SELENBP1 expression in the prefrontal cortex of subjects with schizophrenia.

Selenium binding protein 1 (SELENBP1) messenger RNA (mRNA) has previously been shown to be upregulated in the brain and blood from subjects with schizophrenia. We aimed to validate these findings in a new cohort using real-time PCR in Brodmann's Area (BA) 9, and to determine the disease specificity of increased SELENBP1 expression by measuring SELENBP1 mRNA in subjects with major depressive disorder and bipolar disorder. We then extended the study to include other cortical regions such as BA8 and BA44. SELENBP1 mRNA was higher in BA9 (P = 0.001), BA8 (P = 0.003) and BA44 (P = 0.0007) from subjects with schizophrenia. Conversely, in affective disorders, there was no significant difference in SELENBP1 mRNA in BA9 (P = 0.67), suggesting that the upregulation may be diagnosis specific. Measurement of SELENBP1 protein levels showed that changes in mRNA did not translate to changes in protein. In addition, chronic treatment of rats with antipsychotics did not significantly affect the expression of Selenbp1 in the cortex (P = 0.24). Our data show that elevated SELENBP1 transcript expression is widespread throughout the prefrontal cortex in schizophrenia, and confirm that this change is a consistent feature of schizophrenia and not a simple drug effect.

Comparison between a new electronic bidet and conventional sitz baths: a manometric evaluation of the anal resting pressure in normal healthy volunteers.

BACKGROUND: A bidet has been proposed as a replacement for the sitz bath. Like a sitz bath, it brings water into contact with the perineum. However, the high force of water from commercially used electronic bidets may harm the anus. We developed a new electronic bidet and evaluated its effects on anal resting pressure compared with a warm sitz bath. METHODS: Forty volunteers used the electronic bidet and sitz bath on separate days. The electronic bidet was newly designed with warm (38 °C) water and very low force (10 mN) with a fountain type of flow. Anal resting pressure at the high-pressure zone was measured before (control) and after the electronic bidet and sitz bath. Pressure changes after bidet or sitz bath were expressed as percentages compared with control. Water temperatures and rectal temperatures were also recorded. RESULTS: The anal resting pressures before the electronic bidet and sitz bath were 90.2 ± 24.6 and 88.1 ± 16.8 mmHg, respectively. At 3 min after the electronic bidet and sitz bath, the anal resting pressures were 71.3 ± 23.4 and 69.6 ± 19.8 mmHg, respectively. The pressure changes compared with the control were 78.2 ± 12.9 and 78.1 ± 12.5%, respectively, which were not significantly different. The maximal increase and minimal decrease were not significantly different. The rectal temperature was not elevated, and the water temperature decreased significantly with the sitz bath (p < 0.001). CONCLUSIONS: Our new electronic bidet may reduce the anal resting pressure much like a warm sitz bath does.

Decreased cortical muscarinic M1 receptors in schizophrenia are associated with changes in gene promoter methylation, mRNA and gene targeting microRNA.

Many studies have shown decreased cortical muscarinic M1 receptors (CHRM1) in schizophrenia (Sz), with one study showing Sz can be separated into two populations based on a marked loss of CHRM1 (-75%) in -25% of people (Def-Sz) with the disorder. To better understand the mechanism contributing to the loss of CHRM1 in Def-Sz, we measured specific markers of gene expression in the cortex of people with Sz as a whole, people differentiated into Def-Sz and people with Sz that do not have a deficit in cortical CHRM1 (Non-Def-Sz) and health controls. We now report that cortical CHRM1 gene promoter methylation and CHRM1 mRNA are decrease in Sz, Def-Sz and Non-Def-Sz but levels of the micro RNA (miR)-107, a CHRM1 targeting miR, are increased only in Def-Sz. We also report in vitro data strongly supporting the notion that miR-107 levels regulate CHRM1 expression. These data suggest there is a reversal of the expected inverse relationship between gene promoter methylation and CHRM1 mRNA in people with Sz and that a breakdown in gene promoter methylation control of CHRM1 expression is contributing to the global pathophysiology of the syndrome. In addition, our data argues that increased levels of at least one miR, miR-107, is contributing to the marked loss of cortical CHRM1 in Def-Sz and this may be a differentiating pathophysiology. These latter data continue to support the hypothesis that microRNAs (miRNA) have a role in the underlying neurobiology of Sz but argue they are differentially affected in subsets of people within that syndrome.

