Kazuya Otsu

Effects of a novel nonantibiotic macrolide, EM900, on cytokine and mucin gene expression in a human airway epithelial cell line.

Background/Aims: Long-term macrolide therapy is an effective treatment for chronic sinusitis and diffuse panbronchiolitis. However, long-term use of macrolides may promote the growth of drug-resistant bacteria; therefore, development of macrolides with no antibacterial action is desirable. A new erythromycin (EM) derivative, (8R,9S)- 8,9-dihydro-6,9-epoxy-8,9-anhydropseudoerythromycin A (EM900), does not possess antibacterial action. Methods: To determine whether EM900 induced a clinically relevant anti-inflammatory response and repressed mucin gene expression in cells derived from human airway epithelia, we assessed the effects of EM900 on IL-1β-induced inflammatory cytokines in A549 cells and MUC5AC gene expression in HM3-MUC5AC cells. We also investigated the effects of EM900 on IL-1β-induced NF-ĸB activation. We performed reporter gene assays and quantitative PCR in A549 and HM3-MUC5AC cells. Results: Both EM and EM900 suppressed IL-1β-induced IL-8 expression in A549 cells. EM900 also suppressed IL-1β-induced IL-1β and TNF-α expression in A549 cells. EM900 inhibited IL-1β-induced MUC5AC expression in HM3-MUC5AC cells. Both EM and EM900 suppressed IL-1β-induced NF-ĸB activation in A549 cells. Conclusion: This study demonstrated that EM900 suppressed the induction of inflammatory cytokines and MUC5AC gene expression in cells derived from human airway epithelia, and our findings indicate that these effects may be mediated by the suppression of NF-ĸB activation.

Inhibition of Baroreflex Vagal Bradycardia by Selective Stimulation of Arterial Chemoreceptors in Rats

We reported recently that hypoxia inhibits baroreflex vagal bradycardia (BVB) in rats and that this inhibition persists following chemoreceptor denervation. However, since it is possible that hypoxia also affects the central processing of chemoreceptive input, the existence of chemoreceptor‐mediated inhibition of BVB cannot be ruled out. Therefore, we have studied whether selective chemoreceptor activation affects BVB in normoxic conditions. In pentobarbital‐urethane‐anaesthetized, succinylcholine‐immobilized, artificially ventilated rats, BVB was provoked by electrical stimulation of the aortic depressor nerve. Arterial chemoreceptors were selectively activated by intracarotid injection of a minute amount of sodium cyanide. Cyanide injection consistently increased blood pressure while changing heart rate variably. BVB was inhibited in a dose‐dependent manner. This inhibition, as well as changes in blood pressure and heart rate, was abolished following transection of the carotid sinus nerve (CSN) ipsilateral to the injection. Spinal cord transection at the C2 level did not affect the inhibition. On the other hand, intracarotid cyanide had no effect on bradycardia elicited by electrical stimulation of a peripheral cut end of the cervical vagus nerve. We conclude that chemoreceptor activation definitely inhibits BVB and that this inhibition is mediated by the CSN, and predominantly occurs in the central nervous system. The possibility is suggested that severe hypoxia suppresses not only BVB but also the chemoreceptor‐mediated inhibition of BVB, both via the direct, central action.

Aggressive Giant Cell Reparative Granuloma of the Nasal Cavity

Giant cell reparative granuloma (GCRG) is an uncommon and nonneoplastic reactive tumor that involves the maxilla and mandible in the region of the head and neck. It is rare in the nasal cavity, and it might be misdiagnosed. We reported a very aggressive GCRG with intracranial invasion, which was treated surgically via a combined approach of a lateral rhinotomy with a craniotomy by bilateral coronal incision. The pathology was consistent with GCRG. A short literature review about diagnosis, clinical behavior, and treatment of this tumor entity is given.

Anisotropy in lithium ion conduction in laminated thin films of montmorillonite nanosheets

Laminated thin films of lithium-ion-exchanged montmorillonite nanosheets were prepared, and their anisotropy in lithium ion conduction was investigated. For the films with 0.70 µm thickness, the lithium ion conductivities at 30 °C in the directions parallel and perpendicular to the film plane (σ//, σ⊥) were determined by alternative current impedance measurements and found to be 4.3 × 10−2 and 5.7 × 10−6 S cm−1, respectively. The dependence of σ⊥ on the nanosheet size for the films composed of nanosheets with different lateral sizes was also investigated. σ⊥ decreased as the lateral size of the nanosheets increased. A model for the lithium ion conduction path in the nanosheet-laminated films is proposed, and the dependence of conduction on the nanosheet size is discussed.

