Biphasic modulation of NOS expression, protein and nitrite products by hydroxocobalamin underlies its protective effect in endotoxemic shock: downstream regulation of COX-2, IL-1ß, TNF-α, IL-6, and HMGB1 expression.

BACKGROUND: NOS/•NO inhibitors are potential therapeutics for sepsis, yet they increase clinical mortality. However, there has been no in vivo investigation of the (in vitro) •NO scavenger, cobalamin's (Cbl) endogenous effects on NOS/•NO/inflammatory mediators during the immune response to sepsis. METHODS: We used quantitative polymerase chain reaction (qPCR), ELISA, Western blot, and NOS Griess assays, in a C57BL/6 mouse, acute endotoxaemia model. RESULTS: During the immune response, pro-inflammatory phase, parenteral hydroxocobalamin (HOCbl) treatment partially inhibits hepatic, but not lung, iNOS mRNA and promotes lung eNOS mRNA, but attenuates the LPS hepatic rise in eNOS mRNA, whilst paradoxically promoting high iNOS/eNOS protein translation, but relatively moderate •NO production. HOCbl/NOS/•NO regulation is reciprocally associated with lower 4 h expression of TNF-α, IL-1ß, COX-2, and lower circulating TNF-α, but not IL-6. In resolution, 24 h after LPS, HOCbl completely abrogates a major late mediator of sepsis mortality, high mobility group box 1 (HMGB1) mRNA, inhibits iNOS mRNA, and attenuates LPS-induced hepatic inhibition of eNOS mRNA, whilst showing increased, but still moderate, NOS activity, relative to LPS only. experiments (LPS+D-Galactosamine) HOCbl afforded significant, dose-dependent protection in mice. CONCLUSIONS: HOCbl produces a complex, time- and organ-dependent, selective regulation of NOS/•NO during endotoxaemia, corollary regulation of downstream inflammatory mediators, and increased survival. This merits clinical evaluation.

The impact of endogenous annexin A1 on glucocorticoid control of inflammatory arthritis.

OBJECTIVES: To establish the role and effect of glucocorticoids and the endogenous annexin A1 (AnxA1) pathway in inflammatory arthritis. METHODS: Ankle joint mRNA and protein expression of AnxA1 and its receptors were analysed in naive and arthritic mice by real-time PCR and immunohistochemistry. Inflammatory arthritis was induced with the K/BxN arthritogenic serum in AnxA1(+/+) and AnxA1(-/-) mice; in some experiments, animals were treated with dexamethasone (Dex) or with human recombinant AnxA1 or a protease-resistant mutant (termed SuperAnxA1). Readouts were arthritic score, disease incidence, paw oedema and histopathology, together with pro-inflammatory gene expression. RESULTS: All elements of the AnxA1 pathway could be detected in naive joints, with augmentation during ongoing disease, due to the infiltration of immune cells. No difference in arthritis intensity of profile could be observed between AnxA1(+/+) and AnxA1(-/-) mice. Treatment of mice with Dex (10 µg intraperitoneally daily from day 2) afforded potent antiarthritic effects highly attenuated in the knockouts: macroscopic changes were mirrored by histopathological findings and pro-inflammatory gene (eg, Nos2) expression. Presence of proteinase 3 mRNA in the arthritic joints led the authors to test AnxA1 and the mutant SuperAnxA1 (1 µg intraperitoneally daily in both cases from day 2), with the latter one being able to accelerate the resolving phase of the disease. CONCLUSION: AnxA1 is an endogenous determinant for the therapeutic efficacy of Dex in inflammatory arthritis. Such an effect can be partially mimicked by application of SuperAnxA1 which may represent the starting point for novel antiarthritic therapeutic strategies.

Endogenous galectin-1 and acute inflammation: emerging notion of a galectin-9 pro-resolving effect.

