A delayed response to acute stimulation with human chorionic gonadotropin in scorbutic rats

Since our previous study revealed low basal testosterone (T) levels and a failure in response to an acute stimulation with human chorionic gonadotropin (HCG) despite of a good response to chronic stimulation in scorbutic mutant rats, time course of the response to HCG was studied and plasma LH level was measured in young adult rats deficient in ascorbic acid for 3 weeks. A single subcutaneous injection of HCG (200 IU) elevated T levels only slightly in plasma and not in testicular tissues of scorbutic rats 1 h after the injection when the levels in ascorbutic rats reached a maximum, while it yielded the same response pattern as in ascorbutic rats after 3 h. A pretreatment with HCG to scorbutic rats for 1 or 4 days resulted in the same response of plasma T as in ascorbutic rats. Plasma LH levels in unstimulated scorbutic rats were about 40% of those in ascorbutic rats. These findings indicate that a prolonged deficiency of ascorbic acid decreases plasma LH, and may reduce the sensitivity of testes to LH.

Molecular interactions of alanine-rich and proline-rich regions of cell surface protein antigen c in Streptococcus mutans

INTRODUCTION

Streptococcus mutans has been implicated as a primary causative agent of dental caries in humans, and its cell surface protein antigen c (PAc) is known to be associated with sucrose-independent adhesion to tooth surfaces. PAc is composed of several domains, including an N-terminal signal sequence, an alanine-rich repeat region (A-region), a proline-rich repeat region (P-region), and an anchor region.

METHODS

To investigate the functions of each domain, an A-region-deficient mutant strain of S. mutans was constructed, and recombinant PAc and A- and P-region proteins were also constructed. The interactions of each domain with the recombinant proteins were analyzed using surface plasmon resonance spectroscopy with a biomolecular interaction analyzing system.

RESULTS

The A-region-deficient mutant strain showed the lowest levels of adherence to saliva-coated hydroxyapatite. Furthermore, findings in an immunoblot assay indicated that the A-region protein reacted strongly with proline-rich proteins in saliva, while the recombinant P-region protein interacted more quickly with PAc than the recombinant A-region protein.

CONCLUSION

These results suggest that the A-region has a strong relationship with adhesion to tooth surfaces, while the P-region has a high affinity for PAc.

Age-related maculopathy and sunlight exposure evaluated by objective measurement

Aim:

To study the relationship between age-related maculopathy (ARM) and exposure to sunlight using an objective method.

Methods:

In a case–control study of Japanese men aged ⩾50 years (67 controls without ophthalmic disease and 148 with ARM), those with ARM were separated into groups of early (n = 75) and late (n = 73) ARM. Facial wrinkle length and area of hyperpigmentation, which are considered to be associated with exposure to sun, were measured using imaging with computer-based image analysis. Skin tone was also measured on the upper inner arm, which is not exposed to sun. Early and late ARM association with skin measurements was then evaluated.

Results:

Significantly more facial wrinkling (p = 0.047, odds ratio 3.8; 95% CI 1.01 to 13.97) and less facial hyperpigmentation (p = 0.035, odds ratio 0.3; 95% CI 0.08 to 0.92) was present in late ARM cases. The relationship between skin tone and ARM risk was not statistically significant.

Conclusions:

This objective method showed that lifetime exposure to sunlight is an important factor in the progression of late ARM. An individual’s reaction to sunlight exposure may have a role in ARM progression in addition to total lifetime exposure to sunlight.

Intradural microsurgery and extradural gamma knife surgery for hypoglossal schwannoma: case report and review of the literature

There have been only 26 cases of hypoglossal schwannomas reported to originate intradurally and extend extradurally into the hypoglossal canal. This 31-year-old mother of two children presented with a 5-day history of progressive headache, nausea, vomiting and vertigo. Her neurological exam was significant for nystagmus and left tongue deviation with marked atrophy. An initial head CT revealed extensive left hypoglossal canal erosion with 4th ventricle compression. T1-weighted MR images with contrast revealed a 4x3 cm left cerebellopontine angle non-homogeneously enhancing mass with an intracranial cystic component and prominent extension into the eroded hypoglossal canal. A left lateral suboccipital craniotomy was performed for subtotal microsurgical resection of the intradural posterior fossa mass. A schwannoma was diagnosed after resection and gamma knife surgery (GKS) was performed three months later for the extradural residual tumor without further deficits. This is a rare report of a hypoglossal schwannoma in a young patient who was treated with a multimodality approach in order to minimize risks. A review of the literature and discussion of the respective benefits of microsurgery versus GKS and long-term follow-up issues are presented.

An orthognathic simulation system integrating teeth, jaw and face data using 3D cephalometry

A method for simulating the movement of teeth, jaw and face caused by orthognathic surgery is proposed, characterized by the use of 3D cephalometric data for 3D simulation. Computed tomography data are not required. The teeth and facial data are obtained by a laser scanner and the data for the patient's mandible are reconstructed and integrated according to 3D cephalometry using a projection-matching technique. The mandibular form is simulated by transforming a generic model to match the patient's cephalometric data. This system permits analysis of bone movement at each individual part, while also helping in the choice of optimal osteotomy design considering the influences on facial soft-tissue form.