SOX2 has a crucial role in the lineage determination and proliferation of mesenchymal stem cells through Dickkopf-1 and c-MYC.

SOX2 is a well-known core transcription factor in embryonic stem cells (ESCs) and has an important role in the maintenance of pluripotency. Recently, SOX2 expression has also been reported in adult stem cells (ASCs), but the role of SOX2 in ASCs remains unknown. In this study, we examined the molecular mechanisms of SOX2 in human mesenchymal stem cells (hMSCs), a type of ASCs, by performing inhibition studies. SOX2 inhibition resulted in altered cell growth and differentiation capabilities. These changes coincided with a decrease in Dickkopf-1 (DKK1), a soluble inhibitor of WNT signaling. Chromatin immunoprecipitation and luciferase assays showed that SOX2 binds to DKK1 and has a positive regulatory role in transcription. The enforced expression of DKK1 in SOX2-inhibited hMSCs reversed the differentiation deformities, but could not abrogate the cell proliferation defect. Proliferation was regulated by c-MYC, whose expression can also be controlled by SOX2. Our study shows that SOX2 directly regulates DKK1 expression and, as a consequence, determines the differentiation lineage of hMSCs. Moreover, SOX2 also regulates proliferation by affecting c-MYC. Therefore, these results suggest that SOX2 might have a specific function by regulating DKK1 and c-MYC in the differentiation and growth of ASCs, which is separate from its roles in ESCs.

Genistein and daidzein repress adipogenic differentiation of human adipose tissue-derived mesenchymal stem cells via Wnt/ß-catenin signalling or lipolysis.

OBJECTIVES: One aspect of the effects of isoflavones against fat deposition might be at least associated with the mechanism by which Wnt/ß-catenin signalling inhibits adipocyte differentiation. However, it remains completely unknown as to whether isoflavones might influence Wnt signalling during commitment of pluripotent mesenchymal stem cells (MSCs) to adipose lineages. In the present study, we have investigated the mechanisms underlying effects of genistein and daidzein, the major soy isoflavones, on anti-adipogenic Wnt/ß-catenin signalling. MATERIALS AND METHODS: Adipose tissue-derived (AD) MSCs were exposed continuously to genistein and daidzein (0.01-100 µm) during adipogenic differentiation (21 days). An oestrogen antagonist, ICI 182,780, was used to determine whether or not the isoflavones activated Wnt signalling via oestrogen receptors (ERs). RESULTS: Genistein and daidzein suppressed adipogenic differentiation of AD-MSCs in a dose-dependent manner and inhibited expression of adipogenic markers, PPARγ, SREBP-1c and Glut 4, from mid-phase differentiation. Microarrays showed that anti-adipogenic effects of genistein were principally attributable to activation of Wnt signalling via ERs-dependent pathway, such as Erk/JNK signalling and LEF/TCF4 co-activators. These findings were supported by evidence that the effects of genistein were offset by ICI182,780. Unlike genistein, daidzein inhibited adipogenesis through stimulation of lipolysis, with for example, PKA-mediated hormone sensitive lipase. This is consistent with the increase in glycerol released from AD-MSCs. In conclusion, understanding that different sets of mechanisms of the two isoflavones on adipogenesis will help the design of novel strategies to prevent observed current epidemic levels of obesity, using isoflavones.

JIP1 binding to RBP-Jk mediates cross-talk between the Notch1 and JIP1-JNK signaling pathway.

Notch1 signaling has a critical function in maintaining a balance among cell proliferation, differentiation, and apoptosis. Our earlier work showed that the Notch1 intracellular domain interferes with the scaffolding function of c-Jun N-terminal kinase (JNK)-interacting protein-1 (JIP1), yet the effect of JIP1 for Notch1-recombining binding protein suppressor of hairless (RBP-Jk) signaling remains unknown. Here, we show that JIP1 suppresses Notch1 activity. JIP1 was found to physically associate with either intracellular domain of Notch1 or RBP-Jk and interfere with the interaction between them. Furthermore, we ascertained that JIP1 caused the cytoplasmic retention of RBP-Jk through an interaction between the C-terminal region of JIP1 including Src homology 3 domain and the proline-rich domain of RBP-Jk. We also found that RBP-Jk inhibits JIP1-mediated activation of the JNK1 signaling cascade and cell death. Our results suggest that direct protein-protein interactions coordinate cross-talk between the Notch1-RBP-Jk and JIP1-JNK pathways.

