Innate immune reactions in locally limited tonsillar cancer.

Tonsillar cancers often present as locally limited tumors but with cervical metastases. When the primary tumors of tonsillar cancers with cervical metastases are as small as clinically occult, the clinical features are diagnosed as primary-unknown cervical metastases. However, little is known as to why small tonsillar cancers establish cervical metastases. The aim of this study was to investigate a possibility that innate immune reactions might suppress the growth of tumors arising in the palatine tonsils, because the palatine tonsils contain various immune effector cells. Infiltration of natural killer (NK) cells and macrophages, which are major innate immune cells, in surgically removed tumors from patients with locally limited tonsillar cancers and tongue cancers was immunohistochemically studied by using anti-CD57 and anti-CD68 antibodies. Phagocytosis of the tumor cells by macrophages was also studied by dual immunofluorescence labeling. The number of infiltrating CD57+ NK cells and CD68+ macrophages was significantly increased in locally limited tonsillar cancers in comparison to normal tonsils and tongue cancers. The phagocytosis of tumor cells by CD68+ macrophages was observed significantly more frequently in tonsillar cancers than in tongue cancers. These results indicated that the innate immune reactions were more strongly induced in locally limited tonsillar cancers than in tongue cancers, and might therefore suppress the growth of primary tumors in palatine tonsils. The innate immune reactions against cancers in palatine tonsils were suggested to be one of the possible etiologies for the developing of primary-unknown cervical metastases.

Age-related changes in the hyoepiglottic ligament: functional implications based on histopathologic study.

PURPOSE: The study aimed to identify age-related changes in the hyoepiglottic ligament associated with function of the epiglottis during swallowing and respiration. MATERIALS AND METHODS: Normal postmortem laryngeal tissue samples were obtained at autopsy from 20 individuals with no history of laryngeal disease. The subjects were divided into 2 groups: those aged 81-91 years (elderly group, n = 11) and those aged 31-48 years (non-elderly group, n = 9). Specimens were subjected to Elastica van Gieson and hematoxylin-eosin staining, and characteristics of the hyoepiglottic ligament were compared between groups. RESULTS: The hyoepiglottic ligament extended from the epiglottis to both lingual muscles and the hyoid bone (pars lingualis and pars hyoideus). The numbers of muscle fibers (P < .001), collagenous fibers (P < .01), and elastic fibers (P < .001) were significantly decreased in the elderly group in comparison to those in the non-elderly group. CONCLUSION: Age-related changes in the hyoepiglottic ligament appear to be associated with aspiration, obstructive sleep apnea syndrome, and acquired laryngomalacia in the elderly.

Coccoid Helicobacter pylori exists in the palatine tonsils of patients with IgA nephropathy.

PURPOSE: Helicobacter pylori infection is acquired by oral ingestion. H. pylori has been reported to be present in the palatine tonsils. To clarify the route and mode of infection, the prevalence of tonsillar H. pylori was evaluated, and an attempt was made to culture tonsillar H. pylori. METHODS: In a prospective study, 55 patients with recurrent pharyngotonsillitis or IgA nephropathy underwent a tonsillectomy. The carbon 13-urea breath test and enzyme-linked immunosorbent assay for the detection of H. pylori IgG antibodies in the serum were performed. Tonsillar H. pylori was cultured under conventional culture conditions for gastric H. pylori with or without the following shock methods; heat shock, hydrogen-peroxide-degrading compounds, or parasitizing amoebae. Immunofluorescence and immunoelectron microscopy using antibodies against H. pylori and cytotoxin-associated antigen A were used to identify tonsillar H. pylori. RESULTS: H. pylori in the coccoid form was present in tonsillar crypts. Of 55 patients, 43 (78.2%) had tonsillar H. pylori, and 15 (27.3%) were infected with gastric H. pylori. All patients with gastric H. pylori also had tonsillar H. pylori (p < 0.01). Cytotoxin-associated antigen A was observed in 38 (88.4%) of 43 tonsillar H. pylori. Tonsillar H. pylori could not be cultured in any culture conditions. All patients with IgA nephropathy had tonsillar H. pylori (p < 0.01). CONCLUSIONS: The present research might provide some insight into clarifying the route and mode of H. pylori infection. Our findings may indicate that tonsillar H. pylori is one of the antigens causative of IgAN.

Mutant FGF23 prevents the progression of chronic kidney disease but aggravates renal osteodystrophy in uremic rats.