Leptin facilitates learning and memory performance and enhances hippocampal CA1 long-term potentiation and CaMK II phosphorylation in rats

Leptin, an adipocytokine encoded by an obesity gene and expressed in adipose tissue, affects feeding behavior, thermogenesis, and neuroendocrine status via leptin receptors distributed in the brain, especially in the hypothalamus. Leptin may also modulate the synaptic plasticity and behavioral performance related to learning and memory since: leptin receptors are found in the hippocampus, and both leptin and its receptor share structural and functional similarities with the interleukin-6 family of cytokines that modulate long-term potentiation (LTP) in the hippocampus. We therefore examined the effect of leptin on (1) behavioral performance in emotional and spatial learning tasks, (2) LTP at Schaffer collateral-CA1 synapses, (3) presynaptic and postsynaptic activities in hippocampal CA1 neurons, (4) the intracellular Ca(2+) concentration ([Ca(2+)](i)) in CA1 neurons, and (5) the activity of Ca(2+)/calmodulin protein kinase II (CaMK II) in the hippocampal CA1 tissue that exhibits LTP. Intravenous injection of 5 and/or 50mug/kg, but not of 500mug/kg leptin, facilitated behavioral performance in passive avoidance and Morris water-maze tasks. Bath application of 10(-12)M leptin in slice experiments enhanced LTP and increased the presynaptic transmitter release, whereas 10(-10)M leptin suppressed LTP and reduced the postsynaptic receptor sensitivity to N-methyl-d-aspartic acid. The increase in the [Ca(2+)](i) induced by 10(-10)M leptin was two times greater than that induced by 10(-12)M leptin. In addition, the facilitation (10(-12)M) and suppression (10(-10)M) of LTP by leptin was closely associated with an increase and decrease in Ca(2+)-independent activity of CaMK II. Our results show that leptin not only affects hypothalamic functions (such as feeding, thermogenesis, and neuroendocrine status), but also modulates higher nervous functions, such as the behavioral performance related to learning and memory and hippocampal synaptic plasticity.

A new navigation system based on cephalograms and dental casts for oral and maxillofacial surgery

Intraoperative navigation systems help surgeons to accurately carry out preoperative plans without injuring anatomically important structures. A system is evaluated that uses cephalograms instead of computed tomographic (CT) scans to create images. Three-dimensional (3D) dental casts provide registration between imaging data and the patient. Cephalograms are widely employed in orthognathic and oral and maxillofacial surgery and expose patients to lower doses of radiation than CT. The system uses a dental cast to register the operation field to a pair of frontal and lateral cephalograms. The cast is transformed to 3D data with a laser scanner and a programme that runs on a personal computer. 3D data describing the dental cast, cephalograms and the oral and maxillofacial region of the patient are integrated with specialized software. The optical tracking system for navigation uses charged-coupled-device (CCD) video cameras and light-emitting diodes (LEDs). Two CCD video cameras follow the 3D coordinates of LED assemblies attached to the head, lower jaw and a handpiece. Errors occurring when a dental cast was transformed to 3D data ranged from 0.08 to 0.21 mm. Mean errors were 0.71 mm (0.21-1.09 mm) for the right maxillary central incisor, 0.62 mm (0.04-1.69 mm) for the right maxillary 2nd molar and 1.02 mm (0.23-1.47 mm) for the left maxillary 2nd molar. This surgical navigation system is sufficiently accurate for use in oral and maxillofacial surgery.

Cutaneous infiltration with Waldenström macroglobulinemia

A 59-year-old Japanese man was diagnosed as Waldenström macroglobulinema. With impaired general performance and a 2-year history of pruritic eruptions that were initially confined to the forearms, but later involved the face, limbs, and trunk. A skin biopsy that was performed on the forehead showed infiltration with abnormal cells of the dermis around the central vessels. PCR analysis of the skin biopsy showed immunoglobulin heavy chain rearrangement. As the rearrangement band occurred at the same site as that of the bone marrow aspiration, skin infiltration with abnormal cells was proven.

Electron microscopy and diffraction of radiation-sensitive nanostructured materials

Soft matter research of natural organic and synthetic nanomaterials is an area in nanoscience and technology that has been growing particularly quickly in recent years. The materials under investigation are sensitive to high-energy electrons. Any structure characterization using electron microscopy thus requires special care. First, we illustrated this on naturally grown nanotubes observed by normal and cryogenic scanning electron microscopy. Second, we studied the ordering and orientation of the mesophase in template-grown nanotubes and nanorods containing discotic liquid crystals without and with doping, as desired. For these studies, we mainly used transmission electron diffraction and microscopy at low-dose conditions, high-efficiency image acquisition, and cryoprotection of the structures at liquid helium temperature. Additional analytical information was obtained by electron energy filtering observations.

Glycolipids and phospholipids as natural CD1d-binding NKT cell ligands

Natural killer T (NKT) cells have been shown by a number of studies to play a protective role against cancers, autoimmune diseases and infectious diseases. Several glycolipids and phospholipids derived from mammalian, bacterial, protozoan and plant species have recently been identified as natural ligands (antigens) for NKT cells. Some of these glycolipid/phospholipid ligands have now been crystallized in forms bound to CD1d molecules, and the tertiary structure of these complexes has finally been revealed. This review is intended to list natural NKT cell ligands identified to date, and discuss how their structures relate to their propensity to bind CD1d molecules and, as a consequence, stimulate NKT cells.