Treating schizophrenia: novel targets for the cholinergic system.

Cognitive deficits in patients with schizophrenia are the biggest obstacle to achieving an independent and productive lifestyle, with these deficits being refractory to current drug treatments. Significantly, both nicotinic and muscarinic receptors (cholinoceptors) have been shown to have an important role in cognition and are therefore viewed as potential therapeutic targets for drugs designed to lessen cognitive deficits. Importantly, the demonstration that acetylcholinesterase inhibitors, which result in higher synaptic levels of acetylcholine, can reduce the cognitive deficits of schizophrenia suggested that under-stimulation of cholinoceptors could be associated with the cognitive deficits associated with this disorder. This has lead to a focus on the development of receptor agonists, partial agonists and allosteric agonists that can be used to stimulate cholinergic pathways and thus reduce the cognitive deficits of schizophrenia. In addition, muscarinic receptors have now been associated with the modulation of dopamine and may constitute an alternative target for the treatment of psychoses. Given these exciting new therapeutic initiatives, this review will outline current evidence that involves the cholinoceptors in the pathophysiology of schizophrenia and how these data can inform on approaches to more targeted treatments for the disorder.

DNER modulates adipogenesis of human adipose tissue-derived mesenchymal stem cells via regulation of cell proliferation.

OBJECTIVES: In recent years, obesity has become a global epidemic, highlighting the necessity for basic research into mechanisms underlying growth of adipose tissue and differentiation of stem cells into adipocytes, in humans. For better understanding of cell signalling in adipogenesis, the role of DNER (delta/Notch-like EGF-related receptor) in adipogenic differentiation of human adipose tissue-derived mesenchymal stem cells (hAMSC) was investigated. MATERIALS AND METHODS: To assess the role of DNER in hAMSC adipogenesis, hAMSCs were transfected with DNER small interfering RNA (siDNER). Real-time quantitative reverse transcriptase polymerase chain reactions to assess expression levels of adipogenesis-related genes regulated by siDNER, cell cycle and immunoblot analyses were performed. RESULTS: First, it was determined that DNER mRNA was profoundly expressed in hAMSCs and reduced during adipogenic differentiation. Knockdown of DNER altered cell morphology, inhibited proliferation and increased frequency and efficiency of adipogenesis in hAMSC. Expression of CCAAT/enhancer-binding protein delta increased and proportion of cells in S phase decreased by knockdown of DNER, using specific siRNA. Moreover, adipocyte-specific genes including peroxisome proliferator-activated receptor gamma, fatty acid binding protein 4 and perilipin were up-regulated in siDNER compared to the siControl group during adipogenesis in hAMSC. CONCLUSIONS: These results indicate that DNER knockdown in hAMSC accelerated onset of adipogenic differentiation by bypassing mitotic clonal expansion during the early stages of adipogenesis.

Histone deacetylase inhibitors decrease proliferation potential and multilineage differentiation capability of human mesenchymal stem cells.

OBJECTIVES: Histone deacetylase (HDAC) is an important therapeutic target in cancer. Two of the main anticancer mechanisms of HDAC inhibitors are induction of terminal differentiation and inhibition of cell proliferation. To investigate the role of HDAC in maintenance of self-renewal and cell proliferation, we treated mesenchymal stem cells (MSCs) that originated from adipose tissue or umbilical cord blood with valproic acid (VPA) and sodium butyrate (NaBu). MATERIALS AND METHODS: Human MSCs were isolated from mammary fat tissue and cord blood. We performed MTT assay and flow cytometry-based cell cycle analysis to assess self-renewal of MSCs. In vitro differentiation assays into osteogenic, adipogenic, neurogenic and chondrogenic lineages were conducted to investigate MSC multipotency. Immunocytochemistry, Western blot and reverse transcription-polymerase chain reaction were used to interrogate molecular pathways. RESULTS: VPA and NaBu flattened the morphology of MSCs and inhibited their growth. VPA and NaBu activated the transcription of p21(CIP1/WAF1) by increasing the acetylation of histone H3 and H4 and eventually blocked the cell cycle at G2/M phase. The expression level of p16(INK4A), a cdk inhibitor that is closely related to cellular senescence, was not changed by HDAC inhibitor treatment. We performed controlled differentiation into bone, fat, cartilage and nervous tissue to elucidate the role of HDAC in the pluripotency of MSC to differentiate into functional tissues. VPA and NaBu decreased the efficiency of adipogenic, chondrogenic, and neurogenic differentiation as visualized by specific staining and reverse transcription-polymerase chain reaction. In contrast, osteogenic differentiation was elevated by HDAC inhibitor treatment. CONCLUSION: HDAC activity is essential for maintaining the self-renewal and pluripotency of MSCs.

