Assessing age-related change in Japanese mental foramen opening direction using multidetector computed tomography

OBJECTIVE

The purpose of this study was to investigate how the opening direction of the mental foramen (MF) changes with age in a Japanese population using multi-detector computed tomography (MDCT).

METHODS

Post-mortem MDCT scans of 121 Japanese subjects (66 males and 55 females) were carried out where all subjects possessed at least twenty teeth, including molar teeth, in the upper and lower jaws. Two angles of the mental foramen opening were measured, namely the superior-inferior angle in the coronal plane and anterior-posterior angle in the transverse plane, on the CT reconstructed images. The associations between age and these two angles were evaluated using a multiple regression analysis.

RESULTS

For male subjects, the relationship between the superior-inferior angle and age was a quadratic curve (p < 0.001). This angle increased until the subject reached their early 50s and then the angle decreased with age. In the transverse plane, there was a linear relation between the anterior-posterior angle and age (p=0.002).It was noted also that the angle decreased with age. By contrast, however, no significant associations between the two angles and age for either measurement were noted for female subjects. This study demonstrated that the opening direction of the mental foramen changes with age in Japanese male subjects. By contrast this change in the opening direction of the mental foramen was not demonstrated in Japanese female subjects. In male subjects, the opening direction moves superiorly until the individual reaches their early 50s, and then moves inferiorly with advancing age. It also shifts from a posterior to an anterior position with age.

CONCLUSION

These observed change differ from the results of previous studies. The findings could be useful for forensic science as they demonstrate a change in the position of mental foramen in a sample of contemporaneous male Japanese subjects.

Maternal Separation Induces Orofacial Mechanical Allodynia in Adulthood

It is well known that exposure to maternal separation (MS) in early life causes plastic changes in the nervous system in adulthood, occasionally resulting in ubiquitous chronic pain. However, the pathogenic mechanisms of pain hypersensitivity remain unclear. Here, the authors examined the involvement of corticosterone in orofacial mechanical hypersensitivity induced by MS. To establish a rat model of MS, pups were placed in isolated cages 180 min/d and kept in a temperature-controlled environment at 22 ± 2 °C for 14 d. Mechanical allodynia in the whisker pad skin in adulthood was induced by MS and was significantly suppressed by successive postnatal subcutaneous administration of the glucocorticoid receptor antagonist mifepristone. Corticosterone levels were increased in the serum of MS rats, and successive postnatal administration of subcutaneous corticosterone to naive rats induced mechanical allodynia in the whisker pad skin. The number of P2X3 receptor-immunoreactive (P2X3R-IR) trigeminal ganglion (TG) neurons innervating the whisker pad skin was significantly increased in MS rats and decreased following subcutaneous administration of mifepristone. The number of P2X3R-IR TG neurons innervating the whisker pad skin was also significantly increased following successive postnatal administration of subcutaneous corticosterone in naive rats. Moreover, the mechanical allodynia was suppressed 30 min after administration of the P2X3R antagonist A317491 to the whisker pad skin in MS rats. These findings suggest that the increase in P2X3R-IR TG neurons innervating the whisker pad skin via enhanced neonatal corticosterone signaling by MS plays an important role in orofacial mechanical allodynia in adulthood.

Sensitization of TRPV1 by protein kinase C in rats with mono-iodoacetate-induced joint pain

OBJECTIVE

To assess the functional changes of Transient receptor potential vanilloid 1 (TRPV1) receptor and to clarify its mechanism in a rat mono-iodoacetate (MIA)-induced joint pain model (MIA rats), which has joint degeneration with cartilage loss similar to osteoarthritis.

METHODS

Sensitization of TRPV1 in MIA rats was assessed by transient spontaneous pain behavior induced by capsaicin injection in knee joints and electrophysiological changes of dorsal root ganglion (DRG) neurons innervating knee joints in response to capsaicin. Mechanisms of TRPV1 sensitization were analyzed by a newly developed sandwich enzyme-linked immunosorbent assay that detects phosphorylated TRPV1, followed by functional and expression analyses of protein kinase C (PKC) in vivo and in vitro, which involves TRPV1 phosphorylation.

RESULTS

Pain-related behavior induced by intra-articular injection of capsaicin was significantly increased in MIA rats compared with sham rats. In addition, capsaicin sensitivity, evaluated by capsaicin-induced inward currents, was significantly increased in DRG neurons of MIA rats. Protein levels of TRPV1 remained unchanged, but phosphorylated TRPV1 at Ser800 increased in DRG neurons of MIA rats. Phosphorylated-PKCɛ (p-PKCɛ) increased and co-localized with TRPV1 in DRG neurons of MIA rats. Capsaicin-induced pain-related behavior in MIA rats was inhibited by intra-articular pretreatment of the PKC inhibitor bisindolylmaleimide I. In addition, intra-articular injection of the PKC activator phorbol 12-myristate 13-acetate increased capsaicin-induced pain-related behavior in normal rats.

