Comparison of osseous healing after sagittal split ramus osteotomy and intraoral vertical ramus osteotomy.

The sagittal split ramus osteotomy (SSRO) is generally associated with greater postoperative stability than the intraoral vertical ramus osteotomy (IVRO); however, it entails a risk of inferior alveolar nerve damage. In contrast, IVRO has the disadvantages of slow postoperative osseous healing and projection of the antegonial notch, but inferior alveolar nerve damage is believed to be less likely. The purposes of this study were to compare the osseous healing processes associated with SSRO and IVRO and to investigate changes in mandibular width after IVRO in 29 patients undergoing mandibular setback. On computed tomography images, osseous healing was similar in patients undergoing SSRO and IVRO at 1year after surgery. Projection of the antegonial notch occurred after IVRO, but returned to the preoperative state within 1year. The results of the study indicate that IVRO is equivalent to SSRO with regard to both bone healing and morphological recovery of the mandible.

A prospective randomized trial of either famotidine or omeprazole for the prevention of bleeding after endoscopic mucosal resection and the healing of endoscopic mucosal resection-induced ulceration.

BACKGROUND: It has been reported that inhibitors of gastric acid secretion prevent bleeding after endoscopic mucosal resection for mucosal gastric neoplasm. However, uncertain whether an histamine2-receptor antagonist or proton-pump inhibitor is more effective. AIM: To evaluate prospectively the effectiveness of famotidine or omeprazole for ulcer management after endoscopic mucosal resection. METHODS: From July 2003 to October 2004, 57 patients were randomly assigned to famotidine or omeprazole for the management of endoscopic mucosal resection. Both drugs were given intravenously for the first 2 days, thereafter by mouth. The bleeding rates after endoscopic mucosal resection, the effects on the healing of endoscopic mucosal resection-induced ulceration, and cost-benefits were compared. RESULTS: Twenty-eight patients received famotidine and 29 received omeprazole. No significant difference was observed between the two groups in patient characteristics. The bleeding rates after endoscopic mucosal resection were not significantly different (18% vs. 14%) between the groups. Similarly, no differences were seen in the size of the endoscopic mucosal resection-induced ulceration at 1, 30 and 60 days after resection between groups. The total costs of anti-secretory agents demonstrated a significant cost-benefit to those treated with famotidine (10,420 yen vs. 17,782 yen). CONCLUSIONS: Famotidine is suggested as a better alternative to omeprazole for the management of endoscopic mucosal resection, as it showed a clear cost-benefit, and the healing results after endoscopic mucosal resection were similar for the two treatment strategies.

Topographic and laminar organization of the vagal gustatory system in the goldfish, Carassius auratus.

The large majority of intraoral taste buds in goldfish are located on the gill arches and on the palatal organ, a muscular organ situated on the roof of the mouth. These taste buds are innervated by branches of the vagus nerve which terminate in a laminated vagal lobe, itself being an enlargement of the special visceral sensory column of the medulla. The tracer horseradish peroxidase (HRP) was used to determine the connectivity of the various branches of the vagus nerve that innervate the oropharyngeal gustatory surfaces. The entire oral cavity is mapped onto the vagal lobe so that the anterior end of the palatal organ and the most anterior gill arch are represented anteriorly in the vagal lobe; progressively more posterior oral structures are represented progressively more posteriorly in the lobe. The medial part of the palatal organ and the opposing gill arch surface, i.e., the ventromedial portion, are represented ventrally in the vagal lobe. The dorsolateral portions of the palatal organ and gill arches are represented dorsomedially in the vagal lobe. The topographic representation of the oral structures is similar for both the motor and sensory systems. In addition to this overall topographic organization, the different oropharyngeal structures are represented differentially in the layers of the vagal lobe. Palatal organ inputs reach layers VI and IX while gill arch inputs terminate in layers II, IV, and IX. The overall organization of the vagal lobe suggests a highly organized reflex system which is involved in the separation of food from substrate, especially during bottom feeding.

In vivo release of cisplatin from a needle-type copolymer formulation implanted in rat kidney.