Efficient association study design via power-optimized tag SNP selection.

Discovering statistical correlation between causal genetic variation and clinical traits through association studies is an important method for identifying the genetic basis of human diseases. Since fully resequencing a cohort is prohibitively costly, genetic association studies take advantage of local correlation structure (or linkage disequilibrium) between single nucleotide polymorphisms (SNPs) by selecting a subset of SNPs to be genotyped (tag SNPs). While many current association studies are performed using commercially available high-throughput genotyping products that define a set of tag SNPs, choosing tag SNPs remains an important problem for both custom follow-up studies as well as designing the high-throughput genotyping products themselves. The most widely used tag SNP selection method optimizes the correlation between SNPs (r(2)). However, tag SNPs chosen based on an r(2) criterion do not necessarily maximize the statistical power of an association study. We propose a study design framework that chooses SNPs to maximize power and efficiently measures the power through empirical simulation. Empirical results based on the HapMap data show that our method gains considerable power over a widely used r(2)-based method, or equivalently reduces the number of tag SNPs required to attain the desired power of a study. Our power-optimized 100k whole genome tag set provides equivalent power to the Affymetrix 500k chip for the CEU population. For the design of custom follow-up studies, our method provides up to twice the power increase using the same number of tag SNPs as r(2)-based methods. Our method is publicly available via web server at http://design.cs.ucla.edu.

An ion optics study for KSTAR neutral beam injector development.

Ion optics of three accelerator geometries was studied in terms of an analytic linear optics analysis, a numerical simulation using the IGUN program, an optical multichannel measurement of Doppler-shifted H(alpha) lines, and a water-flow calorimetry on the beam absorbing target. In general, there was a reasonable agreement observed between the four analysis methods and thus the theoretical analyses can be utilized with confidence for design iteration.

Lipid-mediated delivery of brain-specific angiogenesis inhibitor 1 gene reduces corneal neovascularization in an in vivo rabbit model.

Corneal neovascularization, which occurs in many pathologic states of the cornea, reduces the visual acuity. Recently, we found that the extracellular region of brain-specific angiogenesis inhibitor 1 (BAI1-ECR) has antiproliferative activity through functional blocking of alpha(v)beta(5) integrin in endothelial cells. In this study, we investigated the effects of lipid-mediated subconjunctival injection of the BAI1-ECR gene on corneal angiogenesis induced by epithelial debridement by heptanol in the rabbit. When a pEGFP-BAI1-ECR plasmid was given subconjunctivally 1 week after epithelial debridement, green fluorescence was detected in the corneal stroma with expression persisting for 7 days. To test the effect of BAI1-ECR on neovascularization, rabbits were injected with the BAI1-ECR gene or empty vector two or three times at 1-week intervals beginning 1 week after debridement. When measured with biomicroscopy at 1 or 2 weeks after two weekly injections, BAI1-delivered eyes had significantly less neovascularized corneal area than vector-injected ones in both time periods. Similar microscopic results were obtained after three weekly injections of BAI1-ECR. In quantitative histological examination, the BAI1-receiving eyes showed significantly less neovascular area and number of vessels than vector-injected ones. Also, after two weekly injections, BAI1-delivered eyes had decreased neovascularized corneal area equivalent to that of anti-VEGF antibody-injected ones. These results indicate that BAI1-ECR gene delivery effectively reduces experimental corneal neovascularization and suggest that the BAI1-ECR protein can be used as an angiogenesis suppressor in the eye.

