Efficacy of endoscopic static pressure/area assessment of the passive pharynx in predicting uvulopalatopharyngoplasty outcomes

OBJECTIVES/HYPOTHESIS

Although uvulopalatopharyngoplasty (UPPP) is an attractive surgical treatment for obstructive sleep apnea (OSA), the unpredictable outcome limits application of the procedure. Since UPPP corrects only retropalatal airway (RP) patency, we hypothesized that response to UPPP is determined by collapsibility of the retroglossal airway (RG), where UPPP does not correct.

METHODS

We estimated closing pressure (Pclose) for each pharyngeal segment by endoscopically obtaining the static pressure/area relationship of the passive pharynx in completely paralyzed and anesthetized patients with sleep-disordered breathing (n = 41) before UPPP. Preferable response to UPPP was defined as the number of oxygen dips (ODI), obtained by nocturnal oximetry, less than 10 h(-1) after UPPP.

RESULTS

Patients with negative Pclose at RG responded to UPPP significantly better than those with positive Pclose at RG (22/30 [73%] vs. 3/11 [27%], P<.05). ODI after UPPP was significantly correlated with age, Pclose at RP, and Pclose at RG.

CONCLUSIONS

Endoscopic assessment of anatomic abnormality of the pharynx in paralyzed patients with sleep-disordered breathing under general anesthesia has clinical value for the improvement of UPPP outcome.

Comparative role of peptide leukotrienes and histamine in the development of nasal mucosal swelling in nasal allergy

To evaluate the importance of histamine and peptide leukotrienes (LTs) in the development of nasal mucosal swelling in nasal allergy, H1 receptor antagonist (mequitazine, 6 mg, in 2 divided doses, Rhône-Poulenc Rorer, France) and LT receptor antagonist (ONO-1078, pranlukast, 450 mg, in 2 divided doses, Ono Pharmaceutical Co, Ltd, Osaka) were administered orally for 7 days to 16 subjects with perennial nasal allergy to house dust mites, and the effects of receptor blockers of these chemical mediators on the effective cross-sectional area of the nasal cavity (ECA) at rest, at exercise load, at antigen challenge, and at exercise load following antigen challenge were studied. After the administration of H1 receptor antagonist, ECAs at all measurement points slightly increased, but no statistical significance was observed. On the other hand, LT receptor antagonist inhibited ECAs 10 minutes after exercise load, just after the end of antigen challenge, 10 minutes later, and at exercise load following antigen challenge with statistical significance. These results suggest that LTs are involved markedly, and histamine slightly, in the development of nasal mucosal swelling in nasal allergy.

Effect of ion transport inhibitors and methacholine on short-circuit current of isolated guinea pig nasal epithelium

To clarify the ion/water secretion mechanism in the nasal epithelial cells, the Ussing chamber method was applied to the nasal mucosa isolated from guinea pigs. The preparation, which contained surface epithelial cells, showed a small but consistent potential difference between mucosal and submucosal sides (mucosal surface negative to submucosa). The short-circuit current (Isc) across the epithelial layer was measured, and the effects of Na+ and/or Cl- transport inhibitors and methacholine (MCh) on Isc were analyzed. The basal Isc was almost totally suppressed by the combined application of amiloride (Na+ transport inhibitor) and low-Cl- Krebs Ringer (KR) solution or solutions containing Cl- transport inhibitors (furosemide or DPC). The application of MCh elicited triphasic Isc responses, i.e., initial transient increase (phase 1) followed by a small decrease (phase 2) and further sustained increase (phase 3) in Isc. A possible ionic mechanism underlying phase 1 and 3 responses was analyzed. The Phase 1 response was greatly reduced by low-Cl- KR solution or furosemide but not influenced by amiloride. The Phase 3 response was augmented by amiloride and suppressed by low-Cl- KR solution, furosemide or DPC. These findings indicated that the basal Isc was associated with Cl- secretion and/or Na+ absorption across epithelial cells under short-circuit condition and that MCh increased Isc probably via enhancing Cl- secretion in the nasal surface epithelial cell.

