Increased susceptibility to Toxoplasma gondii infection in SAG-1 transgenic mice

SAG-1, one of the major surface proteins of Toxoplasma gondii, has been reported to play an important role in immune and pathogenic mechanisms of the parasites but its exact function is still unclear. We investigated the time courses of T. gondii infection in B6C3F1 transgenic mice carrying the SAG-1 gene. SAG-1 transgenic mice were infected intraperitoneally with a high virulent RH strain or a low virulent Beverley strain of T. gondii. When infected with RH strain tachyzoites, no significant differences in time courses of survivals between SAG-1 transgenic and wild-type mice were observed. Both groups succumbed to an acute infection within 8 days after infection. However, a lower survival rate (20%) was observed in SAG-1 transgenic mice than in wild-type (80%), when infected with Beverley strain cysts. This result indicates that SAG-1 transgenic mice are more susceptible to T. gondii infection as compared with their wild-type counterpart. ELISA using recombinant SAG-1 protein indicates that SAG-1 transgenic mice do not produce antibodies to the SAG-1 molecule. These findings may provide a critical tool for analysing the molecular mechanisms of pathogenesis and host immune responses during toxoplasmosis.

Interleukin-12, interferon-gamma and interleukin-4 gene expression in cats infected with Toxoplasma gondii

Interleukin-12, Interferon-gamma and Interleukin-4 mRNA levels in cells of the spleen and mesenteric lymph nodes of cats following primary and secondary infection with Toxoplasma gondii were examined by a semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) method. Expression of Interleukin-12p40 mRNA and Interferon-gamma mRNA was observed after primary and secondary oral infection with Toxoplasma gondii. In contrast, no expression of IL-4 mRNA in the spleen and little expression in the mesenteric lymph nodes were observed after primary infection when the cats shed oocysts, however, the expression of IL-4 mRNA observed in the cats after secondary inoculation.

Both stump area and volume of distal sensory nerve segments influence the regeneration of sensory axons in rats

We examined the influence of both stump area and volume of a distal sensory nerve segment on neurotropic induction of regenerating sensory axons in a rat saphenous nerve model. In group 1 (n = 10) the proximal stump of the severed saphenous nerve was inserted into the proximal channel, and a 2 cm free nerve segment and a double-barrelled 1 cm free nerve segment were inserted into the distal two channels of a silicone Y-chamber. In group 2 (n = 10), 2 cm and 1 cm free nerve segments were inserted into the distal two channels of a Y-chamber. The gap between the stumps was set at 4 mm. After six weeks, we counted and compared the number of regenerated myelinated sensory axons in the distal two channels. Significantly more axons regenerated in the wider stump area channel of group 1 and in the larger volume channel of group 2 than in the opposite channel in either group (p < 0.05 in each case).

Lack of topographical specificity in peripheral nerve regeneration in rats

In a previous study we found that sensory regeneration was neurotropically selective regardless of the end organ, but motor regeneration was not, which made us doubt the existence of topographic specificity. The purpose of the present study was to confirm the existence of topographic specificity in rats. The proximal stump of either the peroneal or tibial nerve was inserted into the proximal limb of a silicone Y-chamber. Both distal stumps of peroneal and tibial nerve were inserted into the distal limbs. The gap between the stumps was set at either 4 mm (n = 8, on each subgroup) or 8 mm (n = 8, on each subgroup). Six weeks later the number of regenerated axons in the distal two limbs were counted and compared. The number of regenerated axons towards the distal tibial nerve side was significantly larger in every model. Regenerated axons from the proximal peroneal stump did not preferentially choose the distal peroneal stump. The existence of topographic specificity is unlikely.

Flexor tendon repair in a rabbit model using a "core" of extensor retinaculum with synovial membrane. An experimental study

In this histological and biomechanical study in two groups of rabbits, a piece of the extensor retinaculum with its synovial membrane was inserted as a biological "core" into a hole at the centre of both stumps of a severed tendon, which was repaired with interrupted sutures. In the other group, the tendon was sutured without a "core". In the "core" group, proliferation and migration of fibroblasts from both tendon surfaces and the "core" surface toward the deep layer of the suture site was seen 2 weeks after operation. New collagen fibres, aligned parallel to the long axis of the tendon, could also be seen 4 weeks after operation, and healing was more advanced than in the coreless model. The maximum force to produce a gap in the "core" tendon was 82% greater than in the coreless tendon 4 weeks after operation.

Experimental study of two new flexor tendon suture techniques for postoperative early active flexion exercises

We used a rabbit model to test the postoperative mechanical strengths of two new tendon suture techniques. These were compared with the conventional modified Kessler and double looped suture techniques. For each technique, maximum load until 3 mm gap, load at 1 mm gap and ultimate load were measured at the time of operation and at weeks 1 and 3 after operation. Maximum load until 3 mm gap and load at 1 mm gap were significantly higher in the new techniques than in the conventional techniques at the time of operation and at 1 week; there was no statistical difference between the four techniques at 3 weeks. No technique resulted in a decrease in maximum load until 3 mm gap, load at 1 mm gap and ultimate load at 1 week. The new techniques reported here have the potential to withstand early active flexion exercises.

Substrate specificity of thermostable farnesyl diphosphate synthase with alkyl group homologs of isopentenyl diphosphate

3-Alkyl group homologs of isopentenyl diphosphate were examined for the reactivity as substrates of the thermostable farnesyl diphosphate (FPP) synthase of Bacillus stearothermophilus. Even 3-n-propyl- and 3-n-butyl-but-3-enyl diphosphates, which are hardly acceptable by animal FPP synthases, are accepted by this bacterial enzyme as substrates to react with dimethylallyl- and geranyl diphosphates, yielding 7-methyl-3-n-propylocta-2,6-dienyl- and 7,11-dimethyl-3-n-propyldodeca-2,6,10-trienyl diphosphate, respectively.

