Morphological changes in the inferior nasal passage associated with superior repositioning of the maxilla with/without horseshoe osteotomy or turbinectomy.

Superior repositioning of the maxilla during Le Fort I osteotomy (LFI) may narrow the inferior nasal passage. This retrospective study was performed to investigate morphological changes in the inferior nasal passage following LFI with/without additional procedures performed for nasal ventilation (horseshoe osteotomy or inferior turbinate partial resection). Three groups of patients were compared: those undergoing conventional LFI (Conv, 63 patients), LFI with horseshoe osteotomy (Hs, eight patients), and LFI with inferior turbinate partial resection (Turb, 21 patients). Coronal computed tomography images were used to evaluate the degree of stenosis of the inferior nasal passage. The soft tissue and bony tissue volumes in the inferior turbinate were also calculated three-dimensionally. The rate of obstruction of the inferior nasal passage postoperative was 65.9%, 50%, and 11.9% in the Conv, Hs, and Turb groups, respectively (Fisher's exact test, P < 0.001). Patients in the Turb group had significantly less nasal obstruction regardless of the pitch direction of the maxillary movement or volume of the bone in the inferior turbinate (all P < 0.001). In conclusion, for patients with high superior repositioning and well-developed bony tissue in the inferior turbinate, additional procedures are recommended to maintain the ventilation of the nasal passage postoperatively.

A study of unfavorable splits in the sagittal ramus osteotomy with a short lingual cut.

In the bilateral sagittal split osteotomy, a short lingual cut is made on the medial side of the ramus; however, in some cases, a true fracture occurs on the buccal side of the ramus. The purpose of this study was to evaluate the relationship between the splitting pattern of the mandible and the form of the mandible, the surgical technique used, and the postoperative occurrence of relapse after 'unfavorable' splits. The investigation examined 143 patients in whom a short lingual cut was attempted. The rate of unfavorable split was 14.7% (42/286). A strong correlation was observed between the reach of the lateral bone cut to the inferior border of the mandible and an unfavorable split. According to multivariate regression, the factors leading to an insufficient lateral bone cut were the degree of inward curvature of the ramus (P=0.001) and the position of the lateral bone cut (P=0.002). There was no significant difference in relapse between cases of unfavorable and normal splits. An unfavorable split does not affect the prognosis of the occlusion, but it is important to confirm the inward curvature of the ramus and set the position of the lateral bone cut adequately to avoid unfavorable splits.

Influence of the anatomical form of the posterior maxilla on the reliability of superior maxillary repositioning by Le Fort I osteotomy.

Certain patients with facial deformities require superior repositioning of the maxilla via Le Fort I osteotomy; however, the magnitude of superior repositioning of the maxilla is often less than expected. In this study, the correlation between the accuracy of superior repositioning of the maxilla and the anatomical form of the maxillary posterior region was examined. Seventy-five patients who underwent Le Fort I osteotomy without forward movement of the maxilla but with superior repositioning of the maxilla were included in this study. The bone volume around the descending palatine artery (DPA), the angle of the junction between the pterygoid process and the tuberosity, and the distance between the upper second molar and the pterygoid process were measured via three-dimensional analysis. A significant negative correlation (r=-0.566) was found between the bone volume around the DPA and the ratio of repositioning (actual movement divided by expected movement). It is possible that the superior repositioning of the maxilla expected prior to surgery was not sufficiently attained because of the large volume of bone around the DPA. The results of this study show that in some patients, superior repositioning was not achieved at the expected level because of bone interference attributable to the anatomical form of the maxillary posterior region.

Treatment of refractory non-union after maxillary osteotomy: A case report.

Maxillary non-union is a rare complication that occurs after an orthognathic surgery such as Le Fort I osteotomy. Here, we report a case of refractory non-union after maxillary osteotomy, which required a second surgery with bone graft. A 33-year-old man who had undergone bimaxillary osteotomy complained of an abnormal sensation in the right alar part about 1 year after the surgery. The patient was diagnosed as having maxillary non-union. Although surgical stabilization was performed using titanium plates, the non-union remained. The re-fusion surgery was performed about 3 years after the bimaxillary osteotomy with autologous bone graft using a biodegradable fixation system. At the 1-year follow up, the maxillary non-union was healed both clinically and radiographically. Re-fusion surgery using bone graft with biodegradable fixation might be an effective treatment option in cases of prolonged non-union that becomes evident after a long period following the initial maxillary osteotomy.

