Primary typical carcinoid tumour in the retromolar region with prominent squamous differentiation: a case report

Primary carcinoid tumours of the oral cavity are rare, with only one case of atypical carcinoid tumour reported in the literature. In this article, a case of primary typical carcinoid tumour in the retromolar region in a 46-year-old woman is described. Histologically, the tumour was characterized by submucosal proliferation of medium-sized monomorphous epithelioid cells with an organoid and nesting pattern of growth. Mitoses and necrosis were not found. Prominent squamous differentiation was present. Immunohistochemically, the tumour was diffuse positive for cytokeratin (CK) (AE1/AE3), CK7, p63, neurone-specific enolase, synaptophysin, and chromogranin. To the authors' knowledge, this is the first report of primary typical carcinoid tumour in the oral cavity.

Influence of season on some skin properties: winter vs. summer, as experienced by 354 Shanghaiese women of various ages

The facial skin of 354 women, aged 18-80, living in Shanghai, was investigated over two successive 6-month periods, summer and winter. Results from clinical assessments indicate that aging signs, such as wrinkling and sagging, are unaffected over such period. However, physical measurements revealed alterations in some functional criteria of the skin, such as sebum output, skin colour, melanin content of pigmented spots, skin hydration, all being increased during summer. The relationships between all criteria, as well as technical or applied inferences/consequences from this study, are discussed.

Single crystal study of competing rhombohedral and monoclinic order in lead zirconate titanate

Neutron diffraction data obtained on single crystals of PbZr(1-x)Ti(x)O3 with x=0.325 and x=0.460, which lie on the pseudorhombohedral side of the morphotropic phase boundary, suggest a coexistence of rhombohedral (R3m/R3c) and monoclinic (Cm) domains and that monoclinic order is enhanced by Ti substitution. A monoclinic phase with a doubled unit cell (Cc) is ruled out as the ground state.

Extra-articular diffuse tenosynovial giant cell tumour of the infratemporal fossa: report of a case and literature review

The authors describe a 34-year-old man who presented with an unapparent swelling on the right preauricular zygomatic region, with progressive limitation of mouth opening and slight temporomandibular joint pain. Based on fine-needle aspiration cytology and radiological investigations, the patient was diagnosed preoperatively as having a possible tenosynovial giant cell tumour (TGCT). Surgical treatment was effective and no local recurrence was observed. Histological and immunohistochemical examination diagnosed an extra-articular diffuse TGCT. The clinical features, histopathological characteristics, imaging modalities, diagnostic methods and treatment of TGCT are discussed and a review of the relevant literature is presented.

Total saponins of Panax ginseng (TSPG) promote erythroid differentiation of human CD34+ cells via EpoR-mediated JAK2/STAT5 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Total saponins of Panax ginseng (TSPG), main constituents extracted from Panax ginseng, a highly valued traditional Chinese medicine, have been shown to be an effective agent on hematopoiesis.

OBJECTIVE

To investigate the effect and mechanism underlying in which TSPG promote human CD34(+) hematopoietic stem and progenitor cells to differentiate into erythroid-lineage cells.

MATERIALS AND METHODS

The effect of TSPG on erythroid differentiation of purified CD34(+) cells derived from umbilical cord blood (UCB) was determined by methylcellulose assay system and colorimetry for hemoglobin content. The changes of EpoR expression in umbilical cord blood mononuclear cells (UCB-MNCs) and purified CD34(+) cells were detected with Western blotting and flow cytometry, respectively, and observed under laser scanning confocal microscope (LSCM). RT-PCR was performed to examine EpoR mRNA expression in CD34(+) cells. The effects of TSPG-pretreatment on Epo-induced JAK(2) and STAT(5) tyrosine phosphorylation were analyzed by immunoprecipitation.

RESULTS

The addition of TSPG (20-70 mg/L) increased the colony formation rate of BFU-E. TSPG (50 mg/L) alone used significantly increased the hemoglobin content, the addition of AG490 evidently reduced TSPG-induced elevation of hemoglobin content. TSPG increased the expression of EpoR on the surface membrane of CD34(+) cells but did not change the expression of EpoR in total UCB-MNCs. TSPG also increased the expression of EpoR mRNA in CD34(+) cells. TSPG markedly enhanced Epo-induced tyrosine phosphorylation of JAK(2) and STAT(5) in UCB-MNCs.