Microarray analysis of a reversible model and an irreversible model of anti-Thy-1 nephritis

A single intravenous injection of anti-Thy-1 monoclonal antibody (mAb) 1-22-3 is known to cause reversible mesangial proliferative glomerulonephritis. However, mAb 1-22-3 injection followed by unilateral nephrectomy leads to progressive glomerulosclerosis and tubulointerstitial change with an irreversible course. To identify genes that play an important role in the irreversible progression of renal injury, we used microarray technology to identify differences in gene expression between these models. Rats were intravenously injected with mAb 1-22-3 1 week after unilateral nephrectomy (irreversible model) or a sham operation (reversible model), and rats were killed on days 4, 7, 14, 42, and 56 after the injection. complementary DNA probes prepared from kidney messenger RNAs were hybridized with oligonucleotide microarrays containing 4854 rat genes. The microarray identified 189 differentially expressed genes, having at least a two-fold difference in expression level between the two models, and they were classified into five clusters. One of the clusters consisted of genes whose expression was markedly upregulated in the irreversible model. This cluster included the genes encoding osteopontin, kidney injury molecule-1, and thymosin beta10. Increased expression of thymosin beta10 was localized mainly in macrophages in the fibrotic interstitium, and upregulation of thymosin beta10 expression was also observed in a unilateral ureteral obstruction model. The microarray analysis yielded information on the molecular mechanisms responsible for the difference in disease progression between the reversible and irreversible model of anti-Thy-1 nephritis. Thymosin beta10 may play an important role in the progression of kidney disease.

Immunogenicity and protection of a recombinant human adenovirus serotype 35-based malaria vaccine against Plasmodium yoelii in mice

Given the promise of recombinant adenovirus type 5 (rAd5) as a malaria vaccine carrier in preclinical models, we evaluated the potency of rAd35 coding for Plasmodium yoelii circumsporozoite protein (rAd35PyCS). We chose rAd35 since a survey with serum samples from African subjects demonstrated that human Ad35 has a much lower seroprevalence of 20% and a much lower geometric mean neutralizing antibody titer (GMT) of 48 compared to Ad5 (seroprevalence, 85%; GMT, 1,261) in countries with a high malaria incidence. We also demonstrated that immunization with rAd35PyCS induced a dose-dependent and potent, CS-specific CD8(+) cellular and humoral immune response and conferred significant inhibition (92 to 94%) of liver infection upon high-dose sporozoite challenge. Furthermore, we showed that in mice carrying neutralizing antibody activity against Ad5, mimicking a human situation, CS-specific T- and B-cell responses were significantly dampened after rAd5PyCS vaccination, resulting in loss of inhibition of liver infection upon sporozoite challenge. In contrast, rAd35 vaccine was as potent in naive mice as in Ad5-preimmunized mice. Finally, we showed that heterologous rAd35-rAd5 prime-boost regimens were more potent than rAd35-rAd35 because of induction of anti-Ad35 antibodies after rAd35 priming. The latter data provide a further rationale for developing rAd prime-boost regimens but indicate that priming and boosting Ad vectors must be immunologically distinct and also should be distinct from Ad5. Collectively, the data presented warrant further development of rAd35-based vaccines against human malaria.

Cariogenicity of the Probiotic Bacterium Lactobacillus salivarius in Rats

Probiotic bacteria such as lactobacilli and bifidobacteria are considered to be non-pathogenic and non-toxigenic on the basis of long years of safe usage. However, some species of lactobacilli are thought to be associated with the development of dental caries. The purpose of the present study was to examine the cariogenicity of the probiotic bacterium Lactobacillus salivarius in rats. Rats were divided into six groups, and infected with L. salivarius LS1952R and/or Streptococcus mutans MT8148R. L. salivarius LS1952R became established in the oral cavity of rats and induced significant level of dental caries even when infected for only 5 days from 18 to 22 days of age. In addition, the caries scores of rats superinfected with both Streptococcus mutans MT8148R and L. salivarius LS1952R from 18 days of age were significantly higher than those infected with either L. salivarius LS1952R or S. mutans MT8148R alone. Since strain LS1952R can adhere to saliva-coated hydroxyapatites, it is concluded that L. salivarius strain LS1952R possesses an inherent cariogenic activity following adherence to the tooth surface.

Neuroendocrine differentiation of periodic-acid Schiff and Alcian blue-negative signet-ring cell-like cells and tubular adenocarcinoma cells within a gastric cancer

A case of a Borrmann type 2 advanced gastric cancer with endocrine differentiation is described. Histologically, the cancer was either composed of cells arranged in a tubular pattern or formed solid nests of various sizes. The tubular pattern was composed of a moderately differentiated tubular adenocarcinoma. The histology showed partial carcinoid tumor-like features. Cancer cells inside solid nests had a signet-ring cell-like appearance. Periodic-acid Schiff (PAS) staining was positive in the cytoplasm of a few of the cells found in the tubular pattern and in the mucus in some lumens and on the apical surface of cells in some lumens, but PAS did not stain cancer cells in the solid nests. Neither cancer cells nor mucus in the lumens were stained with alcian blue. All cancer cells were strongly positive for Grimelius silver stain, and most of the cancer cells stained positively for chromogranin A. Electron microscopic examination showed electron dense neuroendocrine granules in the cytoplasm of cancer cells. Cancer cells were stained positively for pancytokeratin, cytokeratin 8/18 and carcinoembryonic antigen. Muc 1 mucin glycoprotein staining was positive along the cell surfaces of cancer cells, but Muc 2, 5AC and 6 stainings were negative, although Muc 3 stained positively in the cytoplasm of a few cancer cells. The present case is a gastric tubular adenocarcinoma with Muc 1-positive, neutral- and acid mucin-negative signet-ring cell-like cells, which is associated with neuroendocrine differentiation.

Intentional replantation of an immature permanent lower incisor because of a refractory peri-apical lesion: case report and 5-year follow-up

We performed an intentional replantation of an immature lower incisor that had a refractory peri-apical lesion. The incisor was extracted and the peri-apical lesion was removed by curettage. The root canal of the tooth was then rapidly irrigated, and filled with a calcium hydroxide and iodoform paste (Vitapex(R)), after which the tooth was fixed with an arch wire splint. Five years later, no clinical or radiographic abnormalities were found, and the root apex was obturated by an apical bridge formation. A team of two dentists is essential to prevent a prolonged operation time, thus eliminating any of the causes of ankylosis. Furthermore, calcium hydroxide and iodoform paste, along with an arch wire splint retained with composite resin, led to good healing of the periodontal tissue after the intentional replantation. Our results indicate that intentional replantation is a useful method for an immature tooth with refractory peri-apical problems.