Diesel exhaust particulates upregulate histamine receptor mRNA and increase histamine-induced IL-8 and GM-CSF production in nasal epithelial cells and endothelial cells

BACKGROUND

Histamine is the most important chemical mediator in the pathogenesis of nasal allergy. Diesel exhaust particulates (DEPs) are common air pollutants from diesel engine-powered car exhaust and cause chronic airway diseases. Recently we observed that the nasal reactivity to histamine was enhanced in diesel exhaust-exposed guinea-pigs. It was also revealed that epithelial cells and endothelial cells in the airway produce certain cytokines in response to histamine.

OBJECTIVE

We examined the effects of DEP extract on the expression of histamine H1 receptor (H1R) mRNA in human nasal epithelial cells (HNECs) and human mucosal microvascular endothelial cells (HMMECs), and on the production of IL-8 and GM-CSF induced by histamine.

METHODS

HNECs and HMMECs were isolated from human nasal mucosa specimens. HNEC and HMMEC monolayers were cultured in the presence or absence of DEP extract. The change in the expression of H1R mRNA was then evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) and the Southern blot analysis. To investigate the effects of DEP extract on the histamine-induced cytokine production, HNEC and HMMEC monolayers were cultured in the presence or absence of DEP extract for 3-24 h. After three washes with PBS, they were then incubated with 10(-6) mol/L histamine for 24 h. The amounts of IL-8 and GM-CSF in the culture media were measured by enzyme-linked immunoabsorbent assay.

RESULTS

DEP extract increased the expression of H1R mRNA in both HNECs and HMMECs. The amount of IL-8 and GM-CSF, induced by histamine, was significantly higher in DEP extract pretreated HNECs and HMMECs than nontreated HNECs and HMMECs.

CONCLUSION

These results strongly suggest that DEP accelerates the inflammatory change by not only directly upregulating H1R expression but also increasing histamine-induced IL-8 and GM-CSF production.

[Late phase II clinical study of RP56976 (docetaxel) in patients with advanced/recurrent head and neck cancer]

A late phase II clinical study of RP56976 (docetaxel), a new anticancer agent for advanced/recurrent head and neck cancer, was conducted in 29 institutions all over Japan as a multi-institutional cooperative study. Docetaxel was administered by 1 to 2-hour intravenous infusion at a dose of 60 mg/m2 every 3 to 4 weeks. Of 63 patients eligible in this study, 59 were judged as complete cases. Complete response (CR) was observed in 1 patient, partial response (PR) in 13, no change (NC) in 25, and progressive disease (PD) in 20, for an overall response rate of 22.2% (14/63, 95% CI: 12.7-34.5%) in eligible cases, and 23.7% (14/59, 95% CI: 13.6-36.6%) in complete cases. Previously treated patients showed a 17.9% (10/56) response rate, whereas treatment--naive patients showed a 57.1% (4/7) response rate. Among 46 patients who received prior chemotherapy, one CR and 7 PR were observed with a 17.4% response rate. Major hematological toxicities were leucopenia in 95.1% (> or = grade 3, 59.7%) and neutropenia in 90.3% (> or = grade 3, 79.0%). Other severe toxicities (> or = grade 3) included anorexia in 9.7% (6 cases), diarrhea in 3.2% (2 cases), dyspnea in 3.2% (2 cases), and fatigue in 3.2% (2 cases). One patient had a grade 3 interstitial pneumonia; however, symptoms were resolved by the administration of corticosteroids. During this study, one patient died due to multiple organ failure (MOF) caused by disseminated intravascular coagulation (DIC), and this case was reported as a therapy-related death. Based on these results, docetaxel is an active agent for treatment of head and neck cancer.

Analysis of factors affecting long-term treatment results of adenoid cystic carcinoma of the nose and paranasal sinuses