Effects of Y-24180, a receptor antagonist to platelet-activating factor, on allergic cutaneous eosinophilia in mice.

We examined the effects of Y-24180, a potent and long-acting antagonist to platelet-activating factor (PAF), on allergic cutaneous eosinophilia and cytokine production in the skin of mice. Mice sensitized actively with ovalbumin (OA) were challenged by an intradermal injection of OA solution. The number of inflammatory cells, including eosinophils and eosinophil peroxidase (EPO) activity reflecting eosinophil infiltration into the tissue increased in OA-challenged skin 12 hr after the challenge. The levels of interleukin-4 (IL-4) and IL-5 also increased significantly in the challenged skin 12 hr and 3-24 hr, respectively, but that of interferon-gamma (IFN-gamma) did not change. Then, we evaluated the effects of Y-24180, ketotifen, suplatast and prednisolone on the increase in EPO activity, IL-4 and IL-5. These drugs were orally administered once a day for 5 days beginning 4 days before the challenge. Y-24180 (10 mg/kg) and prednisolone (5 mg/kg) significantly suppressed these parameters. Suplatast did not affect EPO activity, but significantly decreased the levels of IL-4 and IL-5. Ketotifen had no effect on them. These results indicate that the inhibition of IL-4, IL-5 and PAF are required to suppress the cutaneous eosinophilia and Y-24180 contributes to the treatment of allergic cutaneous eosinophilia.

Aperture width of the osteomeatal complex as a predictor of successful treatment of odontogenic maxillary sinusitis.

Odontogenic maxillary sinusitis (OMS) is an inflammatory disease caused by the spread of dental inflammation into the sinus. The long-term administration of antibiotic medicine and/or treatment of the causative tooth are the usual initial treatments. These initial treatments are not always effective, and the reason is not well understood. The purpose of this study was to identify factors of significance that may contribute to the results of the initial treatment of OMS. Thirty-nine patients were studied, divided into two groups according to the results of initial treatment: effective or non-effective. The effective group comprised 20 patients who were cured by initial treatment. The non-effective group comprised 19 patients who required an additional operation. The duration of symptoms, spread into the other sinuses, aperture width of the osteomeatal complex (OMC) on the side of the maxillary sinus, and anatomical variations in the sinuses were compared between the groups. The only significant difference found was in the aperture width of the OMC, which was significantly narrower in the non-effective group than in the effective group. The aperture width of the OMC may be a significant predictor of the effectiveness of initial treatment of OMS.

Effect of Y-24180, a receptor antagonist to platelet-activating factor (PAF), on allergic cutaneous reactions in actively sensitized mice.

OBJECTIVE AND DESIGN: We examined the effect of Y-24180, a potent antagonist to platelet-activating factor (PAF), on allergic cutaneous reactions in actively sensitized mice. MATERIALS: Male BALB/c and BALB/c-nu/nu mice were used. TREATMENT: Y-24180, ketotifen fumarate (ketotifen), and suplatast tosilate (suplatast) were orally administered twice a day for 3 days beginning 2 days before an ovalbumin (OA) challenge. Hydrocortisone 17-butyrate (hydrocortisone) was applied topically to ear surface once a day for 3 days, beginning 2 days before the OA challenge. METHODS: Mice actively sensitized with OA were challenged by intradermally injecting OA into both ears. Ear thickness was measured with a dial thickness gauge. RESULTS: Increase in ear thickness, with peak responses at 1 h (immediate phase reaction, IPR) and 24 h (late phase reaction, LPR) after the challenge, were induced in actively sensitized BALB/c mice. The reactions were not induced in T cell-deficient BALB/c-nu/nu mice. Y-24180 suppressed both the IPR and LPR of BALB/c mice. Although suplatast suppressed the LPR, the IPR was not affected. Ketotifen suppressed the IPR, but not the LPR. Hydrocortisone suppressed both the IPR and LPR of BALB/c mice. Furthermore, Y-24180 in combination with hydrocortisone significantly enhanced the effect of hydrocortisone on both the reactions. CONCLUSIONS: Y-24180 was demonstrated not only to suppress the IPR and LPR, but also to show strong suppressive effects in combination with topical hydrocortisone. Therefore, Y-24180 is expected to contribute to the treatment of inflammatory skin diseases including atopic dermatitis.