Cisplatin, cis-dichlorodiamine platinum (II), was incorporated in a needle-type copolymer formulation (0.8 mm diameter, 6 mm long) by radiation-induced polymerization. The copolymer used was copoly(diethylene glycol dimethacrylate/polyethylene glycol #600 dimethacrylate, 80/20 vol%). This copolymer, containing 6 mg of cisplatin, was implanted into the kidney of adult male Wistar rats (420 +/- 20 g). A total of 70 d was required for 100% release of cisplatin in vivo. The kidney tissue surrounding the formulation was strongly necrotized by the action of cisplatin. Two layers of necrosis could be distinguished: necrotic tissue surrounding the formulation and necrobiotic tissue surrounding the necrotic tissue. The amount of necrotic tissue changed markedly over time, but no change was apparent in the amount of necrobiotic tissue. The maximal amounts of necrotized tissue were observed 14 d after implantation: 3100 microns and 600 microns thick for the necrotic and necrobiotic tissues, respectively.

Measurement of somatostatin release in rat brain by microdialysis.

We determined the most suitable conditions for measuring the somatostatin (SRIF) level by brain microdialysis and investigated its release from the hypothalamus. The relative recovery rate of SRIF was 8.4 +/- 0.5% (mean +/- SE) using a polycarbonate (PC) membrane with the push-pull method at a flow rate of 2 microliters/min. Using tubes with an internal diameter of 0.28 mm and lengths of 5, 25, 50 and 100 cm, the relative recovery rates using a PC membrane with the push method were 8.2 +/- 0.5%, 7.3 +/- 0.6%, 6.2 +/- 0.5% and 4.1 +/- 0.6%, respectively. When using tubes with an internal diameter of 0.1 mm and lengths of 5, 25, 50 and 100 cm, the relative recovery rates were 7.3 +/- 0.7%, 5.6 +/- 1.0%, 3.5 +/- 1.1% and 1.4 +/- 0.7%, respectively. The relative recovery rate was 5.2 +/- 0.5% with a polysulfone (PS-F, Fresenius) membrane, 4.5 +/- 0.4% with a PS-H (Hospal) membrane, 2.6 +/- 0.2% with an ethylenevinyl alcohol membrane (EVAL), 5.1 +/- 0.8% with a polyvinyl alcohol (PVA) membrane and 10.4 +/- 0.8% with a PS-K (Kaneka) membrane. With the push method, the extracellular SRIF level in rat pituitary was 42.8 +/- 1.8 pg/ml with a PC membrane, 23.1 +/- 2.9 pg/ml with an EVAL membrane at a flow rate of 2 microliters/min. With the push-pull method, it was 52.7 +/- 5.2 pg/ml using a PC membrane, 33.5 +/- 2.8 pg/ml using a PVA membrane and 54.4 +/- 3.2 pg/ml using a PS-K membrane.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of a combination of an antibacterial agent (ofloxacin) and a collagenase inhibitor (FN-439) on the healing of rat periapical lesions.

To investigate the effects of a combination of an antibacterial agent (ofloxacin) and a collagenase inhibitor (FN-439) in the root canal treatment of apical periodontitis, we studied the healing process of experimentally induced periapical lesions in rats by using immunohistochemical methods. With a topical application of a combination of ofloxacin and FN-439 following experimentally induced periapical lesions, both neutrophils and macrophages became significantly decreased in number, while active cementogenesis and extensive bone formation were seen in the periapical region. However, the use of ofloxacin alone also demonstrated a beneficial effect on periapical inflammation and healing. Therefore, it is suggested that ofloxacin is powerful against bacterial infection whether FN-439 is added. The only observed effect of a combination of ofloxacin and FN-439 is that it may more effectively inhibit osteoclastic bone resorption and activate the remodeling of the apical periodontal tissue if this combined medicament is used in a stage of active bone destruction characterized by high production of tissue collagenase.

Pathogenicity of nodavirus strains from striped jack Pseudocaranx dentex and Atlantic halibut Hippoglossus hippoglossus, studied by waterborne challenge of yolk-sac larvae of both teleost species.

