Synovial mesenchymal stem cells promote healing after meniscal repair in microminipigs.

OBJECTIVE: The induction of synovial tissue to the meniscal lesion is crucial for meniscal healing. Synovial Mesenchymal stem cells (MSCs) are an attractive cell source because of their high proliferative and chondrogenic potentials. We examined whether transplantation of synovial MSCs promoted healing after meniscal repair of extended longitudinal tear of avascular area in a microminipig model. DESIGN: Longitudinal tear lesion was made in medial menisci and sutured in both knees, and then a synovial MSC suspension was administered for 10 min only in unilateral knee. The sutured meniscus was evaluated morphologically and biomechanically at 2, 4, and 12 weeks. The behavior of transplanted MSCs was also examined. RESULTS: The meniscal healing at 12 weeks was significantly better in the MSC group than in the control group; macroscopically, histologically and by T1rho mapping analysis. Transmission electron microscopic analysis demonstrated that the meniscus lesion was occupied by dense collagen fibrils only in the MSC group. Biomechanical analysis revealed that the tensile strength to failure of the meniscus higher in the MSC group than in the control group in each microminipig. Synovial tissue covered better along the superficial layer from the outer zone into the lesion of the meniscus in the MSC group at 2 and 4 weeks in each microminipig. Synovial MSCs labeled with ferucarbotran were detected in the meniscus lesion and adjacent synovium by MRI at 2 weeks. CONCLUSION: Transplantation of synovial MSCs promoted healing after meniscal repair with induction of synovium into the longitudinal tear in the avascular zone of meniscus in pigs.

Treatment with YIGSR peptide ameliorates mouse tail lymphedema by 67 kDa laminin receptor (67LR)-dependent cell-cell adhesion.

Impaired microcirculation can cause lymphatic leakage which leads to a chronic swelling in the tissues of the body. However, no successful treatment gives any protection against lymphedema due to the lack of well-revealed pathophysiology of secondary lymphedema. Binary image of laminin immunohistochemical expression revealed that distribution of laminin expression localized during surgically induced lymphedema. 67 kDa laminin receptor (67LR) mRNA expression showed a peak at during lymphedema exacerbation. Since the response of 67LR molecules may affect the prevention of inflammation and edema, here we have hypothesized that 67LR ligand of YIGSR peptide could permit reconstructive environment for amelioration of lymphedema and evaluated the effect of YIGSR in a mouse tail model of lymphedema. Indeed, intra-abdominal injections of YIGSR for the first 3 days after inducing lymphedema in the mouse tail model reduced the tail lymphedema on day 14 by 27% (P = 0.035). Histology showed that YIGSR treatment protected lymphedema impairment in epidermis and dermis, and it also inhibited the expansion of intercellular spaces and enhanced especially cell adhesion in the basement membrane as revealed by transmission electron microscopy. Interestingly, the treatment also reduced the local expression of transforming growth factor (TGF)ß. Further elucidation of the mechanisms of 67LR-facilitated lymphangiogenesis contributes to find potential targets for the treatment of lymphedema.

Initial fibroblast attachment to Erbium:YAG laser-irradiated dentine.

AIMS: To evaluate the effects of Erbium (Er):YAG laser irradiation on the morphology of resected dentine surfaces, and to investigate fibroblast attachment to laser-irradiated dentine surfaces. METHODOLOGY: Dentine blocks obtained from single-rooted human teeth were divided into the following groups after sterilization in an autoclave: (i) Laser group treated with Er:YAG laser irradiation (30 mJ per pulse, 10 pps, 60 s); (ii) L-MTAD group treated with laser irradiation as in (i) plus a mixture of doxycycline, tetracycline isomer and citric acid; (iii) RC-Prep group treated with EDTA gel or cream (RC-Prep) and (iv) Control group left untreated. After each treatment, the dentine blocks were incubated with NIH/3T3 fibroblasts cultured to subconfluency in Dulbecco's modified Eagle's medium supplemented with 10% foetal bovine serum and antibiotics. The number of attached cells amongst the groups was analysed statistically at the 5% significance level. The dentine surface morphologies and cell attachments were evaluated by counting assays, histological observations and scanning electron microscopy (SEM). RESULTS: The number of attached cells was significantly higher (P < 0.05) in the Laser group than in the RC-Prep and Control groups at 16 h. Dendritic cell extension of the fibroblasts was only observed in the Laser group at 8 h by SEM. In the histological analyses, significantly more attached cells were found on the dentine surfaces treated with laser irradiation. CONCLUSIONS: Er:YAG laser irradiation induced morphological alterations in dentine surfaces, which may improve the attachment of fibroblasts to dentine.

