Audiological effect of bone-anchored hearing aid

The bone-anchored hearing aid (BAHA) has proved to be a valuable alternative to conventional air and bone conduction hearing aids for patients suffering from chronic otitis media or bilateral aural atresia. The BAHA gave better sound quality and greater comfort than conventional hearing aids (HAs), but only 1 study has been done in Japan. We implanted BAHAs in 6 hard-of-hearing patients in the last 2 years. One patient suffered skin problems around the abutment and used the BAHA only briefly. Free-field audiometry, the speech discrimination test (SDT), and the speech recognition test (SRT) were conducted in all subjects. They were evaluated either with the HA or BAHA. The SDT and SRT showed better hearing results in quiet for the BAHA than the conventional HA, but there was a minimum difference in SDT and SRT in noise. Subjects assessed the HA and BAHA using questionnaires. Subjects reported that the BAHA offers a number of important advantages, including greater cosmetic acceptability, improved speech intelligibility, and better sound quality.     

Malignant external otitis: treatment with prolonged usage of antibiotics and Burow's solution

Malignant external otitis is a severe infection of the external auditory canal, generally caused by Pseudomonas aeruginosa in elderly diabetics patients. We describe a case of malignant external otitis in a 63-year-old man with severe otalgia, purulent otorrhea and polypoid granulation of the external auditory canal. Local debridement, insulin treatment and 6-week intravenous antibiotic therapy with carbapemens were very effective and the granulation tissue disappeared completely. However, the patient readmitted for recurrent disease 3 weeks later, despite the oral and ear drop administration with new quinolone. No recurrence has been noted after 4-week additional treatment with intravenous carbapenems followed by 3-week treatment with Burow's solution as ear drops.     

Renal oncocytosis

Renal oncocytosis is a rare disorder in which numerous oncocytic nodules develop in the kidney. An additional case is reported here. The patient was a 51-year-old woman who had received hemodialysis for 27 years. Nineteen years previously she had developed a tumorous lesion in the right kidney, which had been diagnosed as oncocytoma with laparotomic biopsy. Recently the kidney was removed because of enlargement of the tumor. The renal parenchyma was entirely replaced with numerous brownish nodules. Histologically, the nodules were composed of nests of uniform oncocytic cells. Ultrastructurally, the oncocytic cells contained numerous mitochondria. Immunohistochemical features of the nodules were identical to those of sporadic oncocytomas, that is, immunophenotypes similar to the distal nephron and reactivity with antimitochondrial antigen. Based on these findings, the lesion was diagnosed as renal oncocytosis. It was not possible to determine whether the larger nodules should be diagnosed as oncocytoma or a part of oncocytosis. Additionally, the germ line mutation of the Birt-Hogg-Dubé (BHD) syndrome gene was examined using the genomic DNA obtained from the peripheral lymphocytes, which failed to show any gene alteration. Despite the rare occurrence pathologists and urologists should be aware of renal oncocytosis, as a precursor lesion of renal oncocytoma and chromophobe renal cell carcinoma.     

Gas‐Phase Assisted Surface Polymerization of Vinyl Monomers with Fe‐Based Initiating Systems

Summary: Gas‐phase assisted surface polymerization (GASP) of methyl methacrylate (MMA) and styrene (St) was investigated with Fe‐based radical initiating systems, FeCl₂/2,2′‐bipyridine (Bpy)/methyl α‐bromophenylacetate (MBPA), etc. GASP with these initiating systems proceeded to produce corresponding polymers on substrate surfaces. The resulting PMMA had very high PDI values, suggesting an uncontrolled reaction. In an attempt to control the GASP, polymerization with a simple initiating system, Fe(0)/MBPA, was examined on Fe(0)‐metal surfaces, resulting in significant polymerization activity to produce high‐molecular‐weight PMMA. The results of time‐course tests on GASP of MMA and St suggested that a change had taken place to produce physically controlled propagation sites on the Fe(0) powder surfaces.

GASP schemes with a simple initiating system Fe(0)/MBPA.     

Demonstration of long-range GABAergic connections distributed throughout the mouse neocortex

Gamma-aminobutyric acid (GABA)ergic neurons in the neocortex have been mainly regarded as interneurons and thought to provide local interactions. Recently, however, glutamate decarboxylase (GAD) immunocytochemistry combined with retrograde labeling experiments revealed the existence of GABAergic projection neurons in the neocortex. We further studied the network of GABAergic projection neurons in the neocortex by using GAD67-green fluorescent protein (GFP) knock-in mice for retrograde labeling and a novel neocortical GABAergic neuron labeling method for axon tracing. Many GFP-positive neurons were retrogradely labeled after Fast Blue injection into the primary somatosensory, motor and visual cortices. These neurons were labeled not only around the injection site, but also at a long distance from the injection site. Of the retrogradely labeled GABAergic neurons remote from the injection sites, the vast majority (91%) exhibited somatostatin immunoreactivity, and were preferentially distributed in layer II, layer VI and in the white matter. In addition, most of GABAergic projection neurons were positive for neuropeptide Y (82%) and neuronal nitric oxide synthase (71%). We confirmed the long-range projections by tracing GFP-labeled GABAergic neurons with axon branches traveled rostro-caudally and medio-laterally. Axon branches could be traced up to 2 mm. Some (n = 2 of 4) were shown to cross the areal boundaries. The GABAergic projection neurons preferentially received neocortical inputs. From these results, we conclude that GABAergic projection neurons are distributed throughout the neocortex and are part of a corticocortical network.     

