Genetically synthesized antibody-binding protein self-assembled on hydrophobic matrix

A unique antibody-binding protein, (E12B2)n, was genetically synthesized, which was characterized by a hydrophobic peptide, E12, at one terminus and an antibody-binding peptide, B2, at the other. It was clarified by atomic force microscopy (AFM) imaging that this protein was efficiently self-assembled on a hydrophobic solid surface. (E12B2)n self-assembled on a microplate exhibited an excellent performance of antibody-binding affinity. The proposed design of antibody-binding protein seems promising in immobilizing antibody molecules on hydrophobic solid surfaces.

[Bulbocavernosus reflex induced by bladder filling in a neurogenic bladder patient due to spinal arteriovenous malformation. A case report]

A 59-year-old man with spinal arteriovenous malformation at L-1 level was referred to our clinic for urinary retardation and urinary protraction. Bulbocavernosus reflex (BCR) was performed at empty bladder and at the storage phase during cystometry. BCR was evoked by compressing the glans penis. The evoked reflexes were examined by palpatating the contractile responses of the bulbocavernosus muscle and bipolar surface electrodes on each side of para-perineal raphe. Evoked response of BCR couldn't be detected at empty bladder, but obvious responses of BCR were detected at about 300 ml bladder filled. For further evaluation, a concentric needle electrode was inserted into the periurethral striated muscle to examine the evoked potential of BCR. The responses were unstable at empty bladder, but stable evoked potentials were obtained at storage phase. BCR performed only at empty bladder may cause false negative result.

Measurement of blood clearance time by Limulus G test of Candida-water soluble polysaccharide fraction, CAWS, in mice

The Limulus G test, responsive to beta-1,3-D-glucan, is a well-established method for the detection of invasive fungal infection. We have recently found that Candida albicans released a water-soluble polysaccharide fraction (CAWS) into synthetic medium (Uchiyama et al., FEMS Immunol. Med. Microbiol. 24 (1999) 411-420). CAWS was composed of a mannoprotein-beta-glucan complex and activated Limulus factor G, and thus would be similar to the Limulus active substance in patient's blood. In a preliminary investigation, we have found that CAWS is lethal when administered intravenously in a murine system. In this study, we examined the toxicity and then the fate of CAWS in mice. The lethal toxicity was strain-dependent and strain DBA/2 was the most resistant. The toxicity was, at least in part, reduced by salbutamol sulfate and prednisolone treatment in the sensitive strains. On intravenous administration, the half clearance time (t1/2) was approximately 40 min in mice (DBA/2). On intraperitoneal administration, CAWS appeared in the blood with a peak concentration at 1 h. In order to establish a treatment plan, it is important to demonstrate the onset and the termination of deep-seated mycosis. The Limulus G test is suitable for the above purpose; however, it is necessary to fully understand the fate of beta-1,3-D-glucan in patients' blood.

Extracorporeal shock wave lithotripsy for a ureteral stone in crossed fused renal ectopia

BACKGROUND

A 63-year-old woman presented with right flank pain and macroscopic hematuria.

RESULTS/METHODS

A plain film showed a calcific shadow on the right iliac bone. On excretory urography, the right kidney was seen in the normal position, but the left kidney was not. Bilateral retrograde pyelogram revealed the S-shaped kidney and mild obstruction from a 12 x 5 mm calculus in the proximal ureter of the crossed kidney. The patient was successfully treated with in situ extracorporeal shock wave lithotripsy (ESWL) treatment and is stone free at 1 month follow up.

CONCLUSION

We believe this is the first case of successful ESWL in a crossed kidney.

Genetically fused protein A-luciferase for immunological blotting analyses

The gene expression plasmid pMALU5 for the fusion protein of protein A (SpA) with a complete sequence of firefly luciferase (Luc) was constructed. The fused gene was expressed in Escherichia coli, and the resulting SpA-Luc fusion protein was purified by one-step affinity chromatography on IgG-Sepharose. The protein retained both activities: IgG binding capability of protein A and enzymatic activity of luciferase. Blotting analyses were performed with the fusion protein to determine a tumor marker of alpha-fetoprotein (AFP). AFP was detected at the lowest detection limit of 5 pg by dot blotting and Western blotting. The SpA-Luc fusion protein provides a highly selective, sensitive, and versatile marker for blotting analyses.