The present study shows that differences in pathogenicity exist among fish nodavirus strains. In challenge trials, a Japanese strain (SJ93Nag) was highly virulent to larvae of the striped jack Pseudocaranx dentex but replication was not detected in larvae of Atlantic halibut Hippoglossus hippoglossus at 6 degrees C. Conversely, a Norwegian nodavirus strain (AH95NorA) that was highly virulent to the Atlantic halibut larvae did not replicate in striped jack larvae at 20 degrees C. Occurrence of the disease viral encephalopathy and retinopathy (VER) and cumulative mortality were significantly different in the 2 species when challenged with the 2 nodavirus strains. The presence of nodavirus in nervous tissue was monitored by immunohistochemical methods. Our results support the view that the genetic diversity among nodavirus strains reflects the existence of different viral phenotypes which may be adapted to infect different host species and/or for replicating at different temperatures. Fish nodaviruses represent surveyable pathogens well suited for studying the relation between viral genotypic and phenotypic properties such as host specificity, temperature optima, neuroinvasiveness and neurovirulence.

Radiographic evaluation of malignant fibrous histiocytoma affecting maxillary alveolar bone: a report of 2 cases.

OBJECTIVE: The purpose of this study was to evaluate the radiographic findings of malignant fibrous histiocytoma (MFH) and to discuss the contribution of these findings to a differentiation of MFH from other malignant tumors of the head and neck. STUDY DESIGN: Two cases of MFH of the maxillary sinus affecting the alveolar bone were evaluated radiographically and scintigraphically. RESULTS: We reported the following findings, which have only seldom been described: the presence of fairly well-demarcated bone destruction in the intraoral radiograph; the relatively smooth surface, uniform density, or no necrotic area of the tumor; in computed tomograph images showing the clear separation of the tumor from surrounding soft tissues; bone scintigraphs reflecting the periosteal reaction to tumor invasion; and lymphoscintigraphy of the metastatic lymph nodes. CONCLUSION: We evaluated the radiographic findings from 2 cases of MFH and describe findings that may aid in the differentiation of MFH. These radiographic features may help dentists differentiate MFH from other malignant tumors in the head and neck, although MFH is a rare disease and there are no radiographic findings that would indicate a specific diagnosis of MFH.

[Sex determination with a discriminant function analysis of deciduous teeth size in plaster models].

Plaster models of the teeth of 3-year-old Japanese children (96 males, 98 females) were used to record the crown length, crown width and crown thickness of 5 maxillary and 5 mandibular deciduous teeth (30 measurement values). These measurements were used to devise a number of sex determination formulae. A sex-determination formula using all 30 values was calculated. Furthermore, a number of practical formulae were derived from only the crown width and crown thickness values because the deciduous teeth wear in 4 years and older children rapidly progress, making the crown length measurement unreliable. These formulae were calculated for the maxillary teeth alone and mandibular teeth alone. The formulae based on only the crown width or thickness were also calculated for both maxillary and the mandibular teeth. A step-wise discriminant analysis was then used to ascertain the most reliable measurements and a practical formula subsequently devised. The results obtained were as follows: 1. The mean value for each measurement was greater in males than in females. 2. Significant differences in the values recorded were seen in 28 out of the 30 measurements taken. The measurement items not exhibiting these significant differences were the crown width of the maxillary lateral incisor and the crown thickness of the mandibular second molar. 3. The accuracy rates for the sex-determination analysis and the step-wise sex determination analysis calculated using all 30 values were 78.6% and 75.7%, respectively. 4. The accuracy ranges for the modified sex-determination formulae and the associated step-wise sex determination analyses were 70.6-78.4% and 67.0-76.8%, respectively.

Apatite-coated hyaluronan for bone regeneration.

The materials for the repair of bone defects require bone-inductive and bioabsorbable properties. We developed an apatite-coated hyaluronan (ACH) as a bone-regeneration material. To examine the initial behavior of osteoblast-like cells on ACH and its bone-inductive activity, we evaluated the proliferation and differentiation of osteoblast-like cells grown on ACH in vitro, and examined the effect of ACH on bone regeneration in vivo, comparing these with the effects of an atelocollagen sponge (AS). Hyaluronic acid, cross-linked by divinylsulfone, was freeze-dried and formed apatite in simulated body fluid. MC3T3-E1 osteoblast-like cells were cultured on ACH and AS. Alkaline phosphatase activity and osteocalcin mRNA expression increased more in cells grown on ACH than in those grown on AS. In vivo, round defects were created in rat crania and either filled with ACH or AS or left unfilled (sham group). After surgery, the ACH-treated group showed higher levels of bone formation than the other groups. These findings demonstrate that ACH is more effective than AS in promoting in vitro osteoblast-like cell differentiation and bone formation during the repair of bone defects in vivo, indicating that it may be of use in the treatment of various bone defects.