A case-control analysis of intra-arterial urokinase thrombolysis in acute cardioembolic stroke

BACKGROUND: Intra-arterial urokinase (IA-UK) thrombolysis is frequently given in Japan to selected patients with acute cerebral artery occlusion. However, it is not clear whether or not IA-UK thrombolysis has an efficacy for acute stroke patients. The purpose of this study was to assess the effects of IA-UK thrombolysis in acute cardioembolic stroke patients, by performing a case-control analysis using data from Japan's Multicenter Stroke Investigator's Collaboration (J-MUSIC). METHODS: 16,922 acute ischemic stroke patients were enrolled into J-MUSIC. From these patients, we selected 91 patients (UK group) who met the following criteria: treatment with IA-UK; 20-75 years of age; cardioembolic stroke; presenting with a carotid stroke; admission within 4.5 h of symptom onset, and a National Institutes of Health Stroke Scale (NIHSS) score of 5-22 points on admission. A control group of 182 patients without IA-UK treatment and matched to the NIHSS score, gender, and age was chosen. We compared the modified Rankin scale (mRS) score at discharge and the mortality between the 2 groups. RESULTS: In both groups, the mean age was 65 +/- 8 years, and the median NIHSS score was 14. The mean interval between symptom onset and UK administration was 3.4 +/- 1.3 h, and the IA-UK dose was 392,000 +/- 200,000 units. The mRS score at discharge was lower in the UK group than in the control group (mean, SD, median; 2.8, 2.9, 2 in UK group vs. 3.3, 1.8, 4, in the control, respectively p = 0.031). A favorable outcome (mRS of 0-2) was more frequently observed in the UK group (50.5%) than in the control group (34.1%, p = 0.0124). No difference in the mortality rate was seen between the UK group (11.0%) and the control group (13.3%). As well, there was no difference in the length of hospital stay between the UK group (46 +/- 41 days, mean +/- SD) and the control group (42 +/- 42 days, mean +/- SD). CONCLUSIONS: IA-UK thrombolytic therapy may improve the outcome in hyperacute cardioembolic stroke patients.     

Dexamethasone inhibits maturation and alters function of monocyte-derived dendritic cells from cord blood

Critically ill infants are treated with dexamethasone (Dx) and other glucocorticoids to reduce inflammation and to promote lung and cardiac function. The neonatal immune system is immature, so neonatal dendritic cells (DCs) might be especially sensitive to glucocorticoid-mediated immunosuppression. To test this, we compared Dx treatment of monocyte-derived DCs from cord (CB) and adult blood (AB). Dx decreased CD1a levels on both AB and CB DCs. CB-treated cells also exhibited decreased expression of CD83 and increased expression of CD14, alterations not observed in AB DCs. Characteristic immature endocytic activity was sustained and enhanced in Dx-treated CB DCs, whereas AB DCs matured normally. Maintenance of endocytosis corresponded with CD14 expression. Dx markedly increased CB DC IL-10, a T cell helper 2 (Th2)-preferential cytokine, while reducing IL-12, a counterbalancing Th1 cytokine. AB DCs were also affected, but increases in IL-10 and decreases in IL-12 were more modest. Dx treatment also inhibited DC-induced T cell proliferation, but CB DCs were inhibited more. In short, neonatal DCs seemed to be especially sensitive to the immunosuppressive effects of Dx as indicated by altered phenotype, endocytic function, ability to stimulate T cells, and cytokine shift favoring Th2. These alterations in DC function are consistent with an increased risk for certain infections and atopic diseases.     

Acinic cell carcinoma of the parotid gland in a child

Acinic cell carcinoma of the parotid gland in children is an extremely rare occurrence. We present a 13-year-old girl with acinic cell carcinoma of the parotid gland. Removal of the superficial lobe of the parotid gland (superficial parotidectomy) was performed because the tumor was completely encapsulated by fibrous tissue and had not invaded the deep parotid gland. There is no clinical evidence of recurrence or metastasis 4 years after surgery. In our view, when tumors are completely encapsulated and do not adhere to the facial nerves, superficial parotidectomy is the best surgical treatment in children.     

Down's syndrome and esophageal achalasia: a rare but important clinical entity

We report a case of esophageal achalasia (EA) in Downȁ9s syndrome. A six-year-old girl with DS was referred from another hospital for further management of dysphagia and growth retardation (weight 16.3 kg, height 105.4 cm: both below −1.5 SD). Dysphagia commenced when she was one year old and gastroesophageal reflux (GER) was diagnosed when she was four. Routine investigations suggested EA or esophageal stenosis secondary to GER. While dissecting the esophago-gastric junction in preparation for a Heller-Dor esophagocardiomyotomy (HD-ECM), the crus of the diaphragm was noted to be narrowed, severely fibrosed and attached to the lower esophagus which was covered by dense scar tissue suggestive of an old esophageal perforation secondary to GER esophagitis. A Nissen fundoplication was performed, but dysphagia persisted postoperatively, and a narrowing 2 cm above the fundoplication wrap with proximal dilatation was found on repeated barium studies. At re-laparotomy, the fundoplication was unwrapped and HD-ECM performed. Eight months postoperatively, she is well with no recurrence. EA must be considered in any DS patient presenting with dysphagia.