The role of endogenous galectin-1 (Gal-1) in acute inflammation has been poorly investigated. We therefore performed the carrageenan-induced paw edema model in wild-type and Gal-1(-/-) mice. On subplantar injection of carrageenan, Gal-1(-/-) mice displayed a similar first phase of edema (≤24 hours) to wild-type mice; however, a much less pronounced second phase (48 to 96 hours) was evident in this genotype. This reduced inflammation was associated with lower paw expression of inflammatory genes and cell infiltrates. Analysis of galectin protein and mRNA expression revealed high expression of Gal-1 in wild-type paws during resolution (≥48 hours), with some expression of galectin-9 (Gal-9). Administration of stable Gal-1 to wild-type mice completely ablated the first phase of edema but was ineffective when administered therapeutically at the 24-hour time point. Conversely, Gal-9 administration did not alter the first phase of edema but significantly reduced the second phase when administered therapeutically. This suggests anti-inflammatory actions for both proteins in this model albeit at different phases of the inflammatory response. Collectively, these data indicate that the absence of endogenous Gal-1 results in an abrogated response during the second phase of the edema reaction.

Suppression of endothelial P-selectin expression contributes to reduced cell trafficking in females: an effect independent of NO and prostacyclin.

OBJECTIVE: Sex hormones underlie the lower incidence of cardiovascular disease in premenopausal women. Vascular inflammation is involved in the pathogenesis of several cardiovascular diseases and it has been reported that sex hormones modulate inflammatory responses but mechanisms responsible for these effects are not yet fully established. Herein, we assessed whether sex differences in leukocyte recruitment might exist and investigated the underlying mechanisms involved in this response. METHODS AND RESULTS: Treatment with interleukin-1ß (IL-1ß) or tumor necrosis factor-α caused leukocyte rolling, adhesion, and emigration in mesenteric postcapillary venules in vivo that was substantially reduced in female mice compared with male mice; this difference was abolished by ovariectomy and partially restored by estrogen replacement. Deletion of endothelial nitric oxide (NO) synthase or cyclooxygenase-1 alone or in combination did not alter the leukocyte recruitment in IL-1ß-treated females but significantly enhanced this response in male mice. Treatment of murine pulmonary endothelial cells with IL-1ß increased expression of P-selectin in male but not female cells. CONCLUSIONS: We have demonstrated a profound estrogen-dependent and NO and prostacyclin-independent suppression of leukocyte recruitment in females.

Auditory Brainstem Responses (ABR) changes in children treated with high doses cisplatin.

INTRODUCTION: Cisplatin can cause cochlear damage by oxidative stress in hair cells, but there are few studies regarding toxicity in the central auditory pathways. OBJECTIVE: To study cisplatin neurotoxicity in the central auditory pathways in children treated with high doses cisplatin for solid malignant tumors. METHODS: Thirteen children (Group S) aged 3-19 years who had been treated with cisplatin (60-120 mg/m(2)/cycle) were studied using evoked otoacoustic emissions (EOA), conventional auditory evaluation and auditory brainstem response (ABR). Thirteen normal children matched for age and sex composed the control group (Group C). RESULTS: Group S - 7.5% percent of ears showed enlargement of latencies of waves I and V, and 3.8% of wave III. Six ears (23%) showed enlarged interpeak intervals. Four ears showed increased interpeak I-III and two showed increased interpeak III-V. The results were compared using the Mann-Whitney test. Interpeak III-V differed significantly between groups S and C when only the left ears were considered. EOA results were normal in both groups. DISCUSSION/CONCLUSION: Abnormal values in the interpeak I-III associated with normal distortion product OEA suggest neurotoxicity in the brainstem pathways. The statistical significance reached only in the left ear may be due to small number of cases studied.

Alterations in innate immune responses of patients with chronic rhinosinusitis related to cystic fibrosis.