Phosphorus is one of the important factors that accelerate the progression of chronic kidney disease. Phosphorus restriction or phosphate binders have been reported to have the ability to prevent the progression of chronic kidney disease. FGF23 is a circulating factor that regulates renal phosphorus reabsorption and 1 alpha-hydroxylase activity. We focused on the phosphaturic activity of FGF23 and investigated whether a pharmacological dose of FGF23 is beneficial to the progression of renal insufficiency in uremic rats. To this end, we administered one of the mutant FGF23 expression plasmids into irreversible Thy1 rats. Chronic renal failure rats were established by intravenous injection of anti-rat CD90 (Thy1.1) monoclonal antibody to unilaterally nephrectomized Wistar rats. The rats were then intravenously injected every 2 wk with a naked DNA solution containing 10 microg of MOCK vector or a mutant FGF23 expression plasmid for 13 wk. Renal function was assessed biochemically and histopathologically. Mutant FGF23 significantly decreased serum creatinine and serum urea nitrogen. The marked glomerular sclerosis observed in uremic rats receiving the MOCK vector was ameliorated in rats treated with mutant FGF23. However, mutant FGF23 not only significantly decreased serum 1,25(OH)(2)D and calcium but also aggravated high-turnover renal osteodystrophy from extremely high levels of PTH. These results might be a result of the mechanisms of FGF23 such as phosphaturic activity and lowering the level of 1,25(OH)(2)D. In conclusion, mutant FGF23 prevented the progression of chronic renal failure by regulating serum phosphorus but aggravated renal osteodystrophy from the lowered levels of 1,25(OH)(2)D.

Active neovascularization and possible vascular-centric development of gastric and periscapular elastofibromas.

An elastofibroma is a benign and rare fibrous lesion that most commonly occurs in the periscapular region. A gastrointestinal elastofibroma is extremely rare. In the present study, six cases of elastofibromas including a case in the stomach were evaluated. The gastric case revealed widely distributed lesions in the submucosal layer with perivascular fibrotic lesions (PVFLs) and some PVFLs were distributed to the skip lesions of elastofibroma. These PVFLs were also observed in all five periscapular cases and invariably contained elastic fibers which showed various degree of maturation. CD34-positive stromal cells were observed not only in elastofibromas but also in PVFLs in each case. These findings suggested the possibility of the PVFLs were the primary lesions of elastofibroma and their vascular-centric development. The percentage of the CD105-positive vessels in elastofibroma group was significantly higher than in the control group. This result indicates active neovascularization in elastofibromas.

Histological changes of the pharynx and larynx in rats with chronic acid reflux esophagitis.

CONCLUSIONS: The histological changes of the pharynx and the larynx associated with surgically induced chronic acid reflux esophagitis were observed in rats. Chronic inflammatory change due to gastric acid reflux was found microscopically in the pharynx and larynx. This indicated that inflammatory changes due to gastric acid reflux are associated with the pathogenesis of laryngopharyngeal reflux disease (LPRD). OBJECTIVE: To clarify the pathological mechanism of LPRD by studying the histological changes of the pharynx and the larynx in rats with chronic acid reflux esophagitis. MATERIALS AND METHODS: An experimental rat model of chronic acid reflux esophagitis was created surgically. The pharynx, larynx, trachea, lung, and esophagus of these rats were observed histologically every 2 weeks until 20 weeks after the operation. RESULTS: At 8 weeks after the operation, mucosal thickening and inflammatory cell infiltration were observed in the hypopharynx of the rat model. Moreover, chronic inflammation with proliferation of fibroblasts, deposition of collagen fibers, and proliferation and dilatation of the capillaries were found as time progressed. However, little macroscopic change was observed in the hypopharyngeal mucosa. In addition, at 16 weeks post-operation, inflammatory cell infiltration was identified in the nerve cells around the thoracic esophagus, the arytenoid region, and the lung.

Role of low protein and low phosphorus diet in the progression of chronic kidney disease in uremic rats.

Restriction of dietary protein is useful for chronic kidney disease (CKD) patients to protect residual renal function. However, the mechanism by which a low protein diet confers a beneficial effect in CKD patients remains unknown. One possibility is that the benefit from a low protein diet is associated with phosphorus restriction. The aim of this study is to compare the effect of protein and phosphorus on the progression of renal insufficiency using irreversible Thy1 rats, which histopathologically resemble IgA nephropathy. Irreversible Thy1 rats were fed six types of isocaloric diets consisting of three levels of protein (16.9, 12.6, and 8.4%) and two levels of phosphorus (0.5 and 0.3%) for 13 wk. Renal function was assessed biochemically and histopathologically. The low phosphorus (0.3%) diets showed protection of residual renal function regardless of dietary protein content in uremic rats. With the normal phosphorus (0.5%) diets, however, only the very low protein (8.4%) diet showed a beneficial effect, indicating that dietary phosphorus is a more important factor that affects the progression of renal insufficiency than dietary protein in this model. Furthermore, the low phosphorus diet also prevented an increase in serum parathyroid hormone, indicating that a low phosphorus diet might have beneficial effects not only for residual renal function but also for renal osteodystrophy, a typical complication of patients with CKD.

