Urinary Concentration Defect and Renal Glycosuria in Cyclosporine-treated Rats

Background@#Urinary concentration impairment is a major feature of cyclosporine nephrotoxicity. @*Methods@#We explored two possible mechanisms that may underlie cyclosporineinduced polyuria; water, and/or osmotic diuresis. Cyclosporine was subcutaneously injected to normal salt-fed Sprague-Dawley rats at a daily dose of 25mg/kg for 2 weeks (Experiment I) and 7.5mg/kg for 6 weeks (Experiment II). @*Results@#In Experiment I, cyclosporine treatment caused an increase in urine volume (2.7±0.5 vs. 10.3±1.13mL/d/100 g BW, p<0.001) and a decrease in urine osmolality (2,831±554 vs. 1,379±478mOsm/kg H2O, p<0.05). Aquaporin-2 (AQP2) protein expression decreased in cyclosporine-treated rat kidneys (cortex, 78±8%, p<0.05; medulla, 80±1%, p<0.05). Experiment II also showed that urine volume was increased by cyclosporine treatment (4.97±0.66 vs. 9.65±1.76mL/d/100 g BW, p<0.05). Whereas urine osmolality was not affected, urinary excretion of osmoles was increased (7.5±0.4 vs. 14.9±1.4mosmoles/d/100 g BW, p<0.005). Notably, urinary excretion of glucose increased in cyclosporine-treated rats (7±1 vs. 10,932±2,462 mg/d/100 g BW, p<0.005) without a significant elevation in plasma glucose. In both Experiment I and II, GLUT2 protein expression in the renal cortex was decreased by cyclosporine treatment (Experiment I, 55±6%, p<0.005; Experiment II, 88 ±3%, p<0.05). @*Conclusion@#Both water diuresis and osmotic diuresis are induced by cyclosporine nephrotoxicity. AQP2 and GLUT2 downregulation may underlie water and osmotic diuresis, respectively.

Urinary Concentration Defect and Renal Glycosuria in Cyclosporine-treated Rats

Background@#Urinary concentration impairment is a major feature of cyclosporine nephrotoxicity. @*Methods@#We explored two possible mechanisms that may underlie cyclosporineinduced polyuria; water, and/or osmotic diuresis. Cyclosporine was subcutaneously injected to normal salt-fed Sprague-Dawley rats at a daily dose of 25mg/kg for 2 weeks (Experiment I) and 7.5mg/kg for 6 weeks (Experiment II). @*Results@#In Experiment I, cyclosporine treatment caused an increase in urine volume (2.7±0.5 vs. 10.3±1.13mL/d/100 g BW, p<0.001) and a decrease in urine osmolality (2,831±554 vs. 1,379±478mOsm/kg H2O, p<0.05). Aquaporin-2 (AQP2) protein expression decreased in cyclosporine-treated rat kidneys (cortex, 78±8%, p<0.05; medulla, 80±1%, p<0.05). Experiment II also showed that urine volume was increased by cyclosporine treatment (4.97±0.66 vs. 9.65±1.76mL/d/100 g BW, p<0.05). Whereas urine osmolality was not affected, urinary excretion of osmoles was increased (7.5±0.4 vs. 14.9±1.4mosmoles/d/100 g BW, p<0.005). Notably, urinary excretion of glucose increased in cyclosporine-treated rats (7±1 vs. 10,932±2,462 mg/d/100 g BW, p<0.005) without a significant elevation in plasma glucose. In both Experiment I and II, GLUT2 protein expression in the renal cortex was decreased by cyclosporine treatment (Experiment I, 55±6%, p<0.005; Experiment II, 88 ±3%, p<0.05). @*Conclusion@#Both water diuresis and osmotic diuresis are induced by cyclosporine nephrotoxicity. AQP2 and GLUT2 downregulation may underlie water and osmotic diuresis, respectively.