The role of phagocytes of children with cystic fibrosis (CF) associated with different phenotypes of chronic rhinosinusitis (CRS) is unclear. The aim of this study was to evaluate the phagocytic capacity of blood neutrophils and monocytes and production of superoxide anion by phagocytes in patients with CF with or without chronic rhinosinusitis and with or without nasal polyps (NP). This cross-sectional study was established in 2015-2017 in a tertiary reference center to the CF treatment, Brasilia, Brazil. Sample included 30 children volunteers with CRS related to CF (n = 16) and control subjects (n = 14). Epidemiological and clinical data were compared. Collection of 15 mL of peripheral blood and nasal endoscopy to identify the presence or absence of nasal polyps (NP) were performed. Phagocytosis of Saccharomyces cerevisiae by pathogen-associated molecular pattern receptors and opsonin receptors was assessed. Superoxide anion production was evaluated. The control group showed a higher phagocytic index to monocytes and neutrophils than to the CF or CF+CRS with NP groups [Kruskal-Wallis p = 0.0025] when phagocytosis were evaluated by pathogen-associated molecular pattern receptors (5 yeasts/cell). The phagocytic index of the CF+CRS without NP group was higher than in the CF+CRS with NP group (Kruskal-Wallis p = 0.0168). In the control group, the percentage of phagocytes involved in phagocytosis and superoxide anion production (74.0 ± 9.6%) were higher in all CF groups (p < 0,0001). The innate immune response, represented by phagocytic activity and superoxide anion production by monocytes and neutrophils was more impaired in patients with CF related or not related to CRS than in the control group. However, the phagocytic function of patients without NP showed less impairment.

Anti-inflammatory and antiosteoclastogenesis properties of endogenous melanocortin receptor type 3 in experimental arthritis.

The development of biological therapies has improved management of rheumatoid arthritis. However, costs and unresponsiveness to therapy in a sizeable proportion of patients limit their use, making it imperative to identify new targets for drug development programs. Here we investigated the melanocortin-receptor type 3 (MC(3)) pathway. Gene-deficient mice were subjected to a model of serum-transfer-induced arthritis and joints analyzed for gene expression (cytokines, MCs) and morphology. Pharmacological analyses were also conducted in this model. Osteoclastogenesis was studied from bone marrow cells. Mc(3)(-/-) mice displayed an exacerbated inflammatory arthritis, associated with prominent bone erosion and higher articular expression of Rankl. Osteoclastogenesis studied from Mc(3)(-/-) bone marrow cells revealed a higher degree of responsiveness to Rankl, linked to prolonged NF-κB activation compared to wild types. Up-regulation of a discrete set of inflammatory genes, including Il-1ß, Il-6, and Nos2, was measured in Mc(3)(-/-) mice, and a marked up-regulation of joint Mc(3) accompanied arthritis resolution in wild-type mice. Administration of an MC(3) agonist, D[Trp8]-γ-MSH, attenuated disease incidence and severity in wild-type but not Mc(3)(-/-) mice. Overall, these findings identify MC(3)-mediated signaling as a beneficial pathway in experimental arthritis; hence this receptor is a novel target for the development of therapeutics for arthritis.

Melanocortin control of cell trafficking in vascular inflammation.

Over 20 years of research based upon application of experimental models of inflammation and tissue injury have revealed exquisite controlling functions for melanocortin hormones and, subsequently, their synthetic derivatives. More recent discoveries have shed light on the receptor targets responsible for these effects, leading to what could be the next step-change for this line of research, the development of novel therapeutics for the control of human inflammatory pathologies. Here we review some of this work with particular emphasis on more recent studies that have substantiated the activities of melanocortin peptides to reveal important regulatory functions for their receptors in vascular inflammation and disease models. Moreover, we summarise the drug discovery activities (for what is published knowledge) attempting to capitalise on this wealth of research on melanocortins, though we should not forget the successful employment of ACTH to treat human gouty arthritis. Altogether, this chapter would corroborate and flare the enthusiasm for this line of research, as we are confident that the right times might have arrived to develop novel anti-arthritic and tissue-protective compounds that will be acting by mimicking the way our endogenous melanocortins would act to exert their homeostatic and check-point functions.

