In Vitro Biocompatibility of a New Titanium-29Niobium-13Tantalum-4.6Zirconium Alloy With Osteoblast-Like MG63 Cells

BACKGROUND

Titanium-29niobium-13tantalum-4.6zirconium (TiNb) has recently been developed as a new implant material. TiNb is composed of non-toxic elements and has a lower modulus of elasticity than the other titanium alloys. However, its biocompatibility has not been adequately characterized. The aim of this study was to evaluate the biocompatibility of TiNb using an osteoblast-titanium co-culture system.

METHODS

MG63 cells were cultured on three kinds of titanium disks: TiNb, pure titanium (pTi), and titanium-6aluminum-4vanadium (TiAl), prepared with two different surfaces, a polished and acid-etched surface and a machined-grooved surface. The surface topography and roughness were evaluated by scanning electron microscopy (SEM). After 48 hours culture, the number of proliferating cells and prostaglandin E2 (PGE2) production in the culture supernatant were determined.

RESULTS

There was no significant difference in surface roughness among the three titanium disks with a polished and acid-etched surface. After 48 hours of culture, the number of cells was significantly reduced on pTi and TiAl compared to TiNb and the control. PGE2 production was significantly higher on pTi than on TiAl, TiNb, and the control. We further examined the effect of surface roughness on PGE2 production using machine-grooved titanium disks. While pTi and TiAl stimulated the production of PGE2 depending on surface roughness, roughened TiNb did not affect PGE2 production.

CONCLUSIONS

These results suggest that TiNb may exhibit favorable biocompatibility because it has an efficient surface topography for cell proliferation, and the level of PGE2 production does not depend on surface roughness. We conclude that TiNb may be useful as an implant material.

Possible involvement of protein kinases and Smad2 signaling pathways on osteoclast differentiation enhanced by activin A

Bone tissues reportedly contain considerable amounts of activin A and follistatin, an activin A-binding protein. In the present study, we found that follistatin strongly inhibited osteoclast formation in cocultures of mouse bone marrow cells and primary osteoblasts induced by 1alpha,25 dihydroxyvitamin D(3), prostaglandin E(2), and interleukin-1alpha. Antibody aganist activin A also inhibited the osteoclast formation. Furthermore, activin A synergistically stimulated osteoclast differentiation mediated by receptor activator NF-kappaB ligand (RANKL). RT-PCR analysis revealed that osteoblasts produced not only activin A but also follistatin. Western blot analysis of a panel of phosphorylated proteins revealed that activin A stimulated the phosphorylation of p44/42 mitogen activated protein (MAP) kinase (ERK1/2) and p38 MAP kinase in macrophage colony-stimulating factor-dependent bone marrow macrophages (M-BMMPhis). In addition, phosphorylation of Smad2 was observed in M-BMMPhis stimulated with activin A. These findings indicate that the phosphorylation of p44/42 MAP kinase, p38 MAP kinase, and Smad2 is involved in activin A-enhanced osteoclast differentiation induced by RANKL. Taken together, these results suggest that both activin A and follistatin produced by osteoblasts may play an important role in osteoclast differentiation through MAP kinases and Smad2 signaling pathways.

Osteoclast differentiation is associated with transient upregulation of cyclin-dependent kinase inhibitors p21(WAF1/CIP1) and p27(KIP1)

