Fc-Gamma Receptor Polymorphisms Predispose Patients to Infectious Complications After Liver Transplantation.

We investigated the impact of polymorphisms in host innate immunoregulatory genes on the development of infectious complications after liver transplantation (LT). The single-nucleotide polymorphisms (SNPs) of C1QA [276A/G], FCGR2A [131H/R], and FCGR3A [158F/V], genes encoding the Fc gamma receptor (FcγR), were analyzed in 89 living donor LT recipients in relation to the occurrences of postoperative infectious complications within 30 days after LT. Consistent with a lower affinity of the isoform encoded by FCGR3A [158F] to both IgG1 and IgG3, a significantly higher incidence of bloodstream infections (BSI) was observed in the FCGR3A [158F/V or F/F] than in the FCGR3A [158V/V] individuals. The combination of FCGR2A and FCGR3A SNPs further stratified the incidence of BSI, regardless of C1QA SNP. The predominant causative pathogen of BSI in the FCGR3A [158F/F or F/V] patients was gram-positive cocci (73.3%), of which one third was methicillin-resistant Staphylococcus aureus. No differences were observed in the incidence of fungal infections or in cytomegalovirus infections with respect to the three gene polymorphisms. Our findings indicate that FcγR SNPs are predisposing factors for BSI and can predict mortality after LT. This study provides a foundation for further prospective studies on a larger scale.

Safety of pre-engraftment prophylactic foscarnet administration after allogeneic stem cell transplantation.

Human herpesvirus-6 (HHV-6) is a major cause of limbic encephalitis with a dismal prognosis after allogeneic hematopoietic stem cell transplantation (SCT). Because our previous trial of preemptive therapy with foscarnet sodium (phosphonoformic acid; PFA) failed to prevent HHV-6 encephalitis, we conducted a prospective study to examine the safety of prophylactic PFA administration and elucidate the changes in the plasma HHV-6 DNA levels in the early post-SCT period. Plasma HHV-6 DNA was measured thrice weekly from day 6. PFA, 90 mg/kg/day, was administered from days 7 to 21 after bone marrow or peripheral blood SCT and to day 25 after umbilical cord blood transplantation. Of the 10 patients enrolled, 2 dropped out of the study, 1 because of early death, and 1 with a low glomerular filtration rate. Grade 3 or greater adverse events occurred in 9 of the 10 prophylactic PFA patients and in 7 of the 10 control patients who had clinical backgrounds similar to the study subjects and underwent SCT during the same period. Neurological disorders developed in none of the study subjects but in 4 of the 10 control patients, including 2 with HHV-6 encephalitis. HHV-6 reactivation occurred in 3 of the 10 study subjects. The prophylactic PFA regimen was thus safe and it may reduce the risk of limbic encephalitis, but is not considered to be potent enough to prevent HHV-6 reactivation.

Successful treatment of Trichosporon fungemia in a patient with refractory acute myeloid leukemia using voriconazole combined with liposomal amphotericin B.

Trichosporon fungemia is a rare and fatal fungal infection that occurs in patients with prolonged neutropenia associated with hematologic malignancies. A 21-year-old male developed Trichosporon fungemia during remission induction therapy for acute myeloid leukemia (AML). Although two courses of induction therapy failed to induce a remission of AML, combination therapy with voriconazole and liposomal amphotericin B (L-AmB) followed by monocyte colony-stimulating factor ameliorated the Trichosporon fungemia and enabled the patient to receive reduced-intensity bone marrow transplantation (BMT) from his human leukocyte antigen-A one-locus mismatched mother. The patient achieved a durable remission after BMT without exacerbation of Trichosporon fungemia. The combination therapy with voriconazole and L-AmB may therefore be useful in controlling Trichosporon fungemia associated with prolonged neutropenia after remission induction therapy for AML.

mRNA of the pro-apoptotic gene BBC3 serves as a molecular marker for TNF-α-induced islet damage in humans.