Two subunits of heptaprenyl diphosphate synthase of Bacillus subtilis form a catalytically active complex

Heptaprenyl diphosphate synthase of Bacillus subtilis, which participates in the biosynthesis of the side chain of menaquinone-7, is composed of two dissociable subunits, component I and component II, which are encoded by two cistrons in a novel gene cluster of gerC operon [Zhang, Y.-W., et al. (1997) J. Bacteriol. 179, 1417-1419]. This enzyme essentially requires the coexistence of both subunits for its catalysis. Expression vector systems for the two structural genes, gerC1 and gerC3, were constructed separately, and the two components were overproduced in Escherichia coli cells. After purification, their dynamic interactions in forming a catalytically active complex were investigated by gel filtration and immunoblotting analyses. When a mixture of the two components that had been preincubated in the presence of Mg2+ and farnesyl diphosphate was subjected to Superdex 200 gel filtration, a significant elution peak appeared in a region earlier than those observed when they were chromatographed individually. This fraction contained both components I and II, and it corresponded to a molecular mass that is in accord with the sum of the values of the two components. Cross-linking studies indicate that the two essential subunits, farnesyl diphosphate, and Mg2+ form a ternary complex which seems to represent a catalytically active state of the heptaprenyl diphosphate synthase. On the other hand, no complex was formed in the presence of isopentenyl diphosphate or inorganic pyrophosphate and Mg2+. A photoaffinity analogue of farnesyl diphosphate was shown to preferentially label the component I protein, suggesting that component I possesses a specific affinity for the allylic substrate. Furthermore, the photoaffinity labeling of component I significantly increased in the presence of component II. The mechanism of catalysis of this unique heteromeric enzyme is understood by assuming that association and dissociation of the two subunits facilitate turnover of catalysis for the synthesis of the amphipathic product from soluble substrates.

Transcriptional analysis of Marek's disease virus (MDV) genes in MDV-transformed lymphoblastoid cell lines without MDV-activated cells

Spontaneously activated MDV is rarely included in MDV-transformed cells, while it may influence the results of transcriptional analysis. A population consisting of 10(3) MDV-transformed cells probably did not include spontaneously activated MDV, since the estimated frequency of MDV-transformed cells including activated MDV was below 0.01% according to limiting-dilution polymerase chain reaction (PCR) and the presence of the major early antigen pp38 in 6 transformed cell lines. Reverse transcriptase-PCR (RT-PCR) products corresponding to ICP27, pol, TK, US3, A41, gA, gB and UL50 genes were undetectable in 10(3) cells by Southern hybridization of the RT-PCR products. Transcripts of the VP16 and SORF2 genes were detected in the 10(3) cells of MSB-1, and the pp14 gene transcript was found in 10(3) cells of RPL-1 but not in 10(3) cells of HPRS-1, MOGA-2, MSB-1 or MTB-1. A transcript corresponding to the ICP4 sequence was detected as a 0.7 kbp RT-PCR product in 10(3) cells of these MDV cell lines but not in the retrovirus-transformed 1104B1 cell line. The transcript corresponding to the 0.7 kbp RT-PCR product suggested a splice by its size and sequence. Thus, transcriptional analysis of 10(3) MDV-transformed cells revealed that the transcript corresponding to the ICP4 sequence was a common transcript in latently infected MDV-transformed cells, while most of the genes did not transcribe in these cells.

[Combination chemotherapy with cis-platinum and ifosfamide for hormone unresponsive prostate cancer]

PURPOSE

There is no effective therapy against hormone refractory prostate cancer. This led us to evaluate the effectiveness and toxicity of cis-platinum (CDDP) and ifosfamide (IFM) combination chemotherapy in the patients with hormone-unresponsive carcinoma of the prostate.

METHODS

Patients with hormone-unresponsive prostate cancer were scheduled to receive CDDP 70 mg/m2 intravenously on day 1 and IFM 1.2 g/m2/day intravenously on day 1 through day 5 of 28-day cycle.

RESULTS

Twenty seven patients with hormone unresponsive prostate cancer were enrolled onto this trial. Of these patients, seven (26%) demonstrated a partial objective response (PR), and ten (37%) a stable disease (ST). The response duration of PR cases lasted from 6 to 49 months with a median of 16 months and the response duration of PR + ST cases lasted from 3 to 36 months with a median of 10 months. Subjective improvement was obtained in 11 patients (41%). Survival duration of all cases were 4 to 89 months with a median of 23 months and probabilities of survival at 3 years and 5 years were 36% and 24%, respectively. The toxicity of this treatment was mostly mild to moderate, anemia (96%), leukocytopenia (89%), anorexia (81%), alopecia (67%), thrombocytopenia (44%), hematuria (38%), renal dysfunction (19%) and liver dysfunction (7%) were noticed. Severe toxicity was observed in two cases, one acute renal failure and one endotoxin shock.

CONCLUSION

We conclude that CDDP and IFM combination chemotherapy was active regimen for hormone unresponsive prostate cancer.

Monoclonal antibody against Babesia equi: characterization and potential application of antigen for serodiagnosis

Monoclonal antibody (MAb) BEG3 was produced against Babesia equi parasites to define a species-specific antigen for diagnostic use. The MAb reacted with single, paired, and Maltese cross forms of B. equi, and no reaction was observed with this MAb on acetone-fixed Babesia caballi, Babesia ovata, or Babesia microti parasites in the indirect immunofluorescent antibody test. Confocal laser and immunoelectron microscopic studies showed that the antigen which was recognized by this MAb was located on the surface of B. equi parasites. This MAb recognized a 19-kDa protein of B. equi antigen and did not react with B. caballi antigen or normal horse erythrocytes in immunoblot analysis. This MAb also significantly inhibited the in vitro growth of the B. equi parasite. Preliminary studies using partially purified antigen, which was separated by high-pressure liquid chromatography and recognized by the MAb, suggested that it is a suitable antigen for enzyme-linked immunosorbent assay detection of anti-B. equi antibodies in naturally infected horse sera.