Electrically stimulated induction of hsp70 gene expression in mouse astroglia and fibroblast cells

Mouse astroglial cells, which were cultured on an electrode, were found responsive to an electric stimulation of sine wave potential in enhancing hsp70 mRNA resulting from an activation of hsp70 gene expression. On the basis of this finding, electrically responsive cells were established by transfecting mouse 3T3-L1 cells with a constructed plasmid encoding hsp70 promoter and the firefly luciferase gene. A stable cell line has been established through selection of heat-stimulated luciferase expression. A 1-h electric stimulation of the cells resulted in activation of luciferase expression, which was confirmed to produce an increase in light emission. The sequential pattern of the electrically stimulated expression of luciferase was found different from that of the heat stimulation. Furthermore, the promoter was activated depending on the potential and duration of the stimulation applied. Consequently, the electric stimulation has proven effective on activating hspP70 promoter. This cell line is feasible in expressing the gene of interest by electrical stimulation, which lead us to construct environment responsive cells in general.

New approach to transport improvement in a helical magnetic axis system by introduction of effective toroidal curvature

A new approach to transport improvement in a helical magnetic axis stellarator is proposed. First of all, the proposal is presented for the L = 1 system. The effective toroidal curvature term epsilon(T), defined as the sum of the usual toroidal curvature and one of the nearest satellite harmonics of the helical field, determines confinement conditions of localized trapped particles. There exists a certain correlation between the smallness of epsilon(T) and the omnigeneity. This approach would give rise to the possibility of a stellarator design study in a wider parameter domain than quasisymmetry approaches.

Single-molecular AFM probing of specific DNA sequencing using RecA-promoted homologous pairing and strand exchange

The specific sequence in a linearlized double-stranded DNA target has been identified at a single-molecular level by atomic force microscopy (AFM). This was accomplished using RecA-coated, single-stranded DNA probes which were paired with a specific complementary DNA sequence in a linear double-stranded DNA target by strand-exchange reaction at a homologous sequence site with target DNA. The sites of interaction between the nucleoprotein filaments and the double-stranded DNA targets were directly visualized by AFM in solution containing 4 mM magnesium acetate. Measurements of the position of RecA-coated probes paired to individual target DNA showed that DNA probes specifically paired at their corresponding homologous target sequences. Strand exchange promoted by RecA and the visualization by AFM provided a rapid and efficient way to identify homologous sequence on a single-molecule target DNA.

Osteogenesis coordinated in C3H10T1/2 cells by adipogenesis-dependent BMP-2 expression system

A novel tissue engineering for bone formation has been proposed, to make osteoblast differentiation balanced by transfecting the mesenchymal stem cells with a gene encoding human bone morphogenetic protein-2 (hBMP-2) under the control of adipocyte specific lipoprotein lipase (LPL) promoter. Due to the promoter specificity, the initiation of BMP transcription is dependent on adipogenesis. For 14-day culture in the presence of ascorbic acid (asc) and beta-glycerophosphate (gly), nontransfected mouse embryonic fibroblast C3H10T1/2 (10T1/2) cells showed extensive accumulation of lipid droplets and adipocyte specific enzyme glycerol-3-phosphate dehydrogenase (G3PDH) mRNA expression, but exhibited neither BMP-2 expression, high alkaline phosphatase (ALP) activity which reflects osteoblast phenotype. On the other hand, transfected 10T1/2 cells showed hBMP-2 expression, high ALP activity and low level of G3PDH. mRNA expression accompanied with minimal lipid droplets. These results indicate that 10T1/2 cells are proved to be differentiated with maintaining coordinated balance of adipogenesis and osteogenesis, when they are transfected by the gene encoding hBMP-2 under the control of LPL promoter.

Assembling of engineered IgG-binding protein on gold surface for highly oriented antibody immobilization

The B-domain, which is one of IgG-binding domains of staphylococcal protein A, was repeated five times and a cysteine residue was introduced at its C-terminus by a genetic engineering technique. The resulting protein, designated B5C1, retained the same IgG-binding activity as native protein A. The B5C1 was assembled on a gold plate surface by utilizing a strong affinity between thiol of cysteine and a gold surface. IgG-binding activity of B5C1 on a gold surface was much higher than that of physically adsorbed B5, which lacks cysteine residue. Furthermore, antigen-binding activity of immobilized antibody molecules through the use of assembled B5C1 on a gold surface was about 4.3 times higher than that of physically adsorbed antibody molecules. Immobilization of highly oriented antibody molecules was realized with the engineered IgG-binding protein.

Effects of body position on blood gases and lung mechanics of infants with chronic lung disease during tube feeding

BACKGROUND

The effects of body position and feeding on lung mechanics and blood gases in very low birthweight infants with chronic lung disease (CLD) is not fully elucidated.