A novel peptide agonist of formyl-peptide receptor-like 1 (ALX) displays anti-inflammatory and cardioprotective effects.

Activation of the formyl-peptide receptor-like (FPRL) 1 pathway has recently gained high recognition for its significance in therapy of inflammatory diseases. Agonism at FPRL1 affords a beneficial effect in animal models of acute inflammatory conditions, as well as in chronic inflammatory diseases. TIPMFVPESTSKLQKFTSWFM-amide (CGEN-855A) is a novel 21-amino acid peptide agonist for FPRL1 and also activates FPRL2. CGEN-855A was discovered using a computational platform designed to predict novel G protein-coupled receptor peptide agonists cleaved from secreted proteins by convertase proteolysis. In vivo, CGEN-855A displays anti-inflammatory activity manifested as 50% inhibition of polymorphonuclear neutrophil (PMN) recruitment to inflamed air pouch and provides protection against ischemia-reperfusion-mediated injury to the myocardium in both murine and rat models (36 and 25% reduction in infarct size, respectively). Both these activities are accompanied by inhibition of PMN recruitment to the injured organ. The secretion of inflammatory cytokines, including interleukin (IL)-6, IL-1beta, and tumor necrosis factor-alpha, was not affected upon incubation of human peripheral blood mononuclear cells with CGEN-855A, whereas IL-8 secretion was elevated up to 2-fold upon treatment with the highest CGEN-855A dose only. Collectively, these new data support a potential role for CGEN-855A in the treatment of reperfusion-mediated injury and in other acute and chronic inflammatory conditions.

Inhibitory control of endothelial galectin-1 on in vitro and in vivo lymphocyte trafficking.

Galectin-1 (Gal-1) is a beta-galactoside-binding protein, the expression of which is increased in endothelial cells on exposure to proinflammatory stimuli. Through binding of several receptors (CD7, CD45, and CD43) Gal-1 is known to induce apoptosis of activated T lymphocytes, an effect thought to mediate the beneficial effects it exerts in various inflammatory models. The data presented here highlights another function for Gal-1, that of a negative regulator of T-cell recruitment to the endothelium under both physiological and pathophysiological conditions. We have shown, using siRNA to knockdown Gal-1 in endothelial cells, that endogenous Gal-1 limits T-cell capture, rolling, and adhesion to activated endothelial cells under flow. Furthermore, the reverse effect is observed when exogenous human recombinant Gal-1 is added to activated endothelial monolayers whereby a dramatic reduction in lymphocyte recruitment is seen. These findings are corroborated by studies in Gal-1 null mice in which homing of wild-type (WT) T lymphocytes is significantly increased to mesenteric lymph nodes and to the inflamed paw in a model of delayed-type hypersensitivity. In conclusion, mimicking endothelial Gal-1 actions would be a novel strategy for controlling aberrant T-cell trafficking, hence for the development of innovative anti-inflammatory therapeutics.

Inflamed phenotype of the mesenteric microcirculation of melanocortin type 3 receptor-null mice after ischemia-reperfusion.

The existence of anti-inflammatory circuits centered on melanocortin receptors (MCRs) has been supported by the inhibitory properties displayed by melanocortin peptides in models of inflammation and tissue injury. Here we addressed the pathophysiological effect that one MCR, MCR type 3 (MC3R), might have on vascular inflammation. After occlusion (35 min) and reopening of the superior mesenteric artery, MC3R-null mice displayed a higher degree of plasma extravasation (45 min postreperfusion) and cell adhesion and emigration (90 min postreperfusion). These cellular alterations were complemented by higher expression of mesenteric tissue CCL2 and CXCL1 (mRNA and protein) and myeloperoxydase, as compared with wild-type animals. MC1R and MC3R mRNA and protein were both expressed in the inflamed mesenteric tissue; however, no changes in vascular responses were observed in a mouse colony bearing an inactive MC1R. Pharmacological treatment of animals with a selective MC3R agonist ([D-Trp(8)]-gamma-melanocyte-stimulating hormone; 10 microg i.v.) produced marked attenuation of cell adhesion, emigration, and chemokine generation; such effects were absent in MC3R-null mice. These new data reveal the existence of a tonic inhibitory signal provided by MC3R in the mesenteric microcirculation of the mouse, acting to down-regulate cell trafficking and local mediator generation.

