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.