Phylogenetic evidence for the existence of novel thermophilic bacteria in hot spring sulfur-turf microbial mats in Japan

So-called sulfur-turf microbial mats, which are macroscopic white filaments or bundles consisting of large sausage-shaped bacteria and elemental sulfur particles, occur in sulfide-containing hot springs in Japan. However, no thermophiles from sulfur-turf mats have yet been isolated as cultivable strains. This study was undertaken to determine the phylogenetic positions of the sausage-shaped bacteria in sulfur-turf mats by direct cloning and sequencing of 16S rRNA genes amplified from the bulk DNAs of the mats. Common clones with 16S rDNA sequences with similarity levels of 94.8 to 99% were isolated from sulfur-turf mat samples from two geographically remote hot springs. Phylogenetic analysis showed that the phylotypes of the common clones formed a major cluster with members of the Aquifex-Hydrogenobacter complex, which represents the most deeply branching lineage of the domain bacteria. Furthermore, the bacteria of the sulfur-turf mat phylotypes formed a clade distinguishable from that of other members of the Aquifex-Hydrogenobacter complex at the order or subclass level. In situ hybridization with clone-specific probes for 16S rRNA revealed that the common phylotype of sulfur-turf mat bacteria is that of the predominant sausage-shaped bacteria.

Toward a virtual-labo-system for metabolic engineering: development of biochemical engineering system analyzing tool-kit (BEST-KIT)

BEST-KIT is an efficient and user-friendly "biochemical engineering system analyzing tool-kit" integrated the following key modules: 1) mathematical modeling and editing of reaction-scheme, 2) automatic derivation of differential equations, 3) numerical calculation, 4) nonlinear optimization, 5) visualization, 6) retrieve the information on reaction mechanism and kinetic parameters from data-base of metabolic pathways. The users of this simulator are assumed to be unfamiliar with computer technology and with computer programming. The integrated interface (UNIX version) is based on Xlib, XToolkit and OSF/Motif Widget.

Blood flow in mobilized nerves: results in a rabbit sciatic nerve model

The purpose of this study was to evaluate the immediate effect on capillary blood flow of surgical mobilization of 15 cm of the rabbit sciatic and tibial nerve. Capillary nerve blood flow was determined with 16-micron radioactive microspheres. Thirty-seven rabbits were divided into six groups. In the control group A (n = 7), the in situ nerve blood flow was determined. In group B (n = 7), the nerve was mobilized, leaving only the proximal and distal endoneurial vascular supplies; blood flow increased compared with in situ values in most segments. In group C (n = 5), the nerve was mobilized as in group B, but also transected distally; blood flow was markedly decreased in the distal segments but was maintained up to a diameter-to-length ratio of 1:63. In group D (n = 6), the nerve was not mobilized, but was transected proximally and distally; blood flow increased in all segments. In group E (n = 5), the nerve was mobilized and transected proximally and distally, leaving only nerve branches intact; blood flow was significantly higher in segments of the nerve from which nerve branches originated with the nerve receiving blood flow through its branches. In group F (n = 6), the nerve was mobilized, all extrinsic vessels except one were transected, and the proximal and distal nerve was transected; flow was maintained to a diameter:length ratio of 1:41 from the source of blood flow. Therefore, it does appear that long lengths of nerve may be mobilized and transposed while maintaining sufficient blood flow.

[Acute subdural hemorrhage of arterial origin: report of three cases]

Three cases of acute subdural hematoma without head injury, but associated with bleeding from cortical artery are described. Case 1: a 74-year-old male had sudden headache during a bronchial asthma attack followed by deterioration of consciousness. He was deeply comatose on admission, and CT scans revealed a huge subdural hematoma. Evacuation of the large hematoma revealed a spurting cortical branch of the middle cerebral artery beneath it. Case 2: Four days before admission, a 69-year-old male developed headache during a fit of coughing. His CT scans on admission showed a thin subdural hematoma. Because it was increasing in volume, the hematoma was removed surgically. A spurting cortical branch of the middle cerebral artery was seen on the surface of the temporal lobe. Case 3: a 80-year-old male, who had had an operation for inguinal hernia under spinal anesthesia ten days before, suffered a sudden headache just after he stood up. CT scans revealed a thick subdural hematoma. As the clot was being removed a spurting artery was seen in the Sylvian region. In a review of 116 surgical cases of acute subdural hematoma at our institute, the incidence of acute spontaneous subdural hemorrhage was 2.6%. The etiology of nontraumatic hematoma is a matter of controversy. Our three cases suggested that the etiology might be the rupture of a cortical artery at the site of adhesion with the dura mater. This would predispose the artery to tearing with minor trauma. Hematoma evacuation by craniotomy and treatment of the ruptured cortical artery were necessary for favorable outcome.

My memories of Japanese pediatric neurosurgery

At the end of World War II, medical students in Japan knew that the United States of America were the world leaders in medical science, and they dreamed of establishing such a rational and pragmatic brand of medicine in their own country. As the number of motor vehicle accidents increased in parallel with the raid growth of the Japanese economy after the war, the need for neurosurgery also intensified. The number of papers dealing with pediatric issues increased tremendously after the ISPN and JSPN had first held meetings in Japan in September 1973. It seems mandatory for us to back up the activity of the children's hospitals by establishing a subspecialty of pediatric neurosurgery.

Self-reported oral hygiene habits, health knowledge, and sources of oral health information in a group of Japanese junior high school students

The purpose of the present study was to analyze self-reported oral hygiene habits, sources of oral health information, and oral health knowledge in a group of Japanese junior high school students and to determine whether there is a need for improvement in the school's present oral health instruction. A sample of 110 students aged 12-14 in Chiba City were surveyed by means of a questionnaire composed of 24 multiple choice questions. The questions focused on: (1) experience of school-based oral health education, (2) sources of oral health information, (3) knowledge about dental caries, periodontal disease, and the preventive action of fluoride, (4) oral hygiene habits, and (5) dietary behavior. Results showed that more than two-thirds of the students had participated in some kind of school-based oral health education program. Most students (76%) claimed that toothbrushing was the main event attended and 63% claimed that toothbrushing was the main subject they had been taught. The school nurse was identified by 48% of the students as their main source of oral health information in school-based oral health education. When asked to identify their main source of oral health information, most of the students identified "school". Half of the students (48%) identified dental plaque as the main cause of dental caries but only 31%, as the main cause of periodontal disease. Few students (11%) were able to identify the preventive action of fluoride; 58% answered "I don't know"). These results suggest that a meaningful target for the oral health education of children should be the improvement of the school's oral health instruction.