At Akita University Hospital (from 1971 to 1987) and at Chiba University Hospital (from 1983 to 1988), 17 patients with adenoid cystic carcinoma of the nose and paranasal sinuses were treated by en bloc tumor resection followed by primary reconstruction of the maxilla. Pre- and postoperative radiation was combined in 5 and 6 patients, respectively. Ten-year cancer-free survival rates were 59.3% in the 12 patients with maxillary sinus tumors and 50% in the 4 patients with nasal tumors. One patient with a sphenoid sinus tumor died within 5 years. Ten-year cancer-free survival was affected markedly by grade of tumor extension. Among T1N0M0 and T2N0M0 patients (of which there were 1 and 7, respectively), only 1 died of unrelated causes, and 6 patients survived cancer-free for more than 10 years. However, 4 of the 6 T3N0M0 patients died, and the cause of death was distant metastasis in 2, intracranial tumor extension in 1, and unrelated causes in 1. All 3 T4N0M0 patients died, 2 due to intracranial tumor extension and 1 of unrelated causes. The cause of death was distant metastasis in 3, local recurrence in 3, 2 of whom had intracranial tumor extension, and unrelated causes in 2. Prevention of distant metastasis and intracranial tumor extension was considered to be crucial for improving treatment results after en bloc tumor resection. Preoperative radiation was thought to decrease incidence of distant metastasis. In 5 patients who had preoperative radiation. 4 survived cancer-free for more than 10 years, and only 1 patient died of unrelated cause. However. of the 6 patients who had postoperative radiation, 2 died of distant metastasis and another 2 died of intracranial tumor extension. Of the 6 patients who did not have radiation therapy, the causes of death were local recurrence in 1, distant metastasis in 1 and unrelated causes in 1. Preoperative radiation in 5 patients showed histopathologically moderate or marked degeneration and necrosis of tumors in all patients. Although the number of patients in this study is too small to allow statistical analysis of the data, our present modality of treatment for adenoid cystic carcinoma of the nose and paranasal sinuses is routine combination of preoperative full dose radiation, en bloc tumor resection and primary reconstruction, including en bloc resection of the cranial base in selected T4 patients.

Metastasis of renal cell cancer to the ethmoid sinus

The origin of metastatic tumors in the nasal or paranasal sinuses is often renal cancer, and metastasis to the nasal or paranasal sinuses sometimes takes a long time after nephrectomy. The present paper deals with one patient with metastasis of renal cancer to the ethmoid sinus 2 years after nephrectomy. Even though many metastatic tumors originating from renal cancer develop in multiples, most metastatic tumors in the nasal or paranasal sinuses are single and treated surgically. However, even if multiple tumors are found in the nasal and paranasal region and other organs, surgery will be effective in preventing epistaxis and subsequent anemia. Also, when removing a tumor it will be effective to identify the feeding arteries of the tumor, perform embolization therapy, and clip the necessary arteries.

An electrophysiological study of pterygopalatine ganglion neurons in the rabbit

A preparation was developed to investigate the synaptic connections of the pterygopalatine ganglion (P.P.G.) neurons of the rabbit. Many neurons received synaptic inputs from more than one preganglionic fiber in the vidian nerve (preganglionic nerve) with a wide range of conduction velocities. It is assumed that P.P.G. neurons integrate synaptic inputs from the higher centers. In some neurons. nicotinic fast excitatory postsynaptic potentials (e.p.s.p.s) were evoked in response to stimulation of one posterior nasal nerve, and also an antidromic action potential occurred in response to stimulation of the other posterior nasal nerve. Fast e.p.s.p.s were recorded from a ganglion neuron in response to the cooling stimulation of the nasal mucosa. These results revealed that the ganglionic reflex are mediated through the nasal afferent fibers exists in the P.P.G. Moreover, the appearance of slow inhibitory postsynaptic potentials (slow i.p.s.p.s) and slow excitatory postsynaptic potentials (slow e.p.s.p.s) in response to repetitive stimuli of the vidian nerve may influence the synaptic transmissions of P.P.G. neurons. The P.P.G. plays a significant role as a complicated key point of signal transmissions from both the periphery and higher centers.

Analysis of long-term results of our combination therapy for squamous cell cancer of the maxillary sinus

Seventy-four patients between 1971 and 1982 in Period I and 32 patients between 1982 and 1987 in Period II with maxillary sinus squamous cell cancer were treated by combination therapy consisting of preoperative LINAC X-ray irradiation with 5-flourouracil intra-arterial chemotherapy followed by maxillectomy and primary reconstruction. In Period II, 21 patients received preoperative cisplatinum (CPPP) microcapsule chemoembolization and pepleomycin (PEP) i.m. and or postoperative CDDP i.v. with PEP i.m. in addition to the combination therapy administered in Period I depending on systemic conditions, tumor stage and histopathological type. Five and 10-year crude survival rates were 68.9% and 55.4%, respectively, for Period I and 71.9% and 56.3% for Period II, with no significant difference between the two trials. In 21 selected patients in Period II, who had additional chemotherapy with preoperative CDDP chemoembolization and/or postoperative i.v. infusion of CDDP with pepleomycin i.m., 5 and 10-year survival rates were 85.7% and 61.9%, respectively.

