Irisin promotes odontogenic differentiation and angiogenic potential in human dental pulp cells.

AIM: To determine whether irisin, a newly discovered myokine that links exercise-induced and metabolic homeostasis, is able to promote odontogenic differentiation and angiogenesis in human dental pulp cells (HDPCs). METHODOLOGY: Cell viability in the presence of irisin was measured. Real-time PCR and Western blot analysis were performed to evaluate the expression levels of irisin, odontogenic and angiogenic markers. The involvement of mitogen-activated protein kinase (MAPK) and the protein kinase B (Akt) signalling pathway was evaluated by Western blot. To evaluate mineralization nodule formation, alkaline phosphatase (ALP) staining and alizarin red S staining were performed. Scratch wound assays were performed to evaluate the effects of irisin on cell migration. The data were analysed using one-way analysis of variance (anova) followed by Tukey post hoc test and Student's t-test. Statistical significance was considered at P < 0.05. RESULTS: Irisin significantly promoted odontogenic differentiation as evidenced by formation of mineralized nodules, induction of ALP activity and upregulation of odontogenic and angiogenic markers (P < 0.05). Scratch wound assays revealed that irisin significantly increased migration of HDPCs (P < 0.05). Phosphorylation of both MAPK and Akt was increased by irisin. MAPK and Akt inhibitors inhibited mineralization, cell migration and the increased expression of odontogenic and angiogenic markers. CONCLUSIONS: Irisin promoted odontogenic differentiation and mineralization and has the potential for angiogenesis through activation of the MAPK and Akt signalling pathways in HDPCs.

18F-FDG PET/CT for the pre-surgical localization of epileptogenic focus among paediatric patients with drug resistant epilepsy in Malaysia: perspective of a nuclear medicine physician.

BACKGROUND: Scalp video electroencephalography monitoring (VEM) and brain MRI sometime fail to identify the epileptogenic focus (EF) in patients with drug resistant epilepsy (DRE). 18F-FDG PET/CT has been shown to improve the detection of EF in patients but is not widely used in Malaysia. Thus, the objective of this study was to identify whether 18F-FDG PET/CT conferred an added benefit in the pre-surgical evaluation of DRE. METHODS: Retrospective review of 119 consecutive paediatric patients referred for 18F-FDG-PET/CT at the Department of Nuclear Medicine of the National Cancer Institute, Putrajaya. All had DRE and underwent evaluation at the Paediatric Institute, Hospital Kuala Lumpur. Visually detected areas of 18F-FDG-PET/CT hypometabolism were correlated with clinical, MRI and VEM findings. RESULTS: Hypometabolism was detected in 102/119 (86%) 18FFDG- PET/CT scans. The pattern of hypometabolism in 73 patients with normal MRI was focal unilobar in 16/73 (22%), multilobar unilateral in 8/73 (11%), bilateral in 27/73 (37%) and global in 5/73 (7%) of patients; whilst 17/73 (23%) showed normal metabolism. In 46 patients with lesions on MRI, 18F-FDG-PET/CT showed concordant localisation and lateralization of the EF in 30/46 (65%) patients, and bilateral or widespread hypometabolism in the rest. Addition of 18FFDG PET/CT impacted decision making in 66/119 (55%) of patients; 24/73 with non-lesional and 30/46 patients with lesional epilepsies were recommended for surgery or further surgical work up, whilst surgery was not recommended in 11/46 patients with lesional epilepsy due to bilateral or widespread hypometabolism. 25 patients subsequently underwent epilepsy surgery, with 16/25 becoming seizure free following surgery. CONCLUSION: 18F-FDG-PET/CT has an added benefit for the localization and lateralization of EF, particularly in patients with normal or inconclusive MRI.

Features of post-radioiodine whole body scan in non-invasive Follicular Thyroid Neoplasm with papillary-like nuclear features (NIFTP).