Magnesium enhances adherence and cartilage formation of synovial mesenchymal stem cells through integrins.

OBJECTIVE: We previously reported that more than 60% of synovial mesenchymal stem cells (MSCs) placed on osteochondral defects adhered to the defect within 10 min and promoted cartilage regeneration. The efficiency of adherence is considered to depend on the interaction between cells and extracellular matrix (ECM), in which integrins may play some important roles. Divalent cations such as calcium, magnesium, and manganese may affect functions of integrins, and the integrins may be involved in differentiation of MSCs. Among divalent cations, magnesium is used in clinical practice as a therapeutic agent and increases the affinity of integrin to ECM. In this study, we investigated whether magnesium enhanced adherence and chondrogenesis of synovial MSC through integrins. METHODS: We performed assays for adherence of human synovial MSCs to collagen-coated slides, in vitro chondrogenesis, ex vivo assays for adherence of human synovial MSCs to osteochondral defect, and in vivo assays for adherence and cartilage formation of synovial MSCs in a rabbit osteochondral defect model. RESULTS: Magnesium increased adhesion of human synovial MSCs to collagen, and this effect was inhibited by neutralizing antibodies for integrin α3 and ß1. Magnesium also promoted synthesis of cartilage matrix during in vitro chondrogenesis of synovial MSCs, which was diminished by neutralizing antibodies for integrin ß1 but not for integrin α3. Ex vivo analyses demonstrated that magnesium enhanced adherence of human synovial MSCs to osteochondral defects. In vivo studies in rabbits showed that magnesium promoted adherence at 1 day and cartilage formation of synovial MSCs at 2 weeks. CONCLUSION: Magnesium enhanced adherence of synovial MSCs through integrins, which promoted synthesis of cartilage matrix at an early phase.

High expression of GADD-45alpha and VEGF induced tumor recurrence via upregulation of IL-2 after photodynamic therapy using NPe6.

NPe6 is a novel second-generation photosensitizer used for photodynamic therapy (PDT). PDT using NPe6 and diode laser (664 nm) induces cell death, inflammatory reactions, immunological responses and damage to the microvasculature. In this study, we evaluated the influence of the immunological responses and of enhanced angiogenesis on the anti-tumor effect of NPe6-PDT using cytokine-overexpressing Lewis lung carcinoma (LLC), LLC-IL-2 cells both in vitro and in vivo. We showed by DNA microarray analysis in vitro that IL-2 and GADD-45alpha (growth arrest and DNA damage 45 alpha) mRNA expressions were induced by 3 h after NPe6-PDT applied at a dose killing 90% of the cells (LD90). IL-2-overexpressing cells (LLC/IL-2 cells) were resistant to the loss of clonogenicity as compared to the parental LLC cells in vitro. Furthermore, in female C57BL/6 mice, NPe6-PDT produced a cure rate of 66.7% in LLC tumors, whereas the cure rate was only 16.6% in LLC/IL-2 tumors, and overexpression of IL-2 caused failure of NPe6-PDT, with tumor recurrence, in vivo. These results suggest that IL-2 expression may play an unfavorable role in attenuation of the antitumor effect of NPe6-PDT. It has been reported that the expression of vascular endothelial growth factor (VEGF), in particular, may cause tumor recurrence after PDT and exert unfavorable effect in relation to attenuate the anti-tumor activity of PDT. Results of immunohistochemical analysis of LLC/IL-2 tumors have revealed that the expressions of GADD-45alpha and VEGF are induced in these tumors after PDT, and in particular, 12 h after PDT, the expression levels were much higher as compared with those in the LLC tumors. The results of our studies using in vitro and in vivo models suggest that the cell death caused by PDT was inhibited by induction of GADD-45alpha expression and that tumor recurrence was promoted by the enhancement of VEGF expression mediated by IL-2 upregulation. Therefore, it is speculated that the use of an IL-2 inhibitor may improve the efficacy of NPe6-PDT.