Osteoclasts, bone-resorbing multinucleated cells, develop from monocyte-macrophage lineage cells in the presence of osteoclast differentiation factor (ODF, also called RANKL/TRANCE/OPGL) and macrophage colony-stimulating factor (M-CSF). M-CSF-dependent bone marrow macrophages (M-BMMPhis) from mouse bone marrow cells have been shown to differentiate into osteoclast-like multinucleated cells (OCLs) in the presence of soluble ODF/RANKL (sODF/RANKL) and M-CSF within 3 days. In this study, we found that stimulation of M-BMMPhis with sODF/RANKL induced a transient expression of cyclin-dependent kinase inhibitors (CDK inhibitors) p21(WAF1/CIP1) and p27(KIP1) by 24 h. The CDK inhibitor proteins disappeared by 48 h. Tumor necrosis factor alpha (TNF-alpha), which is reported to stimulate OCL differentiation, stimulated p21(WAF1/CIP1) and p27(KIP1) expression in M-BMMPhis as well. However, M-CSF alone did not stimulate the expression of the two CDK inhibitors. To clarify the role of p21(WAF1/CIP1) and p27(KIP1) in osteoclastogenesis, accumulation of these CDK inhibitors was aborted by antisense oligonucleotides. Treatment with p21(WAF1/CIP1) antisense oligonucleotide alone, or p27(KIP1) antisense oligonucleotide alone, showed a limited inhibitory effect on OCL formation. However, treatment with a mixture of these two antisense oligonucleotides strongly inhibited OCL formation. These results suggest that a combined modulation of the CDK inhibitors p21(WAF1/CIP1) and p27(KIP1) may be involved in osteoclast differentiation induced by ODF/RANKL.

Comparison of urine cytology between the ileal conduit and Indiana pouch

OBJECTIVE

To compare the cytomorphologic features of urine obtained from two different kinds of urinary diversions constructed after total bladder resection.

STUDY DESIGN

The smears of urine from 11 ileal conduits and 6 Indiana pouches were evaluated. All patients underwent total bladder resection due to transitional cell carcinoma (TCC) or other kinds of cancer before urine diversion.

RESULTS

The cytologic features of Indiana pouch urine include degenerated, small, round cells without columnar cells derived from intestinal epithelium. In ileal conduit urine, well-preserved columnar cells and degenerated, small, round cells were frequently observed. The columnar cells in ileal conduit urine exhibited cytologic features that should be distinguished from TCC cells.

CONCLUSION

The method of reconstructing the urinary tract is important in urine cytology from urine diversions because the cytomorphologic features of urine are different between the two kinds of urinary diversions. Since columnar cells in ileal conduit urine might lead to misdiagnosis as TCC, special consideration is required to examine ileal conduit urine.

Bone morphogenetic protein-2 enhances osteoclast formation mediated by interleukin-1alpha through upregulation of osteoclast differentiation factor and cyclooxygenase-2

Bone morphogenic protein-2 (BMP-2) is a member of the transforming growth factor beta (TGF-beta) superfamily. While BMP-2 is capable of inducing bone formation ectopically, little is known about its role on osteoclastogenesis. In this study, we examined the effect of BMP-2 on osteoclast-like multinucleated cell (OCL) formation in cocultures of osteoblast-like cells and hematopoietic cells of bone marrow origin. BMP-2 alone did not stimulate OCL formation in this culture system; however, it strongly enhanced OCL formation in a dose-dependent fashion in the presence of interleukin-1alpha (IL-1alpha). Western blot analysis showed that a simultaneous addition of BMP-2 and IL-1alpha synergistically enhanced cyclooxygenase-2 (COX-2) expression in osteoblast-like cells. Moreover, Northern blot analysis revealed that the level of osteoclast differentiation factor (ODF) mRNA increased by treatment with BMP-2 and IL-1alpha in osteoblast-like cells. It is noted that BMP-2 alone did cause an increase in the expression of both COX-2 and ODF genes. The stimulatory effect of BMP-2 was abolished by adding nonsteroidal anti-inflammatory drugs, such as indomethacin and a selective COX-2 inhibitor NS-398. Addition of NS-398 inhibited the expression of the ODF gene in osteoblast-like cells treated with BMP-2 and IL-1alpha. These results indicated that the combination of BMP-2 and IL-1alpha stimulated osteoblast-like cells to elevate the expression of both COX-2 and ODF genes, resulting in an enhanced OCL formation. Since BMP-2 alone induced the expression of COX-2 and ODF genes in osteoblast-like cells, it appears to be one of the regulating factors of osteoclastogenesis.

Assay of 222Rn in water samples by a modified integral counting method

22Rn activity concentrations in water collected from 163 private wells and 14 springs in Tokyo were measured with a liquid scintillation spectrometer using a modified integral counting method. The activity concentrations of 222Rn range from 0.2 to 22.9 Bq/L and average 4.8 Bq/L. The errors due to the air luminescence counts and the interferences from 220Rn and 219Rn are discussed and evaluated. 222Rn samples of 0.2 Bq/L can be assayed within an overall uncertainty of 3.1%. The liquid scintillation method involving agitation of the sample water directly with a liquid scintillation cocktail was compared with the present method and evaluated.

