The development of carbonate-containing apatite/collagen composite for osteoconductive apical barrier material

The current report describes the properties of a new apical barrier material formulated from carbonate-containing apatite (CAp) and collagen. CAp particles of around 50 nm were deposited on reconstituted collagen fibers. CAp/col with about 60 wt % CAp (corresponding to apatite content of bone) was obtained after 1 day of calcification. CAp content increased up to about 80 wt % in a 15-day calcification reaction. CAp/col was composed of fine calcified collagen fibers. The crystallinity and Ca/PO(4) ratio of CAp were comparable to those of bone apatite. The mixture of CAp/col and saline reached a pH of about 9. The optimum powder-to-liquid ratio (P/L) to set into a root canal was determined to be 1.2. Furthermore, the mixture (P/L = 1.2) condensed in a root canal was liquid permeable. Thus, the CAp/col was expected as an apical barrier material with osteoconductivity.     

Comparison of Outcomes of Single-Incision Laparoscopic and Open Appendectomy in Management of Uncomplicated and Complicated Appendicitis

Several reports have demonstrated the effectiveness and feasibility of single-incision laparoscopic appendectomy (SILA). We have introduced SILA including transumbilical laparoscopic-assisted appendectomy (TULAA) and pure single-incision laparoscopic appendectomy (PSILA). A total of 124 patients underwent SILA for acute appendicitis in our department. Our consecutive experiences with SILA are reviewed, and its outcomes including medical treatment cost are compared to open appendectomy (OA). In the SILA group, the mean length of the operation was 65.0 min. Five patients required an additional port insertion, and three patients required open conversion. The postoperative hospital stay was significantly shorter (P < 0.01); an abdominal drain was placed in significantly fewer cases (P < 0.01). There were no significant differences in the total cost medical treatment with OA (P = 0.48). In patients with complicated appendicitis, the hospital stay was significantly shorter in SILA groups. There were no significant differences in all operative outcomes between TULAA and PSILA. SILA represents an expeditious and reliable technique for appendicitis especially in complicated cases. Further assessment including multicenter prospective study is thought to be required to confirm this.     

Presumption of a suspect based on the skin fragment attached the rope

An eight-year-old girl (second-year of elementary school) was strangled in an irrigation canal near her house and was left unconscious. The body of a male who hanged himself to death was discovered on the next day. The hanging mark on the neck of the man and the ligature mark on the neck of the girl were caused by double nooses of a rope, the width of the rope mark was nearly the same, and similar Zwischenkammblutung (subcutaneous bleeding in the middle of the rope mark) was observed in both cases. Therefore, we evaluated whether the marks were caused by the same rope. As a result, the DNA type of the skin fragment (keratinized epithelial cells) attached to the rope used by the man to hang himself was identical to that of the girl. On the basis of this evidence, the man who hanged himself to death was presumed to be the suspect who strangled the girl.     

Identification of synaptic activity-dependent genes by exposure of cultured cortical neurons to tetrodotoxin followed by its withdrawal

Activity-dependent gene expression is one of the key mechanisms of synaptic plasticity that form the basis of higher order functions such as learning and memory. In the present study, we surveyed for activity-dependent genes by analyzing gene expression changes accompanying reversible inhibition of synaptic activity by tetrodotoxin (TTX) using two types of DNA microarrays; our focused oligo DNA microarray "Synaptoarray" and the commercially available high-density array. Cerebral cortical cells from E18 rat embryos were cultured for 14 days to ensure synaptogenesis, then treated with 1 muM TTX for 48 hr without detectable effect on cell viability. Synaptic density estimated by the amount of Synapsin I and Synaptotagmin I was decreased 21-24% by TTX treatment, but recovered to the control level 48 hr after TTX withdrawal. Comparison of gene expression profiles by competitive hybridization of fluorescently labeled cRNA from TTX-treated and control cells showed an overall downregulation of the genes on the Synaptoarray by TTX-treatment with different recovery rates after TTX withdrawal. With 16 representative genes, microarray data were validated by real-time PCR analysis. Genes most severely downregulated by TTX and upregulated above the control level at 5 hr after TTX withdrawal were munc13-1 (involved in docking and priming of synaptic vesicles) and Shank2 (involved in the postsynaptic scaffold). In addition, comprehensive screening at 5 hr after TTX withdrawal using high density arrays resulted in additional identification of Rgs2, a regulator of trimeric G-protein signaling, as an activity-dependent gene. These three genes are thus likely to be key factors in the regulation of synaptic plasticity. (c) 2007 Wiley-Liss, Inc.     