C-shaped root canals of mandibular second molars in a Korean population: clinical observation and in vitro analysis.

AIM: To investigate the incidence and morphology of C-shaped root canals of the mandibular second molar in a Korean population. METHODOLOGY: Through clinical observation, randomly selected 272 mandibular second molars of Korean patients were accessed and evaluated after taking radiographs for determination of working length. In an in vitro analysis, 96 extracted mandibular second molars of Korean patients were collected and embedded in resin using an Endodontic cube technique, and were sectioned at intervals of 1 mm. The specimens were then observed with a surgical microscope and were photographed. Canal configurations were assigned to one of three categories: Category I defined a C-shaped outline without any separation; Category II referred to those with canal configurations, where dentine separated one distinct canal from a buccal or lingual C-shaped canal; Category III had two or more discrete and separate canals. RESULTS: In clinical observation, 89 of 272 teeth (32.7%) had C-shaped canals. Of the 96 teeth examined in vitro, 30 (31.3%) had C-shaped canals. Upon in vitro analysis, only 1 tooth at the subpulpal level and 10 teeth at the apical 1 mm level were categorized under Category III. CONCLUSION: There was high prevalence of C-shaped root canals in the mandibular second molars of Koreans. C-shaped canals having semicolon and continuous shapes at the canal orifice have a high possibility of being divided into two or three canals in the apical region.

Preparation, structure, and properties of the corner-shared double cubes [Mo(6)HgQ(8)(H(2)O)(18)](8+) (Q = S, Se) and tungsten analogues.

The purple corner-shared double cube [Mo(6)HgS(8)(H(2)O)(18)](8+) derivative of green [Mo(3)S(4)(H(2)O)(9)](4+), obtained under air-free conditions by the reaction with Hg(0) (metal), is also formed with Hg(I)(2). The Hg(I)(2) reaction is accounted for by the disproportionation Hg(I)(2) <==> Hg(0) + Hg(II), which is a source of Hg(0). X-ray crystallographic information on the blue partially Cl(-) substituted cucurbituril supramolecular assemblies [Mo(6)HgQ(8)Cl(4)(H(2)O)(14)](C(36)H(36)N(24)O(12))Cl(4).14H(2)O (1) and of the Se analogue [Mo(6)HgSe(8)Cl(4) (H(2)O)(14)](C(36)H(36)N(24)O(12))Cl(4).14H(2)O (2) have been determined. The product [W(6)HgSe(8)Cl(4)(H(2)O)(14)](C(36)H(36)N(24) O(12)) Cl(4).14H(2)O (3) has also been obtained, but there is no evidence for [W(6)HgS(8)(H(2)O)(18)](8+) and related forms. The formation of [Mo(6)HgS(8)(H(2)O)(18)](8+) by the reaction of [Mo(3)S(4) (H(2)O)(9)](4+) with Hg(0) under anaerobic conditions maximizes after approximately 40 h in 2.0 M HCl, but requires longer reaction time ( approximately 120 h) in 2.0 M Hpts (p-toluenesulfonic acid) and in 2 M HClO(4) ( approximately 6 days). In 2.0 M HCl there is little absorbance increase until [Mo(3)S(4)(H(2)O)(9)](4+) exceeds 1.2 x 10(-)(3) M, which is explained by a dependence of the formation K (265 M(-1)) on [Mo(3)S(4)(H(2)O)(9)(4+)](2). Furthermore, on dilution of column-purified [Mo(6)HgS(8)(H(2)O)(18)](8+), Beer's law is not obeyed and equilibria involving 2[Mo(3)S(4)(H(2)O)(9)](4+) are apparent. The kinetics of formation of [Mo(6)HgS(8)(H(2)O)(18)](8+) is first-order in [Mo(3)S(4)(H(2)O)(9)](4+), consistent with rate-determining formation of the single cube [Mo(3)HgS(4)(H(2)O)(x)](4+). The oxidations of [Mo(6)HgS(8)(H(2)O)(18)](8+) with [Fe(H(2)O)(6)](3+) and [Co(dipic)(2)](-) are complicated by the release of [Hg(H(2)O)(6)](2+), which also functions as an oxidant. Similar results are obtained for [Mo(6)HgSe(8)(H(2)O)(18)](8+) and the less extensively studied [W(6)HgSe(8)(H(2)O)(18)](8+).