Cord blood IgE against milk and egg antigens

The aim of the present study was to reevaluate the prenatal production of specific IgE for eggs and milk and, in those cases, to determine whether there is a relation to the amount of maternal egg and milk intake. Total and specific IgEs from 160 cord blood-samples were determined by immunoassays using a paramagnetic particle solid phase and an enzyme-mediated chemiluminescent reaction for signal detection. The levels of cord blood IgE for total, egg, and milk were 0.63 +/- (SD) 1.10 IU/ml, 0.020 +/- 0.055, and 0.036 +/- 0.053 IU/ml, respectively. IgE levels specific to egg and milk over 0.03 IU/ml were observed in 33 and 70 out of 160 cases, respectively. To address whether the maternal intake of eggs and milk affects the level of cord blood IgEs, all mothers except 9 were interviewed, and the amount of eggs and milk taken during pregnancy was recorded. No correlation was seen between egg and milk intakes and cord blood IgE levels. Our data demonstrate a high incidence of the prenatal production of specific IgE for eggs and milk which is independent of maternal egg and milk intakes.

[Effect of posture strategies on preventing aspiration]

The purpose of this study was to determine the effect of postural change on preventing aspiration, and the types of swallowing disorder that were influenced by posture. Ninety-five patients that were examined by aspiration of barium during videofluoroscopic examination of oropharyngeal swallow assumed one of four postures (chin down, head rotation, chin down + head rotation, and head back to chin down). Postural strategies were successful in eliminating aspiration in 68(72%) of the 95 patients. Twenty five of the 68 patients, however, needed an additional change in bolus volume to eliminate aspiration. Effective postures eliminating aspiration were chin down for 43 patients, head rotation for 10 patients, chin down + head rotation for 12 patients, and head back to chin down for 3 patients. The successes rates of posture changes for each swallowing abnormality were 76% for reduced tongue base retraction, 74% for delay in triggering pharyngeal swallow, 74% for reduced laryngeal elevation, 73% for laryngeal paralysis, 68% for inefficient oral transit, and in 57% for cricopharyngeal dysfunction. Among individuals with cricopharyngeal dysfunction or with than three swallowing motility problems, the frequency of unsuccessful swallow despite postural change was significantly higher than that of successful swallow. These results indicated that the posture strategies in addition to control of bolus volume could prevent aspiration in more than 70% of patients, but the efficacy of posture techniques differed with the different types of swallowing disorder identified as causing the aspiration, and suggested that the posture strategies were less beneficial in individuals with cricopharyngeal dysfunction or exhibiting multiple swallowing disorders.

A causal relationship between Bordetella pertussis and Bordetella parapertussis infections

Bordetella parapertussis is isolated during the late stages of pertussis outbreaks and occasionally from patients infected with pertussis. The relationship between Bordetella pertussis and B. parapertussis was investigated in mice with monoinfections and mixed infections. Four groups of 10 2-week-old suckling mice were studied: mice born to mice vaccinated against pertussis during pregnancy and unvaccinated controls consequently did and did not receive antipertussis toxin (PT) antibody transcolostrally. The mice were infected transnasally with B. parapertussis strain 422 and 2 identical groups were infected transnasally with B. parapertussis strain 422 and B. pertussis strain 18-323. Bacterial colonization of the lungs and trachea was studied at 1, 2, and 3 weeks after challenge. No persistent colonization by B. parapertussis of the lungs or trachea of monoinfected suckling mice were observed. Persistent colonization by B. parapertussis was observed when suckling mice that received anti-PT antibody transcolostrally were infected with both species. These findings are consistent with the clinical characteristics of B. parapertussis. The results of this study demonstrate that B. pertussis infection facilitates B. parapertussis infection.