CONCLUSION

These findings suggest that TSPG may enhance the erythroid differentiation of hematopoietic stem and progenitor cells via Epo/EpoR-mediated JAK(2)/STAT(5) signaling pathway.

Pathological changes after the surgical creation of a vertical intracapsular condylar fracture

The aim of this study was to create in a sheep model an intracapsular oblique vertical split fracture, and observe the histopathological changes in the temporomandibular joint (TMJ) condylar head. In 10 sheep, the right TMJ was operated through the preauricular region. The anterior and posterior attachments of the disc were cut; an oblique vertical osteotomy was made from the lateral pole of the condyle to the medial side of condylar neck. The condylar fragment was pushed anteriorly, inferiorly and medially together with the disc. The non-operated left TMJ served as control. Two sheep were killed at 1 week and four at both 4 and 12 weeks. Computed tomography scans were taken and histopathological changes of the joint observed. There was severe bone erosion and a new bony outgrowth on the lateral side of the condylar stump and temporal bone. The joint spaces were filled with fibrous tissue, cartilage tissue and bone in the 4 and 12 weeks operated groups. These results show that an oblique vertical intracapsular fracture through the lateral condylar pole, combined with an anteriorly and medially displaced condylar fragment and disc and damaged lateral capsule, are likely to result in the pathological changes of osteoarthritis, and the progressive development of ankylosis in a sheep TMJ.

Endoscope-assisted reduction of long-standing condylar dislocation

Endoscopy is widely used in the diagnosis and treatment of temporomandibular joint disorders. This paper introduces arthro-endoscopy as a new method of treatment for temporomandibular joint dislocation. As this method is minimally invasive, it is suitable for medically compromised patients who cannot tolerate open surgery.

Role of NF-kappaB in TNF-alpha-induced COX-2 expression in synovial fibroblasts from human TMJ

In the temporomandibular joint (TMJ) synovium, cyclo-oxygenase-2 (COX-2) expression has been believed to be directly related to joint pain and synovitis. Here we investigated the role of Nuclear Factor kappaB (NF-kappaB) in the regulation of COX-2 expression in synovial fibroblasts from human TMJ induced by tumor necrosis factor-alpha (TNF-alpha). By reverse-transcriptase/polymerase chain-reaction (RT-PCR) and Western blotting analysis, TNF-alpha induced a dose- and time-dependent increase in COX-2 expression. Electrophoretic mobility shift assay (EMSA) revealed that transient NF-kappaB activation in the COX-2 promoter was triggered by TNF-alpha. In parallel with transient NF-kappaB activation, the rapid translocation of NF-kappaB, particularly the p65 subunit, from the cytoplasm into the nucleus was demonstrated. Pre-treatment with pyrolidine dithiocarbamate (PDTC), one of the NF-kappaB inhibitors, prevented binding to the COX-2 promoter and expression of COX-2 protein in response to TNF-alpha. These findings indicate that activation of NF-kappaB is responsible for TNF-alpha-induced COX-2 expression in synovial fibroblasts from the TMJ.

Ultrasonographic and arthrographic diagnoses of synovial chondromatosis

Synovial chondromatosis (SC) is rare in the temporomandibular joint (TMJ). Plain radiographs, CT, MRI and arthrography of the TMJ have been used for the diagnosis of SC. The purpose of this paper is to present ultrasonographic and arthrographic diagnoses of a case of SC of the TMJ.