Recently, encapsulated follicular variant of papillary thyroid carcinoma has been reclassified as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) to emphasize the benign nature of this entity. In our institution, we have assessed 455 patients treated with radioiodine ablation for differentiated thyroid carcinoma and 20 of them were retrospectively found to fulfill the new NIFTP criteria. There was no evidence of metastasis on post radioiodine whole body scans for NIFTP cases and these patients were in remission subsequently. The benign features of these patients' whole body scans and good clinical outcome following treatment further support NIFTP as a low risk thyroid neoplasm.

Effects of a novel light-curable material on odontoblastic differentiation of human dental pulp cells.

AIM: To assess the biological effects, including odontoblastic differentiation of a novel light-curable material (TheraCal), on human dental pulp cells (hDPCs). METHODOLOGY: The hDPCs were isolated from freshly extracted, caries-free third molars. Ten discs of TheraCal and MTA (8 mm in diameter and 3 mm in height) were incubated in α-minimum essential medium (α-MEM) and the supernatant collected. Viability of hDPCs in response to TheraCal and MTA was measured using the WST-1 assay. RT-PCR and real-time PCR were used to detect the gene expression of dentine sialophosphoprotein (DSPP) and dentine matrix protein-1 (DMP-1). ALP staining and Alizarin red S staining were used to evaluate the expression of alkaline phosphatase (ALP) and mineralization behaviour. One-way analysis of variance and Tukey's post hoc test were used to determine the statistically significant differences as a result of the variation in test materials (P < 0.05). RESULTS: The effects of TheraCal and MTA on cell viability were similar except at the highest concentration. The mRNA level of DSPP increased significantly in the MTA group relative to the control at day 1 and 3 (P < 0.05). Also, the mRNA level of DSPP increased significantly in the TheraCal group relative to the control at day 3 (P < 0.05). The increased mRNA level of DMP-1 was 2.5-fold and 2.3-fold each in the MTA and TheraCal groups relative to the control (P < 0.05). Cells exposed to MTA exhibited a 1.4-fold increase of ALP staining relative to control (P < 0.05). In the mineralization assay, increased calcium nodule formation was twofold and 1.3-fold each in the MTA and TheraCal groups compared to the control (P < 0.05). CONCLUSIONS: TheraCal and MTA had the ability to induce odontoblastic differentiation and mineralization of hDPCs.

Simvastatin inhibits the expression of inflammatory cytokines and cell adhesion molecules induced by LPS in human dental pulp cells.

AIM: To investigate the effect of simvastatin on lipopolysaccharide (LPS)-stimulated inflammatory cytokines, cell adhesion molecules and nuclear factor-κB (NF-κB) transcription factors in human dental pulp cells (HDPCs). METHODOLOGY: The effect of LPS and simvastatin on human dental pulp cell (HDPCs) viability was measured using a 3-[4, 5-dimethylthiazol-2-yl]-2, 5 diphenyltetrazolium bromide (MTT) assay. The expression of inflammatory cytokines and cell adhesion molecules was evaluated by reverse-transcription polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. NF-κB transcription factors were evaluated by Western blot analysis. Statistical analysis was performed with analysis of variance (anova). RESULTS: The viability of cells exposed to different concentrations of E. coli LPS, P. gingivalis LPS and simvastatin was not significantly different compared with that of control cells (P > 0.05). LPS significantly increased interleukin (IL)-1ß (P < 0.05) and IL-6 mRNA expression (P < 0.05) and vascular cell adhesion molecule-1 (VCAM-1) (P < 0.05) and intercellular adhesion molecule-1 (ICAM-1) protein expression (P < 0.05) in HDPCs. Treatment with simvastatin significantly attenuated LPS-stimulated production of IL-1ß, IL-6, VCAM-1 and ICAM-1 (P < 0.05). Treatment with simvastatin decreased LPS-induced expression of p65 and phosphorylation of IκB and also significantly decreased the phosphorylation of p65 and IκB in the cytoplasm and the level of p65 in the nucleus (P < 0.05). CONCLUSIONS: Simvastatin has a suppressing effect on LPS-induced inflammatory cytokine, cell adhesion molecules and NF-κB transcription factors in HDPCs. Therefore, simvastatin might be a useful candidate as a pulp-capping agent in vital pulp therapy.