Epitope regions in the heavy chain of Clostridium botulinum type E neurotoxin recognized by monoclonal antibodies

Seventeen monoclonal antibodies (MAbs) were previously established against the heavy chain (Hc) of botulinum type E neurotoxin in BALB/c mice immunized with the type E toxoid. Five MAbs (LE15-5, LE34-6, EK19-7, EK21-4, and AE27-9) showed toxin-neutralizing activity in mice. Two of the five MAbs, EK19-7 and EK21-4, recognized the regions located at amino acid positions 731 to 787 and 811 to 897, respectively. One of the remaining three antibodies (LE34-6) reacted with the amino acid sequence VIKAIN, at amino acid positions 663 to 668, closed by the ion channel-forming domain. It is suggested that the ion channel-forming domain may also be associated with the blocking of acetylcholine release. Furthermore, the amino acid sequence YLTHMRD within 30 residues of the C-terminal region of the Hc component seemed to be recognized by LE15-5. It has been reported that the binding domain of the type E toxin is located on the C-terminal half of the Hc component. Therefore, the neutralizing activity of LE15-5 antibody may be attributed to its ability to block the binding of neurotoxin to the receptor of target cells.

The selectivity of regenerating motor and sensory axons

Functional results of peripheral nerve repair have been hampered by misdirection of regenerating axons. The purpose of this study was to determine in a rat femoral nerve model whether regenerating motor and sensory axons from a proximal nerve stump select the appropriate distal motor or sensory branch. In two experiments, the proximal stump of the motor or sensory branches was sutured to the distal motor sensory stumps, so that the three branches were parallel and the three transected ends faced in the same direction. More regenerated axons from both the proximal motor and sensory stumps entered the distal sensory stump. The number of misdirected axons did not decrease over time. The selective regeneration of motor axons toward the distal motor stump could not be validated. In this study, neurotropism appeared to play a measurable role in sensory axon regeneration, but not in motor axon regeneration. Pruning of the misdirected axons was not demonstrated.

The selectivity of motor axons during regeneration with sensory axons

This study investigated the influence of selective sensory regeneration on less selective motor regeneration in a rat femoral nerve model. The proximal stump of the motor branch to the quadriceps muscle was sutured to the distal stumps of one motor and one sensory branch. Regenerated sensory axons were degenerated secondarily, and motor regeneration was later evaluated. The distal sensory stump attracted both regenerating sensory and motor axons. Misdirected motor axons in the distal branches were not pruned over time. The authors hypothesized that motor regeneration may be been influenced by selective sensory regeneration or non-selective neurotropic attraction.

Posterior fusion for odontoid fracture in an infant--case report

A 2-year-3-month-old girl presented with a rare displaced odontoid fracture. She was managed nonoperatively by manipulation followed by 3-month extracorporeal fixation with a halo brace. However, lateral radiography revealed recurrent dislocation at the base of the odontoid process. Magnetic resonance imaging demonstrated a "synchondrotic slip." She therefore underwent posterior wiring with iliac bone grafting to prevent pseudoarthrosis. The odontoid process had fused to the axis at 4 months postoperatively. Surgical management should be considered as a treatment method for pediatric odontoid fracture because of the difficulties in maintaining long-term immobilization and confirming the union.

Lipid peroxide levels and superoxide-scavenging abilities of Sera obtained from hotbred (Thoroughbred) horses

Hotbred (Thoroughbred) horses were grouped into three classes according to the levels of constant physical exercise (foals, 6 months old; racing horses, 5 years old; horses for breeding, 6-10 years old), and lipid peroxide levels in their sera were measured as thiobarbituric acid-reactive substances. No significant differences were observed among them. The superoxide-scavenging abilities of sera were measured next; to examine the antioxidative properties of hotbreds, and were found to be highest in the racing horses. The higher scavenging ability of the racing horses might contribute to keep their lipid peroxide levels as low as those of the other two groups. HPLC analysis of substances in sera suggested that the presence of albumin-bound bilirubin was one of the reasons for the high superoxide-scavenging ability of sera of the racing horses. When the hotbreds were compared with coldbred (crossbred) horses, the lipid peroxide levels of hotbreds was higher (7.0 +/- 1.2 nmol/ml) than that of coldbreds (2.6 +/- 0.7 nmol/ml). Comparison of the superoxide-scavenging abilities of sera between hotbreds and coldbreds showed that the hotbreds possessed higher scavenging ability than the coldbreds. These results indicated that the lipid peroxide level in sera of hotbreds was higher than that of coldbreds regardless of the higher superoxide-scavenging abilities of sera.

Estimation of fluoride intake in relation to F, Ca, Mg and P contents in infant foods

The purposes of this present study were to determine F, Ca, Mg and P contents of infant foods available in Thailand and Japan in relationship to ionization of F from dietary sources and also to estimate the daily F intake of infants during the first six months of life. Samples of 31 and 24 foods from Thailand and Japan were analysed. Microdiffusion technique was used to separate F from food samples. The combination of an F electrode with an ion analyzer was used to determine F. Determination of Ca and Mg of ashed samples were carried out by the atomic absorption spectrophotometry and Chen, Toribara and Warner method was used in P analysis. F content found in infant formulas and supplemented foods were generally low, especially in infant foods in Thailand, while Ca, Mg and P contents were high in various food items tested. The estimation of daily F intake showed that foods cannot provide an infant with a daily F intake at the optimal level. The results of this study indicate that some food constituents play significant roles in daily F intake by influencing F absorption.

Promotion of sciatic nerve regeneration in rats by a new neurotrophic pyrimidine derivative MS-430

1. The effects of a new neurotrophic pyrimidine derivative of MS-430 on nerve regeneration was examined using Wistar rats whose left sciatic nerve had been subjected to controlled injury. 2. The functional recovery and the packing density of common peroneal nerve axons were significantly enhanced with the administration of 3 mg/kg/day of MS-430. 3. These results suggest that MS-430 is a promising candidate as a neurotrophic drug for clinical use.