Pituitary adenylate cyclase-activating polypeptide (PACAP): a novel regulator of vasopressin-containing neurons

Pituitary adenylate cyclase-activating polypeptide (PACAP) was localized in nerve terminals that innervate arginine-vasopressin (AVP)-containing neurons in the rat hypothalamic supraoptic nucleus (SON). PACAP receptor (PACAPR) mRNA was expressed at high-levels in AVP-containing neurons in the SON, but at very low-levels in oxytocin-containing neurons. PACAPR-like immunoreactivity was found in SON and it was observed in the post-synaptic membranes as well as on the rough endoplasmic reticulum and cytoplasmic matrices in the magnocellular neurons. Doses of PACAP in the nanomolar range increased cytoplasmic Ca²⁺ concentrations ([Ca²⁺]_i) in AVP-containing neurons; the increase in [Ca²⁺]_i was inhibited by a protein kinase A blocker. These findings suggest that PACAP serves as a transmitter and/or modulator and the activation of PACAPR stimulates a cAMP-protein kinase A pathway which in turn evokes the Ca²⁺ signaling system. It is hypothesized that PACAP regulates the functions of AVP-containing neurons which participate in the control of plasma osmolarity and blood pressure.     

Expression of serine proteinase inhibitor PP5/TFPI-2/MSPI decreases the invasive potential of human choriocarcinoma cells in vitro and in vivo

OBJECTIVE: PP5/TFPI-2/MSPI is a Kunitz-type serine proteinase inhibitor with broad inhibitory spectra, abundantly produced by placenta and detected in the blood of pregnant women. Expression of PP5/TFPI-2/MSPI is exclusively detected in syncytiotrophoblasts of placenta, but is barely detectable in choriocarcinoma cells, a trophoblast-derived malignant tumor. Chromosome 7, in which the PP5/TFPI-2/MSPI gene is localized, is frequently lost in various types of tumors. We attempted to elucidate the relation between PP5/TFPI-2/MSPI expression and the malignant properties of choriocarcinoma cells. METHODS: Human choriocarcinoma cells, JAR, were transfected with either a human PP5/TFPI-2/MSPI expression vector or an empty vector, and stable clones were obtained. Messenger RNA expression, protein secretion/localization, growth rate, and plating efficiency were evaluated. In vitro migration and invasive activity were determined by transwell chamber experiments. In vivo tumor growth was evaluated by the subcutaneous injection of cells to nude mice and followed by histological examination. RESULTS: Expression of mRNA and protein of PP5/TFPI-2/MSPI were confirmed, and a high producing clone and a low producing clone were chosen for further analysis. The majority of secreted PP5/TFPI-2/MSPI protein was revealed to associate with the extracellular matrix. Expression of PP5/TFPI-2/MSPI did not affect the growth and migration of the tumor cells, but enhanced their plating efficiency. Its expression significantly inhibited invasion through the Matrigel. Invasive growth into the subcutaneous muscle layer was not evident in the nude mouse tumors of the PP5/TFPI-2/MSPI-expressing cells. CONCLUSION: PP5/TFPI-2/MSPI-expressing choriocarcinoma cells showed suppressed potential of invasion in vitro and in vivo. It is suggested that loss or suppression of PP5/TFPI-2/MSPI expression may result in the acquisition of invasiveness in choriocarcinoma cells.     

Cortical functional abnormality assessed by auditory-evoked magnetic fields and therapeutic approach in patients with chronic dizziness

A long-lasting dizzy sensation is a common complaint in elderly subjects. The pathogenesis and effective treatment of such chronic dizziness (CD), however, have not yet been fully elucidated because of lack of methods for evaluating this sensation. On the basis of assumption that CD may be attributable partly to cortical functional abnormality, we attempted to estimate the function of auditory cortex by measurements of auditory-evoked magnetic fields (AEFs). Magnetic field signals in the parieto-temporal cortex were evoked by 1000-Hz tone-burst with 90-dB normal hearing level sounds, and the highest-amplitude magnetic waveforms at approximately 100-ms (N100m) were analyzed as electrical current arrows in normal subjects (n=11), patients with CD (n=27) and patients with cerebral infarction but no dizzy sensation (n=9). In the normal subjects, the current arrows pointed to a nearly straight line with small directional distortion as indicated by a rotation-degree parameter, dI(rot) of 1.59+/-0.46. In 17 of 27 CD patients, the directions of current arrows were markedly distorted showing abnormally high dI(rot) values greater than 2.50 (the mean plus two standard deviations of normal values) and disclosed a clockwise or counter-clockwise rotation in either side or both sides of parieto-temporal cortex. In all the patients with cerebral infarction, the current arrows exhibited the similar pattern as the normal subjects. None of them exhibited abnormally high dI(rot) values. We hypothesized that the rotational abnormality may be caused by abnormal neuronal excitation, since non-evoked magnetic fields in temporal lobe epilepsy demonstrated the similar current rotational abnormality as reported previously. Seven CD patients were treated with anticonvulsants, and four showed remarkable amelioration of dizzy sensation. In all the four patients with symptomatic amelioration, the disappearance of rotational abnormality in AEFs or the tendency towards disappearance was observed following symptomatic amelioration. The results of the present study suggest that the auditory center may contribute to the maintenance of equilibrium, and its dysfunction may lead to the development of CD. AEFs measurements may make it possible to evaluate the functional abnormality of auditory center and may be useful for studying the pathophysiology and treatment of CD.