Helicobacter pylori in the palatine tonsils of patients with IgA nephropathy compared with those of patients with recurrent pharyngotonsillitis.

Helicobacter pylori infection is acquired by oral ingestion. However, the morphology and microscopic localization of H pylori in the human oral cavity and pharynx are unknown. In the present study, we performed immunohistochemistry, immunoelectron microscopy, in situ hybridization, and polymerase chain reaction to identify H pylori in the palatine tonsils of 32 patients with immunoglobulin A nephropathy (IgAN) and 141 patients with recurrent pharyngotonsillitis (RPT). H pylori in coccoid form was present in bacterial colonies and horny layers of the stratified squamous epithelium in tonsillar crypts. We described for the first time the morphology of H pylori in palatine tonsils. Most bacterial colonies were sulfur granules with Actinomyces israelii (A israelii), and A israelii showed significant coexistence with H pylori (P=.011). The prevalence of H pylori in palatine tonsils of the RPT group increased steeply with age, but one fourth of the patients were found not to have tonsillar H pylori in adulthood. All patients with IgAN had H pylori in palatine tonsils. The prevalence of H pylori was greater in the IgAN group than in the RPT group, and the difference was statistically significant (P<.001). In contrast, A israelii was unrelated to age and clinical diagnosis (P=.722). In conclusion, our results demonstrate that H pylori in coccoid form is present in palatine tonsils and may indicate that H pylori in palatine tonsils is among the antigens causative of IgAN.

Olfactory neuroepithelioma: an immunohistochemical and ultrastructural study.

Three cases of olfactory neuroepithelioma are presented in this report. Histologically, these tumors were composed of small cells with round to oval, relatively hyperchromatic nuclei and scanty cytoplasm. The tumor cells were occasionally observed in tubular formations or rosette-like arrangements. Immunohistochemically, the tumor cells showed a positive reaction for cytokeratin AE1, cytokeratin CAM5.2, Ber-EP4, antisynaptophysin and anti-S100 protein in all cases. In two cases, LH-RH was detected in the tumor cells. Ultrastructurally, the tumor cells had the differentiation features of olfactory epithelium. Olfactory neuroepithelioma is a rare occurrence and it can be very difficult to distinguish olfactory neuroepithelioma from small cell carcinoma, neuroendocrine carcinoma and so-called "olfactory neuroblastoma" on the basis of hematoxylin and eosin stained sections alone. In controversial cases, a diagnosis of olfactory neuroepithelioma must be substantiated by ultrastructural and immunohistochemical findings, particularly regarding the detection of Ber-EP4 and LH-RH immunoreactivity.

Role of the vitamin D receptor in FGF23 action on phosphate metabolism.

FGF23 (fibroblast growth factor 23) is a novel phosphaturic factor that influences vitamin D metabolism and renal re-absorption of Pi. The goal of the present study was to characterize the role of the VDR (vitamin D receptor) in FGF23 action using VDR(-/-) (VDR null) mice. Injection of FGF23M (naked DNA encoding the R179Q mutant of human FGF23) into VDR(-/-) and wildtype VDR(+/+) mice resulted in an elevation in serum FGF23 levels, but had no effect on serum calcium or parathyroid hormone levels. In contrast, injection of FGF23M resulted in significant decreases in serum Pi levels, renal Na/Pi co-transport activity and type II transporter protein levels in both groups when compared with controls injected with mock vector or with FGFWT (naked DNA encoding wild-type human FGF23). Injection of FGF23M resulted in a decrease in 25-hydroxyvitamin D 1a-hydroxylase mRNA levels in VDR(-/-) and VDR(+/+) mice, while 25-hydroxyvitamin D 24-hydroxylase mRNA levels were significantly increased in FGF23M-treated animals compared with mock vector control- or FGF23WT-treated animals. The degree of 24-hydroxylase induction by FGF23M was dependent on the VDR, since FGF23M significantly reduced the levels of serum 1,25(OH)2D3 [1,25-hydroxyvitamin D3] in VDR(+/+) mice, but not in VDR(-/-) mice. We conclude that FGF23 reduces renal Pi transport and 25-hydroxyvitamin D 1a-hydroxylase levels by a mechanism that is independent of the VDR. In contrast, the induction of 25-hydroxyvitamin D 24-hydroxylase and the reduction of serum 1,25(OH)2D3 levels induced by FGF23 are dependent on the VDR.