Evaluation of pertussis treatment with erythromycin ethylsuccinate and stearate according to age

Although erythromycin estolate has been fully assessed for pertussis treatment, the evaluation of erythromycin ethylsuccinate and stearate, the main erythromycin preparations used in Japan and the US, is inadequate. We evaluated these preparations to establish an appropriate treatment for pertussis according to age. Sixty-six patients with culture-confirmed pertussis were treated with erythromycin administered at a dosage of 40-50 mg/kg/day (maximum, 1.2 g/day). Negative culture was obtained in 39% (15/38) of patients aged 0-2 years within one week and in 71% (27/38) within two weeks, in 78% (7/9) of those aged 3-15 years within one week and in 100% (9/9) within two weeks. All 12 adult patients had a negative culture within one week. The efficacy of erythromycin for the eradication of B. pertussis was significantly lower in children aged 0-2 years than in older children. In conclusion, it is desirable to administer erythromycin for three weeks to children aged 0-2 years, two weeks to those aged 3-15 years and one week to adults.

Efficacy of acellular pertussis vaccine in young infants

A prospective study of a pertussis outbreak in a residential facility was done. Among 19 residents aged < or = 2 years, 10 children were unimmunized and 9 were immunized with acellular pertussis vaccines. Of the 10 unimmunized children, 7 acquired laboratory-confirmed pertussis (four-fold titer rise, positive culture, or both); of these, 6 developed typical symptoms. Eight of the 9 immunized children acquired laboratory-confirmed infections, and 1 of these developed typical symptoms. No difference in infection was noted between the unimmunized and immunized groups (7/10 vs. 8/9, respectively), but a significant difference was observed in the development of symptoms (6/10 vs. 1/9, P < .05). Also, the isolation rate of Bordetella pertussis seemed to differ between the two groups (6/10 vs. 2/9, P = .12). In this population, acellular pertussis vaccine did not prevent infection with B. pertussis but protected most young infants from the onset of clinical symptoms.

Pertussis in adults

A survey was conducted of 89 households in each of which at least one patient with culture-confirmed pertussis had been detected. The source of infection was found to be an adult in 10 (11.2%) of the 89 households, and the rate of secondary attack was 19 (10.3%) of 185. Furthermore, a laboratory study disclosed 17 adults with subclinical pertussis; the subclinical infection rate was 17 (25.0%) of 68. When compared with pertussis in young children, the adult illness was generally less severe and had different clinical features. Adult pertussis showed neither leukocytosis nor lymphocytosis, but it produced anti-pertussis toxin antibody more quickly and higher levels of anti-filamentous hemagglutinin and agglutinin antibodies, and showed stronger growth inhibition of Bordetella pertussis. Although adult pertussis is usually unrecognized because of its different clinical and laboratory features, it is a significant health threat that requires some measures for disease control.

[Pharmacokinetics and the time course of pharmacodynamics of recombinant human erythropoietin (SNB-5001)]

Pharmacokinetics and the time course of pharmacodynamics of recombinant erythropoietin (SNB-5001) were investigated. The plasma concentration of SNB-5001 reached Cmax at 6-7 hr after the subcutaneous injection and gradually decreased. Most of the SNB-5001 in plasma disappeared at 48 hr. Serum erythropoietin activity changed similarly to plasma SNB-5001 concentration. It was indicated that SNB-5001 moves into the plasma and organs having intact bio-activity after its injection. The decrease in serum iron and increase in unsaturated iron binding capacity (UIBC) began at 8 hr after the injection. Both the trough point of serum iron decrease and the peak point of UIBC increase were 24 hr after the injection. Each value recovered to the initial level at 72 hr. Total iron binding capacity did not change. Increase in reticulocytes began at 24 hr and reached the peak at 72-96 hr after the injection of SNB-5001. Reticulocytes count recovered to the initial level at 120 hr. The pharmacodynamics time course after the subcutaneous injection of SNB-5001 was the same as that after the intravenous injection. It was indicated that SNB-5001 reached an effective plasma level at the earlier absorption phase after the subcutaneous injection.