Susceptibility to neonatal streptozotocin-induced diabetes in spontaneously hypertensive rats

We studied the difference in the susceptibility to neonatal streptozotocin (STZ) diabetes between spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). Two-day-old female SHR and WKY were injected intraperitoneally with 75.0 mg/kg of STZ or vehicle for control. Hyperglycemia developed in both strains at 4 days of age, but SHR were more hyperglycemic. Overt hyperglycemia developed in SHR with aging after a partial recovery from initial hyperglycemia at 10 days of age, whereas WKY did not develop significant hyperglycemia except shortly after STZ treatment. Percentage of insulin-positive B cells in total islet cells and pancreatic immunoreactive insulin (IRI) content were measured at 4 days, 10 days, 4 weeks, and 12 weeks of age. B cells per islet and pancreatic IRI content were significantly reduced in STZ-treated groups as compared with control in both SHR and WKY at 4 days of age, but later they increased significantly with aging in both strains. However, the reduction in pancreatic IRI content relative to control was significantly greater in SHR than in WKY from 4 days (-94.5 +/- 3.5%, -84.1 +/- 4.8%; p < 0.01) to 12 weeks (-97.1 +/- 2.1%, -28.0 +/- 2.5%; p < 0.05), and the reduction in B cells per islet was also greater in SHR at 4 weeks of age. These results indicated that the initial destruction of pancreatic B cells induced by STZ was greater, and the following regeneration was less in SHR than in WKY. The association of the susceptibility to neonatal STZ diabetes with the development of genetic hypertension in SHR remained to be elucidated.

Prevalence of root caries in a Japanese adult population aged 20-59 years

The purpose of the present study was to investigate the prevalence of root caries in an adult population in Japan. A total of 770 company employees aged 20-59 were examined in 1990. The subjects were all dentate and had 27.2 present teeth on the average. The proportion of gingival recession in this population ranged from 20.1% for the 20-29 year old group to 75.2% for the 50-59 year old group, with an average of 44.0%. In the present study, 3.2% of the subjects showed one or more active root caries. The prevalence of active root caries ranged from 0.4% at age 20-29 to 7.1% at age 50-59. The proportion of persons with active root caries and/or root fillings ranged from 1.3% at age 20-29 to 36.3% at age 50-59. The percentage of subjects with active and/or inactive caries and/or root fillings varied from 3.1% at age 20-29 to 43.4% at age 50-59. The prevalence of active root caries in the subjects at risk (with gingival recession) was 7.4% on the average and ranged from 2.2% at age 20-29 to 9.4% at age 50-59. The percentage of persons with active root caries and/or root fillings in the subjects at risk ranged from 6.7% at age 20-29 to 48.2% at age 50-59. The mean number of teeth with active root lesions was 0.09 per person, and the mean number of teeth with root fillings was 1.25 at age 50-59.(ABSTRACT TRUNCATED AT 250 WORDS)

[Autologous blood transfusion in transurethral resection of the prostate]

With the purpose to avoid the risk of transfusion mediated infection and complication, predeposited autologous blood transfusion was performed. From April 1990 to March 1991, transurethral resection of the prostate (TUR-P) were performed in 27 patients (mean age: 72.5 years) with benign prostatic hypertrophy (BPH). Autologous blood (200-400 ml, mean 244 ml) was predeposited 3 weeks prior to TUR-P in 18 patients (mean age: 73.9 years) and transfused during or just after the operation in 16 (five patients required some homologous blood in addition to their own banked blood). Another three patients were transfused with homologous blood only. The mean values for hemoglobin concentration were 13.7 +/- 0.4 g/dl before blood deposition and 12.8 +/- 0.5 g/dl on the day of operation (recovery rate: 92.5 +/- 2.7%). Although no complication was found in autologous blood transfusion group (11 patients), one case of systemic exanthema and one case of type C hepatitis were observed in homologous blood transfusion group (8 patients). In TUR-P, positive correlations were observed among resected prostate weight (Pro-wt), blood loss (B.) and operation time (Op-T.). Correlation efficient between Pro-wt. and B. was 0.80, that of B. and Op-T. was 0.77 and that of Pro-wt. and Op-T. was 0.85. From these results and ultransomographic measurement of the prostate weight, the amount of blood loss can be calculated preoperatively, there by the amount of blood needed for transfusion will be estimated.(ABSTRACT TRUNCATED AT 250 WORDS)

A new diabetes model induced by neonatal alloxan treatment in rats

Rats treated with streptozotocin (STZ) during the neonatal period have been used as a model of non-insulin-dependent diabetes mellitus. The present study was designed to produce another diabetes model by substituting alloxan for STZ. Male Sprague-Dawley rats of 2, 4 or 6 days of age were injected intraperitoneally with 200 mg/kg of alloxan monohydrate after 16 h fast. Control rats received vehicle alone at 6 days of age. Non-fasting plasma glucose levels in alloxan-treated rats significantly increased after 8 weeks as compared with control, as the age of alloxan treatment advanced (6.6 +/- 0.2 (S.E.M.) mM in control, 8.3 +/- 0.3 mM in 2 days, P < 0.05, 9.8 +/- 0.9 mM in 4 days, P < 0.05, 17.1 +/- 3.5 mM in 6 days, P < 0.05). For the long-term observation, alloxan-treated rats were divided into mild and severe diabetes groups. Hyperglycemia persisted in both groups until 52 weeks (6.5 +/- 0.1 mM in control, 10.3 +/- 0.7 mM in mild diabetes group, 25.3 +/- 3.6 mM in severe group), but significant albuminuria developed only in severe diabetes group. The diabetogenicity of alloxan rapidly increased during the neonatal period, and the neonatal alloxan diabetes model may be useful for studying chronic diabetic complications.

A comparison of daily fluoride intakes from food samples in Japan and Brazil

The purpose of this study was to analyse the fluoride content of Japanese infant foods and foods in Brazil and to estimate daily fluoride intake calculated for a 6-month-old infant which reflects supplemental fluoride increased from infant foods and decreasing breast-feeding and commercial milk-feeding. Fluoride concentrations of 26 samples were assessed by a modified microdiffusion method and fluoride ion selective electrode. The fluoride content varied from 0.53 to 1.33 microgram/g for milk-base formulas, from 0.46 to 2.94 micrograms/g for infant foods in Japan, and from 0.06 to 0.25 microgram/g for foods in Brazil. The daily fluoride intake was calculated according to feeding pattern. The minimum and maximum fluoride values were 0.080 mg/day and 0.248 mg/day, respectively. These fluoride intakes, expressed in milligrams per kg of fluoride intake, ranged from 0.010 to 0.033 mg F/kg body weight. No significant differences in fluoride intake values were found between Japanese infant foods and foods in Brazil. The results of this study indicate that daily fluoride intakes of Japanese infant foods and foods in Brazil could be considered within the optimal recommended level.