Experimental transmission of abnormal prion protein (PrPsc) in the small intestinal epithelial cells of neonatal mice

Using an immunohistochemical method, we attempted to detect the transmission of abnormal prion protein (PrPsc) to the enterocytes of the small intestine of neonatal mice by oral exposure with sheep brain affected by scrapie. Five 1-day-old neonatal mice were exposed by oral inoculation to the homogenized brain of a scrapie-affected sheep. In the small intestine of all mice 1 hour after inoculation, immunoreactivity with antinormal prion protein (PrPc) antibody was seen in the cytoplasm of villus enterocytes. This finding suggests transmission of abnormal PrPsc into the cytoplasm of enterocytes. In control mice treated with normal sheep brain, no PrPc signal was seen in enterocytes of the small intestine. Immunopositivity for neurofilament protein and glial fibrillary acidic protein was seen in the cytoplasm of enterocytes of mice inoculated with scrapie and normal sheep brain. This suggests that the enterocytes of neonatal mice can absorb PrPsc and other macromolecular proteins of the sheep brain affected by scrapie and may be more important than previously thought as a pathway for PrPsc transmission in neonatal animals.

Time series analysis of aerobic bacterial flora during Miso fermentation

AIMS

This article reports a microbiological study of aerobic mesophilic bacteria that are present during the fermentation process of Miso.

METHODS AND RESULTS

Aerobic bacteria were enumerated and isolated from Miso during fermentation and divided into nine groups using traditional phenotypic tests. The strains were identified by biochemical analysis and 16S rRNA sequence analysis. They were identified as Bacillus subtilis, B. amyloliquefaciens, Kocuria kristinae, Staphylococcus gallinarum and S. kloosii. All strains were sensitive to the bacteriocins produced by the lactic acid bacteria isolated from Miso.

CONCLUSIONS

The dominant species among the undesirable species throughout the fermentation process were B. subtilis and B. amyloliquefaciens. It is suggested that bacteriocin-producing lactic acid bacteria are effective in the growth prevention of aerobic bacteria in Miso.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study has provided useful information for controlling of bacterial flora during Miso fermentation.

Successful treatment with micafungin of invasive pulmonary aspergillosis in acute myeloid leukemia, with renal failure due to amphotericin B therapy

Invasive aspergillosis is an important factor in the morbidity and mortality of patients suffering from hematologic disorders treated with chemotherapy. Treatment with amphotericin B is often limited because of toxicity, particularly nephrotoxicity. We describe a case of invasive pulmonary Aspergillus fumigatus infection in acute myeloid leukemia with renal failure due to amphotericin B therapy, which responded to treatment with a new antifungal agent, micafungin. Micafungin appears to be an effective and safe therapy for Aspergillus infections with renal failure due to amphotericin B.

Experimental vertical transmission of Borna disease virus in the mouse

We demonstrated the experimental vertical transmission of Borna disease virus (BDV) in pregnant BALB/c mice. Giessen strain He/80 of BDV was used in the present study. Six six-week-old mice were inoculated intraperitoneally with 10(5) 50% tissue culture infective doses (TCID50), and were bred immediately. Four pregnant mice were sacrificed under anaesthesia on the 10th and 14th days after vaginal plug formation. Nine newborns from two maternal mice were sacrificed under anaesthesia on the 7th day after birth. Positive signals with RT-nested PCR techniques for BDV p24-RNAs were seen in the fetuses, placentas and brains of all newborn mice. No immunopositivities for BDV p40 were found in the fetuses or placentas at 10 days' gestation. BDV p40 immunopositivities were found in neurons of the fetal brains and in decidual cells of the placentas at 14 days' gestation. They were also found in neurons of the brains of newborn mice. At 10 days' gestation, no positive signals for BDV p40 sense or antisense riboprobes were seen in the fetal brains or placentas. Positive signals were found in neurons of the fetal brains and decidual cells of the placentas at 14 days' gestation. Positive signals for BDV p40 sense and antisense riboprobes were found in almost all neurons throughout the brains of nine newborn mice. These results suggest that persistent infection with BDV in newborn mice may be induced by vertical transmission during gestation.

Intracerebroventricular administration of endothelin-1 impairs the habituation of rats to a novel environment in conjunction with brain serotonergic activation

The effects of i.c.v. administration of endothelin-1, at a low dose that does not produce abnormal behaviors such as barrel-rolling, on the emotional state of rats exposed to a novel environment were examined. Changes in the emotional state of rats with a novel environment were evaluated in terms of changes in exploratory activity in the hole-board apparatus, i.e., locomotor activity as well as the number and duration of rearing and head-dipping behaviors. Rats treated with i.c.v. saline showed marked exploratory behaviors immediately after exposure to the hole-board apparatus, but these exploratory behaviors decreased rapidly with time. On the other hand, the habituation of rats to a novel environment was prolonged by the i.c.v. administration of endothelin-1 (0.3 and 1 pmol). Furthermore, we also found that i.c.v. administration of endothelin-1 (1 pmol) significantly increased the serotonin (5-hydroxytryptamine) turnover in some brain regions, i.e., the cerebral cortex, hippocampus and midbrain, and the inhibition of brain 5-hydroxytryptamine synthesis by treatment with p-chlorophenylalanine (200 mg/kg/day, s.c.) for 2 days suppressed the behavioral effects of endothelin-1 (1 pmol, i.c.v.). In addition, i.c.v. administration of endothelin-1 (1 pmol) did not affect the spontaneous motor activity of rats. The present study demonstrated that i.c.v. administration of low doses of endothelin-1 impairs the habituation of rats to a novel environment in conjunction with brain 5-hydroxytryptaminergic activation. These results suggest that the central endothelin system may play a significant role in mediating emotionality.