[Molecular epidemiology of Vibrio cholerae O-1 from outbreak and sporadic patients in Nagoya in 1989]

Enterotoxigenic strains of Vibrio cholerae O-1 biotype eltor, isolated from three sporadic cases of cholera in Nagoya in 1989 and an outbreak of cholera in Nagoya in 1989 were analyzed for their similarities. All isolates of V. cholerae O-1 were indistinguishable in bacteriophage types, serovars, biovars and drug resistance patterns. Because the epidemiological investigation based on a primary structure of chromosomal DNA is more reliable, we isolated chromosomal DNA from these isolates and compared electrophoretic patterns of restriction endonuclease-digested DNA fragments. Furthermore, Southern hybridization of the cholera toxin gene was performed. Since no difference among six strains in these sporadic was observed, it was strongly suggested that both the independent cases and the outbreak of cholera were caused by the same strain.

[Simple and efficient method for clinical isolation of Bordetella pertussis]

Commercially available Amies transport medium with charcoal and three isolation media were tested to assess their efficiency in the clinical isolation of B. pertussis. First, the isolation rates of B. pertussis were compared between direct inoculation of nasopharyngeal specimens and inoculation after stored in Amies transport medium for 8 hours or less. The comparative isolation rates were 81% both (35 of 43 specimens from 29 patients) for direct inoculation and transport medium. Second, nasopharyngeal specimens were incubated for 5 days at 35 degrees C on the three media; Bordet-Gengou Medium (BG) with 5 micrograms of CEX per ml, Cyclodextrin Solid Medium (CSM) with 5 micrograms of CEX per ml, and Charcoal Agar with 40 micrograms of CEX per ml. The organism was detected from 44 nasopharyngeal specimens from 20 patients on at least one of the three tested media. The comparative isolation rates were 91% (40 of 44) on BG with 5 micrograms of CEX per ml, 93% (41 of 44) on CSM with 5 micrograms of CEX per ml, and 91% (40 of 44) on CA with 40 micrograms of CEX per ml. Although no differences in the isolation rates were observed among the three media, the appearance of the colonies was earlier by one day on BG than the rest of the two media. The detection of B. pertussis was occasionally easier on CA than the rest of the two because of its higher suppression for nasopharyngeal flora. CSM has its advantage in that it does not need any blood and can be prepared at anytime. Also, the shelf life of these three media proved to be at least one month when stored at 10 degrees C. We conclude that the clinical isolation of B. pertussis was highly successful with the following simple procedure: nasopharyngeal specimens stored in Amies transport medium and inoculated on one of the three media, BG, CSM, or CA, and then incubated for 5 days at 35 degrees C.

[Diphtheria antitoxin levels in Japanese adults (10-20 years after the last vaccination)]

The serum diphtheria antitoxin levels in Japanese adults were investigated and the persistence of diphtheria toxoid effect was evaluated. The subjects consisted of 56 volunteers (20-31 years of age) who had received regular inoculations of diphtheria and pertussis vaccine (I and II or III phases). They had been immunized according to the Vaccination Law (old version) revised in 1958. The length of time after the last inoculation of diphtheria toxoid was speculated to range from 10 to 20 years. Serum diphtheria antitoxin was determined by passive hemagglutination method. Antitoxin level was 0.025 HAU/ml in 1 subject (1.8%), 0.05 in 2 (3.6%), 0.1 in 2 (3.6%), 0.2 in 8 (14.3%), 0.4 in 7 (12.5%), 0.8 in 12 (21.4%), 1.6 in 7 (12.5%) and more than 1.6 in 17 (30.4%). Results indicated that 55 of 56 (98.2%) possessed a higher level than the prophylaxis standard (0.05 HAU/ml). Since the current Vaccination Law prescribes a lower amount and fewer inoculations than the old law, the number of adults possessing prophylactic antitoxin level may decrease in the future. Further investigation of antitoxin level in adults needs to be continued.