Separation and characterization of the C-terminal half molecule of bovine lactoferrin

The C-terminal half molecule (C lobe) of bovine lactoferrin was isolated by mild tryptic hydrolysis of lactoferrin followed by gel filtration and ion-exchange chromatography. The identity of the fragment was established by determining its N-terminal and C-terminal amino acid sequences and comparing them with the amino acid sequence of intact lactoferrin. The isoelectric point of the C lobe ranged between pH 6.2 and 6.5 as measured by isoelectric focusing on polyacrylamide gels. The circular dichroic spectrum in the range of 250 to 350 nm of the C lobe differed slightly from that of intact lactoferrin. The pattern of lectin reactivity was similar for both the C lobe and intact lactoferrin. The C lobe showed partial antigenic identity with intact lactoferrin as demonstrated by the double immunodiffusion method, and pH dependence of iron binding of C lobe is the same as that of intact lactoferrin molecule.

A 5 kDa protein (SCS23) from the 30 S subunit of the spinach chloroplast ribosome

The proteins of the 30 S ribosomal subunits from spinach chloroplasts were investigated using a radical-free and highly reducing (RFHR) method of two-dimensional polyacrylamide gel electrophoresis (PAGE). Twenty-three proteins were resolved on the gel down to the smallest protein of 5 kDa. The N-terminal amino acid sequence of the 5 kDa protein showed no homology with that of any other protein stored in databases, and the copy numbers were estimated to be 0.88 +/- 0.16 and 0.72 +/- 0.04 in the 30 S subunits and the 70 S ribosomes, respectively. The results suggest that the 5 kDa protein, which we have called SCS23, may be an essential ribosomal protein specific to spinach chloroplasts.

Evaluation of a local microsphere injection method for measurement of blood flow in the rabbit lower extremity

The precision of a modified microsphere technique to measure blood flow in the hind limb of the rabbit was determined. Regional (local) injections made via a catheter in the aorta and blood withdrawn through a catheter in the hind limb enabled deposition of a high concentration of microspheres in the tissues while minimizing the number of microspheres needed for accurate measurement. 95Niobium and 141cerium-labeled 16 microns diameter microspheres were used. Blood flow was measured in 15 locations of muscle and skin for simultaneous injections into the aorta and left ventricle (group A), simultaneous injections of a mixture into the left ventricle (group B), and ventricular injections given 1 h apart (group C). No significant differences in mean blood flow measurements were found. Correlation coefficients between local and ventricular injections ranged from 0.89-0.99 and between 0.994 and 0.999 for two simultaneous ventricular injections. The variability over time was greater, with correlations between the first and second injections ranging from 0.13-0.939. Precision of the local technique compared with the ventricular technique can be kept within 30% with five or six animals. The advantage of this technique over ventricular injections is in the measurement of blood flow in small tissue samples when the number of microspheres deposited from ventricular injections is insufficient.

[A case of asymptomatic Dandy-Walker syndrome with cerebellar hemorrhage]

A case of asymptomatic Dandy-Walker syndrome (DWS) complicated by cerebellar hemorrhage is reported. A 65 year-old man was hospitalized for investigation and treatment of disturbance of consciousness. CT scan and MRI showed a large hematoma in the posterior fossa cyst. Postoperative CT scan and MRI revealed the DWS and cerebellar hemorrhage on the left side. This patient had no symptom until 65 years of age, in spite of having DWS. There has been no such case reported in the literature to our knowledge. Derangement of secretion and absorption of cerebrospinal fluid seem to have been the cause of late-onset symptoms after a long well balanced symptom-free period.

Effects of salt loading on glucose tolerance, blood pressure, and albuminuria in rats with non-insulin-dependent diabetes mellitus

We studied the effects of salt loading on glucose tolerance, blood pressure, and albuminuria in rats with mild non-insulin-dependent diabetes mellitus (NIDDM). Two-day-old male Wistar Kyoto (WKY) rats were injected intraperitoneally (IP) with either 75.0 mg/kg streptozotocin (STZ) or vehicle as control. Salt loading was performed as 1% NaCl of drinking solution from 4 weeks until 12 weeks of age (estimated sodium intake: control, 3.14 +/- 0.28 mEq/d in tap-water group, 11.9 +/- 0.95 mEq/d in salt-loaded group; NIDDM, 2.93 +/- 0.16 mEq/d in tap-water group, 12.0 +/- 2.59 mEq/d in salt-loaded group). Oral glucose tolerance, glycosylated hemoglobin (GHb), and pancreatic insulin content at 12 weeks did not differ between the salt-loaded group and tap-water group in both NIDDM and control rats. Urinary sodium excretion was increased in salt-loaded groups of control and NIDDM rats, but systolic blood pressure did not differ among the groups (control, 151 +/- 6 mm Hg in tap-water group, 150 +/- 3 mm Hg in salt-loaded group; NIDDM, 152 +/- 3 mm Hg in tap-water group, 157 +/- 2 mm Hg in salt-loaded group). Urinary albumin excretion was significantly increased in salt-loaded groups (1,790 +/- 272 micrograms/d in control, 1,617 +/- 174 micrograms/d in NIDDM rats) compared with tap-water groups (691 +/- 75 micrograms/d in control, P less than .05; 616 +/- 69 micrograms/d in NIDDM rats, P less than .001), irrespective of STZ injection, but endogenous creatinine clearance was not different among the groups. Furthermore, renal growth was more greatly increased in salt-loaded groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Caries experience in subjects 18-22 years of age after 13 years' discontinued water fluoridation in Okinawa

The purpose of this study is to compare the state of teeth in young adults who had consumed fluoridated water from birth to 5-8 yr of age with the subjects who had non-fluoridated water. The sample consisted of 117 18-22-yr-old female nursing school students. The data obtained in dental examinations were sorted according to their place of residence, and then divided into groups depending on whether their place of residence had been supplied with fluoridated water or not. The fluoride concentration in the water had been 0.7-1.0 ppm in the six water supply systems which were under the control of the US military base. In the subjects who had fluoridated water, the following differences were found when compared to the control subjects: missing teeth and highly progressed caries occurred less frequently; significantly lower caries prevalence was present on free smooth and approximal surfaces; the overall DMFT differences in favor of the fluoridated subjects were small and non-significant.

