The median of the reinfused mononuclear cells was 1.27 x 10(8)/kg,CFU-GM 6. 7 x 10(4)/kg, BFU-E 1.6 x 10(4)/kg, CFU-mix 0.32 x 10(4)/kg, CD34- CD38+ cells 1.6 x 10(6)/kg and CD34+ CD38- cells 0.23 x 10(6)/kg.

CONCLUSION

Short course and high-dose G-CSF can effectively mobilize the peripheral stem cells. The mononuclear cells, hematopoietic colonies and CD34/CD38 cells were satisfied for the peripheral stem cells rescue.

Photorefractive properties of iron-doped stoichiometric lithium niobate

The photorefractive properties of stoichiometric LiNbO(3) crystals with a small number of defect densities grown by the double-crucible Czochralski method are investigated and compared with the defect densities of commercially available congruent Fe-doped LiNbO(3) crystals. Two-wave-mixing experiments show that novel stoichiometric crystals exhibit larger photorefractive gain and considerably faster response times than congruent ones. The results indicate that the nonstoichiometry defect control of photorefractive crystals is of key importance for the improvement of their properties.

Familial occurrence of hemangioblastoma of central nervous system

OBJECTIVE

To study the familial occurrence of hemangioblastoma of the central nervous system and to search for an effective way to diagnose and manage the disease.

METHODS

From 1974 to 1993, six patients with hemangioblastoma with family history underwent surgical treatment at our hospital. Computerized tomography (CT) or magnetic resonance imaging (MRI) technique was used for the diagnoses before operation.

RESULTS

Each patient had more than two relatives with hemangioblastoma. Multiple lesions were found in two of the six familial hemangioblastoma cases. All the patients recovered well after operation. So far, no victims have been discovered in the third generation.

CONCLUSIONS

The high occurrence rate of familial hemangioblastoma cases suggests an involvement of hereditary factors. We need a long follow-up study on the descendants of familial hemangioblastoma patients. MRI is of diagnostic value in determining the location and nature of hemangioblastoma in both brain and spinal cord. A thorough examination is necessary for hemangioblastoma patients, and microsurgery is important in removing the tumor.

Use of meiotic FISH for identification of a new monosome in Gossypium hirsutum L

The extensive use of molecular cytogenetics in human genetics and clinical diagnostics indicates that analogous applications in plants are highly feasible. One sort of application would be the identification of new aneuploids, which traditionally involves either direct karyotypic identification, which is feasible in only a few plant species, or tests with markers (cytogenetic, genetic, or molecular), which require sexual hybridization and at least one subsequent seed or plant generation. We have used meiotic fluorescence in situ hybridization (FISH) to analyze a new monosome of cotton (Gossypium hirsutum L., 2n = 4x = 52, 2(AD)1) that had a phenotype which seemed to be distinct from monosomes in the Cotton Cytogenetic Collection. Painting with A2-genome DNA revealed the monosome's D-subgenome origin. DAPI-PI staining showed that the monosome carries a major NOR, delimiting it to the major NOR-bearing chromosomes of the D-subgenome, i.e., 16 or 23. Dual-color FISH with 5S and 18S-28S rDNAs indicated that the monosome contains separate major clusters of each of these two tandemly repeated rDNA elements, thus delimiting the monosome to chromosome 23, for which the Cotton Cytogenetic Collection has previously been devoid of any sort of deficiency. Of the 26 chromosomes in the cotton genome, the Collection now provides coverage for 16 (70%) in the form of monosomy, and 20 (77%) in the form of monosomy and (or) telosomy. Use of molecular cytogenetic methods to identify a new plant aneuploid in cotton exemplifies the fact that a physicochemical karyotypic chromosome identification system is not required a priori for application of new molecular cytogenetic methods, thus indicating their potential applicability to nearly all plant species.

Subunit specificity and organ distribution of glutathione transferase-catalysed S-nitrosoglutathione formation from alkyl nitrites in the rat

Glutathione transferase (GST)-catalysed S-nitrosoglutathione (GSNO) formation from alkyl nitrites was determined with the homodimers 1-1, 2-2, 3-3, and 4-4 isolated from rat liver. The 4-4 isoform showed a high specificity for the alkyl nitrites. Total GST activities were studied in homogenates from different organs. The liver showed highest GST activity both with amyl nitrite and with 1-chloro-2,4-dinitrobenzene (CDNB) as substrate, the activity ratio of amyl nitrite over CDNB being 3.8. In lung and heart, these ratios were 6.2 and 5.7, respectively, indicating a selectivity of these organs for alkyl nitrite metabolism and GSNO formation.