Breast cancer resistance protein (BCRP) affected acquired resistance to gefitinib in a "never-smoked" female patient with advanced non-small cell lung cancer.

Development of acquired resistance to gefitinib after an initial good response is common. Recently, it was reported that this acquired resistance is related to a secondary mutation associated with a substitution of threonine by methionine at codon 790 (T790M) of the epidermal growth factor receptor (EGFR) gene. In this report, we present a "never smoking" woman with advanced lung cancer who showed acquired resistance to gefitinib, and analysis of autopsy samples revealed no evidence of EGFR mutations in either exons 18-21 or codon 790, and positive immunostaining for breast cancer resistance protein (BCRP). We describe, for the first time, a case in which expression of BCRP was associated with acquired resistance to gefitinib, independent of EGFR mutations.

Effects of dentin characteristics on interfacial nanoleakage.

Water emanating from dentinal tubules during air-drying and light-curing of adhesives leads to entrapment of droplets at the resin-dentin interface and contributes to nanoleakage. This study tested the null hypothesis that characteristics of substrate dentin and type of adhesive used for bonding would not affect the occurrence of nanoleakage. Three self-etch adhesives were used to bond to 4 types of dentin with different characteristics in 12 groups. After silver challenge, nanoleakage percentage was measured within the hybrid layer of each sample. The deep dentin cut perpendicular to tubules always showed a significantly higher nanoleakage percentage compared with that of the other 3 types of dentin. The percentages of nanoleakage within the hybrid layers were not statistically different among adhesives. However, when bonding to deep perpendicular dentin, both all-in-one adhesives revealed more distinct nanoleakage within the adhesive layer compared with that achieved with Clearfil SE Bond, a two-step self-etch adhesive. The results did not support the null hypothesis.

A possible relationship between the anti-cancer potency of photodynamic therapy using the novel photosensitizer ATX-s10-Na(II) and expression of the vascular endothelial growth factor in vivo.

ATX-s10-Na(II) is a novel second-generation photo-sensitizer for photodynamic therapy (PDT). PDT using ATX-s10 and diode laser (670 nm) induces an apoptotic response, inflammatory reaction, immune reaction and damage to the microvasculature. In particular, the vascular shut-down effect plays an important role in the anti-tumor activity of ATX-s10-PDT. It has been reported that PDT induces hypoxia and expression of the vascular endothelial growth factor (VEGF) via the hypoxia-inducible factor 1 (HIF1)-alpha pathway. We hypothesized that the expression of VEGF may cause tumor recurrence after PDT and exert unfavorable effect against the anti-tumor activity of ATX-s10-PDT. In this study, we showed by DNA microarray analysis in vitro that VEGF mRNA expression was induced 3 h after laser irradiation in ATX-s10-PDT. We compared the anti-tumor activity of ATX-s10-PDT against lung cancer cell lines SBC-3 and SBC-3/VEGF, the latter overexpressing VEGF; there was no significant difference in the sensitivity to the PDT between the two cell lines as assessed by clonogenic assay. Furthermore, no statistically significant difference in the anti-tumor effect of PDT, as measured by tumor cures, was found between SBC-3 and SBC-3/VEGF tumors in female Balb/c-nu/nu nude mice in vivo. In conclusion, ATX-s10-PDT may prevent tumor recurrence despite induction of VEGF and promotion of tumor angiogenesis, which are known to enhance tumor proliferation and survival.

Effect of dentin depth on hybridization quality using different bonding tactics in vivo.

OBJECTIVES: Incomplete resin infiltration and polymerization of adhesive contributed to nanoleakage formation. This study tested the null hypothesis that adoption of different bonding tactics and dentine depth will not affect hybridization quality in vivo. METHODS: Class V cavities were prepared on the labial/buccal surface of monkey teeth. They were bonded by Single Bond (a two-step total-etch adhesive), Clearfil SE Bond (a two-step self-etch adhesive), or Clearfil S(3) Bond (an all-in-one self-etch adhesive). Combined nanoleakage analysis and quantitative immunolabeling evaluation were carried out in the hybrid layer formed in both cervical superficial and deep dentine. RESULTS: Single Bond showed reticular and spotted nanoleakage while Clearfil SE Bond and Clearfil S(3) Bond presented only a spotted one. While Single Bond showed increased concentration of labeling of type I collagen within the deep part of the hybrid layer, two self-etch adhesives-Clearfil SE Bond and Clearfil S(3) Bond revealed a homogeneous labeling pattern, even if the latter presented a significantly increased labeling index in deep dentine. CONCLUSIONS: Different bonding tactics showed different nanoleakage patterns and immunolabeling index, and was influenced by dentine depth at different levels in vivo.