The effect of ramatroban (BAY u 3405), a thromboxane A2 receptor antagonist, on nasal cavity volume and minimum cross-sectional area and nasal mucosal hemodynamics after nasal mucosal allergen challenge in patients with perennial allergic rhinitis

The thromboxane A2 receptor antagonist, ramatroban (BAY u 3405), was orally administered for 4 weeks at a daily dose of 150 mg (b.i.d.) to 10 patients with perennial allergic rhinitis who had a positive reaction to house dust challenge on nasal mucosa. Nasal cavity volume and minimum cross-sectional area were measured, and changes in nasal mucosal swelling were determined following allergen challenge with house dust. The influence on nasal mucosal hemodynamics was also investigated. Nasal cavity volume and minimum cross-sectional area were measured by acoustic rhinometry, and blood flow in the nasal mucosa was measured by laser Doppler flowmetry. Percent changes in values from baseline nasal cavity volume were significantly decreased by allergen challenge before ramatroban administration, but no significant decrease was noted after ramatroban administration. Similarly, percent changes in values from baseline nasal cavity minimum cross-sectional area were significantly decreased by allergen challenge before administration of ramatroban, but not after administration. Percent changes in values from baseline nasal mucosal hemodynamics were significantly increased by allergen challenge both before and after ramatroban administration, which thus had no effect on mucosal hemodynamics. These findings suggest that ramatroban might inhibit the increase in nasal mucosal swelling but has no effect on nasal mucosal hemodynamics.

Changes in nasal responsiveness to histamine and to specific antigen after laser surgery

An initial treatment with several kinds of anti-allergic medicines is useful for reducing nasal allergy symptoms in patients suffering from Japanese cedar pollinosis during the pollen season. Since laser surgery before the pollen season seems to have a preventive effect as well, it would be of interest to know the time course of changes in the nasal reactivity to specific and non-specific stimuli after laser surgery. In this study, we investigated the changes in the nasal reactivities to specific antigen and histamine after CO2 laser surgery. The nasal reactivities to both specific antigen and histamine were enhanced 2 weeks after the laser surgery. On the other hand, they were significantly reduced after 4 weeks. Our data strongly suggest. therefore. that laser surgery must be done more than 4 weeks before the start of the pollen season to avoid temporary enhancement of nasal allergy symptoms.

Effect of female hormones on the production of IL-4 and IL-13 from peripheral blood mononuclear cells

In this study we compared the concentrations of IL-4, IL-13, and IFN-gamma, which were produced by human peripheral blood mononuclear cells (PBMC) in the presence or absence of preincubation with beta-estradiol or progesterone both after a specific antigen challenge and without a specific antigen challenge. The concentrations of IL-4 and IL-13 from PBMC which had been preincubated with progesterone or gamma-estradiol for 18-24 h were significantly greater than those of IL-4 and IL-13 from PBMC which had been preincubated with PBS, the control. On the other hand, the concentration of IFN-gamma from PBMC was unchanged. We were able to confirm that the female hormones beta-estradiol and progesterone, at levels similar to those occurring during pregnancy, have the ability to induce production of IL-4 and IL-13 in human mononuclear cells. These results suggest that female hormones may aggravate nasal allergy symptoms during pregnancy by increasing IgE synthesis and inducing selective eosinophil infiltration.

Immunohistochemical diagnosis of a Merkel cell tumor in a dog

We examined the clinical and immunohistochemical features of a Merkel (neuroendocrine) cell tumor on the skin between the eyes of a 12-year-old male Yorkshire Terrier dog. The tumor was characterized by locally expansive dermal nodules composed of solid nests or clusters of epithelioid cells surrounded by fine fibrous stroma. Basal cell epithelioma, Merkel cell tumor, and extramedullary plasmacytoma were also considered as diagnoses. Because the cytoplasm of the tumor cells stained positively for cytokeratin and chromogranin A but not for immunoglobulins, the tumor was diagnosed as a Merkel cell tumor. An electron-microscopic study of a tissue specimen revealed electron-dense granules approximately 200 nm in diameter. These granules were irregularly dispersed throughout the cytoplasm of the tumor cells, which would be expected in neuroendocrine cells. Twelve months after resection, a 0.8-cm-diameter tumor recurred at the original site. However, further follow-up of 22 months revealed no evidence of additional tumor growth, invasion, or metastasis, so we concluded that this tumor was benign.