Protein engineering on subtilisin E

Protein engineering was carried out by site-directed and random mutagenesis on subtilisin E gene. Four mutants were obtained. They are M222A; M222A, N118S; M222A, N118S, Q103R; and M222A, N118S, Q103R, D60N. The mutant genes were recombined in pBE-2, an E. coli-B. subtilis shuttle vector, and transformed into B. subtilis DB104, an alkaline and neutral proteinase deficient strain. The subtilisin E mutations obtained from their gene expressions were purified. The properties of these mutants showed that the M222A mutation made the enzyme resistant to oxidation, N118S mutation increased the thermal stability, while Q103R and D60N mutations enhanced the specific activity of the enzyme but decreased the thermal stability and, in particular, D60N mutation caused the enzyme to be very unstable. The IEF-PAGE showed that the wild type and M222A mutant had the same pI of 8.92, while those of double mutant, triple mutant, and quadruple mutant were 8.88, 9.10, and 9.17, respectively. The optimum pH range was 7.5-9.5 for suc-AAPF-pNA substrate and was 10-12 for casein substrate.

Characterization of the tumor invasion area in the rat intracerebral glioma

Tumor cell invasion surrounding intracerebrally implanted tumors in rats was studied by comparing the results of cerebral microangiography, fluorescence imaging of blood-brain barrier (BBB) disruption and histopathology. Each comparison was on subsequent sections taken from an initial 1 mm coronal slice of brain taken through the cell injection site containing tumor using the RT-2 glioma model. Tumor extension was assessed at 3, 5, 7 and 9 days after tumor implantation. Analysis of the brain adjacent to tumor shows that the actual tumor cell invasion area is greater than the area of BBB disruption at later stages of tumor growth and the extent of tumor vascularization lies well within the area defined by the extent of tumor cell invasion. Furthermore, this study found that the size of the area of tumor cell invasion remains relatively stable in proportion to the solid tumor mass at various stages of growth such that the area of tumor invaded brain was approximately 2.5 times greater than the area outlined by solid tumor mass. We conclude that measurement of the solid tumor mass, tumor vascular area and region of blood-brain barrier disruption due to tumor, grossly underestimate the total tumor volume. Therapies aimed at controlling glial tumor growth must, therefore, include normal appearing regions of brain peripheral to the abnormal region defined as tumor and tumor invaded brain as defined by radiographic and imaging studies.

[High-dose chemotherapy supported by peripheral blood stem cells to treat intermediate--and high-grade non-Hodgkin's lymphomas]

In this study, 16 eligible patients with intermediate and high-grade non-Hodgkin's lymphoma were treated with a new high-dose DHACT regimen supported by rhG-CSF and peripheral blood stem cell (PBSC) rescue. PBSC were mobilized by rhG-CSF or rhGM-CSF. Single leukapheresis was performed and the PBSC were then frozen in liquid nitrogen. CFU-GM clonogenic assay for mononuclear cells and resuscitated progenitor cells done to calculate how many progenitor cells were alive after freezing. The DHACT chemotherapy was composed of carboplatin 600 mg/m2 on d1, Ara-C 1500 mg/m2 on d2, VM-26 100 mg/m2 on d3, 4, and dexamethasone 40 mg/d, on d1-4. Autologous PBSC was reinfused after 24 to 48 hours of chemotherapy. Recombinant human G-CSF at 300 micrograms administered daily on 2 successive days when the absolute neutrophil count was greater than 1 x 10(9)/L. Other supportive care procedures were standard for the unit. The median amount of PBSC reinfused into a patient was 0.9 x 10(8)/kg. The recovery rate of CFU-GM was 78% after cryopresevation. Within 7 to 9 days after high-dose DHACT chemotherapy, the WBC count and the platlet count arrived nadir, and then rose gradually with rhG-CSF injection. The median time for WBC count from nadir to > or = 1 x 10(9)/L was 4 days, and that for platelet count from nadir to > or = 50 x 10(9)/L was 7 days. Nine patients achieved complete remission and 5 patients achieved partial remission. The median follow-up on survival was 9 months. High-dose DHACT regimen supported by rhG-CSF and PBSC rescue is a safe and effective treatment for patients with advanced intermediate and high-grade non-Hodgkin's lymphoma.