Circulating FGF-23 is regulated by 1alpha,25-dihydroxyvitamin D3 and phosphorus in vivo.

Fibroblast growth factor-23 (FGF-23), a novel phosphate-regulating factor, was elevated in hypophosphatemic patients with X-linked hypophosphatemic rickets/osteomalacia and also in patients with chronic kidney disease. These observations suggested the pathophysiological importance of FGF-23 on phosphate homeostasis. However, regulation of FGF-23 production is still unclear. We investigated effects of both dietary phosphorus and 1alpha,25-dihydroxyvitamin D(3) (1alpha,25(OH)(2)D(3)) on circulating FGF-23 in vivo Administration of. 1alpha,25(OH)(2)D(3) dose-dependently increased serum FGF-23 in thyroparathyroidectomized rats without correlating with serum inorganic phosphorus or serum parathyroid hormone. On the other hand, vitamin D receptor null mice had very low serum FGF-23 and did not respond to the 1alpha,25(OH)(2)D(3) administration. These observations suggested 1alpha,25(OH)(2)D(3) directly or indirectly regulates circulating FGF-23. Serum FGF-23 had a strong correlation with serum inorganic phosphorus controlled by dietary phosphorus in 5/6 nephrectomized rats. High phosphate diet elicited a 5-fold increase in serum FGF-23 compared with sham-operated rats, whereas serum FGF-23 did not correlate with serum calcium or serum creatinine in 5/6 nephrectomized rats. Administration of 1alpha,25-dihydroxyvitamin D(3) also elicited a severalfold increase in serum FGF-23 in the uremic rats. Taken together, this shows that both serum phosphorus and 1alpha,25(OH)(2)D(3) regulate circulating FGF-23 independent of each other. Therefore, we proposed there was a feedback loop existing among serum phosphorus, 1alpha,25(OH)(2)D(3), and FGF-23, in which the novel phosphate-regulating bone-kidney axis integrated with the parathyroid hormone-vitamin D(3) axis in regulating phosphate homeostasis.

Effect of hydrolysis-resistant FGF23-R179Q on dietary phosphate regulation of the renal type-II Na/Pi transporter.

Fibroblast growth factor 23 (FGF23), a phosphaturic factor, is involved in the regulation of renal inorganic phosphate (Pi) reabsorption. Proteolysis-resistant FGF23 mutants expressed in rodents reduce Pi uptake in both intestine and kidney, independent of parathyroid hormone action. In the present study, we investigated whether FGF23 affects dietary regulation of Na(+)-dependent Pi (Na/Pi) cotransport in the rat kidney using wild-type FGF23 and an R179Q mutant, which disrupts a consensus proteolytic cleavage motif. Rats injected with naked human FGF23 DNA (wild-type or R179Q mutant) expressed the human FGF23 transcript in the liver. In those animals, plasma calcium and parathyroid hormone levels were not affected by FGF23 (either wild-type or R179Q mutant). FGF23-R179Q did, however, significantly decrease plasma Pi and renal Na/Pi cotransport activity and also the level of type-IIc Na/Pi cotransporter protein in brush-border membrane vesicles (BBMVs) from normal rat kidney. Western blot and immunohistochemical analyses in rats fed a low-Pi diet showed the levels of types-IIa and -IIc Na/Pi cotransporters to be markedly increased. After injection of FGF23-R179Q DNA into the rats fed a low-Pi diet, the levels of the types-IIa and -IIc transporter proteins were decreased. The FGF23 mutant thus blunts the signalling of Pi deprivation to the renal type-II Na/Pi cotransporter, suggesting that the FGF23 pathway could be involved in the signalling of dietary Pi.

Sevelamer hydrochloride prevents ectopic calcification and renal osteodystrophy in chronic renal failure rats.