Salivary gland malignant myoepithelioma: a clinicopathologic and immunohistochemical study of ten cases

BACKGROUND

Malignant myoepithelioma (MME) of the salivary gland, also known as myoepithelial carcinoma, is rare and its biologic behavior has not been clarified fully.

METHODS

Ten cases of MME were analyzed for their clinicopathologic features and immunohistochemical characteristics, focusing on prognostic factors and tumor differentiation. In addition, six cases of benign myoepithelioma (BME) also were examined for comparison.

RESULTS

The ten patients with MME (3 men and 7 women) ranged in age from 48-81 years (mean, 61.9 years). Seven cases of MME arose in the parotid salivary gland, two in the submandibular salivary gland, and one in minor salivary glands of the soft palate. In the current series, the incidence of MME was 0.45% among 1945 cases of major salivary gland tumors. Seven cases of MME developed from a benign preexisting tumor (six in pleomorphic adenoma and one in BME). Four of nine patients with MME died of the disease and two patients developed a recurrence. It was shown that MMEs were comprised of one cell type or a combination of two cell populations; these included, in order of incidence, epithelioid, spindle, and plasmacytoid cells. Patients with MME with marked cellular pleomorphism and perineural invasion had a poor prognosis. Immunohistochemically, putative myoepithelial markers such as muscle actins, cytokeratin 14, vimentin, and calponin, and S-100 protein were expressed highly in MME. High and low molecular weight cytokeratins and epithelial membrane antigen also frequently were positive in MME. p53 expression was observed in five MME cases, four of which either recurred or were fatal. Cellular proliferative activity assessed by mitotic count and the Ki-67 labeling index was significantly higher in MME cases than in BME cases. In limited cases, such cellular proliferative activity was shown to have prognostic value. Ultrastructurally, the tumor cells displayed certain myoepithelial characteristics.

CONCLUSIONS

MME is a rare salivary gland tumor showing clinicopathologic diversity and presenting with various stages of myoepithelial differentiation. Histologic aggressiveness, marked cellular pleomorphism, p53 expression, and high cell proliferative activity were found to be correlated with a poor clinical outcome.

Salivary gland malignant myoepithelioma: a clinicopathologic and immunohistochemical study of ten cases

BACKGROUND

Malignant myoepithelioma (MME) of the salivary gland, also known as myoepithelial carcinoma, is rare and its biologic behavior has not been clarified fully.

METHODS

Ten cases of MME were analyzed for their clinicopathologic features and immunohistochemical characteristics, focusing on prognostic factors and tumor differentiation. In addition, six cases of benign myoepithelioma (BME) also were examined for comparison.

RESULTS

The ten patients with MME (3 men and 7 women) ranged in age from 48-81 years (mean, 61.9 years). Seven cases of MME arose in the parotid salivary gland, two in the submandibular salivary gland, and one in minor salivary glands of the soft palate. In the current series, the incidence of MME was 0.45% among 1945 cases of major salivary gland tumors. Seven cases of MME developed from a benign preexisting tumor (six in pleomorphic adenoma and one in BME). Four of nine patients with MME died of the disease and two patients developed a recurrence. It was shown that MMEs were comprised of one cell type or a combination of two cell populations; these included, in order of incidence, epithelioid, spindle, and plasmacytoid cells. Patients with MME with marked cellular pleomorphism and perineural invasion had a poor prognosis. Immunohistochemically, putative myoepithelial markers such as muscle actins, cytokeratin 14, vimentin, and calponin, and S-100 protein were expressed highly in MME. High and low molecular weight cytokeratins and epithelial membrane antigen also frequently were positive in MME. p53 expression was observed in five MME cases, four of which either recurred or were fatal. Cellular proliferative activity assessed by mitotic count and the Ki-67 labeling index was significantly higher in MME cases than in BME cases. In limited cases, such cellular proliferative activity was shown to have prognostic value. Ultrastructurally, the tumor cells displayed certain myoepithelial characteristics.