Presenilin-1 polymorphism in patients with Alzheimer's disease, vascular dementia and alcohol-associated dementia in Japanese population

We investigated the genetic association between intronic polymorphism in Presenilin-1 (PS-1) gene and patients with various types of dementia such as Alzheimer's disease (AD), vascular dementia (VD) and alcohol associated dementia (ALD), in Japanese population. Homozygosity for allele 1 of the PS-1 polymorphism was significantly increased in late-onset sporadic AD, but not in early-onset sporadic AD, familial AD, VD and ALD. When late-onset sporadic AD patients were divided on the basis of apolipoprotein E (APOE) genotype, homozygosity for the allele 1 of the PS-1 polymorphism was significantly increased in patients with late-onset sporadic AD without APOE epsilon 4 allele, but not in those with APOE epsilon 4 allele. Intronic mutation in PS-1 gene may be specific and one of the genetic risk factor for late-onset sporadic AD.

Role of intracardiac angiotensin II in cardiac dysfunction of rat during septic shock

OBJECTIVE

To observe changes in the content of myocardial angiotensin II and its role in cardiac dysfunction of rat during septic shock.

METHODS

Septic shock model was produced by cecal ligation and puncture (CLP) operation on rats. Experimental rats were given captopril 15 mg.kg-1/d per os for 3 days before CLP operation. Mean blood pressure and left ventricular pressure were recorded. Myocardial angiotensin converting enzyme (ACE) activities were determined by a fluorometric assay and myocardial angiotensin II content was measured by radioimmunoassay. Highly purified membrane of sarcoplasmic reticulum (SR) was prepared from rat hearts. Assays were made of ATP-dependent Ca2+ uptake by cardiac SR and (3H) ryanodine binding to SR.

RESULTS

Myocardial angiotensin II content increased by 51.5% (P < 0.01) at the 18th hour post CLP, meanwhile there was a decrease in left ventricular +/- dp/dtmax value and the impairment in Ca2+ uptake and (3H) ryanodine binding to cardiac SR. Preliminary administration of captopril reduced myocardial ACE activity and angiotensin II content, but increased left ventricular +/- dp/dtmax value. In comparison to shock group, the initial rate and the capacity of SR Ca2+ uptake were increased by 120% (P < 0.01) and 33.9% (P < 0.05), the Bmax value of (3H) ryanodine binding to SR was also elevated, while the Kd value remained unchanged.

CONCLUSIONS

The elevated intracardiac angiotensin II, resulting from the activation of myocardial ACE during sepsis, probably serves as one of the important mediators participating in the pathogenesis of heart failure: the effects of angiotensin II may be associated with the disturbance of Ca2+ transport function of cardiac SR.

[Effects of Peucedanum praeruptorum extractum on blood pressure, left ventricular hypertrophy and hemodynamic changes in left ventricular hypertrophied hypertensive rats]

After intragastric administration of Peucedanum praeruptorum (PPE) 0.6 g/100 g body weight, the blood pressure was decreased significantly in both the normal and the left ventricular hypertrophied hypertensive (LVH) rats. The PPE could still prevent the formation of the left ventricular hypertrophy in renovascular hypertensive rats, the ratio of weight of left ventricular over the weight of body was reduced markedly than that of the LVH group, and was nearly the same of the sham-operated group. The PPE could improve both the systolic and diastolic function than that of the LVH group in the isolated heart, especially, the flow of the coronary artery was increased significantly.

Distribution of 5S and 18S-28S rDNA loci in a tetraploid cotton (Gossypium hirsutum L.) and its putative diploid ancestors

The most widely cultivated species of cotton, Gossypium hirsutum, is a disomic tetraploid (2n=4x=52). It has been proposed previously that extant A- and D-genome species are most closely related to the diploid progenitors of the tetraploid. We used fluorescent in situ hybridization (FISH) to determine the distribution of 5S and 18S-28S rDNA loci in the A-genome species G. herbaceum and G. arboreum, the D-genome species G. raimondii and G. thurberi, and the AD tetraploid G. hirsutum. High signal-to-noise, single-label FISH was used to enumerate rDNA loci, and simultaneous, dual-label FISH was used to determine the syntenic relationships of 5S rDNA loci relative to 18S-28S rDNA loci. These techniques provided greater sensitivity than our previous methods and permitted detection of six new G. hirsutum 18S-28S rDNA loci, bringing the total number of observed loci to 11. Differences in the intensity of the hybridization signal at these loci allowed us to designate them as major, intermediate, or minor 18S-28S loci. Using genomic painting with labeled A-genome DNA, five 18S-28S loci were localized to the G. hirsutum A-subgenome and six to the D-subgenome. Four of the 11 18S-28S rDNA loci in G. hirsutum could not be accounted for in its presumed diploid progenitors, as both A-genome species had three loci and both D-genome species had four. G. hirsutum has two 5S rDNA loci, both of which are syntenic to major 18S-28S rDNA loci. All four of the diploid genomes we examined contained a single 5S locus. In g. herbaceum (A1) and G. thurberi (D1), the 5S locus is syntenic to a major 18S-28S locus, but in G. arboreum (A2) and G. raimondii (D5), the proposed D-genome progenitor of G. hirsutum, the 5S loci are syntenic to minor and intermediate 18S-28S loci, respectively. The multiplicity, variation in size and site number, and lack of additivity between the tetraploid species and its putative diploid ancestors indicate that the behavior of rDNA loci in cotton is nondogmatic, and considerably more complex and dynamic than previously envisioned. The relative variability of 18S-28S rDNA loci versus 5S rDNA loci suggests that the behavior of tandem repeats can differ widely.