Ground-glass hepatocytes in fibrinogen storage disease in Japanese Black calves

This paper reports the occurrence of large intracytoplasmic inclusions observed in the hepatocytes of six Japanese Black calves showing clinical illness. These inclusions were round to elongated polyhedral in shape, with a consistently homogeneous glassy appearance. Hepatocytes with the inclusions had a ground-glass appearance. The inclusions were negative for the periodic acid-Schiff reaction and methenamine silver stain. Immunohistochemically, they were strongly positive for fibrinogen. Electron microscopy revealed that the inclusions consisted of granular material, showing moderate electron density and bounded by a unit membrane. On the external surface of the unit membrane, there were direct connections to cellular organelles, including the ribosomes and rough-surfaced endoplasmic reticulum. The results showed these inclusions to be entirely consistent with fibrinogen inclusions described in man. Hepatocellular fibrinogen storage disease, as identified in this study, has not previously been described in animals.

Photoreceptor cell differentiation in retinoblastoma demonstrated by a new immunohistochemical marker mucin-like glycoprotein associated with photoreceptor cells (MLGAPC)

AIMS

For further understanding of specific differentiation in retinoblastoma, we studied the expression of newly detected mucin-like glycoprotein associated with photoreceptor cells (MLGAPC), which is specific for photoreceptor cells of retina and analogous to interphotoreceptor matrix proteoglycan-1 (IMPG1).

METHODS AND RESULTS

Surgically enucleated retinoblastomas (n=21; undifferentiated type, n=15, differentiated type, n=6) were immunohistochemically studied with a polyclonal antibody against MLGAPC, and 17/21 cases (81%) showed positive staining of tumour cells. We classified various staining patterns and structures into four groups: type 1 showing a granular intracellular scattered staining pattern with round small cells; type 2 showing a reticular staining pattern between spindle-shaped tumour cells; type 3 showing radiating staining from the centre of Homer-Wright rosettes; type 4 showing ring-shaped, radiating and granular staining associated with Flexner-Wintersteiner rosettes. Eleven of 15 undifferentiated retinoblastomas (73%) showed type 1 or 2, and all the six differentiated cases showed type 3 or 4. Image analysis of immunostaining revealed an increase in MLGAPC-positive area from 0.48% in undifferentiated cases to 1.60% in differentiated cases, and a negative correlation was shown between mitotic frequency and MLGAPC-positive area.

CONCLUSIONS

This study proved MLGAPC as a valuable marker of retinoblastoma, and that photoreceptor differentiation takes place even in 'undifferentiated' retinoblastoma.

An estimation of economic effects of tele-home-care: hospital cost-savings of the elderly

Tele-home-care (or tele-medicine) is being implemented by the application of multimedia such as CATV and ISDN. In this paper, by focusing on the so-called "social hospitalization of the aged," we carry out an estimation of the extent to which tele-home-care based on multimedia can help in saving the cost of hospitalization of the aged in the future. Estimation consists of the following two parts. First, we estimate the trends of the aged population and their hospital expenses using the regression analysis. Second, we assume that new technology such as multimedia and new medical instruments develop according to a logistic curve. Thus, we estimate the rate of diffusion of CATV and ISDN by logistic curves. Then, by multiplying this number by hospital costs per elderly patient as estimated previously, we have been able to calculate the extent to which hospitalization costs can be saved in the entire economy. Our results indicated that in the year 2050, US$257.3 billion, or nearly 7.4% of total hospitalization costs of the aged could be saved by tele-home-care.

Widespread distribution of the bacteriocin-producing lactic acid cocci in Miso-paste products

AIMS

A survey was conducted on the ecological distribution of bacteriocin-producing lactic acid bacteria in Miso-pastes, a typical fermented food in Japan. METHODS AND RESULTS Nine Miso-pastes were sampled for isolation of bacteriocin-producers. Almost all isolated enterococcal strains produced bacteriocins but no isolated tetragenococci did so. The bacteriocin-producing isolates were divided into nine groups by phenotypic tests. As the phenotypic characters were highly diverse, these strains could not be identified to species level on the basis of their phenotypes. The nine representative strains from each group were identified by 16S rRNA analysis. These bacteriocin-producers with one exception (Lactococcus sp.) were identified as strains of the Enterococcus faecium 'species group'. The bacteriocins of the nine strains were classified into five types according to their antibacterial spectral patterns and their SDS-PAGE profiles. The bacteriocins inhibited undesirable bacteria in Miso-pastes, such as Bacillus subtilis, but did not inhibit the useful Tetragenococcus halophila.

CONCLUSIONS

The bacteriocin-producing lactic acid cocci were widespread at high frequencies in Miso-pastes. They were considered to play an important role in preventing the growth of undesirable bacteria.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study suggests that bacteriocin-producers act effectively as safe biopreservatives and may contribute to the biopreservation in Miso-pastes.