Preparation, structure, and reactivity of Ge-containing heterometallic cube derivatives of [M(3)E(4)(H2O)(9)](4+) (M = Mo, W; E = S, Se).

Studies leading to the incorporation of Group 14 germanium into the incomplete cuboidal clusters [M(3)E(4)(H2O)(9)](4+) (M = Mo, W; E = S, Se) have been carried out. From the clusters [Mo(3)E(4)(H2O)(9)](4+), corner-shared double cubes [Mo(6)GeE(8)(H2O)(18)] are obtained with GeO, by heating with Ge powder at 90 degrees C, or by heating with GeO(2) in the presence of H(3)PO(2) as reductant at 90 degrees C, illustrating the dominance of the double cubes. The yellow-green single cube [Mo(3)GeS(4) (H2O)(12)](6+) is only obtained by controlled air oxidation of [Mo(6)GeS(8)(H2O)(18)](8+) over a period of approximately 4 days followed by Dowex purification. In the case of the trinuclear clusters [W(3)E(4)(H2O)(9)](4+), the single cubes [W(3)GeE(4)(H2O)(12)](6+) are dominant and prepared by the reactions with GeO, or GeO(2)/H(3)PO(2). Conversion of [W(3)GeE(4)(H2O)(12)](6+) to the corresponding double cubes is achieved by reductive addition with BH(4)(-) in the presence of a further equivalent of [W(3)E(4)(H2O)(9)](4+). The crystal structures (pts(-) = p-toluene-sulfonate) of [Mo(6)GeS(8)(H2O)(18)](pts)(8).28H2O, (1); [W(6)GeS(8)(H2O)(18)](pts)(8).23H2O, (2); and [Mo(6)GeSe(8)(H2O)(18)](pts)(8).8H2O, (3); have been determined, of which (2) is the first structure of a W(6) double cube. The M-M bond lengths of approximately 2.7 A are consistent with metal-metal bonding, and the M-Ge of approximately 3.5 A corresponds to nonbonding separations. Of the Group 13-15 corner-shared double cubes from [Mo(3)S(4)(H2O)(9)](4+), [Mo(6)GeS(8)(H2O)(18)](8+) is the least reactive with [Co(dipic)(2)](-) as oxidant (0.077 M(-1) s(-1)), and [Mo(6)SnS(8)(H2O)(18)](8+) is next (14.9 M(-1) s(-1)). Both Ge and Sn (Group 14) have an even number of electrons, resulting in greater stability. In contrast, [W(6)GeS(8)(H2O)(18)](8+) is much more reactive (7.3 x 10(3) M(-1) s(-1)), and also reacts more rapidly with O(2).

Distraction osteogenesis after membranous bone onlay grafting in a dog model.

PURPOSE: The purpose of this experiment was to study the possibility of distraction osteogenesis in a membranous bone onlay graft to the mandible and to clarify the histology of the bone repair. MATERIALS AND METHODS: Four dogs, 5 months of age at the beginning of the experiment, were used for this study. The zygomatic arch was exposed in the subperiosteal plane, and a 3-cm long, full-thickness portion of the arch was harvested. The lateral surface of the mandibular body was exposed in the subperiosteal plane, and the bone was fixed to the lateral surface as a membranous onlay graft using screws. A vertical osteotomy through the graft and underlying mandibular body was done postoperatively at week 1 in dog 1, week 2 in dog 2, week 3 in dog 3, and week 4 in dog 4. An external distraction device was applied to the mandibular body, and distraction was started 7 days after the operation at a rate of 1 mm/d for 10 days. After completion of distraction, the device was left in place for 6 weeks to allow for bony consolidation. Radiographs were carried out at 2, 4, and 6 weeks postdistraction. All dogs were killed 6 weeks after distraction. RESULTS: New bone between the native underlying mandibular segments was generated in the distraction zone in all dogs. New bone was not generated between the segments of the membranous bone onlay graft in dog 1, but was generated in dog 2, dog 3, and dog 4. However, in dogs 2 and 3, the new bone between the segments was less firm, with more fibrous tissue, than the bone between the native underlying mandibular segments. Histologically, the distraction gap between the segments of the membranous bone onlay graft in dogs 2 and 3 was composed of considerable fibrous tissue in the central zone and activated osteoblastic cells forming new bone in the margins. In dog 4, there was much more osteoblastic activity in the distraction gap, and the new bone had the appearance of almost normal cortical bone. CONCLUSION: These findings show that distraction osteogenesis is possible in a membranous bone onlay graft and suggest that the distraction should be performed at least 4 weeks after the onlay grafting.