METHODS

Seven very low birthweight infants who were being mechanically ventilated because of CLD were examined. They were enrolled in this study when their feeding volume exceeded 100 mL/kg per day. Each patient was kept on the same position (either prone or supine) during feeding. Feeding was given by a nasogastric tube for over 1 h every 3 h. Blood gases and lung mechanics were evaluated before, 20 min and 40 min after the initiation of the feeding and at the end of the feeding.

RESULTS

The prone position resulted in a significant increase in arterial oxygen saturation during feeding. The tidal volume in the prone position was significantly larger than in the supine position only before feeding. There were no significant differences in minute ventilation between these positions during the study. Pulmonary resistance was not different in either position, but the static compliance and the work of breathing of spontaneous breaths were improved significantly when the infants were in the prone position. In the supine position, work of breathing increased and static compliance decreased significantly with time, while in the prone position, those values did not change significantly.

CONCLUSION

The improvement in lung mechanics may partly explain better oxygenation obtained in the prone position. The prone position could decrease energy expenditure for spontaneous breathing and may shorten the period of ventilatory support for very low birthweight infants with CLD.

[Electromyographic study of the striated urethral sphincter by using the bulbocavernosus reflex: study of the normal voluntary voiding and the involuntary sphincter relaxation]

PURPOSE

The aim of this study was to investigate the sacral reflex activity at the striated urethral sphincter relaxation by evoking the potential of the bulbocavernosus reflex (BCR).

METHODS

17 normal male subjects were investigated. BCR was elicited by electrical stimulation of dorsal nerve of the penis, and the evoked potential of the BCR (BCR-EP) was recorded by a concentric needle electrode at the periurethral striated muscle. In normal subjects BCR was performed at rest and during voluntary voiding. In 8 of the normal subjects electrical stimulation was increased gradually during voluntary voiding, and changes of BCR-EP were studied. 3 male patients with neurogenic bladder suffering from urinary incontinence caused by involuntary sphincter relaxation (IVSR) were also investigated. In these patients with neurogenic bladder, BCR was performed at rest and during voluntary voiding as well as during involuntary voiding.

RESULTS

In the normal subjects stable BCR-EP was elicited at rest and disappeared during voluntary voiding. But a gradually increased larger stimulation clearly demonstrated BCR-EP during voluntary voiding. In 3 patients with neurogenic bladder, stable ECR-EP was elicited at rest. During involuntary voiding caused by IVSR obvious BCR-EP was also elicited, but its amplitude was slightly less than the amplitude of BCR-EP at rest. During voluntary voiding in 2 of the 3 patients BCR-EP was recognized but the amplitude was much less, and in the third patient BCR-EP could not be recognized.

CONCLUSION

BCR-EP was suppressed during voluntary voiding in normal subjects, but insufficiently suppressed in the patients with neurogenic bladder. In these patients BCR-EP during voluntary voiding was suppressed more distinctly than BCR-EP during involuntary voiding due to IVSR. In urodynamic study, the detrusor contraction and the sphincter relaxation were common phenomenon in both voluntary voiding and involuntary voiding, but the difference in the degree of the BCR suppression depended on whether micturition was voluntary or involuntary. It was suggested that the measurement of BCR-EP could distinguish involuntary voiding caused by pathological urethral sphincter relaxation from voluntary voiding.

Bioluminescent monitoring of intracellular ATP during fermentation

The luciferase gene was introduced as a probe into a cell in order to develop a bioluminescent monitoring of intracellular ATP during fermentation. Two plasmids were constructed with two types of promoters. One was pLac-Luc, which had the luciferase gene under the lac promoter to be expressed at a high level. The other was pTet-Luc, which had the luciferase gene under the tetracycline promoter to be stably expressed. A threonine-overproducing strain of Escherichia coli (No. 29-4) was transformed with each plasmid. The recombinant E. coli strains were characterized in their growth, threonine production and luciferase expression. The bioluminescence produced intracellularly from expressed luciferase was detected during fermentation -in a non-destructive manner. The bioluminescent intensity reflected both intracellular ATP and luciferase levels, and the results indicate that stable expression of a luciferase reporter is essential for monitoring intracellular ATP.