Effect of Biodentine and Bioaggregate on odontoblastic differentiation via mitogen-activated protein kinase pathway in human dental pulp cells.

AIM: To compare the mineralization inductive capacity of Biodentine and Bioaggregate with Mineral trioxide aggregate (MTA) and to investigate possible signaling pathways of mineralization in human dental pulp cells (HDPCs). METHODOLOGY: Viability of HDPCs in response to Biodentine, Bioaggregate, and MTA was measured using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide. To investigate their potential to induce odontoblast differentiation, expression of dentine sialophosphoprotein (DSPP) and dentine matrix protein1 (DMP1) mRNA level was evaluated by RT-PCR. For the mineralized nodule assay, Alizarin red staining was performed. To determine the role of MAPK signaling in the odontoblastic differentiation of HDPCs, activated MAPKs were investigated by Western blot and the effect of MAPK inhibitor was examined by Alizarin red S staining. The results were statistically analysed using one-way anova and the Bonferroni test. RESULTS: The effects of MTA, Biodentine, and Bioaggregate on cell viability were similar. Biodentine and Bioaggregate enhanced DSPP and DMP1 mRNA expression compared to the control group, but to the same extent as MTA (P < 0.05). MTA, Biodentine, and Bioaggregate increased the area of calcified nodules compared to the control (P < 0.01). MTA, Biodentine, and Bioaggregate increased phosphorylation of extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal kinase (JNK). MAPK inhibitors attenuated mineralized nodule formation, which was increased by MTA, Biodentine, and Bioaggregate, respectively (P < 0.01). CONCLUSION: Biodentine and Bioaggregate stimulated odontoblastic differentiation and mineralization nodule formation by activating the MAPK pathway as did MTA. This suggests that the new materials could be useful for regenerative endodontic procedures.

The effective zone of botulinum toxin A injections in the sternocleidomastoid muscle.

PURPOSE: The aim of this study was to document the anatomical landmarks of the motor entry point (MEP) and the intramuscular motor point (IMP) of the sternocleidomastoid (SCM) muscle for effective botulinum toxin injections. MATERIALS AND METHODS: Thirty-five specimens from 20 adults bodies donated to science were investigated. The reference points were the mastoid process and the most medial point of the clavicle. RESULTS: The mean length of the reference line was 165.2 ± 12.8 mm. 97.0% of the total number of MEP in this study were located at 20-40 and 85.0% of the total number of the IMP was located at 20-70% from the mastoid process. The intersection with the great auricular nerve was located at 22%, it was 45% for the transverse cervical nerve and 28% for the external jugular vein. CONCLUSIONS: In clinical practice, the mass in patients with torticollis or cervical dystonia might be formed at the lower part or upper part of the SCM muscle. For a mass in the upper portion of the SCM muscle, the injection area using alcohol, phenol or botulinum toxin was determined to be 20-40%. However, to inject the area at 20-40%, ultrasound guidance is recommended because of the cervical cutaneous nerves and veins. For a mass in the lower portion of the SCM muscle, the injection area of botulinum toxin was 50-70%. These areas can be used with botulinum toxin injections or other agents for motor point blocking in patients with torticollis or cervical dystonia.

Anatomical localization of submandibular gland for botulinum toxin injection.

The aim of this study was to document the anatomical landmarks of the submandibular gland (SMG) for a botulinum toxin injection. Thirty-four SMGs from 20 cadavers were examined. The mean length of a reference line between the angle of the mandible and the gnathion was 94.8 ± 5.9 mm, the proximal and distal point of the SMG from the angle of the mandible was 10.6% (11.5 ± 3.5 mm) and 41.8% (40.9 ± 5.2 mm), respectively. The facial artery came out of the SMG at 11.6% (14.6 ± 3.4 mm) and the position of the intersection of the facial artery with the inferior border of the mandible was located at 24.4% (28.0 ± 5.5 mm) from the angle of the mandible. The shape of the SMG was generally triangular or irregular round on the anatomical position. The mean superior-inferior diameter, anterior-posterior diameter and medial-lateral diameter of the gland was 28.8 ± 4.1, 30.0 ± 6.1 and 15.1 ± 3.5 mm, respectively. The safety zone for the injection was 20-35% from the mandible angle on the inferior view and 1.5 cm below the inferior line of the mandible on the lateral view. In addition, the needle should be inserted to a depth of 2.0 cm from the skin surface on the inferior view. These results may assist in determining a accurate localization of injection sites for the SMG, particularly for injections without ultrasound guidance.