Separation of enantiomers of drugs by capillary electrophoresis. III. Beta-cyclodextrin as chiral solvating agent

Enantiomer separation by capillary zone electrophoresis was studied for a set of 34 chiral drugs. Keeping the concentration of beta-cyclodextrin as a chiral solvating agent as constant as possible led to the separation of seven enantiomeric pairs. Carvedilol, Tetryzoline, Tropicamide and Zopiclone gave a baseline separation, Chlorphenamine, Ketamine, and Orciprenaline a partial separation. Statistical analysis revealed that the best separation factors were observed for a medium degree of interaction with the cyclodextrin. A theory explaining this effect provides a helpful guideline for further optimization.

Evidence of hypoxia-inducible factor-1 in vascular endothelial and smooth muscle cells

The hypoxia-inducible element (HIE-1), a 50-bp region just 3' to the human erythropoietin gene, has been found to regulate transcription in cells that do not ordinarily synthesize erythropoietin. We hypothesized that the HIE-1 and associated protein factors may have a role in transcriptional regulation in hypoxic vascular tissues. Therefore, tissues of vascular origin were grown in culture and exposed to hypoxia (1% 02, 5% CO2, balance N2) or normoxia (21% O2, 5% CO2). Human microvascular endothelial cells (HMEC-1) studied with electrophoretic mobility shifting demonstrated that HIE-1 was bound to a protein induced by hypoxia in these cells. HMEC-1 and rat aortic smooth muscle cells (RASM) were transfected with the vector pGL2-HIE-1. HMEC-1 reporter gene expression was 3.7 +/- 0.5-fold increased at 12 hours and 3.7 +/- 1.3-fold increased at 24 hours by hypoxia. RASM reporter gene expression was 18.6 +/- 6.5-fold (SEM) increased at 12 hours and 2.0 +/- 0.7-fold increased at 24 hours by hypoxia. These findings provide indirect evidence of a hypoxia-inducible factor in vascular cellular transcriptional regulation.

Analysis of amyloid precursor protein mRNAs in skin fibroblasts in Down's syndrome

We examined amyloid precursor protein (APP) mRNAs expression in skin fibroblasts from Down's syndrome (DS) patients of different ages to determine the time of occurrence of abnormal splicing. The ratio of APP770 + 751 mRNA to APP695 mRNA (APP770 + 751/695) was significantly increased in the young DS group and adult DS group compared with the age-matched control groups (p < 0.01, p < 0.05), but no significant increase was observed in the aged DS group compared with the age-matched control group. These findings suggest that metabolic abnormalities of the APP gene occur at a very early stage of DS, at a mean age of about 5 years. Therefore, metabolic abnormalities of the APP gene are considered to appear at a very young age also Alzheimer's disease (AD). In this study, we confirmed that examination of the APP gene in skin fibroblasts might be useful for early diagnosis of AD.

Effects of Arg-Gly-Asp-Ser on Ca2+ transport of myocardial sarcoplasmic reticulum in rat septic shock

AIM

To study the effects of Arg-Gly-Asp-Ser (RGDS), a synthetic short peptide of fibrinogen degradation, on the Ca2+ transport function of cardiac sarcoplasmic reticulum in rat septic shock.

METHODS

RGDS 5 mumol.kg-1 was injected i.v. at 4 h and 14 h after cecal ligation and puncture (CLP) operation on rats. Highly purified membrane of sarcoplasmic reticulum (SR) was prepared from rat hearts. Assays were made of ATP-dependent Ca2+ uptake by cardiac SR and [3H] ryanodine binding to SR.