AIMS/HYPOTHESIS: TNF-α plays important roles in the pathogenesis of type 1 and type 2 diabetes mellitus. In light of this, we examined the involvement of a pro-apoptotic gene, BBC3 (also known as PUMA), in TNF-α-mediated beta cell dysfunction and destruction in human islets. METHODS: Human islets were exposed in vitro to TNF-α alone or in combination with IFN-γ. Gene expression was assessed by RT-PCR using a set of single islets. Protein abundance and cellular localisation of BBC3 were assessed by immunoblot and immunohistochemistry. A marginal number of islets were transplanted into diabetic NODscid mice to correlate in vivo islet function with BBC3 expression. RESULTS: BBC3 and IL8 mRNA were upregulated in TNF-α-stimulated islets in a dose-dependent manner and enhanced through addition of IFN-γ, but not upregulated by IFN-γ alone. Immunohistochemistry revealed that TNF-α in combination with IFN-γ upregulated basal BBC3 abundance in the cytoplasm of beta cells along with the perinuclear clustering of mitochondria partially co-localised with BBC3. TNF-α alone did not induce beta cell death, but did abrogate preproinsulin precursor mRNA synthesis in response to high glucose stimulation, which was inversely associated with upregulation of BBC3 mRNA expression by TNF-α. Higher BBC3 mRNA expression in islets correlated with decreased graft function in vivo. CONCLUSIONS/INTERPRETATION: These results suggest that BBC3 mRNA can serve as a molecular marker to detect early TNF-α-induced beta cell stress and may help identify islet-protective compounds for the treatment of diabetes.

Memory-like Liver Natural Killer Cells are Responsible for Islet Destruction in Secondary Islet Transplantation.

We previously demonstrated the pivotal role of natural killer (NK) cells in islet graft loss during the early phase after intraportal syngeneic islet transplantation (IT). Liver-resident DX5- NK cells were reported to possess memory-like properties, distinguishing them from conventional DX5+ NK cells. Here, we investigated the impact of primary IT-induced liver DX5- NK cells on the engraftment of secondary-transplanted islets in mice. The culture of liver NK cells isolated from naive mice with TNF-α, IFN-γ, and IL-lß, mimicking instant blood-mediated inflammatory reaction, led to significantly increased DX5- NK cell percentage among total liver NK cells. Consistently, the prolonged expansion of DX5- CD69+ TRAIL+ CXCR3+ NK cells was observed after intraportal IT of 300 syngeneic islets (marginal mass). In most diabetic mice, 400 syngeneic islets of primary IT were sufficient to achieve normoglycaemia, whereas the same mass after secondary IT failed to induce normoglycaemia in mice that received 200 syngeneic islets during primary IT. These findings indicated that liver-resident DX5- NK cells significantly expanded even after syngeneic IT, and that these memory-like NK cells may target both originally engrafted and secondary-transplanted islets. Furthermore, anti-TNF-α treatment suppressed the expansion of liver-resident DX5- NK cells, resulting in successful islet engraftment after sequential ITs.

Inhibition of the formation of oral calcium phosphate precipitates: the possible effects of certain honeybee products.

BACKGROUND AND OBJECTIVE: We studied the effects of honeybee products on the in vitro formation of calcium phosphate precipitates. MATERIAL AND METHODS: Screening tests of the in vitro formation of calcium phosphate precipitates using 20 types of honey and four types of propolis were carried out using the pH drop method. RESULTS: The inhibitory effect on the rate of amorphous calcium phosphate transformation to hydroxyapatite and on the induction time varied greatly among the 20 types of honey and four types of propolis. We classified them according to their effects on decreasing the rate of amorphous calcium phosphate transformation to hydroxyapatite and/or increasing the induction time. Two of the 20 honeys showed little or no inhibition, either on the rate of amorphous calcium phosphate transformation to hydroxyapatite or on the induction time. Six of the honeys reduced the rate of amorphous calcium phosphate transformation to hydroxyapatite by 12-35% and with a 2.5- to 4.4-fold increase in the induction time. The remaining 12 honeys showed even greater activity. Because four of these 12 honeys had an inhibitory effect on the rate of amorphous calcium phosphate formation, they were excluded as candidates for anticalculus agents. Furthermore, three of the four types of propolis showed an inhibitory effect that was the same as or greater than 1-hydroxyethylidene- 1,1-bisphosphonate. CONCLUSION: These results suggest that eight honeys and three types of propolis may have potential as anticalculus agents in toothpastes and mouthwashes.

Role of Natural Killer Cells in the Innate Immune System After Intraportal Islet Transplantation in Mice.

