Mandibular reconstruction using a poly(L-lactide) mesh combined with autogenous particulate cancellous bone and marrow: a prospective clinical study

The purpose of this study was to evaluate the stability and viability of mandibular bone regeneration using a poly(L-lactide) (PLLA) mesh and autogenous particulate cancellous bone and marrow (PCBM). Sixty-two procedures were undertaken at eight hospitals (22 malignant tumours, 30 benign tumours, five cysts, two osteomyelitis, two trauma, and one atrophy of the alveolar ridge); the success rate was 84%. The follow-up period was between 9 and 200 months (mean 88.2 months). Consequently, bone regeneration at 6 months postoperation was excellent in 35 cases (57%), good in 17 cases (27%), and poor in 10 cases (16%). In six of the 'poor' cases, the PLLA mesh was removed due to local infection early after surgery. Bone resorption>20% was observed in only one of 46 cases with a follow-up term of >1 year. There were no signs of any other adverse effects except in one case where a section of the tray broke off late in the follow-up period. It is concluded that this method is stable and effective due to favourable morphological and functional recovery and low invasiveness. It may thus be a useful alternative procedure for mandibular reconstruction.

Impact of five SNPs in dopamine-related genes on executive function

OBJECTIVES

Dopamine neurotransmission is a critical factor for executive function, which is controlled by the prefrontal cortex in humans. Although the contribution of genetic factors to the regulation of brain dopaminergic activity is widely acknowledged, identification of a genotype-phenotype association has not yet been clearly established. In this study, we therefore evaluated the effects of five functional single-nucleotide polymorphisms (SNPs) in specific genes related to dopamine neurotransmission on executive function in a general population.

MATERIALS AND METHODS

Participants of the health examination at the Shimane Institute of Health Science were recruited for this study (n = 964). To evaluate executive function, the Frontal Assessment Battery (FAB) was administered. SNPs were genotyped using the TaqMan method.

RESULTS

A significant association was found between an SNP in the catechol-O-methyltransferase (COMT) gene (rs4680) encoding the low-activity Met allele and FAB score (P = 0.003). Of note, the flexibility subset of the FAB was associated with the SNP in COMT (P = 0.003) after adjustment for confounding factors. The generalized multifactor dimensionality reduction method identified that the combination of two SNPs in the COMT gene (rs4680) and the dopamine D4 receptor gene (rs1800955) had a significant effect on FAB score.

CONCLUSIONS

Our study indicates a contribution of rs4680 in the COMT gene to the variability in executive function, as assessed by the FAB. In addition, we have indicated that a complex gene-gene interaction between SNPs in the genes related to dopamine neurotransmission may influence executive function in a general population.

Delaying embryo development by storing at 4°C for synchronization to recipients in microinjection technique in rabbits

Short-term storage of embryos at low temperature induces developmental arrest of the embryo and would appear to be a valuable aid in embryo-transfer techniques to avoid wasting embryos. Embryo storage at 4°C was examined to allow synchronization with embryo-transfer recipients using the microinjection technique. Superovulation was induced in female Japanese White donor rabbits four days before mating with males. At the same time, control recipients were injected with human chorionic gonadotropin (hCG) to allow synchronization (R1); the hCG injections were delayed by 24 h in the experimental group (R2). DNA constructs for expressing human C-reactive protein or apolipoprotein AII were microinjected into the male pronuclei of the ova. The microinjected embryos were immediately transferred to recipients (R1) or stored at 4°C in phosphate-buffered saline containing 10% fetal bovine serum. After 17-20 h, the stored embryos were incubated at 37°C for one hour, and the morphologically normal embryos were transferred to recipients (R2). In the R1 rabbits, 855 embryos were transferred to 29 recipients, and 72.4% of the recipients became pregnant. Seven of the 84 offspring were transgenic. In the R2 rabbits, 478 embryos were transferred to 16 recipients, and 62.5% of the recipients became pregnant. Two of the 39 offspring were transgenic. There were no differences in pregnancy rate, litter size and transgenic integration rate between R1 and R2. These results suggest that the short-term 4°C storage of microinjected embryos can be a valuable method for synchronization with recipients, and reducing wastage of embryos and the sacrifice of rabbits.