RESULTS

The initial rate and the capacity of SR Ca2+ uptake were increased by 104% (P < 0.01) and 12% (P < 0.05), respectively, paralleled by an increase in Ca(2+)-ATPase activity and a decrease in calcium accumulation of myo- cardium of septic rats, whereas the Bmax and Kd values of Ca2+ activated [3H]ryanodine binding to SR were unaffected after RGDS administration.

CONCLUSIONS

The results indicated that RGDS have cardioprotective effects of maintaining Ca2+ homeostasis of cardiac myocytes by enhancing SR Ca2+ uptake in rat septic shock.

C5a peptidase alters clearance and trafficking of group A streptococci by infected mice

Group A streptococcal C5a peptidase (SCPA) specifically cleaves the human serum chemotaxin C5a at the polymorphonuclear leukocyte (PMNL) binding site. This study tested the proposal that SCPA contributes to virulence by retarding the influx of inflammatory cells and clearance of streptococci during the first few hours after infection. To investigate the specific contribution of SCPA to the virulence of group A streptococci, scpA insertion and deletion mutants were created by directed plasmid insertion into scpA and gene replacement. The precise locations of insertion and deletion mutations were confirmed by PCR and DNA sequence analysis. The impact of mutation on virulence was investigated with a mouse air sac model of inflammation. Experiments evaluated clearance of streptococci from the air sac within 4 h after infection. SCPA- streptococci were cleared more efficiently than wild-type bacteria. Localization of streptococci in lymph nodes and spleens of infected mice revealed a significant difference between mutant and wild-type streptococci. PMNLs and other granulocytes that infiltrated the air sac were quantitated by single-color flow cytometry. The total cellular infiltrate was greater and PMNLs dominated the granulocytic infiltrates of air sacs inoculated with SCPA- mutant bacteria. The data obtained are consistent with the possibility that SCPA- streptococci are initially cleared from the site of infection primarily by PMNLs. Moreover, mutant and wild-type streptococci followed different paths of dissemination. SCPA- bacteria were transported to lymph nodes, whereas wild-type streptococci avoided transport to the lymph nodes and rapidly spread to the spleen.

Microsomal formation of S-nitrosoglutathione from organic nitrites: possible role of membrane-bound glutathione transferase

The formation of S-nitrosoglutathione (GSNO) from amyl nitrite and n-butyl nitrite was studied in rat liver microsomes, employing N-ethylmaleimide (MalNEt) as an activator and indomethacin as an inhibitor of microsomal glutathione S-transferase (GST). Rates were compared with GST activity measured with 1-chloro-2,4-dinitrobenzene (CDNB) as a substrate. MalNEt stimulated GST activity and the formation of GSNO from amyl nitrite and n-butyl nitrite about 10-fold. Increasing concentrations of indomethacin inhibited both reactions in parallel. N-Acetyl-L-cysteine but not L-cysteine could substitute for GSH. It is concluded that rat liver microsomal GST catalyses the formation of GSNO from amyl nitrite and n-butyl nitrite. The activity of the MalNEt-stimulated microsomal GST is calculated to be about 17 units/mg of enzyme with the alkyl nitrites and about 16 units/mg of enzyme with CDNB as a substrate, assuming that 3% of microsomal protein is GST. These rates are comparable with those obtained for cytosolic GSTs. Thus microsomal GST may play a significant role in the metabolism of alkyl nitrites in biological membranes.

[Effects of m-Nif and Nif on left ventricle hypertrophy in rats induced by partial ligation of abdominal aorta]

Partial ligation of the abdominal aorta of rats was adopted to induce left ventricle hypertrophy (LVH). The effects of m-nifedipine (m-Nif) and nifedipine (Nif) on prevention of hypertrophy and the possible mechanism were investigated. The wet weights of the left ventricle (WWLV) of the LVH group were increased compared with those of the sham operated group. After treatment with m-Nif and Nif for 4 wks, the WWLV decreased by 25% +/- 9% and 16% +/- 9%, respectively. The pressure-volume (P-V) curve of the hypertrophied group was markedly elevated, which means that the myocardial compliance was decreased, and the stiffness coefficient of the hypertrophied group was significantly elevated than that of the sham operated group, but the groups treated with m-Nif or Nif were significantly improved. The characteristics of the left ventricular myocardial DHP binding sites were studied. The results showed that the Kd and the Bmax were similar in the m-Nif, Nif and hypertrophied groups, but the total number of the DHP receptors (TNR) of the LVH group was markly increased than that of the sham operated group, but the TNR of the m-Nif and Nif groups were the same as that of the sham operated group. These results suggest that the effects of m-Nif and Nif on preventing cardiac hypertrophy and improving myocardial compliance may be related to their depressing the TNR of DHP.