Mechanism of refractory ceramic fiber- and rock wool-induced cytotoxicity in alveolar macrophages.

OBJECTIVES: Man-made vitreous fibers (MMVFs) can induce cytotoxicity in a way similar to that of other particles, including silica and asbestos fibers. However, as yet the mechanism of MMVF-induced cytotoxicity is still not clear. This report aims to clarify the mechanism of MMVF-induced cytotoxicity in the alveolar macrophage (AM). In this mechanism, an attempt to prove the involvement of the adenosine triphosphate (ATP) generation system and the polyinosinic acid-inhibitable scavenger receptors was made. METHODS: Several parameters were observed for cytotoxicity, such as cell viability, the release of lactic dehydrogenase (LDH) and ATP levels in rat AM's that were treated with refractory ceramic fibers (RF2) and rock wool (RW1). A specially designed ATP generation system was used to determine the effect of MMVF on ATP generation. A scavenger receptor ligand was applied to evaluate the relationship between scavenger receptors and MMVF-induced ATP depletion. RESULTS: A 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium bromide (MTT) assay indicated that both RF2 and RW1 caused a decrease in cell viability and this decrease was concentration-dependent. RF2 and RW1 increased the release of LDH with increasing fiber concentration. From these parameters, RF2 was shown to exhibit greater cytotoxicity than did RW1. Both fibers decreased the intracellular ATP content and this decrease was concentration-dependent. The decrease was more pronounced in RW1 than in RF2 at all fiber concentrations. These fibers suppressed succinate-triggered oxygen consumption. Polyinosinic acid, a ligand of the scavenger receptor, inhibited the MMVF-induced decrease in ATP concentration. CONCLUSION: These results suggest that RF2 and RW1 can induce cytotoxicity and ATP depletion in the AM through the polyinosinic acid-inhibitable scavenger receptor. ATP depletion was the important factor in MMVF cytotoxicity, especially by RW1.

Triangular transchamber suture.

A 64-year-old woman with a fibrous membrane at the lens plane after traumatic loss of all the iris and massive intraocular hemorrhage had posterior chamber intraocular lens (PCIOL) implantation anterior to the fibrous membrane with a triangular transchamber suture to prevent possible PCIOL-corneal touch and enhance the stability of the PCIOL. After 3 years, the PCIOL remained in a good position and visual rehabilitation was satisfactory and without complications.

Purification and characterization of iron superoxide dismutase and copper-zinc superoxide dismutase from Acanthamoeba castellanii.

Two superoxide dismutases (SOD I and SOD II) were purified from Acanthamoeba castellanii and characterized for several biochemical properties. Analysis of the primary structure and inhibition studies revealed that SOD I is iron SOD (Fe-SOD), with a molecular mass of 50 kDa, and SOD II is copper-zinc SOD (Cu,Zn-SOD), with a molecular mass of 38 kDa. Both enzymes have a homodimeric structure consisting of 2 identical subunits, each with a molecular mass of 26 and 19 kDa for SOD I and SOD II, respectively. The isoelectric points of SOD I and SOD II were 6.4 and 3.5, respectively, and there were no isoenzyme forms detected. Both enzymes show a broad optimal pH of 7.0-11.0. Because no differences were observed in the apparent molecular weight of SOD I after addition of the reducing agent 2-mercaptoethanol, the subunits do not appear to be linked covalently by disulfide bonds. However, the subunits of SOD II were covalently linked by intra- and interdisulfide bonds. Western blot analyses showed that the 2 enzymes have different antigenicity. Both enzymes occur as cytoplasmic and detergent-extractable fractions. These enzymes may be potential virulence factors of A. castellanii by acting both as antioxidants and antiinflammatory agents. These enzymes may be attractive targets for chemotherapy and immunodiagnosis of acanthamoebiasis.