CONCLUSIONS

MME is a rare salivary gland tumor showing clinicopathologic diversity and presenting with various stages of myoepithelial differentiation. Histologic aggressiveness, marked cellular pleomorphism, p53 expression, and high cell proliferative activity were found to be correlated with a poor clinical outcome.

Upper airway motor outputs during sneezing and coughing in decerebrate cats

The purposes of the present study were to determine which upper airway movements cause a difference in the expiratory airflow pathway between sneezing and coughing, and to develop a new animal model for studying the neural mechanism of sneezing in paralyzed animals, i.e. fictive sneezing. We compared the upper airway motor patterns of sneezing and coughing, induced by electrical stimulation of the anterior ethmoidal nerve (AEN) and superior laryngeal nerve, respectively, in non-paralyzed decerebrate cats. Respiratory and laryngeal motor patterns that consisted of an inspiration phase, compression phase, and expulsion phase were observed for both sneezing and coughing. The main difference was observed in the activity of the elevator of the back of the tongue, styloglossus (SG) muscle, which was explosively activated during the expulsion phase of sneezing, whereas it was virtually silent during coughing. The nasopharyngeal closers were weakly to moderately activated during sneezing. Their activities during coughing were weaker than during sneezing. Furthermore, the AEN-induced activities of the phrenic and abdominal nerves and the lateral branch of the hypoglossal nerve (lat-XII), which innervates the SG muscle, in paralyzed cats were consistent with the activities of the diaphragm, abdominal, and SG muscles during actual sneezing in non-paralyzed cats. Thus, we conclude that tongue movement is the main difference in the motor outputs between sneezing and coughing, which probably causes greater nasal airflow in sneezing, and that it is necessary to record the activity of the lat-XII to identify fictive sneezing in paralyzed cats.

Yolk sac tumor with a unique uniform hepatoid pattern histology

BACKGROUND

Yolk sac tumors (YST) exhibit several different histological subtypes and the mechanisms of cellular differentiation and prognosis of each subtype remain unknown.

RESULTS

We report two infants with sacrococcygeal YST; one represented a typical histological subtype and the other showed a hepatoid subtype with uniform histology. The isoform of alpha-fetoprotein (AFP) in the patient with the hepatoid pattern was examined by lectin-affinity immunoelectrophoresis and represented as a YST, but not hepatocellular, subtype. The patient with typical YST responded well to VAB-6 combination chemotherapy. However, this regimen was only partially effective to the patient with the pure hepatoid histological subtype, and an etoposide with ifosfamide and cisplatin (VIP) regimen as a salvage chemotherapy combined with complete tumor resection was useful to achieve complete remission (CR). Both of the patients have been in CR for more than four years.

Effect of sex hormones on eosinophilic inflammation in nasal mucosa

We examined the effects of sex hormones on the functions of eosinophils. Treatment of eosinophils with beta-estradiol significantly enhanced the eosinophil adhesion to human mucosal microvascular endothelial cells (HMMEC), and eosinophils stimulated by a combination of beta-estradiol and progesterone showed significant induced degranulation. On the other hand, testosterone significantly reduced the eosinophil adhesion to HMMEC and eosinophil viability. The experiments from the series of studies might provide a partial explanation for the aggravation of asthma and some forms of rhinitis that occurs during pregnancy.

Developmental changes and functional properties of human memory T cell subpopulations defined by CD60 expression

The present study was undertaken to examine developmental changes of T cells expressing CD60 and their functional properties. Three-color immunofluorescence analysis revealed that the CD60 antigen was preferentially expressed on a proportion of memory (CD45RO+) CD4+ T cells, but less on memory CD8+ T cells, while this antigen is undetectable in naive (CD45RO-) T cells. A frequency of memory CD4+ T cells expressing CD60 in the peripheral blood was negligible in newborns and gradually increased with advancing age. CD60+ memory CD4+ T cells showed stronger proliferative responses to PPD and produced higher levels of IL-4 and IL-10 than CD60- ones, whereas production of IL-2 and IFN-gamma was similarly found in both cell subpopulations. In addition, it was shown that efficient helper activity for Ig production by B cells was predominated in CD60+ memory CD4+ T cells. These results suggest that CD60 may be primarily expressed on the functionally differentiated memory effector cells among circulating CD45RO+ CD4+ T cells.