CONCLUSION

TRPV1 was sensitized at the knee joint and at DRG neurons of MIA rats through PKC activation. Thus, TRPV1 sensitization might be involved in chronic pain caused by osteoarthritis.

Expression of DOK1, 2, and 3 genes in HTLV-1-infected T cells

Human T-cell leukemia virus type 1 (HTLV-1) can cause an aggressive malignancy known as adult T-cell leukemia/lymphoma (ATLL). The Tax protein encoded by the pX region of the HTLV-1 genome appears to be a key element in the early stage of ATLL development. In this study, we examined the expression of the downstream of tyrosine kinase (DOK) family members DOK1, DOK2 and DOK3, recently reported to be tumor suppressors, in HTLV-1-transformed T cells (MT-2 and HUT-102) and TL-Om1 cells derived from ATLL leukemic cells. DOK2 and DOK3 expression was significantly reduced in MT-2, HUT-102, and TL-Om1 cells compared with their expression in uninfected T cells, and the expression of DOK3 was reduced by the induction of Tax expression in T cells.

A synthetic modular approach for modeling the role of the 3D microenvironment in tumor progression

Here, we demonstrate the flexibility of peptide-functionalized poly(ethylene glycol) (PEG) hydrogels for modeling tumor progression. The PEG hydrogels were formed using thiol-ene chemistry to incorporate a matrix metalloproteinase-degradable peptide crosslinker (KKCGGPQG↓IWGQGCKK) permissive to proteolytic remodeling and the adhesive CRGDS peptide ligand. Tumor cell function was investigated by culturing WM239A melanoma cells on PEG hydrogel surfaces or encapsulating cells within the hydrogels, and either as monocultures or indirect (non-contact) cocultures with primary human dermal fibroblasts (hDFs). WM239A cluster size and proliferation rate depended on the shear elastic modulus for cells cultured on PEG hydrogels, while growth was inhibited by coculture with hDFs regardless of hydrogel stiffness. Cluster size was also suppressed by hDFs for WM239A cells encapsulated in PEG hydrogels, which is consistent with cells seeded on top of hydrogels. Notably, encapsulated WM239A clusters and single cells adopted invasive phenotypes in the hDF coculture model, which included single cell and collective migration modes that resembled invasion from human melanoma patient-derived xenograft tumors encapsulated in equivalent PEG hydrogels. Our combined results demonstrate that peptide-functionalized PEG hydrogels provide a useful platform for investigating aspects of tumor progression in 2D and 3D microenvironments, including single cell migration, cluster growth and invasion.

Observation of Spin-Dependent Charge Symmetry Breaking in ΛN Interaction: Gamma-Ray Spectroscopy of _{Λ}^{4}He

The energy spacing between the spin-doublet bound state of _{Λ}^{4}He(1^{+},0^{+}) was determined to be 1406±2±2  keV, by measuring γ rays for the 1^{+}→0^{+} transition with a high efficiency germanium detector array in coincidence with the ^{4}He(K^{-},π^{-})_{Λ}^{4}He reaction at J-PARC. In comparison to the corresponding energy spacing in the mirror hypernucleus _{Λ}^{4}H, the present result clearly indicates the existence of charge symmetry breaking (CSB) in ΛN interaction. By combining the energy spacings with the known ground-state binding energies, it is also found that the CSB effect is large in the 0^{+} ground state but is vanishingly small in the 1^{+} excited state, demonstrating that the ΛN CSB interaction has spin dependence.

A novel method for assessing bladder-related pain reveals the involvement of nerve growth factor in pain associated with cyclophosphamide-induced chronic cystitis in mice

BACKGROUND

Pain is a prominent feature of interstitial cystitis/painful bladder syndrome (IC/PBS), but the underlying mechanisms are not fully understood. There is a lack of well-characterized research tools, such as pain evaluation methods and experimental animal models, for investigating non-ulcerative cystitis. We developed a novel method for evaluating bladder pain in mice with cyclophosphamide (CYP)-induced cystitis.

METHODS

Cystitis was produced by a single intraperitoneal injection of CYP (300 mg/kg) or repeated injections of CYP (150 mg/kg once daily for 4 days). Blunt stimulation with a cotton probe was applied to the abdominal region, and the thresholds for withdrawal responses were measured quantitatively using an anaesthesiometer.