[Efficacy of acellular pertussis vaccine]

An outbreak of pertussis occurred in one room of a residential facility where 19 children aged 5 to 36 months were residing. They were prospectively surveyed to estimate the efficacy of acellular pertussis vaccine. Among the 19 residents, 9 were immunized with acellular pertussis vaccine. Among the 19 residents, 9 were immunized with acellular DTP vaccine and 10 were unimmunized. The spread of pertussis was surveyed bacteriologically and serologically for 2 months. Among the 9 immunized, 7 children acquired the laboratory-confirmed pertussis and 1 of the 7 developed the typical symptoms (whooping or paroxysmal coughing attack lasting for 14 days or more). Among the 10 unimmunized, 7 children acquired the laboratory-confirmed pertussis and 6 of the 7 developed the typical symptoms. There was no difference in the rate of secondary infection (7/9:7/10), but there was a significant difference in the rate of development of the typical symptoms (1/7:6/7 p less than 0.05). The point estimate of protective efficacy of the acellular DTP vaccine against typical pertussis was (6/10 - 1/9)/(6/10) x 100 = 81%. It was concluded from these findings that acellular DTP vaccine could not prevent the infection of Bordetella pertussis, but could prevent the development of the typical symptoms.

[Effects of transfer factor on chronic hepatitis B in childhood]

Nine children, 1 to 13 years of age, with HBeAg positive chronic hepatitis B received transfer factor (T.F.) monotherapy for 3 to 17 months, and were monitored by check-ups every six months from serum HBeAg, anti-HBe and GPT. In 12 months, 4 subjects became HBeAg negative and had normal serum GPT. In 22 to 48 months, 6 of the nine subjects had negative HBeAg and normal GPT, 2 had positive HBeAg and high GPT values. The remaining 1 subject who was observed for six months after T.F. therapy remained HBeAg positive with a high GPT values. No side effects were observed. These preliminary observations may indicate beneficial effects of T.F. on the natural course of chronic hepatitis B in childhood, though the ultimate effects awaits longer and well controlled clinical trials.

Heart rate and metabolic responses to participation in golf

Five healthy middle-aged men were asked to perform 18 holes of golf. Heart rate was measured throughout the play, and blood samples were compared before and after play. Oxygen uptake during play was estimated from their heart rate response during a treadmill-walking test. Mean heart rate was 108 (range 92-121) beats/min, which corresponded to 38 (range 35-41) %VO2max. Caloric cost of golf is 4-6 kcal/min and total energy expenditure was estimated more than 960 kcal during 18 holes. Blood glucose decreased and FFA increased following 18 holes of play. Golfing seems to be a suitable sport for middle-aged and elderly persons to enhance energy expenditure.

Efficacy and immunogenicity of acellular pertussis vaccine by manufacturer and patient age

Acellular pertussis vaccines, which have been used in Japan since 1981, vary in antigenic constituents among manufacturers. First, to assess the immunogenicity by manufacturer and patient age, 161 children aged 3 months to 2 years were immunized by acellular pertussis vaccine from one of three Japanese manufacturers, Biken, Takeda, or Kitasato. Anti-pertussis toxin antibody responses for children immunized with Takeda and Kitasato vaccines were comparable with patients with pertussis in the convalescent stage, and anti-pertussis toxin antibody response for Biken vaccine was far higher than those of convalescing patients. Anti-filamentous hemagglutinin antibody responses for the children given the three vaccines were far higher than those of the patients. Weak serotype 1.3 agglutinin responses were observed only in children administered the Takeda vaccine. Comparing these antibody responses among various age groups, the immunogenicity of acellular vaccines in children aged 3 to 6 months was comparable with children aged 2 years. Second, to assess the manufacturer-specific efficacy, 495 households of patients with pertussis were surveyed from 1981 to 1988. The estimated efficacy of the acellular pertussis vaccines in children aged 2 to 8 years was 82%, and there were no major differences in the secondary attack rates among children immunized with acellular pertussis vaccine from each manufacturer, ie, 12.5% (1/8) for Biken, 11.1% (2/18) for Takeda, and 5.9% (1/17) for Kitasato. We conclude from these two studies that similar efficacy was observed in children aged 2 years or older for acellular pertussis vaccines from the three manufacturers, which produced anti-pertussis toxin antibody responses comparable with patients with pertussis and far higher antifilamentous hemagglutinin antibody responses than in the convalescing patients, and that age did not affect the immunogenicity of acellular vaccines.