BACKGROUND: Hyperphosphatemia is associated with severe complications, including ectopic calcification of soft tissues, secondary hyperparathyroidism, and renal osteodystrophy (ROD). Sevelamer hydrochloride is a nonabsorbed calcium- and metal-free phosphate binder that lowers serum phosphorus levels in hemodialysis patients. This study examined the efficacy of sevelamer in preventing ectopic calcification of soft tissues and ROD in adenine-induced renal failure rats. METHODS: Male, 12-week-old Wistar-Jcl rats were freely fed an adenine diet (0.75 g adenine in 100 g normal diet) for four weeks. After three weeks of the adenine diet, when serum phosphorus levels had significantly increased, the rats were freely fed a normal diet that contained 1% or 2% of sevelamer for another five weeks. Time course changes of serum levels of phosphorus, calcium, and parathyroid hormone (PTH) were measured. At the end of the study, calcium and phosphorus levels in the heart and aorta were measured, and the calcification of kidney, heart, aorta, and stomach were histopathologically examined. The severity of ROD was evaluated by a histopathologic and morphometric analysis of the femurs. RESULTS: Compared with the adenine controls (N = 10), the sevelamer-treated (1%, N = 6; and 2%, N = 10) groups of adenine-induced renal failure rats had reduced serum phosphorus, serum calcium x phosphorus product, and serum PTH levels. Moreover, in the treatment groups, sevelamer suppressed calcification of the aorta media, and also the osteoid volume, fibrosis volume, and porosity ratio of femurs. CONCLUSION: These results suggest that sevelamer treatment might contribute to the suppression of ectopic calcification and ROD.

Human fibroblast growth factor-23 mutants suppress Na+-dependent phosphate co-transport activity and 1alpha,25-dihydroxyvitamin D3 production.

The human fibroblast growth factor 23 (hFGF23) and its autosomal dominant hypophosphatemic rickets (ADHR) mutant genes were incorporated into animals by naked DNA injection to investigate the action on phosphate homeostasis in vivo. The hFGF23 mutants (R176Q, R179Q, and R179W) markedly reduced serum phosphorus (6.2-6.9 mg/dl) compared with the plasmid MOCK (8.5 mg/dl). However, native hFGF23 did not affect serum phosphorus (8.6 mg/dl). Both hFGF23 and hFGF23R179Q mRNAs were expressed more than 100-fold in the liver 4 days after injection, however, the C-terminal portion of hFGF23 was detected only in the serum from hFGF23R179Q-injected animals (1109 pg/ml). hFGF23R179Q mutant was secreted as a 32-kDa protein, whereas, native hFGF23 was detected as a 20-kDa protein in the cell-conditioned media. These results suggest the hFGF23R179Q protein is resistant to intracellular proteolytic processing. The hFGF23R179Q suppressed Na/P(i) co-transport activities both in kidney and in small intestine by 45 and 30%, respectively, as well as serum 1alpha,25-dihydroxyvitamin D(3) to less than 15 pg/ml. However, it had little effect on serum parathyroid hormone (PTH). Infusion of hFGF23R179Q protein normalized serum phosphorus in thyroparathyroidectomized rats without affecting serum calcium. Taken together, the FGF23 mutants reduce both phosphate uptake in intestine and phosphate reabsorption in kidney, independent of PTH action.

22-Oxacalcitriol prevents progressive glomerulosclerosis without adversely affecting calcium and phosphorus metabolism in subtotally nephrectomized rats.

BACKGROUND: 22-Oxacalcitriol (OCT), an analogue of vitamin D, has been shown to inhibit cell proliferation in cultured mesangial cells. OCT also prevented albuminuria and glomerular injury in an acute model of anti-Thy1 glomerulonephritis. However, potential side effects, including calcaemic actions and tubular dysfunction, of chronic OCT treatment remain unclear. In the present study, we evaluated the effect of OCT in a chronic model of progressive glomerulosclerosis in subtotally nephrectomized (SNX) rats. METHODS: At one week after subtotal nephrectomy, SNX rats were divided into 3 groups having equivalent serum creatinine levels and body weight. OCT (0.08 or 0.4 micro g/kg body weight) was administered intravenously three times per week for 8 weeks to SNX rats. We evaluated effects of OCT on renal function during treatment and on morphologic parameters in glomeruli at 8 weeks. We additionally measured calcium and phosphate levels in serum and urine, and tubular dysfunction markers, including beta(2)-microgloblin (beta(2)m) and N-acetyl-beta-D-glycosaminidase (NAG) levels in urine. RESULTS: OCT treatment significantly suppressed urinary albumin excretion, prevented increases in serum creatinine and serum urea nitrogen, and inhibited glomerular cell number, glomerulosclerosis ratio and glomerular volume in SNX rats at 8 weeks. At that time, OCT-treated groups did not show hypercalcaemia, hypercalciuria or hyperphosphaturia. Furthermore, OCT treatment did not affect beta(2)m or NAG levels in urine, and did not induce histological changes in tubular or interstitial regions. CONCLUSIONS: These findings suggest that OCT may provide a clinically useful agent for preventing the progression of glomerulosclerosis without adversely affecting calcium and phosphorus metabolism or causing subsequent tubular dysfunction.