Short communication: Molecular typing of Prototheca zopfii from bovine mastitis in Japan

Prototheca zopfii causes bovine mastitis, resulting in reduced milk production and the secretion of thin watery milk with white flakes. Prototheca zopfii has been biochemically and serologically divided into at least 2 genotypes, P. zopfii genotype 1 and P. zopfii genotype 2. The latter is known to be the main causative agent of bovine protothecal mastitis. Prototheca zopfii was later reclassified into 5 varieties: var. zopfii (genotypes 1 and 2), var. 1 (formerly Prototheca blaschkeae), var. 3 (formerly P. moriformis), and var. portoricensis. In this study, the 18S ribosomal DNA sequences of diverse clinical specimens from different areas in Japan were studied to clarify the pathogenicity of P. zopfii var. zopfii. The phylogenetic tree revealed that all genotype 2 isolates were grouped in a cluster of P. zopfii var. zopfii SAG 2021(T) (type strain genotype 2), and were independent from the cluster of the genotype 1 isolates. Thus, all isolates from bovine mastitis in Japan were identified as P. zopfii genotype 2. Therefore, P. zopfii var. zopfii genotype 2 is associated with bovine mastitis.

Angiogenic activity of subchondral bone during the progression of osteoarthritis in a rabbit anterior cruciate ligament transection model

OBJECTIVE

To investigate the longitudinal angiogenic activity of subchondral bone and cartilage during the progression of osteoarthritis (OA) using a rabbit model of OA.

MATERIALS AND METHODS

OA was surgically induced by anterior cruciate ligament transaction (ACLT) in left knee of 12 months old female New Zealand white rabbits (n = 33). Histological examination, immunohistochemistry, and angiogenic activity assay was done at 0, 2, 4, 6, 8, 12 weeks after ACLT. Histologic evaluation was performed with haematoxylin and eosin, safranin-O staining to assess the OA change of medial femoral condyle (MFC) and lateral femoral condyle (LFC). CD31 immunohistochemistry was performed to confirm the vascular invasion at osteochondral junction. A co-cultured tubule formation assay was conducted to evaluate angiogenic activity of the subchondral bone and cartilage of MFC and LFC as well as synovium. Association between histological changes, angiogenic activity, and vascular invasion were evaluated.

RESULTS

OA changes increased in a time-dependent manner both in MFC and LFC. Angiogenic activity of subchondral bone showed a monomodal change during the OA progression, achieved a peak in the early to progressive stage and decreased to normal level in the late stage of OA. Surge of vascular invasion was observed following the increase of angiogenic activity in the progressive stage of OA. Angiogenic activity of cartilage did not change during the course of OA progression.

CONCLUSION

Angiogenic activity of subchondral bone was elevated in the early to progressive stage of OA and vascular invasion into the osteochondral junction followed.

Swollen head syndrome in broiler chickens in Japan: Its pathology, microbiology and biochemistry

Four-to-seven-week-old broilers with swollen head syndrome (SHS) from 4 different districts of Japan were examined for pathological, microbiological and biochemical findings. Periocular and mandibular subcutaneous swelling, sometimes accompanied by ocular, hepatic and cardiac lesions were observed. Histologically, diffuse fibrinopurulent inflammation with focal granulomatous lesions was characteristic of subcutaneous tissue of the head, especially periocular tissue. The air spaces of the cranial bones and middle ear showed fibrinopurulent inflammation. Upper respiratory lesions (rhinitis, sinusitis and tracheitis) were always present in chickens with SHS. The characteristic lesions of chicken colibacillosis, i.e. fibrinopurulent serositis, panophthalmitis, fibrinous thrombi in sinusoids of the liver and fibrinous exudation in the ellipsoids and lymphoid follicles of the spleen, were occasionally seen. No virological agents could be isolated. Turkey rhinotracheitis (TRT) virus gene was detected in tracheas from two flocks by reverse transcriptase polymerase chain reaction and serum antibodies against TRT virus were present. Escherichia coli and Staphylococcus aureus were isolated from subcutaneous lesions. Serum alpha(1)-acid glyco-protein, an acute phase protein, was present at high concentration in chickens with SHS. This study suggests that upper respiratory lesions induce E. coli invasion into subcutaneous connective tissue adjacent to the infraorbital sinus and nasal cavity, and SHS in this study may possibly be a local infection of E. coli in facial subcutaneous connective tissue.