RESULTS

The single injection of CYP provoked acute cystitis with severe bladder inflammation in mice. In these mice, we could detect an increased sensitivity to blunt stimulation, which was abolished by intravesical lidocaine. The stimulation induced phosphorylation of extracellular signal-regulated kinases in bladder-projecting sensory neurons. Chronic treatment with CYP produced persistent pain responses to the blunt stimulus. Although there were few signs of bladder inflammation in these mice, the concentration of nerve growth factor (NGF) was elevated in bladder tissue, and NGF antiserum inhibited the hypersensitivity.

CONCLUSIONS

The blunt probe method is useful for evaluating bladder pain signalling in mice, and revealed the involvement of an NGF-sensitive pain pathway in chronic cystitis pain. This assessment method may be useful for studying the pathophysiology of bladder pain and for developing therapeutic strategies for non-ulcerative IC/PBS in patients.

Roles of basophils and mast cells infiltrating the lung by multiple antigen challenges in asthmatic responses of mice

BACKGROUND AND PURPOSE

Mast cell hyperplasia has been observed in the lungs of mice with experimental asthma, but few reports have studied basophils. Here, we attempted to discriminate and quantify mast cells and basophils in the lungs in a murine asthma model, determine if both cells were increased by multiple antigen challenges and assess the roles of those cells in asthmatic responses.

EXPERIMENTAL APPROACH

Sensitized Balb/c mice were intratracheally challenged with ovalbumin four times. Mast cells and basophils in enzymatically digested lung tissue were detected by flow cytometry. An anti-FcεRI monoclonal antibody, MAR-1, was i.p. administered during the multiple challenges.

KEY RESULTS

The numbers of both mast cells (IgE(+) C-kit(+) ) and basophils (IgE(+) C-kit(-) CD49b(+) ) increased in the lungs after three challenges. Treatment with MAR-1 completely abolished the increases; however, a late-phase increase in specific airway resistance (sRaw), and airway eosinophilia and neutrophilia were not affected by the treatment, although the early-phase increase in sRaw was suppressed. MAR-1 reduced antigen-induced airway IL-4 production. Basophils infiltrating the lung clearly produced IL-4 after antigen stimulation in vitro; however, histamine and murine mast cell protease 1 were not increased in the serum after the challenge, indicating that mast cell activation was not evoked.

CONCLUSION AND IMPLICATIONS

Both mast cells and basophils infiltrated the lungs by multiple intratracheal antigen challenges in sensitized mice. Neither mast cells nor basophils were involved in late-phase airway obstruction, although early-phase obstruction was mediated by basophils. Targeting basophils in asthma therapy may be useful for an early asthmatic response.

Purification and Characterization of a DNA-dependent RNA Polymerase fromPseudomonas putida

DNA-dependent RNA polymerase (EC 2.7.7.6) was purified from Pseudomonas putida. The enzyme had the typical composition of beta',beta,alpha, and sigma subunits of eubacterial RNA polymerases. The molecular masses of the subunits were 156,000 Da, 151,000 Da, 87,000 Da, and 42,000 Da, respectively, as measured by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The NH2-terminal amino acid residues of the alpha subunit had a marked homology with those of the alpha subunit of Escherichia coli RNA polymerase. The enzyme activity was dependent on ribonucleoside triphosphates, Mg2+, and a DNA template, and was inhibited in vitro by rifampicin. The enzyme activity was maximal in the presence of 10 mM MgCl2. In an in vitro transcription assay using the tac promoter-controlled DNA as a template, the RNA polymerase of P. putida initiated transcription at the same site as that of E. coli.

High-energy spin and charge excitations in electron-doped copper oxide superconductors

The evolution of electronic (spin and charge) excitations upon carrier doping is an extremely important issue in superconducting layered cuprates and the knowledge of its asymmetry between electron- and hole-dopings is still fragmentary. Here we combine X-ray and neutron inelastic scattering measurements to track the doping dependence of both spin and charge excitations in electron-doped materials. Copper L3 resonant inelastic X-ray scattering spectra show that magnetic excitations shift to higher energy upon doping. Their dispersion becomes steeper near the magnetic zone centre and they deeply mix with charge excitations, indicating that electrons acquire a highly itinerant character in the doped metallic state. Moreover, above the magnetic excitations, an additional dispersing feature is observed near the Γ-point, and we ascribe it to particle-hole charge excitations. These properties are in stark contrast with the more localized spin excitations (paramagnons) recently observed in hole-doped compounds even at high doping levels.