Endoscope-assisted intraoral removal of lingual thyroid

Lingual thyroid is a rare embryological anomaly and originates from failure of the thyroid gland to descend from the foramen caecum to its normal eutopic pretracheal site. The patient was a 34-year-oldfemale with hypothyroidism who complained of dyspnea feeling and an abnormal sensation in her throat. Imaging studies revealed a 35mm well-defined tumor on the midline of the tongue. Because replacement therapy of thyroid hormone was not effective, surgical therapy was chosen. In order to reduce morbidity and eliminate visible scarring, we performed lingual thyroidectomy via a transoral endoscope-assisted approach. There were no complications in the postoperative period. This case demonstrated that resection of a lingual thyroid by the transoral endoscope-assisted approach is technically feasible and safe, suggesting that it should be considered as the first choice in patients with symptomatic lingual thyroid.

術中 CT 撮影が有効であった舌迷入魚骨異物の1例

Fish bones as a foreign body are often present in the palatine tonsil and the base of the tongue. Such foreign bodies can often be diagnosed with inspection only. However, it is difficult to diagnose and extirpate a foreign body when it is buried in the oral/pharyngeal mucosa. We experienced a case of a fish bone foreign body buried in the tongue muscle layer. We report herein on the case of a 49-year-old man with a fish bone foreign body buried in his tongue. The patient had noticed a sore throat since eating a sea bream and was referred to our department. Visual inspection revealed no foreign body, but CT imaging revealed a fish bone in the tongue. We performed an emergency surgical exploration of tongue to locate the fish bone. Because the fish bone as a foreign body was unable to be confirmed by palpation, we identified the location of the fish bone by intraoperative CT. This is a rare case of a fish bone buried in the tongue muscle layer, and intraoperative CT was useful in identifying the positon of the foreign body.

Clinical Study of Cases of Laryngeal Cancer

A retrospective clinical study was conducted involving 143 patients with laryngeal cancer treated in our department between 1998 and 2006. The subjects consisted of 138 males and 5 females, with a ratio of 28:1. The mean age was 68.1 years old. The subsite of origin comprised 78 (54.5%) in the glottis, 61 (42.7%) in the supraglottis, and 4 (2.8%) in the subglottis. The clinical stage according to the 1997 UICC TMN classification system was I in 53 cases (37.1%), II in 34 (23.8%), III in 20 (14.0%), and IV in 36 (25.2%). The 5-year overall survival rate was 71.2% in the total cases, 84.4% in stage I, 89.6% in stage II, 51.2% in stage III, and 38.9% in stage IV. The disease-specific 5-year survival rate was 88.3% in the total cases, 75.5% in the supraglottic type, 98.1% in the glottic type, and 100% in the subglottic type. The preservation rate of the larynx at 5 years was 83.3% in T1, 56.5% in T2, and 0% in T3 and T4.

Clinical Statistical Observation of Laryngeal Carcinoma.

From 1990 through 1998, 143 patients with laryngeal cancer were treated in our department. Of the 143 patients, 94 had glottal, 43 had supraglottal, and 6 had subglottal cancer. The 5-year survival rate in patients with laryngeal cancer was 90.0% for stage I, 81.3% for stage II, 77.9% for stage III, and 42.6% for stage IV. The 5-year survival rate was 86.5% for glottal, 55.9% for supraglottal and 66.7% for subglottal cancer patients. The laryngeal preservation rate was 90.4% for stage I, 60.5% for stage II, 21.4% for stage III and 28.1% for stage IV.A loco-regional recurrence occurred in 24 of 143 patients (16.8%). The salvage rate for these patients was 45.8% (11/24). Six of 11 patients who died of primary disease and nodal failure (including 2 stomal recurrences) had supraglottic stage N carcinoma.In conclusion, laryngeal preservation surgery should be recommended in the early stages of cancer after radiation failure and local recurrence. It is recommended to dissect the anterior compartment including the delphian lymph node, pretracheal, and parathyroidal nodes bilaterally for patients with laryngeal tumors that have significant anterior subglottic extension, tumors arising in the subglottic region, or advanced tumors arising in any region, especially the supraglottis.