Synthesis and anti-human immunodeficiency virus type 1 (HIV-1) activity of 3-substituted derivatives of 3'-azido-3'-deoxythymidine (AZT), and inhibition of HIV-1 reverse transcriptase by their 5'-triphosphates

Various 3-substituted 3'-azido-3'-deoxythymidine analogs (2a-i) were prepared by the reaction of 3'-azido-3'-deoxythymidine (1), AZT with N,N-dimethylformamide dialkylacetal or alkyl bromide in the presence of base and their activities against human-immunodeficiency virus type-1 (HIV-1) were evaluated. The corresponding 5'-triphosphate analogs (9) were also synthesized in order to examine inhibition of HIV-1 reverse transcriptase activity. Beyond expectation, some N3-derivatives of AZT were found to reserve the anti-HIV-1 activity to some extent. Among the compounds (2a-i) obtained, 3-allyl-AZT (2e) was the most active against HIV-1 replication in MT-4 cells in vitro with an EC50 value of 0.9 microM. 3-Allyl-AZT 5'-triphosphate (9e), however, exhibited no inhibition of HIV-1 reverse transcriptase activity.

Mutans streptococci in saliva and interdental spaces after topical applications of an antibacterial varnish in schoolchildren

The effect of a chlorhexidine-containing varnish on the levels of mutans streptococci in saliva and in interdental spaces was investigated in 33 15-year-old schoolchildren. Each child was treated with an active (1% chlorhexidine; 1% thymol) and a placebo varnish preparation following the split-mouth technique. The varnishes were applied twice in small amounts into upper interdental areas with a 2-d interval. Mutans streptococci in saliva and interdental plaque was sampled and enumerated during 3 months. The results showed an immediate reduction of the number of interdental mutans streptococci on both test and placebo side after the varnish applications. The levels, however, were significantly lower in the test quadrants compared with the placebo-treated sides after 8, 30 and 90 d. Thus, the findings indicate a slower recolonization in interdental spaces treated with the active preparation. The levels of mutans streptococci in saliva were significantly reduced 1 and 3 months after varnish treatment, suggesting a long-term effect of the antibacterial varnish.

In vitro and in vivo studies of the growth inhibitory effect of a newly synthesized peptide, obiopeptide-1, on mice-bearing methylcholanthrene-induced murine tumours

Novel synthetic Obiopeptide (Obi-1), Glycil-penta-Glutamate, as an immunoregulator, injected intramuscularly to methylcholanthrene (MC) induced tumour bearing mice at 30-100 micrograms per mouse weekly, significantly inhibited tumour growth, compared to that of the untreated control. Numbers of mononuclear cells (MNC) in the spleen obtained from Obi-1 treated and untreated mice were reduced to 64% and 10% of the normal levels, respectively. In histopathological findings, variations of MNC in the spleen was observed in colonies of large MNC and lymphocytes in Obi-1 treated red marrow, while untreated one showed only scattered number of small lymphocytes. A significant O2- production was noted in monolayers of normal macrophages incubated with 0.5 mg Obi-1/ml for 48 hr. Cytotoxicity of spleen MNC cultured with Obi-1 against MC-tumour, Meth A, P-815 and YAC-1 target cells showed less than 10% cytotoxic activity in almost all experiments.

8-Methyladenosine-substituted analogues of 2-5A: synthesis and their biological activities

8-Methyladenosine-substituted analogues of 2-5A, p5'A2'p5'A2'p5'(me8A), p5'A2'p5'(me8A)2'p5'(me8A), p5'(me8A)2'p5'(me8A)2'p5'(me8A), and p5'(me8A) 2'p5'A2'p5'A, were prepared via a modification of a lead ion-catalyzed ligation reaction. These 2-5A monophosphates were converted into the corresponding 5'-triphosphates. Substitution of an 8-methyladenosine residue at the third position (2'-terminus) of the oligonucleotides increased the stability to snake venom phosphodiesterase digestion. Both binding and activation of mouse liver 2-5A dependent ribonuclease (RNase L) by the various 8-methyladenosine-substituted 2-5A analogues were examined. Among the 8-methyladenosine-substituted trimer analogues, the analogues with 8-methyladenosine residing in the 2'-terminal position showed the strongest binding affinity and were several times more effective than 2-5A itself as an inhibitor of translation.

[Bilateral traumatic hemorrhage in the basal ganglia: report of two cases]

Hematomas of the basal ganglia in head injury have long been recognized by pathologists with an interest in head injury but their mechanism has not been revealed clearly. We report two cases of bilateral traumatic hemorrhage in the basal ganglia. Case #1, a 17-year-old male was admitted to our hospital immediately after a traffic accident. Neurological examination revealed that the patient was comatose and had right hemiparesis. CT scan showed bilateral hemorrhage of the basal ganglia and subarachnoid hemorrhage in the perimesencephalic cistern. MRI showed high signal intensity areas in the bilateral basal ganglia, perimesencephalic cistern, cerebral white matter and corpus callosum. The patient was diagnosed as having diffuse axonal injury coinciding with bilateral hemorrhage of the basal ganglia. Stereotactic aspiration for the hematoma of the left basal ganglia was carried out. Case #2, a 75-year-old male was admitted immediately after falling from the roof of his house. Neurological examination revealed no neurological deficit except for headache and nausea. CT scan on the day of injury revealed no abnormality. But CT scan 12 hours following the injury showed bilateral hemorrhage of the basal ganglia. Blood pressure of the patient was within normal range and he was diagnosed as having traumatic bilateral intracerebral hematoma. Conservative treatment was carried out and the patient was discharged 7 days after injury with no neurological deficit. The mechanism of traumatic hemorrhage of the basal ganglia has not been clear. In case #1, diffuse axonal injury (DAI) may have played an important role in the bilateral hemorrhage. But in case #2, non-DAI factor such as vasoparalysis syndrome may have existed.(ABSTRACT TRUNCATED AT 250 WORDS)