Sick Sinus Syndrome Following Severe Hyponatremia Associated with Desmopressin Therapy / 대한내과학회지

Desmopressin diacetate arginine vasopressin (DDAVP) is a synthetic analogue of the arginine vasopressin that is widely used in the treatment of diabetes insipidus, nocturnal enuresis, and polyuria. Although it is generally well-tolerated, DDAVP can cause hyponatremia, especially in elderly patients. There are many reports of DDAVP-induced hyponatremia, but there has been only one case report in which sinus node dysfunction was caused by severe hyponatremia. Here we report a case of sick sinus syndrome that occurred during an episode of severe hyponatremia induced by chronic use of desmopressin in a 91-year-old man who had nocturnal enuresis.

A Case of Benign Fibrous Histiocytoma of the Nasal Dorsum

Benign fibrous histiocytoma is a mesenchymal tumor that has been described as a benign neoplasm composed of fibroblasts and histiocytes. The occurrence of this lesion of the head and neck has been rarely reported. We experienced a case of benign fibrous histiocytoma on the nasal dorsum in a 53-year-old female. During physical examination, we found 1x1-cm-sized bilateral mass on the nasal dorsum. Excision and Z-plasty were performed, and recurrence was not observed for 12 months after operation. We present this rare case with review of the clinical and pathological features.

A Case of Jacobson's Nerve Schwannoma Extending into the External Auditory Canal / 대한이비인후과학회지

Schwannomas are slow-growing, benign neurogenic tumors arising from schwann cells. Their localization in the external auditory canal and the middle ear has rarely been reported. The authors experienced a very rare case of Jacobson's nerve schwannoma that extended into the external auditory canal in a 55-year-old woman. The tumor eroded the wall of the cochlear promontory and exposed the membranous labyrinth. The jugular foramen and the wall of the ear canal were preserved without destruction. This report represents the first documented case of a Jacobson's nerve schwannoma, which involved the external auditory canal.

Genetic Characteristics and Phylogenetic Analysis of Influenza Type B Viruses Isolated from Nasopharyngeal Suction Samples of Korean Patients

To investigate the genetic characteristics of human influenza type B viruses circulating in Chungbuk province, Korea, we tested 510 clinical samples of nasopharyngeal suction from pediatric patients diagnosed with respiratory illness between June 2007 and June 2008. Twelve out of thirty-six isolates were identified as type B influenza virus by RT-PCR and sequencing analysis. Interestingly, genetic characterization of type B viruses isolated in this study revealed that all type B influenza viruses were the Yamagata lineages, a vaccine strains of southern hemisphere during 2007~2008, rather than the Victoria lineage of northern hemisphere during 2007~2008. Furthermore, there were a total of twelve unique mutations (HA: H40Y, D/G230S, V252M and K272R and NA: P3H, P/T/S42Q, N59S) occurred in our type B isolates. These results suggest that relative high prevalence of type B viruses in Korea during 2007~2008 season might be due to the wrong vaccine strains selection. Taken together, the results of this study demonstrate continuous evolutions of human type B viruses by antigenic drift and also highlight the need to closely monitoring of influenza viruses to aid the early detection of potentially pandemic strains as well as underscore the need for new therapeutics.

Significance of the Expression of Tumor Markers in Adenoid Cystic Carcinoma and Pleomorphic Adenoma of the Salivary Gland / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Salivary gland tumors are characterized by extreme histological diversity. Even within a single tumor, various histological patterns are observed. The same histological patterns are shared among various tumor types, regardless of the biological behavior, making diagnosis difficult. Although a great number of immunohistochemical studies of major salivary gland tumors have been published, their clinical and diagnostic implications are not fully apparent. We have performed basic immunohistochemical stains of pleomorphic adenoma (PA) and adenoid cystic carcinoma (ACC) to determine the diagnostic value of c-kit, Ki-67, glial fibrillary acidic protein (GFAP) and p53. MATERIALS AND METHOD: Paraffin-embedded tissue specimens from 48 cases, who were diagnosed as PA (n=31) and ACC (n=17) from 1993 to 2002, were immunohistochemically stained for c-kit, Ki-67, GFAP and p53. RESULTS: In the immunohistochemical stains of c-kit, Ki-67 and p53, there were no difference between PA and ACC. However, in the immunohistochemical stain of GFAP, there were difference in PA and ACC. GFAP was expressed in 74% of the PA and was not expressed in all cases of ACC. CONCLUSION: These data suggest that GFAP immunoreactivity could be helped in the occasional differential diagnostic dilemma of pleomorphic adenoma versus adenoid cystic carcinoma in salivary gland.