Peptide-based subunit vaccines against pre-erythrocytic stages of malaria parasites

Malaria currently ranks among the most prevalent infections in tropical and sub-tropical areas throughout the world with relatively high morbidity and mortality particularly in young children. The widespread occurrence and the increased incidence of malaria in many countries, caused by drug-resistant parasites (Plasmodium falciparum and P. vivax) and insecticide-resistant vectors (Anopheles mosquitoes), indicate the need to develop new methods of controlling this disease. Experimental vaccination with radiation-attenuated sporozoites can protect animals and humans against the disease, demonstrating the feasibility of developing an effective malaria vaccine. However, vaccines based on radiation-attenuated sporozoites are not feasible for large scale application due to lack of in vitro culture system. Therefore, the development of peptide-based subunit vaccines has been undertaken as an alternative approach. Synthetic peptides containing defined B- and T-cell epitopes of different antigens expressed in sporozoites and/or liver stages have been used as subunit vaccines in experimental animal models. They have been shown to be highly immunogenic and capable of inducing protective immunity mediated by antibodies, as well as CD4+ and CD8+ T-cells.

Human babesiosis in Japan: epizootiologic survey of rodent reservoir and isolation of new type of Babesia microti-like parasite

We have carried out epizootiologic surveys at various sites in Japan to investigate wild animals that serve as reservoirs for the agents of human babesiosis in the country. Small mammals comprising six species, Apodemus speciosus, Apodemus argenteus, Clethrionomys rufocanus, Eothenomys smithii, Crocidura dsinezumi, and Sorex unguiculatus, were trapped at various places, including Hokkaido, Chiba, Shiga, Hyogo, Shimane, and Tokushima Prefectures. Animals harboring Babesia microti-like parasites were detected in all six prefectures. Inoculation of their blood samples into hamsters gave rise to a total of 20 parasite isolates; 19 were from A. speciosus, and the other 1 was from C. rufocanus. Sequencing of the parasite small-subunit rRNA gene (rDNA) sequence revealed that 2 of the 20 isolates were classified as Kobe type because their rDNAs were identical to that of the Kobe strain (the strain from the Japanese index case). The other 18 isolates were classified as a new type, designated the Hobetsu type, because they all shared an identical rDNA sequence which differed significantly from both that of Kobe-type isolates and that of northeastern United States B. microti (U.S. type). The parasites with Kobe-, Hobetsu- and U.S.-type rDNAs were phylogenetically closely related to each other but clearly different from each other antigenically. The isolates from rodents were demonstrated to be infective for human erythrocytes by inoculation into SCID mice whose erythrocytes had been replaced with human erythrocytes. The results suggest that a new type of B. microti-like parasite, namely, the Hobetsu type, is the major one which is prevalent among Japanese wild rodents, that A. speciosus serves as a major reservoir for both Kobe- and Hobetsu-type B. microti-like parasites, and that C. rufocanus may also be an additional reservoir on Hokkaido Island.

Purification and identification of the essential ionizable groups of honeybee, Apis mellifera L., trehalase

Trehalase (EC 3.2.1.28) of the bound type was purified as an electrophoretically homogeneous protein from adult honeybees by fractionation with ammonium sulfate, hydrophobic chromatography, and DEAE-Sepharose CL-6B, CM-Sepharose CL-6B, butyl-Toyopearl 650M, and p-aminophenyl beta-glucoside Sepharose 4B column chromatographies. The enzyme preparation was confirmed to be a monomeric protein containing 3.1% carbohydrate. The molecular weight was estimated to be approximately 69,000, and the optimum pH was 6.7. The Michaelis constant (Km) was 0.66 mM, and the molecular activity (k0) was 86.2 s(-1). The enzyme was an "inverting" type which produced beta-glucose from alpha, alpha-trehalose. Dependence of the V and Km values on pH gave values for the ionization constants, pKe1 and pKe2, of essential ionizable groups 1 and 2 of the free enzyme of 5.3 and 8.5, respectively. When the dielectric constant of the reaction mixture was decreased, pKe1, and pKe2 were shifted to higher values of + 0.2 and + 0.5 pH unit, respectively. The ionization heat (deltaH) of ionizable group 1 was estimated to be + 1.8 kcal/mol, and the deltaH value of group 2 was + 1.5 kcal/mol. These findings strongly support the notion that the essential ionizable groups of honeybee trehalase are two kinds of carboxyl groups, one being a dissociated type (-COO(-), ionizable group 1) and the other a protonated type (-COOH, ionizable group 2), although the pKe2 value is high.

Cyst fluid levels of carcinoembryonic antigen, carbohydrate antigen 19-9, squamous cell carcinoma antigen, and amylase in thyroglossal duct and branchial cleft cysts

Cyst fluid was aspirated from five thyroglossal duct cysts (TDCs) and four branchial cleft cysts (BCCs). The cyst fluid levels of carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9, squamous cell carcinoma antigen (SCC), and amylase were measured and compared between the two types of cyst. The enzyme immunoassay technique was used for CEA and CA19-9, while SCC and amylase levels were measured by the immunoradiometric assay and nitrophenol method, respectively. Immunostaining for CEA, CA19-9, and amylase was also performed. The serum levels of these markers in both groups of patients were within the normal ranges. In contrast, their cyst fluid levels were extremely high. There was no significant difference in the cyst fluid levels of CEA and SCC between the two types of cyst; however, the cyst fluid from the TDCs showed significantly higher levels of CA19-9 and significantly lower levels of amylase compared with that from the BCCs. Immunostaining revealed expression of CA 19-9 in nearly half the columnar epithelial cells in the TDCs, but not in the squamous epithelial cells in the BCCs. CEA and amylase were not found in the epithelial cells of either type of cyst. These findings seem to reflect the difference in etiology between TDCs and BCCs.