Site-directed lipid modification of IgG-binding protein by intracellular bacterial lipoprotein process

IgG-binding protein was genetically expressed and lipid-modified in a site-directed manner in Escherichia coli. The DNA sequence encoding the signal peptide and the nine N-terminal amino acid residues of the major lipoprotein of E. coli (lpp) was fused to the sequence of B-domain which was one of the IgG binding domains of Staphylococcal Protein A (SpA). The N-terminal cysteine residue of the resulting protein was enzymatically linked with lipids in the bacterial membrane. The lipid-modified protein was translocated at the bacterial membrane in a manner similar to native bacterial lipoprotein, and it was purified with IgG-Sepharose by affinity chromatography. The lipid modified proteins (lppB1 and lppB5) showed a similar IgG binding activity to unmodified proteins, which was estimated by competitive ELISA. Proteoliposomes of lipid modified proteins were prepared in an elegant fashion so that the IgG binding site should be properly oriented on the surface of an individual liposome by anchoring the lipid-tail into the hydrophobic layer of the liposome membrane. As compared with the unmodified one, the lipid modified protein incorporated into the proteoliposome exhibited higher IgG binding activity.

In vitro selective RNA synthesis with L-A virus nanoparticles

New in vitro RNA synthesis has been performed with an L-A virus nanoparticles, in which the gene and polymerase are integrated. The specific recognition sequence (packaging site) of L-A virus was inserted within a gene of interest. Based on the intrinsic replication cycle, the exogenous RNA with the packaging site was encapsulated by an empty L-A virus nanoparticle. The packaging site worked as a recognition site even for exogenous RNAs. The recognized RNA was replicated to dsRNA, and was then transcribed by empty L-A virus nanoparticles. These results indicate that empty L-A virus nanoparticles recognize an exogenous RNA with the packaging site and synthesize RNA in vitro.

[The application of the endotoxin test for globulin and other blood products]

The application of the endotoxin test for globulin and other blood products were investigated by two different limulus amebocyte lysate (LAL) test methods, colorimetric and kinetic turbidimetric methods, using two endotoxin-specific reagents. By the dilution of the blood products in 40 times or more, spiked endotoxin in the products was recovered accurately showing neither inhibition nor enhancement. The definite difference was not shown between the results obtained by the two LAL test methods. According to the method of the endotoxin test described under General Tests of The Japanese Pharmacopeia (thirteenth edition), JPXIII, the maximum valid dilution (MVD) for these products will be calculated to be 40 or more, so it is capable to measure the endotoxin limit for each product. This study indicates that the endotoxin test is applicable to measure the endotoxin content in globulin and other blood products as an alternative method for the rabbit pyrogen test.

Characterization of quinolone antibacterial-induced convulsions and increases in nuclear AP-1 DNA- and CRE-binding activities in mouse brain

The quinolone antibacterials enoxacin and norfloxacin (2.5 mg/kg, i.v.) provoked clonic convulsions in mice treated concomitantly with biphenylacetic acid (BPAA, 100 mg/kg, i.p.), a major metabolite of the nonsteroidal anti-inflammatory drug fenbufen. Gel-shift assays showed that enoxacin-induced convulsions resulted in increases in nuclear activator protein 1 (AP-1) DNA- and cyclic AMP responsive element (CRE)-binding activities in the cerebral cortex and hippocampus, but not in other regions, such as the cerebellum and thalamus. In contrast, ofloxacin and levofloxacin, at the same doses, in the presence of BPAA did not evoke convulsions or increase these DNA-binding activities. Administration of these quinolones and BPAA alone elicited neither convulsions nor increases in these DNA-binding activities. These results suggest that the increased nuclear AP-1 DNA- and CRE-binding activities in the cerebral cortex and hippocampus induced by quinolones with BPAA correlated with seizure activities and that these brain regions play pivotal roles in quinolone-induced convulsions.

[Urinary disturbance in olivopontocerebellar atrophy (OPCA)--changes during the progression of the disease]

PURPOSE

Among spinocerebellar degeneration, syndromes categorized as multiple system atrophy (MSA) are commonly associated with neurogenic bladder, and urinary disturbances change with the disease progression. Accordingly, the changes in the urodynamic findings during the progression of the disease have been studied in the case of Olivopontocerebellar atrophy (OPCA) and OPCA type of MSA.

METHODS

Urodynamic study (UDS) was performed more than twice in eight patients (5 males, 3 females, age 48-76, mean 55.0). The interval range between the first examination and follow up examination was 9-93 months (mean 42.4). UDS included cystogram, intravenous pyelography, residual urine volume, cystometry, urethral pressure profilometry, and external sphincter electromyography.

RESULTS

The bladder was deformed in almost all patients with the progression of the disease, but the upper urinary tract was properly preserved. Residual urine volume tended to increase, and residual urine rate worsened significantly. The stable detrusor activity seemed to become overactive accompanied by detorusor hyperreflexia, and finally seemed to be acontractile. The normal sphincter activity seemed to become overactive accompanied by detrusor-sphincter dyssynergia, and finally complete relaxation could't be observed.