Identification of the protein product of the Coch gene (hereditary deafness gene) as the major component of bovine inner ear protein.

In order to better understand the cause of hereditary hearing impairment, we have performed a proteomic analysis of the inner ear proteins using two-dimensional gel electrophoresis. In the process of analysis, we have found very unique properties of the bovine homologue of the human COCH gene product. The COCH gene is responsible for one of the hereditary hearing impairments, DFNA9, and was recently suggested to be a possible genetic factor contributing to Ménière's disease. The Coch protein constitutes 70% of bovine inner ear proteins and is composed of 16 different protein spots, with charge and size heterogeneity. Heterogeneity of this protein suggests that the Coch gene is processed in several ways, at the transcriptional and/or posttranslational level. Much knowledge has accumulated about the hereditary hearing impairment genes; however, little research has been done regarding the protein products of those genes. This is the first report to characterize the Coch protein. Study of the Coch protein might provide more information on the mechanism of hearing and vestibular disorders.

Characterization of Ca(2+) signaling pathways in human mesenchymal stem cells.

Human mesenchymal stem cells (HMSC) have the potential to differentiate into many cell types. The physiological properties of HMSCs including their Ca(2+) signaling pathways, however, are not well understood. We investigated Ca(2+) influx and release functions in HMSCs. In Ca(2+) imaging experiments, spontaneous Ca(2+) oscillations were observed in 36 of 50 HMSCs. The Ca(2+) oscillations were completely blocked by the application of 10 micro M cyclopiazonic acid (CPA) or 1 micro M thapsigargin (TG). A brief application of 1 micro M acetylcholine (ACh) induced a transient increase of [Ca(2+)](i) but the application of caffeine (10 mM) did not induce any Ca(2+) transient. When the stores were depleted with Ca(2+)-ATPase blockers (CPA or TG) or muscarinic agonists (ACh), store-operated Ca(2+) (SOC) entry was observed. Using the patch-clamp technique, store-operated Ca(2+) currents (I(SOC)) could be recorded in cells treated with ACh or CPA, but voltage-operated Ca(2+) currents (VOCCs) were not elicited in most of the cells (17/20), but in 15% of cells examined, small dihydropyridine (DHP)-sensitive Ca(2+) currents were recorded. Using RT-PCR, mRNAs were detected for inositol 1,4,5-trisphosphate receptor (InsP(3)R) type I, II, and III and DHP receptors alpha1A and alpha1H were detected, but mRNA was not detected for ryanodine receptor (RyR) or N-type Ca(2+) channels. These results suggest that in undifferentiated HMSCs, Ca(2+) release is mediated by InsP(3)Rs and Ca(2+) entry through plasma membrane is mainly mediated by the SOCs channels with a little contribution of VOCCs.

Self-organization mechanism in a bone-like hydroxyapatite/collagen nanocomposite synthesized in vitro and its biological reaction in vivo.

When bone is lost due to injury and/or illness, the defects are generally filled with natural bone because artificial bone materials have problems of bioaffinity. However, natural bone also has supply and infection problems. If an artificial material has the same biological properties as bone, it can replace natural bone for grafting. We synthesized a hydroxyapaite (HAp) and collagen (Col) composite by a simultaneous titration coprecipitation method using Ca(OH)2, H3PO4 and porcine atelocollagen as starting materials. The composite obtained showed a self-organized nanostructure similar to bone assembled by the chemical interaction between HAp and Col. The consolidated composite by a cold isostatic pressure of 200 MPa indicated a quarter of the mechanical strength of bone. It also indicated the same biological properties as grafted bone: The material was resorbed by phagocytosis of osteoclast-like cells and conducted osteoblasts to form new bone in the surrounding area. This HAp/Col composite having similar nanostructure and composition can replace autologous bone grafts.