Effect of Tack Cure on Polymerization Shrinkage of Resin-based Luting Cements.

CLINICAL RELEVANCE: Self-cure after tack cure could result in a lower polymerization shrinkage in some resin-based luting cements, which is closely related to lower degree of cure.

Assessing the need for nuclear cardiology and other advanced cardiac imaging modalities in the developing world.

BACKGROUND: In 2005, 80% of cardiovascular disease (CVD) deaths occurred in low- to middle-income countries (i.e., developing nations). Cardiovascular imaging, such as myocardial perfusion SPECT, is one method that may be applied to detect and foster improved detection of at-risk patients. This document will review the availability and utilization for nuclear cardiology procedures worldwide and propose strategies to devise regional centers of excellence to achieve quality imaging around the world. METHODS: As a means to establish the current state of nuclear cardiology, International Atomic Energy Agency member and non-member states were queried as to annual utilization of nuclear cardiology procedures. Other sources for imaging statistics included data from medical societies (American Society of Nuclear Cardiology, European Society of Cardiology, and the European Association of Nuclear Medicine) and nuclear cardiology working groups within several nations. Utilization was calculated by dividing annual procedural volume by 2007 population statistics (/100,000) and categorized as high (>1,000/100,000), moderate-high (250-999/100,000), moderate (100-249/100,000), low-moderate (50-99/100,000) and low (<50/100,000). RESULTS: High nuclear cardiology utilization was reported in the United States, Canada, and Israel. Most Western European countries, Australia, and Japan reported moderate-high utilization. With the exception of Argentina, Brazil, Colombia and Uruguay, South America had low usage. This was also noted across Eastern Europe, Russia, and Asia. Utilization patterns generally mirrored each country's gross domestic product. However, nuclear cardiology utilization was higher for developing countries neighboring moderate-high "user" countries (e.g., Algeria and Egypt); perhaps the result of accessible high-quality training programs. CONCLUSIONS: Worldwide utilization patterns for nuclear cardiology vary substantially and may be influenced by physician access to training and education programs. Development of regional training centers of excellence can guide utilization of nuclear cardiology through the application of guideline- and appropriateness-driven testing, training, continuing education, and quality assurance programs aiding developing nations to confront the epidemics of CVD.

Imatinib mesylate (Gleevec) in advanced breast cancer-expressing C-Kit or PDGFR-beta: clinical activity and biological correlations.

BACKGROUND: Novel molecular therapies for metastatic breast cancer (MBC) are necessary to improve the dismal prognosis of this condition. Imatinib mesylate (Gleevec) inhibits several protein tyrosine kinases, including platelet-derived growth factor receptor (PDGFR) and c-kit, which are preferentially expressed in tumor cells. We tested the activity of imatinib mesylate in MBC with overexpression of PDGFR or c-kit. Additionally, we sought to determine the biological correlates and immunomodulatory effects. PATIENTS AND METHODS: Thirteen patients were treated with Imatinib administered orally at 400 mg p.o. b.i.d. (800 mg/day), until disease progression. All patients demonstrated PDGFR-beta overexpression and none showed c-kit expression. RESULTS: No objective responses were observed among the 13 patients treated in an intention-to-treat analysis. All patients experienced disease progression, with a median time to progression of 1.2 months. Twelve patients have died, and the median overall survival was 7.7 months. No patient had a serious adverse event. Imatinib therapy had no effect on the plasma levels of the angiogenesis-related cytokines, vascular endothelial growth factor, PDGF, b-fibroblast growth factor, and E-selectin. Immune studies showed imatinib inhibits interferon-gamma production by TCR-activated CD4(+) T cells. CONCLUSION: Imatinib as a single agent has no clinical activity in PDGFR-overexpressing MBC and has potential immunosuppressive effects.