Thermosensitive gels incorporating polythioether units for the selective extraction of class b metal ions.

Novel temperature-responsive copolymers of N-isopropylacrylamide and monoaza-tetrathioether derivative, were synthesized for the selective extraction of soft metal ions such as silver(I), copper(I), gold(III) and palladium(II) ion. The ratio between N-isopropylacrylamide group and monoaza-tetrathioether group in the copolymer was determined. The ratio between N-isopropylacrylamide group and monoaza-tetrathioether group varied in the range of 66:1-187:1. Each lower critical solution temperature (LCST) of the polymer solution was determined spectrophotometrically by the relative absorbance change at 750 nm via temperature of the polymer solution. Metal ion extraction using the copolymer with appropriate counter anions such as picrate ion, nitrate or perchlorate ion was examined. Soft metal ions such as silver(I), copper(I), gold(III) and palladium(II) ion were extracted selectively into the solid polymer phase. The extraction efficiency of a metal ion such as silver ion increased as the increase of the ratio of the monoaza-tetrathioether group to N-isopropylacrylamide group in the polymer. The quantitative extraction of class b metal ions as well as the liquid-liquid extraction of metal ions with monoaza-tetrathioether molecule was performed.

Effect of honeycomb-patterned surface topography on the adhesion and signal transduction of porcine aortic endothelial cells.

Surface topography has vital roles in cellular response. Here, to investigate the mechanism behind cellular response to surface topography, we prepared honeycomb (HC)-patterned films from poly(epsilon-caprolactone) (PCL) with micropatterned surface topography by casting a polymer solution of water-immiscible solvent under high humidity. We characterized the adsorption of fibronectin (Fn) on the film using atomic force microscopy (AFM) and confocal laser scanning microscopy (CLSM). The response of porcine aortic endothelial cells (PAECs) to adsorbed Fn molecules onto HC-patterned films was observed by immunofluorescence labeling of vinculin and the actin fiber of PAECs cultured for 1 and 72 h in serum-free medium. The expression of focal adhesion kinase autophosphorylated at the tyrosine residue (pFAK) at 1 h culture was determined using an immunoprecipitation method. Fn adsorbed selectively around the pore edges to form ring-shaped aggregates. The immunostaining results revealed that PAECs adhered to the HC-patterned films at focal contact points localized around pore peripheries. These points correspond to adsorption sites of Fn. The expression of pFAK after 1 h on the HC-patterned film was 3 times higher than that on a corresponding flat film, indicating that the signaling mediated by the binding between Fn and the integrin receptor was more highly activated on the HC-patterned film. These results suggest that the cellular response to HC-patterned films (e.g., adhesion pattern and phosphorylation of FAK) originates from the regularly aligned adsorption pattern of Fn determined by the pore structure of the film.

Relationship between enantioselectivity of alternative molecularly imprinted polymeric membranes and species of amino acid residues composing chiral recognition sites.

Molecularly imprinted polymeric membranes with tetrapeptide residue H-Asp(OcHex)-Asp(OcHex)-Asp(OcHex)-Asp(OcHex)-CH2- (DDDD) or H-Glu(OBzl)-Glu(OBzl)-Glu(OBzl)-Glu(OBzl)-CH2- (EEEE) were prepared during membrane preparation (casting) processing in the presence of print molecules. The Boc-L-Trp imprinted polymeric membranes thus obtained showed adsorption selectivity toward Ac-L-Trp from its racemic mixtures. From adsorption isotherms of Ac-Trp, the chiral recognition site, that had been formed by the presence of print molecules in the membrane preparation process, exclusively recognized Ac-L-Trp that possessed the same configuration of the print molecule. The affinity constants between chiral recognition sites in the membrane and Ac-L-Trp was determined to be 1.00 x 10(4) mol(-1) dm3 and 1.08 x 10(4) mol(-1) dm3 for the DDDD and EEEE membranes, respectively. Enantioselective electrodialysis could be attained by applying an optimum potential difference to give permselectivity, with a value close to its adsorption selectivity.

Polymer blend implant for ocular delivery of fluorometholone.