[Effects of traxanox sodium on experimental nasal allergy].

The anti-allergic actions of traxanox sodium pentahydrate (traxanox) were examined using experimental allergic rhinitis models. Traxanox (10 and 30 mg/kg, p.o.), tranilast (30 and 100 mg/kg, p.o.) and disodium cromoglycate (DSCG, 3 and 10 mg/kg, i.v.) dose-dependently inhibited the increase of dye leakage in rats actively sensitized with dinitrophenol-coupled ascaris extract. Traxanox was about 4 times more potent than tranilast. In this test, the inhibitory activity of traxanox (30 mg/kg, p.o.) was not affected by predosing with the same dose for 7 days. In addition, traxanox (1-10 mg/kg, i.v.) inhibited the allergically induced increase in nasal resistance of guinea pigs actively sensitized with egg albumin, while tranilast (10 mg/kg, i.v.), DSCG (100 mg/kg, i.v.) and mepyramine (1 mg/kg, i.v.) had little effect. These results suggest that traxanox may be clinically effective in treating patients with nasal allergies.

Effect of Y-20811, a long-lasting thromboxane A2 synthetase inhibitor, on antigen-induced airway hyperresponsiveness in guinea pigs.

Effect of Y-20811 on airway hyperresponsiveness was studied in sensitized guinea pigs. Airway hyperresponsiveness to acetylcholine (ACh) reached maximum 7 h after antigen challenge in guinea pigs sensitized actively. Y-20811 (0.3-3 mg/kg) administered orally 3 h prior to challenge inhibited this airway hyperresponsiveness in a dose-dependent manner. Y-20811 (3 mg/kg) administered orally 4 h after antigen challenge also decreased the airway hyperresponsiveness. On the other hand, Y-20811 did not affect the bronchoconstriction induced by ACh, serotonin and histamine in nonsensitized guinea pigs. The number of eosinophils in bronchoalveolar lavage fluid in the guinea pig reached the peak 7 h after antigen challenge. Y-20811 had a tendency to decrease the number of total cells, macrophages and eosinophils in a dose-dependent manner. These results suggest that Y-20811 suppress the asthmatic mechanism which causes antigen-induced airway hyperresponsiveness.

[Mechanism of analgesic action of Y-23023, a new non-steroidal anti-inflammatory drug].

The analgesic mechanism of Y-23023, a new non-steroidal anti-inflammatory drug, was investigated in the writhing response induced by intraperitoneal injection of kaolin and captopril in mice. Y-23023 (0.1-1 mg/kg, p.o.) suppressed the writhing frequency in a dose-dependent manner. Y-23023 also significantly reduced the increased levels of prostaglandin (PG) and bradykinin (BK) in the peritoneal cavity. In contrast, indomethacin, diclofenac sodium, loxoprofen sodium and mefenamic acid inhibited the writhing response, but their efficacies were lower than that of Y-23023. The peritoneal PG levels were dose-dependently reduced to the same extent as Y-23023, whereas the BK levels were not. M1, an active metabolite of Y-23023, inhibited the cyclooxygenase from sheep vesicular gland in a concentration-dependent manner, and its potency was similar to that of indomethacin. These results suggest that in addition to the suppressive effect on PG production via inhibition of cyclooxygenase, the inhibitory effect on BK production is involved in the analgesic action of Y-23023, unlike indomethacin and diclofenac sodium.

[Effects of Y-20811, a specific thromboxane A2 synthetase inhibitor, on chemical mediator-induced bronchoconstriction in guinea pigs].