Transforming growth factor (beta1) in testes of aged and diabetic rats: correlation with testicular function

This study was conducted to evaluate the expression of transforming growth factor-beta1 (TGF-beta1) in testis with aging and progress of diabetes mellitus (DM) and correlated this with testicular function. Zucker diabetic fatty rats (15, 40, and 75 weeks old) were used as models for non-insulin-dependent DM. The controls were age-matched nondiabetic Zucker fatty rats. Serum testosterone levels and daily sperm production were evaluated. Testicular tissue was immunostained with anti-TGF-beta1. Labeled cells were assessed and the staining intensity was estimated. The 15-week control and diabetic animals showed the lowest levels of staining intensity but this started to increase significantly in the older animals of both categories. However, the diabetic animals had significantly deeper intensities relative to controls at the different age groups. These changes in TGF-beta1 expression were negatively correlated with both testosterone and sperm production. Therefore, aging and DM enhanced the expression of TGF-beta1 in testis, and this was parallel with progress of both conditions, although DM seems to be predominant. These alterations in TGF-beta1 expression may be related to changes in testicular function associated with both conditions.

[Inhibitors of absorption as anti-obesity drugs]

There are two types of anti-obesity agents which are classified as inhibitors of absorption: inhibitors of lipid and carbohydrate absorption. Inhibitors of lipid absorption consist of lipase inhibitor (orlistat, Nomma Herb's extract (CT-II) and fat substitute (olestra, sucrose polyester). Orlistat is now available as an anti-obesity drug in the USA and Europe. CT-II may be useful as a functional diet. Application of fat substitute is still limited in snack food. As for inhibitors of carbohydrate absorption, alpha-glucosidase inhibitors are now available as anti-diabetic drugs. To develop these agents for anti-obesity drug, solution of adverse effects on the gastrointestinal tract are necessary.

Detection of malaria liver-stages in mice infected through the bite of a single Anopheles mosquito using a highly sensitive real-time PCR

We describe a highly sensitive real-time PCR to detect and measure the development of the liver-stages of malaria parasites in mice infected with sporozoites ranging in number from 25 to more than 164,000, using the same reaction conditions. Furthermore, this assay detects and measures parasite loads in the livers of mice exposed to the bite of a single malaria-infected Anopheles mosquito. This unique method should greatly facilitate studies aimed at evaluating very precisely the efficacy of anti-malarial experimental drug treatments and vaccination regimens in conditions of infection resembling those found in the field.

Complete, long-lasting protection against malaria of mice primed and boosted with two distinct viral vectors expressing the same plasmodial antigen

We report that complete protection against malaria and total inhibition of liver stage development and parasitemia was obtained in 100% of BALB/c mice primed with a replication-defective recombinant adenovirus expressing the circumsporozoite (CS) protein of Plasmodium yoelii (AdPyCS), followed by a booster with an attenuated recombinant vaccinia virus, expressing the same malaria antigen, VacPyCS. We found increased levels of activated CS-specific CD8(+) and CD4(+) T cells, higher anti-sporozoite antibody titers, and greater protection in these mice, when the time between priming and boosting with these two viral vectors was extended from 2 to 8 or more weeks. Most importantly, by using this immunization regimen, the protection of the immunized mice was found to be long-lasting, namely complete resistance to infection of all animals 3 1/2 months after priming. These results indicate that immunization with AdPyCS generates highly effective memory T and B cells that can be recalled long after priming by boosting with VacPyCS.

Castration induces apoptosis in the male accessory sex organs of Fas-deficient lpr and Fas ligand-deficient gld mutant mice

The role of the Fas ligand-Fas system in castration-induced apoptosis in the epithelia of the ventral prostate (VP), seminal vesicle (SV), coagulating gland (CG) and epididymis (Ep) was investigated using lpr/lpr, and gld/gld mutant mice which are deficient in Fas and Fas ligand, respectively. The degree of apoptosis in the epithelium was quantitatively estimated by an apoptotic index (a percentage of apoptotic cells). The weights (mg/10 g body weight) of the VP, SV, CG and Ep of lpr/lpr and gld/gld mice were similar to those of normal +/+ mice and castration decreased the weights of the VP, SV, CG and Ep in these three kinds of mice to similar levels. Castration also increased the apoptotic indices in these organs reaching maximum on days 2-6 after castration. There was no significant difference in the apoptotic index of these organs among +/+, lpr/lpr and gld/gld mice on days 0-8 after castration. Agarose gel electrophoresis of DNAs extracted from the VP, SV, CG and Ep of +/+, lpr/lpr and gld/gld mice on day 4 after castration showed a ladder pattern. The present results suggest that the Fas ligand-Fas system plays little role in castration-induced apoptosis in the mouse male accessory sex organs such as the VP, SV, CG and Ep.

Induction of neurite outgrowth in PC12 cells by alpha -phenyl-N-tert-butylnitron through activation of protein kinase C and the Ras-extracellular signal-regulated kinase pathway

The spin trap alpha-phenyl-N-tert-butylnitron (PBN) is widely used for studies of the biological effects of free radicals. We previously reported the protective effects of PBN against ischemia-reperfusion injury in gerbil hippocampus by its activation of extracellular signal-regulated kinase (ERK) and suppression of both stress-activated protein kinase and p38 mitogen-activated protein kinase. In the present study, we found that PBN induced neurite outgrowth accompanied by ERK activation in PC12 cells in a dose-dependent manner. The induction of neurite outgrowth was inhibited significantly not only by transient transfection of PC12 cells with dominant negative Ras, but also by treatment with mitogen-activated protein kinase/ERK kinase inhibitor PD98059. The activation of receptor tyrosine kinase TrkA was not involved in PBN-induced neurite outgrowth. A protein kinase C (PKC) inhibitor, GF109203X, was found to inhibit neurite outgrowth. The activation of PKCepsilon was observed after PBN stimulation. PBN-induced neurite outgrowth and ERK activation were counteracted by the thiol-based antioxidant N-acetylcysteine. From these results, it was concluded that PBN induced neurite outgrowth in PC12 cells through activation of the Ras-ERK pathway and PKC.