Insulin and amino-acid regulation of mTOR signaling and kinase activity through the Rheb GTPase

Target of Rapamycin (TOR), a giant protein kinase expressed by all eucaryotic cells, controls cell size in response to nutrient signals. In metazoans, cell and organismal growth is controlled by nutrients and the insulin/insulin-like growth factor (IGF) system, and the understanding of how these inputs coordinately regulate TOR signaling has advanced greatly in the past 5 years. In single-cell eucaryotes and Caenorhabditis elegans, TOR is a dominant regulator of overall mRNA translation, whereas in higher metazoans, TOR controls the expression of a smaller fraction of mRNAs that is especially important to cell growth. TOR signals through two physically distinct multiprotein complexes, and the control of cell growth is mediated primarily by TOR complex 1 (TORC1), which contains the polypeptides raptor and LST8. Raptor is the substrate binding element of TORC1, and the ability of raptor to properly present substrates, such as the translational regulators 4E-BP and p70 S6 kinase, to the TOR catalytic domain is essential for their TOR-catalysed phosphorylation, and is inhibited by the Rapamycin/FKBP-12 complex. The dominant proximal regulator of TORC1 signaling and kinase activity is the ras-like small GTPase Rheb. Rheb binds directly to the mTOR catalytic domain, and Rheb-GTP enables TORC1 to attain an active configuration. Insulin/IGF enhances Rheb GTP charging through the ability of activated Akt to inhibit the Rheb-GTPase-activating function of the tuberous sclerosis heterodimer (TSC1/TSC2). Conversely, energy depletion reduces Rheb-GTP charging through the ability of the adenosine monophosphate-activated protein kinase to phosphorylate TSC2 and stimulate its Rheb-GTPase activating function, as well as by HIFalpha-mediated transcriptional responses that act upstream of the TSC1/2 complex. Amino-acid depletion inhibits TORC1 acting predominantly downstream of the TSC complex, by interfering with the ability of Rheb to bind to mTOR. The components of the insulin/IGF pathway to TORC1 are now well established, whereas the elements mediating the more ancient and functionally dominant input of amino acids remain largely unknown.

Electrosonographic characteristics of sounds from temporomandibular joint disc replacement

The purpose of this study was to investigate the waveform and electrosonographic characteristics of sounds emanating from internal derangement of the temporomandibular joint (TMJ). TMJ sounds were recorded from 10 joints of normal people (NP), 10 joints from patients with anterior disc displacement with reduction (DDR) and 20 joints from patients with anterior disc displacement without reduction (DDNR). The sounds were analyzed through fast Fourier transfer methods to observe their waveforms and electrosonographic characteristics. The observations were then used in differentially diagnosing internal derangement. Wave pattern and electrosonography (ESG) differed among the NP, DDR and DDNR groups. There was very little difference in frequency between the sounds from DDR and DDNR, but the amplitude of the DDR sounds was higher than those of DDNR and NP. The sensitivity and specificity of ESG diagnosis for DDR were 77.2% and 93.3%, respectively, while for DDNR they were 81.6% and 64.7%, respectively.

Clinical and radiological features of odontogenic ghost cell carcinoma: review of the literature and report of four new cases

OBJECTIVES

To analyse systematically the clinical and radiological features of odontogenic ghost cell carcinoma (OGCC).

METHODS

Clinical and radiological features of 22 OGCCs (4 new and 18 from the literature) were analysed.

RESULTS

There were 17 (77%) males and 5 (23%) females (male-to-female ratio of 3.4:1). Ages ranged from 13 years to 72 years (mean 36.7) with a peak in the fourth (40.9%) and fifth (27.3%) decades. The maxilla was involved in 68% and the mandible in 32%. Our study confirmed that OGCC is more prevalent in Asians (12/18) than in other racial groups. The mixed radiolucent and radiopaque lesion pattern was the most frequent (14/19) compared with radiolucent lesions (5/19). 89% (17/19) showed poorly defined borders and 11% (2/19) showed well defined borders. Root resorption was reported in 31% (6/19) of patients and tooth displacements in 21%.

CONCLUSIONS

OGCC demonstrates clinical and radiographic features of a malignant tumour with high recurrence.