Bone with a vascular flap induced from fat tissue with the use of rhBMP-2 in rats.

Here we report that successful bone formation with a vascular flap inside a cylindrical mold was induced from fat tissue with the use of recombinant human bone morphogenetic protein-2 in rats. Fat tissue connected to blood vessels was prepared to fit into the mold and implanted intramuscularly into the hind leg in Wistar rats. RhBMP-2 (20 micro g) was applied in a collagen sheet previously placed on the inside surface of the mold. Bone formation was confirmed radiologically and morphologically at 2, 4, and 8 weeks after the surgery. In the control group without rhBMP-2 or the group with ligation of the blood vessels before the implantation, bone formation was not observed. Our success in bone formation having a definite size, shape, and blood supply may lead to a therapeutic approach to effective bone reconstitution. The present study is the first report on bone induction from fat tissue by rhBMP-2 in vivo.

Correlations between the apparent diffusion coefficient, water content, and ultrastructure after induction of vasogenic brain edema in cats.

OBJECT: The authors examined the correlation between changes in the apparent diffusion coefficient, regional water content, and tissue ultrastructure after vasogenic brain edema. METHODS: Vasogenic edema was induced in the white matter of six cats by cortical cold lesioning. The trace of diffusion tensor (Trace[D]) obtained from magnetic resonance imaging to measure the orientationally averaged water diffusibility was compared with the corresponding tissue water content determined by gravimetric studies and with ultrastructural water localization. Edema fluid had spread to the subcortical and deep white matter by 4.5 hours postlesioning. The increase in Trace(D) showed a significant linear correlation with the increase in tissue water content, both in the subcortical and deep white matter as follows: y = 45.5x - 2367 (r = 0.94) and y = 37.0x - 1769 (r = 0.93), respectively, where x is the water content (gram water/gram tissue) and y the Trace(D) (x 10(-6) mm2/second). On histological examination, nerve fibers were found to be dissociated in the white matter and the extracellular space was markedly enlarged with protein-rich fluid. No noticeable hydropic swelling of the cellular components was observed. CONCLUSIONS: A linear correlation was observed between increases in Trace(D) and increases in extracellular water volume in in vivo vasogenic brain edema. A similar correlation between the subcortical and deep white matter showing different arrangements of nerve fibers (parallel compared with intermingled, respectively) indicated that measurement of Trace(D) is a suitable parameter for the evaluation of vasogenic brain edema.

Transient structures of wave patterns arising in the wave regeneration of subalpine coniferous forests.

In wave-regeneration phenomena observed in the subalpine coniferous forests, mainly consisting of Abies species, the blighted forests present various shapes in the course of development, spots at the initial stage turning into arches and finally into long whitish stripes. Because the wave-regeneration could not be followed in the field without long term studies, a simple model has been elaborated to simulate the various different dieback structures observed in the real forests. This model, based on cellular automata, is employed to analyze the power spectral density of canopy tree height fluctuations in the wave-regenerated forests. The results demonstrate that almost all the dieback structures observed in the field can be generated by this simple model, by varying the wind direction and its strength by some stochasticity. The power spectrum density presents various shapes in the course of development, white noise type at the initial stage turning into Lorentz type and finally into 1/f type power spectrum (spatial Fourier frequency).

Time course of trace of diffusion tensor [Trace(D)] and histology in brain edema.

We examined the correlation between changes in the trace of diffusion tensor [Trace(D)], regional water content and tissue ultrastructure relating to cellular (cytotoxic) and vasogenic brain edema. Cellular edema was induced by left middle cerebral artery occlusion in cats (Kuroiwa T et al., 1998). Vasogenic edema was induced in the white matter of cats by a cold lesion (Kuroiwa T et al., 1999). In cellular edema, the water content increase correlated linearly with the Trace(D) decrease in both the gray and white matter. However, both the slopes and intercepts of the correlation lines were significantly different. Hydropic astrocytic swelling was seen in both structures, and in the white matter, oligodendrocytic and myelinated axonal swelling were observed. In vasogenic edema, the increase in Trace(D) showed a significant linear correlation with the increase in tissue water content. Histologically, nerve fibers were dissociated and the extracellular space was markedly enlarged with protein-rich fluid. These result showed that the different slopes and intercepts of the water content--Trace(D) correlation lines for different subtype of brain edema, which reflect different ultrastructural localization of water, should be taken into account when evaluating brain edema using Trace(D) mapping.