Clinical Study of Deep Neck Infection / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The incidence of deep neck infection has decreased after the introduction of antibiotics and improvement of oral hygiene, but it may still be lethal especially when life-threatening complications occur. The objective of this study is to clarify the presenting signs and symptoms, clinical course, microorganisms, and management of deep neck infections. SUBJECTS AND METHOD: We retrospectively reviewed the records of 134 patients who were diagnosed with deep neck infection and who received treatment at the Chosun University Hospital between 1996 and 2005 for the analysis of age and sex, distribution related to spaces involved, the location of cellulitis and abscess, the side of lesion, the symptoms and signs, the etiologic events, the associated conditions, the result of culture, and the treatments. Peritonsillar abscesses were excluded from this study. RESULTS: The parapharyngeal space and extended space were the most commonly involved space of deep neck infections, followed by submandibular space, retropharyngeal space, and Ludwig's angina. The most common pathogens found were Streptococcus, followed by Klebsiella and Staphylococcus. In diabetic patients, Klebsiella pneumoniae was the most common causative pathogen. Peptostreptococcus was the most common anaerobic pathogen. CONCLUSION: Initial management including trial of proper empirical antibiotics is important. According to the culture and antibiotic sensitivity test in this study, a combined therapy of amoxicillin/clavulanic acid and metronidazole is useful in polymicrobial deep neck infection.

The Significance of Connexin 26 Expression in Squamous Cell Lesions of the Larynx / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Gap junctional intercellular communication (GJIC) is a mechanism for direct cell to cell signalling and is mediated by gap junctions, which consist of transmembrane proteins called connexins (Cxs). The authors investigated the role of connexin 26 as a biomarker that helps diagnose laryngeal squamous cell lesions. SUBJECTS AND METHOD: Paraffin-embedded tissue specimens from 50 patients, who were diagnosed with laryngeal invasive squamous cell carcinoma (n=15), carcinoma in situ (n=10), dysplasia (n=15), and non-neoplastic epithelial hyperplasia (n=10) between 1993 and 2005, were immunohistochemically stained for connexin 26 protein. RESULTS: Intracytoplasmic positive expression of connexin 26 was found in 100% of invasive squamous cell carcinoma and in 20% of carcinoma in situ. However, in dysplasia and hyperplasia, there were no positive expressions. Moreover, the majority of intercellular or membranous staining tended to decline in dysplasia, carcinoma in situ, and squamous cell carcinoma. CONCLUSION: These results suggest that aberrant expression of connexin 26 in laryngeal squamous cell lesions can be associated with tumorigenesis and invasion. Further studies are needed to investigate these expressions of connexin 26 and that it may represent more aggressive pathology of the larynx.

A Case of Maxillary Venous Hemangioma with Invasion to Hard Palate and Nasal Cavity / 대한이비인후과학회지

Hemangiomas are common benign soft tissue tumors in the head and neck, but they occur infrequently in the sinonasal cavity. Capillary, cavernous, mixed, and venous types of hemangiomas have been described. Venous hemangiomas are less commonly seen and are composed of thickened blood vessels that can still be recognized as veins. Chief symptoms are recurrent epistaxis and nasal obstruction; if the tumor becomes large, it may cause adjacent bony erosion. Preoperative diagnosis of maxillary sinus hemangioma is important since these lesions can frequently cause a large amount of hemorrhage during surgery. We report a case of a 80-year-old woman with a huge tumor in the maxillary sinus and oral cavity that was histopathologically diagnosed as venous hemangioma.