Immunohistochemical study of E-cadherin and ZO-1 in allergic nasal epithelium of the guinea pig

Nasal epithelial damage during allergic inflammation was studied by observing the distribution of cell adhesion molecule E-cadherin and tight junction (zonula occludens) cell-cell contact associated protein ZO-1. The guinea pig model of nasal allergy, sensitized with intraperitoneally administered ovalbumin (OA) and subsequently challenged with OA intranasally, was used. In control epithelium, E-cadherin immunoreactivity was detected continuously along neighboring epithelial cell borders. ZO-1 spot-like immunoreactivity was detected in the apicolateral portion of epithelial cells corresponding to the tight junction (TJ) position, but no changes in immunoreactivity were found between control and challenged epithelia. In the challenged epithelium of sensitized animals, marked infiltration of eosinophils and structural changes, such as widening of the intercellular spaces and detachment of adjacent epithelial cells, were observed concurrently. In addition, spots negative for E-cadherin immunoreactivity were noted in the epithelium, associated with the extracellular deposition of eosinophil granule proteins. Immunoelectron microscopy revealed a decrease or disappearance of E-cadherin immunoreactivity, which took place not only in regions where intercellular spaces were wide and adjacent epithelial cells were detached, but also at the point of contact between infiltrating eosinophils and epithelial cells. Approximately 87% of eosinophils observed in the challenged epithelium were associated with such loss of E-cadherin immunoreactivity. These results suggest that the intimate epithelial cell contact mediated by E-cadherin is loosened as a consequence of eosinophil infiltration, which may trigger the initial step of subsequent epithelial destruction in allergic states.

The potential role of interleukin-13 in eosinophilic inflammation in nasal mucosa

BACKGROUND

Recent studies have revealed that interleukin (IL)-13, as well as IL-4, causes de novo surface expression of vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells of the umbilical vein and accelerates selective eosinophil migration. However, its role in allergic rhinitis remains to be clarified. Of particular interest is whether IL-13 upregulates VCAM-1 expression in human mucosal microvascular endothelial cells (HMMECs), to which eosinophils adhere in nasal mucosa.

METHODS

To understand the potential role of IL-13 in eosinophilic inflammation in nasal mucosa, we examined the effects of IL-13 on the adhesiveness between HMMECs and eosinophils.

RESULTS

IL-13 increased VCAM-1 expression in HMMECs, the adhesiveness of endothelial cells to eosinophils, and the transendothelial migration. On the other hand, IL-13 decreased the adhesiveness of eosinophils to HMMECs, and, as a result, accelerated eosinophil infiltration. Those effects are more potent than was those of IL-4. In addition, we also report that the amount of IL-13 in nasal mucosa was higher than that of IL-4.

CONCLUSIONS

These results strongly indicate that IL-13, as well as IL-4, may be important in eosinophilic inflammation in the nasal mucosa.

Late phase response in nasal mucosa closely correlated with immediate phase reaction and hyperreactivity to histamine

It has been suggested that the onset of the late phase response (LPR) and hyperreactivity to non-specific stimuli occurs in the lower airway. However, its relationship in the nose has not yet been studied. This study was designed to examine the mechanism of LPR and the relationship between LPR and hyperreactivity. A total of 25 Japanese cedar pollinosis patients participated in this study. On the first visit, the frequency of sneezes, weight of nasal discharge, and the nasal airway resistance (NAR) were time-dependently measured without antigen challenge. The histamine reactivity was observed after 12 h. The same protocol was used during the second to fourth visits. The frequency of sneezes, weight of nasal discharge, and NAR were measured continuously for 12 h after antigen challenge, and nasal reactivity to histamine was observed. The percent change of NAR during immediate phase response (IR) and during LPR showed a significant correlation. The frequency of sneezes and weight of nasal discharge induced by histamine were both significantly higher in the positive than in the negative LPR group. These results suggest that the chemical mediators and inflammatory cells inducing nasal swelling during IR cause, directly or indirectly, nasal swelling during LPR, and induce hyperreactivity to histamine.