Isolation of a gene required for programmed initiation of development by Aspergillus nidulans.

In contrast to many other cases in microbial development, Aspergillus nidulans conidiophore production initiates primarily as a programmed part of the life cycle rather than as a response to nutrient deprivation. Mutations in the acoD locus result in "fluffy" colonies that appear to grow faster than the wild type and proliferate as undifferentiated masses of vegetative cells. We show that unlike wild-type strains, acoD deletion mutants are unable to make conidiophores under optimal growth conditions but can be induced to conidiate when growth is nutritionally limited. The requirement for acoD in conidiophore development occurs prior to activation of brlA, a primary regulator of development. The acoD transcript is present both in vegetative hyphae prior to developmental induction and in developing cultures. However, the effects of acoD mutations are detectable only after developmental induction. We propose that acoD activity is primarily controlled at the posttranscriptional level and that it is required to direct developmentally specific changes that bring about growth inhibition and activation of brlA expression to result in conidiophore development.

Imatinib mesylate suppresses cytokine synthesis by activated CD4 T cells of patients with chronic myelogenous leukemia.

Although imatinib mesylate (IM) is highly effective at inducing complete cytogenetic remission in patients with chronic myelogenous leukemia (CML), it is known to suppress T-cell proliferation in vitro. As cytokines are required for T-cell proliferation, we investigated the effects of IM on cytokine synthesis by T cells of CML patients by assessing cytokine synthesis by activated CD4+ and CD8+ T cells in vitro. The activation of T cells in the whole blood of IM-treated patients (CML-IM) with Staphylococcus enterotoxin B resulted in significantly lower percentages of CD4+ T cells that synthesized interleukin 2 (P = 0.017), interferon-gamma (P = 0.010), and tumor necrosis factor-alpha (P = 0.009) than did the activated T cells of control subjects. The addition of exogenous IM to the cultures of peripheral blood mononuclear cells of CML-IM patients reduced Th1 cytokine synthesis by the CD4+ T cells. Furthermore, IM therapy at clinical doses suppressed the tyrosine phosphorylation of ZAP70. These findings suggest that inhibition of ZAP70 signaling pathway and suppression of Th1 cytokine synthesis by CD4+ T cells required the presence of IM at the time of T-cell activation through the T-cell receptor.

Characterization of the role of the FluG protein in asexual development of Aspergillus nidulans.

We showed previously that a DeltafluG mutation results in a block in Aspergillus nidulans asexual sporulation and that overexpression of fluG activates sporulation in liquid-submerged culture, a condition that does not normally support sporulation of wild-type strains. Here we demonstrate that the entire N-terminal region of FluG ( approximately 400 amino acids) can be deleted without affecting sporulation, indicating that FluG activity resides in the C-terminal half of the protein, which bears significant similarity with GSI-type glutamine synthetases. While FluG has no apparent role in glutamine biosynthesis, we propose that it has an enzymatic role in sporulation factor production. We also describe the isolation of dominant suppressors of DeltafluG(dsg) that should identify components acting downstream of FluG and thereby define the function of FluG in sporulation. The dsgA1 mutation also suppresses the developmental defects resulting from DeltaflbA and dominant activating fadA mutations, which both cause constitutive induction of the mycelial proliferation pathway. However, dsgA1 does not suppress the negative influence of these mutations on production of the aflatoxin precursor, sterigmatocystin, indicating that dsgA1 is specific for asexual development. Taken together, our studies define dsgA as a novel component of the asexual sporulation pathway.

Restoration of Th1 cytokine synthesis by T cells of patients with chronic myelogenous leukemia in cytogenetic and hematologic remission with interferon-alpha.