Immunomodulating and antiviral activities of Uncaria tomentosa on human monocytes infected with Dengue Virus-2.

Uncaria tomentosa (Willd.) DC., a large woody vine native to the Amazon and Central American rainforests has been used medicinally by indigenous peoples since ancient times and has scientifically proven immunomodulating, anti-inflammatory, cytotoxic and antioxidant activities. Several inflammatory mediators that are implicated in vascular permeability and shock are produced after Dengue Virus (DENV) infection by monocytes, the primary targets for virus replication. Here we assessed the immunoregulatory and antiviral activities from U. tomentosa-derived samples, which were tested in an in vitro DENV infection model. DENV-2 infected human monocytes were incubated with U. tomentosa hydro-alcoholic extract or either its pentacyclic oxindole alkaloid-enriched or non-alkaloid fractions. The antiviral activity was determined by viral antigen (DENV-Ag) detection in monocytes by flow cytometry. Our results demonstrated an in vitro inhibitory activity by both extract and alkaloidal fraction, reducing DENV-Ag+ cell rates in treated monocytes. A multiple microbead immunoassay was applied for cytokine determination (TNF-alpha, IFN-alpha, IL-6 and IL-10) in infected monocyte culture supernatants. The alkaloidal fraction induced a strong immunomodulation: TNF-alpha and IFN-alpha levels were significantly decreased and there was a tendency towards IL-10 modulation. We conclude that the alkaloidal fraction was the most effective in reducing monocyte infection rates and cytokine levels. The antiviral and immunomodulating in vitro effects from U. tomentosa pentacyclic oxindole alkaloids displayed novel properties regarding therapeutic procedures in Dengue Fever and might be further investigated as a promising candidate for clinical application.

Transient and distortion product evoked oto-acoustic emissions in normal hearing patients with and without tinnitus.

OBJECTIVE: To test the hypothesis that tinnitus begins with outer hair cell dysfunction by recording transient (TEOAE) and distortion product evoked (DPOAE) oto-acoustic emissions in patients with normal hearing with (study group, SG) and without tinnitus (control group, CG). STUDY DESIGN: Case control study. SUBJECTS AND METHODS: SG had 32 patients with pure tone thresholds below 25 dB in the 500 to 8000 Hz interval. CG had 37 age- and gender-matched patients with similar thresholds. All patients had normal tympanograms and stapedial reflexes. TEOAE were recorded with wide band click in continuous mode at 80-dB peak SPL. DPOAE were recorded with f1/f2 = 1.22 and intensities of 65 dB (f1) and 55 dB (f2) SPL. RESULTS: DPOAE were abnormal in 68.4% of SG and in 50% of CG (P = 0.036). TEOAE were abnormal in 70.2% of SG and in 16.10% of CG (P = 0.0001). CONCLUSION: SG had significantly higher prevalence of abnormal TEOAE and DPOAE than CG.

Imaging case study of the month: traumatic pneumolabyrinth.