Decrease in gamma-actin expression, disruption of actin microfilaments and alterations in cell adhesion systems associated with acquisition of metastatic capacity in human salivary gland adenocarcinoma cell clones

In order to clarify how cytoskeletons and adhesion systems change through acquisition of metastatic capacity in a cancer cell, we examined the expressions of beta- and gamma-actin, the morphology of actin microfilaments and focal contacts, and also the expression of vinculin in a salivary gland adenocarcinoma cell clone cl-1, which acquired metastatic capacity, in comparison with its original clone HSGc lacking metastatic ability. Two-dimensional gel electrophoresis of Triton-insoluble fractions and combined Western blot analysis by immunostaining with anti actin-isoform antibodies showed that the expression of gamma-actin was somewhat lower than that of beta-actin in HSGc, and cl-1 expressed a comparable amount of beta-actin to HSGc, whereas gamma-actin expression by cl-1 was far less than that by HSGc. Northern blot analysis demonstrated that there was little difference in the level of beta-actin mRNA between HSGc and cl-1, while the level of gamma-actin was markedly decreased in cl-1 as compared with HSGc. In terms of morphology, cl-1 cells showed disruption of actin microfilaments and a decrease in the size and number of focal contacts on the cell surface. Furthermore, cl-1 showed decreased expression of vinculin, which became obscured even at the end of actin microfilaments. These results demonstrated that a decrease in gamma-actin, disruption of actin microfilaments, and suppression of focal contacts as well as vinculin take place in the transformation from a non-metastatic condition to a metastatic one in the human salivary gland adenocarcinoma cell clones. Thus, it was strongly suggested that these changes contribute to a decrease in cell adhesiveness and an increase in cell motility, which is probably a major cause for acquisition of metastatic potential.

Comparison of static mechanical properties of the passive pharynx between normal children and children with sleep-disordered breathing

Collapsibility of the active pharynx, where active contraction of the upper airway muscles is evident, was previously reported to be higher in children with obstructive sleep apnea (OSA) than in those with primary snoring during sleep. Contribution of neuromuscular and anatomic factors to the increased collapsibility, however, was not estimated. We therefore evaluated collapsibility of the passive pharynx, in which upper airway muscle activities were eliminated. Our aim in the present study was to test the hypothesis that children with sleep-disordered breathing (SDB) have a structurally narrowed and a more collapsible pharynx compared with normal children. The static pressure/area relationship of the passive pharynx was endoscopically quantified in 14 children with SDB and in 13 normal children under general anesthesia with complete paralysis. The majority of children with SDB primarily closed their airways at levels of enlarged adenoids and tonsils with positive closing pressure (Pclose) (3.5+/-4.3 cm H2O), whereas half of the normal children closed their airways at the soft palate edges and the other half at the tongue bases with subatmospheric Pclose (-7.4+/-4.9 cm H2O). Cross-sectional area of the narrowest segment was significantly smaller in SDB children than in normal children. Interestingly, collapsibility of the retropalatal and retroglossal segments significantly increased in SDB children, compared with the normal subjects. We conclude that anatomic factors play a significant role in the pathogenesis of pediatric OSA and that predisposing structural abnormalities of the entire pharynx are likely to contribute to manifestation of OSA in addition to enlarged adenoids and tonsils.

Exchangeability of actin in cardiac myocytes and fibroblasts as determined by fluorescence photobleaching recovery

Rhodamine (Rho)-labeled muscle and non-muscle actins were microinjected into cultured embryonic chicken cardiac myocytes and fibroblasts. After incorporation of the fluorescent actin analog into cellular structures, small areas of labeled structures were photobleached with a laser pulse, and fluorescence recovery (FR) was measured to determine the exchangeability of isoactins in these structures. With both Rho-muscle and Rho-non-muscle actins, the FR rate in any part of stress fibers was consistently faster than that observed in any part of myofibrils. Thus, although non-striated (proximal and terminal) portions of nascent myofibrils are similar in appearance and composition to stress fibers, our data clearly revealed differences in actin stability between these two structures. Further, although cardiomyocytes were incapable of discriminating between the incorporation of muscle and non-muscle actin isoforms into myofibrils, FR after photobleaching of Rho-muscle actin was faster than that of Rho-non-muscle actin in immature non-striated portions. This indicates that actin molecules in cardiac myofibrils cannot be readily exchanged by heterotypic non-muscle actin. Fluorescently labeled actin incorporated into non-striated (proximal and terminal) portions of myofibrils and terminal portions of stress fibers was found to be more stable than alpha-actinin. The relative stability of actin could facilitate the formation of nascent Z-bands of myofibrils and the reorganization of stress fibers at these portions.