CONCLUSION

These results suggest that urinary disturbance deteriorates together with other neuropathies as the disease progresses in OPCA. These patients should be continuously observed along with proper urinary management depending on the disease progression.

Stabilization and translation of immobilized mRNA on latex beads for cell-free protein synthesis system

The stability of immobilized mRNA against ribonucleases was investigated in a cell-free protein synthesis system. The plasmid-encoding protein A with the 20-mer poly(A) tail under the control of T7 promoter was constructed, and the corresponding mRNA was synthesized by T7 RNA polymerase reaction. The resulting mRNA was immobilized on oligo(dT)-immobilized latex beads by hybridization utilizing the poly(A) tail of mRNA at the 3'-terminus. The mRNA was stabilized against three types of nucleases (3'-OH exonuclease, 5'-OH exonuclease, and endonuclease) by immobilization. Translation of immobilized mRNA with a continuous-flow cell-free protein-synthesizing system from Saccharomyces cerevisiae was ascertained. Reusability of the immobilized mRNA as genetic information was also examined.

Detection of local ATP release from activated platelets using cell surface-attached firefly luciferase

We have developed a method for measuring the local concentration of ATP at the extracellular surface of live cells. This method relies on the specific attachment to the cell surface of a chimeric protein that consists of the IgG-binding domain of Staphylococcus aureus protein A fused in-frame with the complete sequence for firefly luciferase (proA-luc). Expression of proA-luc in Escherichia coli and its one-step affinity purification are straightforward. Attachment to cells is demonstrated to be specific and antibody dependent using several suspended and adherent cell types. Light production by cell surface-attached luciferase is continuous, linearly related to ATP concentration, and sufficient to provide nanomolar sensitivity. The spatial resolution of this method enables the observation of strictly local changes in extracellular ATP during its secretion from activated platelets. Furthermore, the activity of cell-attached luciferase is relatively refractory to the inclusion of nucleotidases in the medium, arguing for its effectiveness in cell systems possessing potent ecto-ATPases.

Surveillance study for clinical stage I testicular seminomas and nonseminomatous germ cell tumors

BACKGROUND

Optimal therapy for stage I testicular tumors is still controversial. This study evaluated the efficacy of a surveillance policy for patients with testicular stage I seminomas and nonseminomatous germ cell tumors (NSGCT).

METHODS

From 1984 to 1996, 24 patients with stage I seminoma and 20 with stage INSGCT were followed after radical orchiectomy with tumor markers and imaging studies. All patients were followed for at least 2 years except for those who recurred within 2 years. Recurrent patients were treated with cisplatin-based chemotherapy.

RESULTS

The median follow-up periods for seminoma and NSGCT patients were 41 and 54 months, respectively. Recurrences were detected in 2 seminoma (8.3%) and 10 NSGCT (50%) patients. Eleven of the 12 recurrent patients (92%) were detected within 2 years after orchiectomy. The seminoma patients both recurred in the retroperitoneal lymph nodes, while 70% of the NSGCT patients recurred in the lung and/or retroperitoneal lymph nodes. The recurrent seminoma patients were treated with chemotherapy and are alive without disease for 1 7 and 24 months afterorchiectomy. One NSGCT patient died of cancer, but the other 9 recurrent NSGCT patients are alive without disease at 25 to 113 months after orchiectomy.

CONCLUSIONS

Surveillance alone is reliable for monitoring patients with stage I testicular seminoma and NSGCT. The majority of recurrences occurred within 2 years, necessitating intensive follow-up for 3 years. As the lung metastatic rates in NSGCT patients were high, a more accurate assessment for lung metastasis is desirable in these patients.

Two types of electrochemical nitric oxide (NO) sensing systems with heat-denatured Cyt C and radical scavenger PTIO

To develop an in situ NO sensing system for primarily biological and medical uses, two types of NO sensing materials, which may be coupled with an electrochemical reaction for signal transduction, have been investigated. Heat-denatured Cyt C and a radical scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetra methyl imidazoline-1-oxyl-3-oxide (C-PTIO) were found to be effective and were incorporated into electrochemical sensing systems. Heat-denatured Cyt C deposited on a 4-mercaptopyridine modified gold electrode responded to NO with an increase of cathodic current through electrochemical reduction of Cyt C (Fe3+), when the electrode potential was controlled at 0 mV vs Ag/AgCl. The dynamic range of the sensing system was 0.5-4 microM. The sensing system with C-PTIO exhibited an anodic output in response to NO at 0.7 V vs Ag/AgCl, and showed a wider dynamic range from 0.05 to 100 microM.