Pneumolabyrinth is a condition in which air is present in the vestibule and/or in the cochlea. Air inside the inner ear structures is uncommon, and is not detected even in otic capsule-violating fractures or in transverse fractures of the temporal bone. It is rarely described in the literature. We present a longitudinal computed tomography (CT) study of a significant pneumolabyrinth due to temporal bone trauma in a 31-year-old man. Routine CT of the cranium performed 3 hours after the accident showed air inside the vestibule (pneumolabyrinth). Two days later, a new CT study was performed. The air in the vestibule was partially resorbed. There was opacity over the oval window niche and the promontory. Thirteen months after the initial head trauma, another CT examination showed a fracture line running from the vestibule to the posterior wall of the petrous bone. The patient had profound sensorineural hearing loss after the trauma, and the pneumolabyrinth cleared over a few months. Surgical treatment was not indicated.

Viral etiology for inner ear diseases: proven, unproven, unlikely.

This is a revision article that deals with the broad field of inner ear disease caused by viral infections. Some of these entities have been proven to have a viral etiology. Others have strong evidence in favor of a viral causation but still cannot be considered as a viral disease. Finally, other entities are suggestive of a viral etiology but when the whole body of evidence is considered one concludes that a viral etiology is indeed unlikely. We review the literature and add our own experience in this subject. Clearly, the most important evidence about this subject came from the study of temporal bone histopathology. Certainly, we can learn much more if we continue to collect and study temporal bone specimens histopathologically.

Aromatic lipoxin A4 and lipoxin B4 analogues display potent biological activities.

Lipoxins are a group of biologically active eicosanoids typically formed by transcellular lipoxygenase activity. Lipoxin A4 (LXA4) and Lipoxin B4 (LXB4) biosynthesis has been detected in a variety of inflammatory conditions. The native lipoxins LXA4 and LXB4 demonstrate potent antiinflammatory and proresolution bioactions. However, their therapeutic potential is compromised by rapid metabolic inactivation by PG dehydrogenase-mediated oxidation and reduction. Here we report on the stereoselective synthesis of aromatic LXA4 and LXB4 analogues by employing Sharpless epoxidation, Pd-mediated Heck coupling, and diastereoselective reduction as the key transformations. Subsequent biological testing has shown that these analogues display potent biological activities. Phagocytic clearance of apoptotic leukocytes plays a critical role in the resolution of inflammation. Both LXA4 analogues (1R)-3a and (1S)-3a were found to stimulate a significant increase in phagocytosis of apoptotic polymorphonuclear leukocytes (PMN) by macrophages, with comparable efficacy to the effect of native LXA4, albeit greater potency, while the LXB4 analogue also stimulated phagocytosis with a maximum effect observed at 10-11 M. LX-stimulated phagocytosis was associated with rearrangement of the actin cytoskeleton consistent with that reported for native lipoxins. Using zymosan-induced peritonitis as a murine model of acute inflammation (1R)-3a significantly reduced PMN accumulation.

Evaluation of early postoperative morbidity in pediatric tonsillectomy with the use of sucralfate.

OBJECTIVE: The objective of this study is to evaluate the efficacy of sucralfate in alleviating posttonsilectomy morbidity in a pediatric group of patients. METHODS: A prospective, double-blind, randomized, and placebo-controlled study comparing the irrigation of a solution containing either 1g of sucralfate (study group) or 1g of lactulose (control group) was performed on 69 children aged 3-12 years, who underwent tonsillectomy at the University Hospital of Brasilia Medical School. The children were randomly assigned and each one used a solution containing sucralfate or lactulose to swish and swallow four times daily during 7 days. Eleven patients were excluded. The anesthetic was standardized and no premedication was used. Pain magnitude using an "Oucher" scale, nausea, vomiting, bleeding, earache, analgesic drug intake, changes in the interincisor teeth distance, and changes in the weight and temperature were assessed by the surgeon 6, 24h, and 7 days after the surgery. RESULTS: Patients in the study group had significantly lower pain scores in the initial 6 postoperative hours (p<0.05). The difference between the two groups was not statistically significant for the other periods following the procedure or on the evaluation of the other indices. CONCLUSIONS: The use of the sucralfate in pediatric patients undergoing tonsillectomy was not effective in reducing the postoperative morbidity according to the parameters used in this study. The surgical technique with careful mucosal dissection associated with postoperative caries could be more important in the reduction of posttonsilectomy morbidity.