TOR action in mammalian cells and in Caenorhabditis elegans

The p70 S6 kinase (p70 S6K) was the first signaling element in mammalian cells shown to be inhibited by rapamycin. The activity of the p70 S6K in mammalian cell is upregulated by extracellular amino acids (especially leucine) and by signals from receptor tyrosine kinases (RTKs), primarily through activation of the type 1A PI-3 kinase. The amino acid-/rapamycin-sensitive input and the PI-3 kinase input are co-dominant but largely independent, in that deletion of the amino-terminal and carboxy-terminal noncatalytic sequences flanking the p70 S6K catalytic domain renders the kinase insensitive to inhibition by both rapamycin and by withdrawal of amino acids, whereas this p70 S6K mutant remains responsive to activation by RTKs and to inhibition by wortmannin. At a molecular level, this dual control of p70 S6K activity is attributable to phosphorylation of the two p70 S6K sites: The Ptd Ins 3,4,5P3-dependent kinasel (PDK1) phosphorylates p70 S6K at a Thr on the activation loop, whereas mTOR phosphorylates a Thr located in a hydrophobic motif carboxyterminal to the catalytic domain. Together these two phosphorylations engender a strong, positively cooperative activation of p70 S6K, so that each is indispensable for physiologic regulation. Like RTKs, the p70 S6K appears early in metazoan evolution and comes to represent an important site at which the more ancient, nutrient-responsive TOR pathway converges with the RTK/PI-3 kinase pathway in the control of cell growth. Dual regulation of p70 S6K is seen in Drosophila; however, this convergence is not yet evident in Caenorhabditis elegans, wherein nutrient activation of the insulin receptor (InsR) pathway negatively regulates dauer development and longevity, whereas the TOR pathway regulates overall mRNA translation through effectors distinct from p70 S6K, as in yeast. The C. elegans TOR and InsR pathways show none of the cross- or convergent regulation seen in mammalian cells. The nature of the elements that couple nutrient sufficiency to TOR activity remain to be discovered, and the mechanisms by which RTKs influence TOR activity in mammalian cells require further study. One pathway for RTK control involves the tuberous sclerosis complex, which is absent in C. elegans, but of major importance in Drosophila and higher metazoans.

Inhibition of protein phosphatase-1 is linked to phosphorylation of p53 and apoptosis

p53 is a multifunctional protein and its activity can be modulated by phosphorylation and dephosphorylation. In this study, we sought to examine the notion that serine/threonine phosphatases (PP-1 and PP-2A) are active modulators of the p53-dependent apoptotic pathway. Exposure of neonatal rat cardiomyocytes to the established apoptotic agents, bafilomycin A1 (BAF) or staurosporine (STAU) induced apoptosis and caused a decrease in PP-1 activity of 35%. This response was restricted to apoptotic stimuli as treatment with phenylephrine neither decreased PP-1 and PP-2A activity nor induced DNA fragmentation in cardiomyocytes. The level of phosphorylated p53 was increased as a result of BAF or STAU-treatment. We further examined the effect of PP-1 inhibition on cardiomyocytes by the use of the phosphatase inhibitor, okadaic acid, and an antisense strategy. Okadaic acid (100 nM) resulted in a decrease in PP-1 activity of 45%, enhanced phosphorylation of p53, and stimulated apoptosis. Furthermore, overexpression of the antisense PP-1 catalytic subunit transcript caused a 44% decrease in expression of PP-1, with no change in the levels of the PP-2A catalytic subunit, and also evoked DNA fragmentation. Our data support the view that decreased activity of PP-1 is an important signaling event in the apoptotic process.

Evidence for estrogenic contamination of the MAPK inhibitor PD98059

PD98059 blocks phosphorylation and activation of MAPK proteins, ERK1 and ERK2. In the course of examining the effect of PD98059 on estrogen-induced transcription of reporter genes in a human breast cancer cell line and in yeast, we found that two of four different batches of PD98059 produced estrogenic effects in a dose-dependent manner. In a competitive binding assay, these preparations of PD98059 displaced radiolabeled estradiol from ER alpha. Furthermore, in the yeast assay, addition of a coactivator protein, AIB1, enhanced the transcriptional effect of PD98059, indicating that it induces receptor-coactivator interactions. Although concentrations of PD98059 required to activate ER alpha in these experimental systems are 10(4)- to 10(5) higher than the concentration of estradiol required to do the same, the concentrations required to block MAPK activation are well above those which would produce maximal estrogenic effects. Thus, when PD98059 is used in estrogen-responsive cells, contaminating estrogenic activity may confound interpretation of experimental results.