Human babesiosis in Japan: isolation of Babesia microti-like parasites from an asymptomatic transfusion donor and from a rodent from an area where babesiosis is endemic

To determine the source of infection for the Japanese index case of human babesiosis, we analyzed blood samples from an asymptomatic individual whose blood had been transfused into the patient. In addition, we surveyed rodents collected from near the donor's residence. Examination by microscopy and PCR failed to detect the parasite in the donor's blood obtained 8 months after the donation of the blood that was transfused. However, we were able to isolate Babesia parasites by inoculating the blood sample into SCID mice whose circulating red blood cells (RBCs) had been replaced with human RBCs. A Babesia parasite capable of propagating in human RBCs was also isolated from a field mouse (Apodemus speciosus) captured near the donor's residential area. Follow-up surveys over a 1-year period revealed that the donor continued to be asymptomatic but had consistently high immunoglobulin G (IgG) titers in serum and low levels of parasitemia which were microscopically undetectable yet which were repeatedly demonstrable by inoculation into animals. The index case patient's sera contained high titers of IgM and, subsequently, rising titers of IgG antibodies, both of which gradually diminished with the disappearance of the parasitemia. Analysis of the parasite's rRNA gene (rDNA) sequence and immunodominant antigens revealed the similarity between donor and patient isolates. The rodent isolate also had an rDNA sequence that was identical to that of the human isolates but that differed slightly from that of the human isolates by Western blot analysis. We conclude that the index case patient acquired infection by transfusion from a donor who became infected in Japan, that parasitemia in an asymptomatic carrier can persist for more than a year, and that A. speciosus serves as a reservoir of an agent of human babesiosis in Japan.

Purification and substrate specificity of honeybee, Apis mellifera L., alpha-glucosidase III

Alpha-glucosidase III, which was different in substrate specificity from honeybee alpha-glucosidases I and II, was purified as an electrophoretically homogeneous protein from honeybees, by salting-out chromatography, DEAE-cellulose, DEAE-Sepharose CL-6B, Bio-Gel P-150, and CM-Toyopearl 650M column chromatographies. The enzyme preparation was confirmed to be a monomeric protein and a glycoprotein containing about 7.4% of carbohydrate. The molecular weight was estimated to approximately 68,000, and the optimum pH was 5.5. The substrate specificity of alpha-glucosidase III was kinetically investigated. The enzyme did not show unusual kinetics, such as the allosteric behaviors observed in alpha-glucosidases I and II, which are monomeric proteins. The enzyme was characterized by the ability to rapidly hydrolyze sucrose, phenyl alpha-glucoside, maltose, and maltotriose, and by extremely high Km for substrates, compared with those of alpha-glucosidases I and II. Especially, maltotriose was hydrolyzed over 3 times as rapidly as maltose. However, maltooligosaccharides of four or more in the degree of polymerization were slowly degraded. The relative rates of the k0 values for maltose, sucrose, p-nitrophenyl alpha-glucoside and maltotriose were estimated to be 100, 527, 281 and 364, and the Km values for these substrates, 11, 30, 13, and 10 mM, respectively. The subsite affinities (Ai's) in the active site were tentatively evaluated from the rate parameters for maltooligosaccharides. In this enzyme, it was peculiar that the Ai value at subsite 3 was larger than that of subsite 1.

In vitro antibody response to the tetrapeptide repeats of Plasmodium falciparum circumsporozoite protein by splenocytes from mice infected with P. yoelii yoelii

The antibody response to the recombinant protein, R32tet32, which contained the repetitive sequence (NANP)n of Plasmodium falciparum CSP was determined in C57BL/6 mice during the course of nonlethal infection with Plasmodium yoelii 17X. Marked suppression of the IgG antibody response to R32tet32 occurred when mice were immunized at peak parasitemia (on day 16). In vitro antibody responses of spleen cells from acutely infected mice to R32tet32 were similarly suppressed. Stimulation of normal spleen cells cultured for 5 days with 100 ng/ml of R32tet32 gave an optimal IgG antibody response, but spleen cells from infected mice obtained at peak parasitemia failed to respond to a broad range of antigen concentrations. Cocultivation studies employing enriched lymphocyte populations from infected and uninfected C57BL/6 mice indicated that both T and B cells from infected mice were defective in their response to R32tet32. The response to the repetitive region was restored by the addition of recombinant mouse interleukin-2 (IL-2) at a dose of 50 U/ml to cultures of spleen cells from infected mice.

Molecular analysis of Salmonella Enteritidis isolates resistance to ampicillin and streptomycin from three outbreaks of food poisoning in Shiga prefecture

In 1998 and 1999, there were three outbreaks caused by Salmonella Enteritidis in Shiga Prefecture. One outbreak was suspected to be a diffuse outbreak, caused by frozen cream puffs that had been sold in chain stores throughout Shiga Prefecture between the beginning of September and the beginning of October, 1998. The other outbreaks occurred in May and in August, 1999. All isolates of the three outbreaks showed an identical lysis pattern against the typing phage, though this pattern did not conform to the current scheme, so-called RDNC. In addition all isolates were resistant to ampicillin and streptomycin. However, the patterns of pulsed-field gel electrophoresis strongly indicated that the three outbreaks were actually independent.