Ocular implants containing fluorometholone (FLM) were prepared using blends of poly (DL-lactic acid) (PLA) and polyvinyl pyrrolidone (PVP). The effect of the fraction of PVP content on the release of FLM from the implant was investigated in vitro. The drug was released from the device by approximately following first order kinetics within the period of 40 d. The release rate gradually increased with an increase in the PVP content. The in vivo study after implantation in the anterior chamber of rabbit eyes indicated that the PLA-PVP implant showed a good correlation between the in vitro and in vivo release of FLM. The present polymer blend implant demonstrated a constant level of FLM in the aqueous humor for one month.

Surface structural change of bioactive inorganic filler-resin composite cement in simulated body fluid: effect of resin.

Recently much attention has been paid to bioactive filler-resin composite cements because they can solidify in a few minutes to give high mechanical strengths and they can bond to living bone. In this study the dependence on resin of apatite-forming ability in simulated body fluid (SBF) was investigated for the composite cements of bioactive CaO-SiO2-P2O5-CaF2 glass with polymethyl methacrylate (PMMA) or bisphenol-a-glycidyl methacrylate/triethyleneglycol (Bis-GMA/TEGDMA) resin. The PMMA-containing composite cement did not show the apatite-forming ability in SBF because the reaction of the glass grains with SBF was inhibited due to the complete covering of the grains with PMMA. To the contrary, the Bis-GMA/TEGDMA-containing cement exhibited high apatite-forming ability in SBF; these monomers significantly dissolved from the composite surface into SBF, causing a direct exposure of the glass grains to SBF to convert into silica gel. It is assumed that thus formed silica gels, and the silicate ions that were dissolved and adsorbed onto the composite surface, induced the apatite nucleation between the spaces of the glass grains and on the composite surface, respectively. A continuous bone-like apatite layer was formed on the top surface of the glass-Bis-GMA/TEGDMA composite cement in a short period.

Effects of liposome size on penetration of dl-tocopherol acetate into skin.

Liposomes were prepared from hydrogenated lecithin (H-PC) by sonication (S) or injection (I) of H-PC dissolved in ethanol containing dl-tocopherol acetate (VEA). The effects of liposomes on the dermal absorption of VEA were studied. The particle diameter of S-liposomes was smaller than that of I-liposomes. The penetration of liposomal H-PC into the skin was much higher for S-liposomes than for I-liposomes 30 min after application to the arms of healthy human volunteers and also to hairless rat back skin. The penetration of 14C-VEA into hairless rat back skin was higher from the liposomes than from free VEA, and the 14C-VEA penetration was higher from S-liposomes than from I-liposomes. 3H-Dipalmitoylphosphatidylcholine and 14C-VEA, which had been entrapped in liposomes, were not detected in plasma. H-PC inhibited the peroxidation of skin lipids. H-PC enhanced the penetration of VEA into the skin, but the degree of enhancement depended on the size of the liposomes, indicating that this liposomal characteristic was an important factor in dermal absorption and/or penetration.

Intravitreous delivery of dexamethasone sodium m-sulfobenzoate from poly(DL-lactic acid) implants.

Biodegradable intravitreal rod-shaped implants containing dexamethasone sodium m-sulfobenzoate (DMSB) were prepared from blends of poly(DL-lactic acid) (PLA) with number-average molecular weight 2000 (PLA2000) and 4000 (PLA4000). The effect of the fraction of PLA2000 on the release of DMSB from the implant was investigated after implantation in the vitreous body of rabbit eyes. After the initial burst, the drug was released slowly from the blended PLA implants with a PLA2000 fraction of below 30 wt% in normal eyes within a period of 28 d. For the implants with a higher PLA2000 fraction of over 50 wt%, the drug was released following approximately first order kinetics. In the vitrectomized eyes, the release of DMSB from the PLA2000/PLA4000 (5/5) implant was 2.5 times more rapid than in normal eyes, and the clearance of drug was also appreciably accelerated as compared with that in normal eyes.

A rare case of intraosseous polymorphous low-grade adenocarcinoma (PLGA) of the maxilla.

A rare case of intraosseous, polymorphous low-grade adenocarcinoma (PLGA) of the maxilla is presented. The lesion appeared to be cystic radiographically and the only finding which suggested malignancy was an irregular cortical border.