Chronic myelogenous leukemia (CML) is a disorder of the hematopoietic stem cell that results in malignant expansion of myeloid cells with a cytogenetic abnormality, the translocation between chromosomes 9 and 22 known as the Philadelphia chromosome. Treatment with IFN-alpha has proven to be an effective therapy, inducing cytogenetic remission in CML patients. However, it is unknown whether IFN-alpha can restore normal immune function for patients who achieve a complete cytogenetic remission. To address this question, we used a method of intracellular staining and flow cytometric analysis to ascribe the syntheses of Th1 or Th2 cytokines to T-cell subsets of patients in chronic, in accelerated, and in blast crisis phases as well as patients who had achieved a complete cytogenetic remission with IFN-alpha. We assessed the cytoplasmic synthesis of cytokine in phorbol ester (phorbol 12-myristate 13-acetate)-activated CD4+ and CD8+ T-cell subsets of 81 patients with various stages of CML and 21 normal controls. The percentages of CD4+ and CD8+ T cells from patients in chronic, in accelerated, and in blast crisis phases that synthesized Th1 cytokines interleukin (IL)-2, IFN-gamma, and tumor necrosis factor-alpha were significantly lower than those of remission patients and normal controls. Conversely, the percentages of CD4+ and CD8+ T cells of patients in chronic, in accelerated, and in blast crisis phases of CML preferentially synthesized the Th2 cytokine IL-10. Patients who achieved a durable complete cytogenetic remission for >2 years without maintenance IFN-alpha therapy restored their preference for a Th1 cytokine profile that is necessary for efficient cytotoxic T-cell function.

Induction of inflammatory cytokines in placental monocytes of gravidae infected with the human immunodeficiency virus type 1.

Placental mononuclear cells (PMC) are susceptible to infection with the human immunodeficiency virus (HIV). PMC secreted tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta), and IL-6 among other factors, which, in turn, regulate HIV replication in latently infected cells. We assessed the induction of these cytokines in PMC from HIV-infected (HIV+) and uninfected (control) gravidae following exposure to lipopolysaccharide (LPS), HIV lysate (iHIV), recombinant HIV env (GP160) and HIV gag (gag55), and synthetic HIV p17 (HGP30) antigens. In comparison to control PMC, HIV+ PMC constitutively secreted higher levels of IL-1beta and IL-6 and were refractory to stimulation by iHIV, GP160, gag55, and HGP30. Control PMC IL-1 beta levels were boosted by LPS; gag55 and HGP30 augmented IL-6 but not IL-1 beta. Both groups exhibited low basal TNF-alpha production that was augmented by LPS. HIV+ PMC exhibited higher constitutive levels of IL-1 beta, IL-6, and TNF-alpha gene transcription than control PMC. These levels could be further augmented by LPS, yet the incremental levels were lower than those obtained from PMC of uninfected women. The high basal constitutive secretion of cytokines by HIV+ PMC and their refractoriness to activation may reflect a virus-mediated dysregulation of cytokine expression culminating in compromised host defenses against secondary opportunistic infections associated with AIDS.

Simultaneous determination of seven sulfonamide residues in swine wastewater by high-performance liquid chromatography.

A HPLC-UV method was used for simultaneous determination of the residual sulfonamides in swine wastewater. Sulfonamides were extracted with ethyl acetate prior to chromatographic analysis. An ODS column was used for separation and UV detection was used to monitor the sulfonamides. Factors that affect the chromatographic behavior and the recovery have been studied. Calibration graphs were linear with very good correlation coefficients (r > 0.9999) from 0.05 to 10 micrograms/ml. The applicability of the method to the analysis of swine wastewater samples was demonstrated.

Induction of labyrinthitis ossificans after pneumococcal meningitis: an animal model.