Needle aspiration biopsy of vulvar endometriosis. A case report.

Vulvar involvement by endometriosis is extremely rare. A patient presented with a vulvar tumor and was diagnosed on needle aspiration biopsy and subsequently on histopathology as having endometriosis of the vulva. The treatment offered was conservative, local excision of the tumor. The patient was well and free of complaints when last seen in the Outpatient Department, at six months of follow-up. Needle aspiration biopsy as a diagnostic tool in vulvar tumors and the histogenesis of the endometriosis are discussed.

Differential diagnosis of calcium pyrophosphate dihydrate deposition of the temporomandibular joint.

Calcium pyrophosphate dihydrate (CPPD) deposition disease (pseudogout) of the temporomandibular joint (TMJ) is rare. It is characterized by the presence of crystal deposits that are birefringent under polarized light. Although these crystals are characteristically weakly birefringent, some other crystals such as those of calcium oxalate, synthetic steroids, and ethylenediaminetetraacetic acid are also birefringent. The differential diagnosis should therefore be based on a quantitative analysis of crystals or observation of the crystal structure in calcified sections. We present a case of CPPD deposition disease of the TMJ and report on the value of such an analysis to substantiate the diagnosis.

[A morphological study of interactions of Candida albicans and Streptococcus mutans].

Denture stomatitis is caused mainly by infection of Candida albicans and Streptococcus mutans, the most predominant members of the bacterial flora on denture surfaces. The purpose of this study was to investigate the adhesion in vitro of C. albicans and of S. mutans to acrylic surfaces and their interactions. Concentrations of C. albicans and of S. mutans (mutational phase I and III in which activities of glucosyltransferases are higher and lower respectively) were of high levels (> or = 5.0 x 107 colony-forming-units per ml; CFU/ml). The colonies in brain-heart-infusion (BHI) broth added 5% sucrose incubated at 37 degrees C for 18 and 72 hours. Then the samples were dried and evaporated, and examined by S-700 and S-4100 SEM (HITACHI). It was found that S. mutans (mutational phase I) synthesized water-insoluble glucans concomitantly with the adhesion of both S. mutans and C. albicans to the acrylic surfaces. Also, adhesion of C. albicans, mediated by cell-to-cell interactions with S. mutans (especially mutational phase III), to the surfaces was observed.

Validity of mid-arm muscular area measured by anthropometry in nonobese patients with increased muscle atrophy and variation of subcutaneous fat thickness.

BACKGROUND: The anthropometric measurement of mid-arm muscular area (MAMA) involves overestimation because of various assumptions, this overestimation being progressive with increasing adiposity. However, the effects of muscle atrophy and variation of the subcutaneous fat thickness have remained uncertain. OBJECTIVES: The validity of MAMA estimated by anthropometry was examined by comparing with MAMA measured by computed tomography (CT) in a nonobese population. The effects of muscle atrophy and variation of the subcutaneous fat thickness on the validity of MAMA were examined by new indices. SUBJECTS/METHODS: The relative MAMA was compared between the anthropometric and CT methods in 45 patients. New indices were introduced for assessing muscle deformity (muscle deformity index, MDI) and subcutaneous fat variation (SFVI). The effects of MDI, SFVI and age on the difference of MAMA between the anthropometric and CT methods were investigated. RESULTS: MDIs were positively correlated with age in males (r=0.47, P<0.05) and females (r=0.66, P<0.001). SFVI was positively correlated with age only in females (r=0.54, P<0.01). Even in these patients, the relative MAMA estimated by anthropometry was significantly associated with that measured by CT (r=0.85, P<0.0001 in males and r=0.90, P<0.0001 in females). A Bland-Altman plot indicated that the difference between both methods was relatively small, although increased adiposity might be a source of overestimation for anthropometric MAMA measurement. CONCLUSIONS: MAMA estimated by anthropometry was a reliable indicator of muscle mass in patients with muscle atrophy and varying thickness of subcutaneous fat in lean patients.