Attempts to reproduce swollen head syndrome in specific pathogen-free chickens by inoculating with Escherichia coli and/or turkey rhinotracheitis virus

Attempts to reproduce swollen head syndrome (SHS) lesions were carried out in specific pathogen-free (SPF) chickens. In Experiment 1, chickens inoculated into the submucosal tissue of the nasal membrane or subcutaneous tissue of eyelids with four different strains of Escherichia coli, developed typical SHS lesions; purulent and necrotic lesions of facial subcutis (especially around their eyelids), periocular connective tissue, infraorbital sinus, air spaces, middle ears and eyeballs. The lesions elsewhere included splenic necrosis with fibrinous exudation, fibrin thrombi in hepatic sinusoids, and fibrinopurulent epicardi-tis and perihepatitis which occasionally accompanied lesions in SHS cases. In Experiment 2, SPF chickens inoculated intranasally with turkey rhinotracheitis (TRT) virus and/or E. coli showed no significant lesions in the facial skin, upper respiratory tract or other organs. However, the presence of TRT antibodies demonstrated that the virus infected the chickens. This study suggests that E. coli may play a significant role in the pathogenesis of SHS, but that the significance of TRT virus in the pathogenesis is still to be clarified.

Quantification of chicken anaemia virus by competitive polymerase chain reaction

A quantitative method for chicken anaemia virus (CAV) was developed using competitive polymerase chain reaction (PCR). Competitive template was constructed by deletion of 33 nucleotides from a wildtype DNA clone of CAV. Quantification of CAV DNA molecules by the competitive PCR was rapid and highly reproducible when compared with conventional infectivity titration methods. The ratios of the viral DNA molecules and infectivity titres in MDCC-MSB1 cells varied between 1.3 and 3.55 log(10) among several isolates, suggesting the existence of different infection efficiencies to MDCC-MSB1 cells by isolates. The competitive PCR will be useful for studying CAV infection in vivo and/or in vitro.

Development of 3D microwave imaging reflectometry in LHD (invited)

Three-dimensional (3D) microwave imaging reflectometry has been developed in the large helical device to visualize fluctuating reflection surface which is caused by the density fluctuations. The plasma is illuminated by the probe wave with four frequencies, which correspond to four radial positions. The imaging optics makes the image of cut-off surface onto the 2D (7 × 7 channels) horn antenna mixer arrays. Multi-channel receivers have been also developed using micro-strip-line technology to handle many channels at reasonable cost. This system is first applied to observe the edge harmonic oscillation (EHO), which is an MHD mode with many harmonics that appears in the edge plasma. A narrow structure along field lines is observed during EHO.

Elevated BAFF levels in the cerebrospinal fluid of patients with neuro-Behçet's disease: BAFF is correlated with progressive dementia and psychosis

Neuro-Behçet's disease (NBD) is a serious complication of Behçet's disease. Generally, NBD patients with a chronic course are refractory to immunosuppressive treatment, resulting in the deterioration of personality. In this study, levels of B cell-activating factor belonging to the TNF family (BAFF) were measured in the cerebrospinal fluid (CSF) from 18 patients with NBD, 27 patients with epidemic aseptic meningitis (AM), 24 patients with multiple sclerosis (MS) and 34 healthy controls. BAFF levels in patients with NBD were significantly elevated compared with healthy controls, but showed no statistically significant elevation compared with either of the disease controls. In contrast, CSF IL-6 levels were slightly elevated in patients with NBD and significantly elevated in patients with AM and MS compared with healthy controls. Patients with NBD were subdivided into two groups according to their clinical course (eight patients with a slowly progressive course presenting with psychosis and dementia and 10 patients with an acute course including aseptic meningitis, brainstem involvement and myelopathy). BAFF levels were significantly increased in those with a slowly progressive course compared with those with an acute course. CSF BAFF levels did not correlate with serum BAFF levels, CSF cell counts or CSF IL-6 levels in patients with NBD. These data suggested that BAFF was produced within the central nervous system and may be associated with the development of NBD, particularly with a progressive course.