We investigated the effects of Y-20811 on chemical mediator-induced bronchoconstriction and the release of chemical mediators into lung perfusion fluid during arachidonic acid (AA)-induced bronchoconstriction in guinea pigs. Y-20811 (0.01-1 mg/kg, i.v.), like acetylsalicylic acid or indomethacin, dose-dependently suppressed arachidonic acid- and LTD4-induced bronchoconstriction, and it (1 mg/kg, i.v.) also inhibited PAF-induced bronchoconstriction in guinea pigs. However, at a dose of 1 mg/kg, i.v., it was inactive against the bronchoconstriction induced by histamine, serotonin and acetylcholine in guinea pigs. Y-20811 (0.3-10 mg/kg) administered orally also prevented the LTD4-induced bronchoconstriction in a dose-dependent manner. This protective effect of Y-20811 (10 mg/kg, p.o.) persisted for at least 24 hr. Y-20811 (10 mg/kg, p.o.) also inhibited antigen-induced bronchoconstriction in guinea pigs passively sensitized with anti-ovalbumin guinea pig serum and pretreated with mepyramine. In the perfused and ventilated guinea pig lungs, Y-20811 inhibited AA-induced bronchoconstriction, decreased the release of TXA2 (estimated as TXB2) and increased the release of PGE2 into the perfused lung fluid, significantly (TXB2 and PGE2 were measured by HPLC). Therefore, Y-20811 suppressed various stimulant-induced bronchoconstrictions through the decrease of TXA2 production and the increase of PGE2 production. Thus, Y-20811 should prove useful as an anti-asthmatic drug.

Effect of Y-24180, a long-acting antagonist to platelet-activating factor (PAF), on PAF-induced reactions: a relationship between the partial structure of the compound and its duration of the action.

(+/-)-4-(2-Chlorophenyl)-2-[2-(4-isobutylphenyl)ethyl]-6,9-dime thy l-6H- thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepine (Y-24180) is a platelet-activating factor (PAF) antagonist, being similar to WEB 2086. One of the structural differences between the two PAF antagonists is the presence of a methyl substituent in Y-24180 at the 6-position of its ring system. Orally administered Y-24180 and WEB 2086 both dose-dependently prevented PAF-induced airway hyperresponsiveness (ED50: 0.0010 and 0.019 mg/ kg, respectively) and bronchoconstriction (ED50: 0.0014 and 0.024 mg/kg, respectively) in guinea pigs. Against the bronchoconstriction, here, the inhibitory effect of Y-24180 was significantly more potent and longer acting than that of WEB 2086. On the other hand, Y-24180 (10 mg/kg, p.o.) showed insignificant effects on the bronchoconstriction induced by leukotriene D4, histamine, serotonin, acetylcholine, arachidonic acid, or bradykinin. In an in vitro test, Y-24180 and WEB 2086 inhibited the PAF-induced aggregation of the rabbit washed platelets in a concentration-dependent manner (IC50: 1.2 and 64 nmol/l, respectively). Compared with desmethyl-Y-24180 and WEB 2086, Y-24180 and methyl-WEB 2086, both of which have a methyl substituent on the 6-position of their thienodiazepine ring, exhibited a longer acting suppressive effect on PAF-induced bronchoconstriction and significantly more stable binding to the PAF receptor after the washing-out procedure of the test compounds from platelets. Therefore, the 6-methyl substituent should be responsible for the PAF receptor binding stability of Y-24180, namely, for its long-acting anti-PAF effects in vivo. These results indicate that Y-24180 possesses the specific and long-acting PAF antagonistic effects in the airway.

Suppressive effects of Y-24180, a receptor antagonist to platelet activating factor (PAF), on antigen-induced asthmatic responses in guinea pigs.