Effects of endothelin ETA receptor antagonism on granulocyte and lymphocyte accumulation in LPS-induced inflammation.

Endothelin peptides play active roles in different aspects of inflammation. This study investigates the contribution of endogenous endothelins to lipopolysaccharide (LPS) pulmonary inflammation by assessing the influence of ET(A) receptor antagonism on leukocyte accumulation, granulocyte adhesion molecule expression, and chemokine/cytokine modulation. Local pretreatment with BQ-123 or A-127722 (150 pmol), two selective and chemically unrelated endothelin ET(A) receptor antagonists, inhibits neutrophil and eosinophil accumulation in LPS-induced pleurisy at 24 h but not neutrophil migration at 4 h. The effect of endothelin antagonism on neutrophil accumulation at 24 h was concomitant with inhibition of eosinophil and CD4 and CD8 T lymphocyte influx. It is surprising that the ET(A) receptor blockade did not inhibit the accumulation of gammadelta T lymphocytes, cells that are important for granulocyte recruitment in this model. Blockade of ET(A) receptors did not influence the expression of adhesion molecules (CD11b, CD49d) on granulocytes but abrogated the increase in tumor necrosis factor alpha levels 4 h after LPS stimulation and also markedly inhibited increases in levels of interleukin-6 and keratinocyte-derived chemokine/CXC chemokine ligand 1 but not eotaxin/chemokine ligand 11. Thus, acting via ET(A) receptors, endogenous endothelins play an important role in early cytokine/chemokine production and on granulocyte and lymphocyte mobilization in LPS-induced pleurisy.

Quantitative study of the vestibular sensory epithelium in cochleosaccular dysplasia.

BACKGROUND: Cochleosaccular dysplasia is the most common pathologic finding seen in children with profound congenital sensorineural hearing loss. There has been no quantitative study on the peripheral vestibular system in cochleosaccular dysplasia. OBJECTIVE: To investigate quantitatively the extent of pathologic changes of the vestibular sensory epithelium in cochleosaccular dysplasia. SUBJECTS AND METHODS: Thirteen temporal bones with congenital deafness from 10 individuals were selected for this study from the temporal bone collection of University of Minnesota that showed suitable pathologic findings for the histopathologic criteria of cochleosaccular dysplasia. Age-matched normal control temporal bones were also selected. The vestibular hair cells including types I and II hair cells were counted separately in the saccular macula, utricular macula, and three cristae of the semicircular canals using Nomarski microscopy. RESULTS: The hair cell densities of types I and II hair cells in the macula of the saccule in cochleosaccular dysplasia were significantly decreased compared with the data of normal subjects. Both types I and II hair cells in the utricular macula and the cristae of the three semicircular canals in cochleosaccular dysplasia were well preserved, and no significant difference was observed between findings of cochleosaccular dysplasia and normal controls in the utricle and the three semicircular canals. CONCLUSIONS: In cases with cochleosaccular dysplasia, the neurosensorial hair cells of the saccule were affected; however, the osseous labyrinth, the membranous utricle, and the semicircular canals were normal. Further studies should be performed to establish the pathogenesis of cochleosaccular dysplasia in humans.

Massive endolymphatic sac and vestibular aqueduct in Mondini dysplasia.

A postmortem study was performed on the bilateral temporal bones of a 90-year-old woman who had a lifelong profound hearing impairment. The histopathologic findings included severe Mondini dysplasia with unusual enlargement of the vestibular aqueducts and endolymphatic sacs. Dehiscent carotid arteries and dehiscent facial nerves were also present. The clinical and surgical aspects of the case are discussed based on the histopathologic findings. The physician should be prepared to diagnose congenital hearing impairment promptly to avoid complications during the clinical and surgical treatment of patients with Mondini dysplasia.