Spontaneous recovery from non-insulin-dependent diabetes mellitus induced by neonatal streptozotocin treatment in spontaneously hypertensive rats

We studied the long-term change in glycemic level in a model of non-insulin-dependent diabetes mellitus (NIDDM) induced by neonatal streptozotocin (STZ) treatment in spontaneously hypertensive rats (SHR). Two-day-old male SHR were intraperitoneally injected with 37.5 to 75.0 mg/kg of STZ or vehicle alone as control. According to nonfasting plasma glucose levels at 12 weeks of age, rats were divided into mild (less than 16.8 mmol/L) and severe (greater than or equal to 16.8 mmol/L) diabetes groups. In the mild diabetes group (n = 5), plasma glucose decreased significantly from 14.2 +/- 1.8 mmol/L (mean +/- SEM) at 20 weeks to 7.3 +/- 0.3 mmol/L at 52 weeks (P less than .05) with progressing age. At 52 weeks, overnight fasting plasma glucose levels were significantly lower and serum immunoreactive insulin (IRI) was higher than in controls, respectively (4.1 +/- 0.3 v 5.7 +/- 0.3 mmol/L, P less than 0.01; 625 +/- 50 v 409 +/- 50 pmol/L, P less than .05), and insulinoma was found in 60% of rats. Therefore, the recovery from hyperglycemia may be attributed to the development of insulinoma. In the severe diabetes group (n = 6), plasma glucose remained high until 28 weeks (27.2 +/- 1.5 mmol/L), but thereafter decreased with age, as it did in the mild diabetes group (13.7 +/- 3.5 mmol/L at 52 weeks, P less than .005). However, no insulinoma was found, and the mechanism for the recovery was unclear. The present study demonstrates that hyperglycemia spontaneously ameliorates in a neonatal STZ diabetes model of SHR, although this phenomenon may be strain-related.

[Instrumentation surgery for tumor of the spine]

Spinal instrumentation surgery has come into wide use recently, especially for tumor of the spine. It is very effective for fixing the spine for relieving the patient from pain. But the decision about the indication of instrumentation surgery for tumor of the spine must be made carefully. In cases of double malignant tumors including spinal tumor, it is hard to decide how to treat tumor of the spine. We report a case of 78-year-old male with multiple myeloma of the cervical spine and cancer of the prostate. The patient had been in good health until one year previously, when he started to complain of nuchal pain. He became bedridden with loss of voluntary control of the right upper extremity for the last two months. Then he was admitted to our hospital and radiological examination was carried out. It revealed tumor of the cervical spine and it seemed to be bone metastasis. Further examination revealed that the patient was suffering from multiple myeloma and cancer of the prostate. The tumor of the spine was diagnosed as either multiple myeloma or metastasis of cancer of the prostate. Spinal instrumentation surgery using Luque-rod was carried out as one of the comprehensive treatment plans for double malignant tumors. The instrumentation surgery was effective for fixing the spine and improving the patient's quality of life. In operative procedures, intraoperative spinal cord monitoring was carried out. Intraoperative spinal cord monitoring was indispensable for preventing spinal cord injury. The tumor of the spine was diagnosed as multiple myeloma by pathological examination.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood pressure changes associated with hyperinsulinemia or long-standing diabetes mellitus in spontaneously hypertensive rats

We studied the long-term change in blood pressures of spontaneously hypertensive rats (SHR) treated neonatally with streptozotocin (STZ). Two-day-old male SHR were injected intraperitoneally with 37.5-75.0 mg/kg STZ or with vehicle as control. STZ-treated SHR were divided into mildly or severely diabetic groups according to the nonfasting plasma glucose level at age 12 weeks (the former less than 300 mg/dl, the latter greater than or equal to 300 mg/dl). In the mildly diabetic group (MD) (n = 5), body weight increased and nonfasting plasma glucose was normalized. At 52 weeks of age, fasting plasma glucose levels were lower than controls owing to hyperinsulinemia, and insulinomas were found in 60% of rats. The systolic blood pressure (SBP) as measured by a tail-cuff method, decreased after 40 weeks, and the mean BP from 44 to 52 weeks (188 +/- 4 mmHg) was significantly lower than that in the control group (209 +/- 3 mmHg, p less than 0.01). In the severely diabetic group (SD) (n = 6), hyperglycemia persisted until 52 weeks, although its severity became less marked. BP in the SD group increased after 36 weeks, and the mean BP from 44 weeks to 52 weeks (224 +/- 5 mmHg) was significantly higher than control (p less than 0.05). The present study demonstrated that hypertension was ameliorated in SHR associated with hyperinsulinemia, and deteriorated with long-standing diabetes mellitus.

Synthesis and anti-human immunodeficiency virus (HIV-1) activity of 3'-deoxy-3'-(triazol-1-yl)thymidines and 2',3'-dideoxy-3'-(triazol-1-yl)uridines and inhibition of reverse transcriptase by their 5'-triphosphates

3'-Deoxy-3'-(1,2,3-triazol-1-yl)thymidines (5a, 6a, 8a, 11a, and 12a) and 2',3'-dideoxy-3'-(1,2,3-triazol-1-yl)uridines (5b, 6b, 8b, 11b, and 12b) were synthesized as cyclic analogues of 3'-azido-3'-deoxythymidine (AZT) and 3'-azido-2',3'-dideoxyuridine (CS-87) by the cyclization of 5'-trityl derivatives (1a, b) of AZT and CS-87 using alpha-ketophosphorus ylides and with acetylenic compounds followed by deprotection of the 5'-trityl group. It was hypothesized that the triazole nitrogen atoms could mimic and distorted azido group. However, no significant activity against human immunodeficiency virus type 1 (HIV-1) was observed with any of these compounds. 5'-Triphosphates (17a and 18a, b), prepared from 5a and 6a, b, were inactive against HIV-1 and Rauscher murine leukemia virus (RLV) reverse transcriptases.