OBJECTIVE AND DESIGN: Effects of Y-24180 on antigen-induced asthmatic responses were evaluated in actively sensitized guinea pigs and the effects were compared with those of several anti-asthmatic drugs. MATERIALS: Male Hartley guinea pigs were used. TREATMENT: Guinea pigs were actively sensitized with ovalbumin and were pretreated with pyrilamine Y-24180 was orally administered to the animals 3 h and others were 1 h before the antigen challenge. METHODS: The airway hyperresponsiveness was measured according to the method of Konzett and Rössler with some modifications. The immediate asthmatic response (IAR) and late asthmatic response (LAR) were measured by the oscillation method. Inflammatory cells infiltrated into the lungs were counted after the bronchoalveolar lavage. RESULTS: Under oral administration before or after the challenge with antigen, Y-24180, OKY-046, and ONO-1078 suppressed the antigen-induced airway hyperresponsiveness. Moreover, Y-24180, ONO-1078, AA-2414, and theophylline suppressed both the IAR and LAR, but OKY-046 only suppressed the LAR. Among the test drugs, only Y-24180 and theophylline suppressed the antigen-induced accumulation of eosinophils in the bronchoalveolar lavage fluid. CONCLUSIONS: The data indicate practical participation of PAF in the development of antigen-induced asthmatic responses in animals, and usefulness of Y-24180 in the clinical treatment of asthma as well as other anti-asthmatic drugs.

Effects of Y-24180, a long-acting and potent antagonist to platelet-activating factor, on immediate asthmatic response in guinea pigs.

The effect of Y-24180, a potent antagonist to-platelet-activating factor (PAF), was evaluated on the antigen-induced immediate asthmatic response (IAR) in actively sensitized guinea pigs that were pretreated with an antihistaminic agent, pyrilamine. Then, the effect was compared with that of other antiasthmatic agents. In a dose-dependent manner, Y-24180 (0.01-1 mg/kg, p.o.) suppressed the IAR, and WEB 2086 (0.1-10 mg/kg, p.o.), another PAF antagonist, also suppressed IAR in the same fashion as Y-24180. In contrast, AA-2414 (1-100 mg/kg,p.o.), a thromboxane A2 (TXA2) antagonist, was effective only at the beginning of the IAR and ONO-1078 (1-100 mg/kg, p.o.), a peptide leukotriene (pLT) antagonist, was effective only in the latter period, OKY-046, a TXA2 synthetase inhibitor, showed no significant suppression of the IAR at doses up to 100 mg/kg. Thus, PAF antagonists were more effective than the other agents tested in the present model for IAR. In a subsequent test, Y-24180 (1 mg/kg, p.o.) was confirmed to enhance the suppressive effects of theophylline (10 and 30 mg/kg, p.o.), procaterol (0.1 and 1 microgram/kg, i.v.), OKY-046 (100 mg/kg, p.o.) and ONO-1078 (100 mg/kg, p.o.) on the IAR. A combination of three agents, namely Y-24180 with OKY-046 and ONO-1078, completely suppressed the IAR. The results demonstrate that Y-24180 not only suppresses the IAR, but also enhances the suppressive effect of other antiasthmatic agents. Therefore, Y-24180 would be a clinically promising drug for the treatment of bronchial asthma.

Effect of Y-24180, an antagonist at platelet-activating factor (PAF) receptors, on IgE-mediated cutaneous reactions in mice.

OBJECTIVE AND DESIGN: We examined the effect of Y-24180, a potent platelet-activating factor (PAF) antagonist, on IgE-mediated cutaneous reactions in mice. MATERIALS: Female BALB/c mice were used. TREATMENT: Drugs were orally administered 1 h before a dinitrofluorobenzene (DNFB) challenge or 1 h before and 12 h after the challenge. METHODS: Biphasic increase in ear thickness, with peak responses at 1 h (immediate phase reaction, IPR) and 24 h (late phase reaction, LPR) after the DNFB challenge, were induced in mice which had been passively sensitized with monoclonal anti-dinitrophenyl IgE antibody 24 h before the DNFB challenge. Ear thickness was measured with a dial thickness gauge. RESULTS: Y-24180, WEB2086, ketotifen, and suplatast suppressed the IPR. Y-24180 also suppressed the LPR when administered once at 10 mg/kg or twice at 1 to 10 mg/kg. WEB2086 suppressed the LPR only when administered twice. However, ketotifen and suplatast did not suppress the LPR even when administered twice. Single administration of prednisolone significantly suppressed both the IPR and LPR. CONCLUSIONS: These results indicate that PAF may be involved in the induction of biphasic cutaneous reactions mediated by IgE, and Y-24180 is more effective compared with WEB2086 in this model. It is possible that the difference in the effectiveness between Y-24180 and WEB2086 depends on the persistence of those activities.