Newly formed disorganized bone fills the open spaces within the otic capsule in various pathologic conditions, resulting in labyrinthitis ossificans. The pathologic mechanisms of this disease remain poorly understood. To better study the sequence of events and contributing mechanisms involved in labyrinthitis ossificans, an animal model was developed. Three groups of Mongolian gerbils received either an intralabyrinthine injection of normal saline solution (group 1) or Streptococcus pneumoniae polysaccharide capsule antigens (groups 2 and 3). The temporal bones were harvested after 3 months and serially sectioned. None of the eight control animals (group 1), which received intralabyrinthine injections of normal saline solution had any histologic changes in their temporal bones. Nine of the surviving 19 animals in groups 2 and 3 had fibrosis or evidence of early ossification. A fourth group of Mongolian gerbils received two intrathecal injections of live S. pneumoniae organisms. The temporal bones were harvested after 3 months and serially sectioned. Fourteen of the surviving 15 animals had fibrosis or ossification or both. This animal model will provide a method for study of the mechanisms of labyrinthitis ossificans.

Role of placental cytokines and inflammation in vertical transmission of HIV infection.

In light of new evidence suggesting that maternal human immunodeficiency virus (HIV) infection produces at least a three-fold increase in the number of early spontaneous abortions, it is important to search for factors that may predispose to fetal wastage. Immunological factors are thought to play an important role in permitting the HLA-disparate fetus to continue to term, despite powerful maternal immune forces capable of rejection. In the context of a heightened incidence of spontaneous abortion in HIV infection, evidence is now accumulating that implicates an imbalance in immune factors in contributing to this fetal loss. Soluble immune factors, such as cytokines, have been suggested as contributing agents to recurrent spontaneous abortions. Inflammatory cytokines-interleukin 1beta, interleukin 6 and tumor necrosis factor alpha-have been measured in isolated placental trophoblastic cells in HIV-infected and non-infected pregnant women in an attempt to explore this hypothesis. These inflammatory cytokines and their messenger RNAs were significantly elevated before and after stimulation in HIV-infected women, supporting the belief that HIV-infected women present their fetuses a milieu of imbalanced immune factors capable of contributing to immunological rejection. In addition, these elevated inflammatory cytokine levels may contribute to HIV disease progression in fetuses by virtue of activation of HIV gene transcription factors similar to what has been demonstrated in in vitro systems. We therefore propose that HIV infection in pregnant women produces an altered state of certain soluble immune factors, which in concert with other immune factor abnormalities, such as loss of immune selection in the fetal thymus, predisposes the fetus to advanced HIV infection and possible spontaneous abortion.

Transcriptional factor ATF6 is involved in odontoblastic differentiation.

ATF6 is an endoplasmic reticulum (ER) membrane-bound transcription factor that regulates various cellular functions. The purpose of this study was to investigate the role of ATF6 in odontoblast differentiation. Rat tooth germs were isolated, changes in gene expression were evaluated over time, and localization of ATF6 was determined by immunohistochemistry. Human dental pulp cells (HDPCs) were cultured with 50 µg/mL ascorbic acid and 5 mmol/L ß-glycerophosphate or 100 ng/mL bone morphogenetic protein 2 to induce differentiation. Translocation of ATF6 was observed by immunofluorescence and confocal microscopy. Overexpression of ATF6 was performed with an adenoviral vector. Matrix mineralization was evaluated by alizarin red staining. Immunoreactivity to anti-ATF6 was observed in the odontoblastic layer of the molar tooth germ, and expressions of ATF6, dentin sialophosphoprotein (DSPP) and dentin matrix protein 1 (DMP1) increased gradually during tooth germ development. When HDPCs were cultured in differentiation media, ATF6, DSPP, and DMP1 expression increased with the expression of unfolded protein response (UPR) markers, BiP and CHOP. Immunofluorescence results showed that ATF6 protein moved from cytoplasm to nucleus when cells were exposed to differentiation media. Notably, overexpression of ATF6 increased DSPP and DMP1 expression, alkaline phosphatase (ALP) activity, and matrix mineralization in HDPC cultures. Inhibition of ATF6 decreased ALP activity and mineralization. These results suggest that ER membrane-bound transcriptional factor ATF6 may be involved in odontoblastic differentiation.