BACKGROUND: Both liver natural killer (NK) and NK T cells of the innate immune system play a crucial role in islet graft loss after intraportal islet transplantation, although a relationship between NK and NK T cells in islet loss has not been proven. In this study, we investigated the role of NK cells in the innate immune system in islet graft loss after intraportal islet transplantation. METHODS: To investigate the involvement of liver NK cells in islet destruction, we assessed the differences in graft survival after intraportal islet transplantation between CD1d-/- diabetic mice and NK cell-depleted CD1d-/- diabetic mice. RESULTS: The transplantation of 400 islets into the liver was sufficient to reverse hyperglycemia in wild-type diabetic mice (100%, 4/4). However, normoglycemia could not be achieved when 200 islets were transplanted (0%, 0/4). In contrast, intraportal transplantation of 200 islets in NK cell-depleted CD1d-/- diabetic mice ameliorated hyperglycemia in 71% of cases (5/7), whereas transplantation of the same number of islets in CD1d-/- diabetic mice did not (0%, 0/4). Histologic findings also confirmed that intact islets were observed in NK cell-depleted CD1d-/- diabetic mice, but were difficult to observe in CD1d-/- diabetic mice. CONCLUSIONS: The involvement of liver NK cells in the innate immune system related to islet graft loss after intraportal islet transplantation is revealed by improved graft survival and function in NK cell-depleted CD1d-/- diabetic mice. Our data reveal that regulation of NK cell activity is particularly important when insufficient islet numbers are used for transplantation.

MELD and Child-Pugh Scores Are Related to Immune Status of Intrahepatic Natural Killer Cells in Liver Transplant Candidates.

BACKGROUND: The role and phenotypic alterations of intrahepatic natural killer (NK) cells in liver disease were investigated. Although intrahepatic NK cells reportedly functionally deteriorate in the fibrotic liver, it remains unclear how the clinical severity of liver disease affects intrahepatic NK cells in patients with advanced liver failure. METHODS: We analyzed the phenotypic properties of intrahepatic NK cells by using mononuclear cells extracted from ex vivo liver perfusate effluents from patients who underwent liver transplantation. The relationship between the clinical severity of liver disease and the phenotype of intrahepatic NK cells in these patients was also evaluated. To estimate the immunological responsiveness of intrahepatic NK cells, phenotypic enhancement after interleukin-2 stimulation was analyzed. RESULTS: Intrahepatic NK cells from patients with advanced liver failure exhibited down-regulated monomodal expression of NKp46, a major activating molecule. Notably, the expression level of NKp46 decreased depending on the severity of liver disease, Model for End-Stage Liver Disease score, and Child-Pugh score rather than the etiology. After in vitro recombinant interleukin-2 stimulation, the enhancement of expression of cytotoxic molecules, NKp44, and tumor necrosis factor-related apoptosis-inducing ligand was significantly impaired in intrahepatic NK cells from patients with liver failure, concurrently with decreased expression of CD122 and interleukin-2 receptor beta. CONCLUSIONS: Our results suggest that terminal deterioration of liver environments by chronic liver disease impairs the potential of local NK cells, depending on the severity of the deterioration. These influences of advanced liver failure on intrahepatic NK cells may be attributed to multicentric carcinogenesis in patients with liver failure.

Acute Graft Rejection and Formation of De Novo Donor-Specific Antibodies Triggered by Low Cyclosporine Levels and Interferon Therapy for Recurrent Hepatitis C Infection After Liver Transplantation: A Case Report.

BACKGROUND: We report a case of acute rejection of a liver graft, together with the occurrence of de novo donor-specific antibodies (DSAs), in a 53-year-old Japanese man who had undergone deceased-donor liver transplantation. METHODS: The graft rejection was triggered by low cyclosporine levels and pegylated interferon treatment for the recurrence of hepatitis C virus (HCV) infection 18 months after transplantation. Although the graft was ABO-compatible, pre-formed DSA B51 was detected; therefore, total plasma exchange was performed and intravenous rituximab (500 mg/body) was administered before transplantation. RESULTS: DSA was absent 6 months after transplantation. HCV recurrence was treated with pegylated interferon-α-2a. Renal function deteriorated with this anti-HCV therapy, with serum cyclosporine levels decreasing to 50 ng/mL. A rapid virologic response was achieved, but liver function deteriorated after 3 months of anti-HCV therapy, with histologic evidence of acute cellular rejection and formation of de novo DSAs. Anti-thymocyte globulin was administered for 5 days, which led to immediate improvement in liver function. However, renal function declined, warranting hemodialysis. The patient recovered 2 months after acute rejection, although de novo DSAs persisted. CONCLUSIONS: Careful immunologic monitoring may be required for patients receiving interferon therapy for HCV infection to maintain sufficient blood levels of immunosuppressive agents and to prevent acute liver graft rejection.

Principal component analysis uncovers cytomegalovirus-associated NK cell activation in Ph+ leukemia patients treated with dasatinib.

Dasatinib treatment markedly increases the number of large granular lymphocytes (LGLs) in a proportion of Ph+ leukemia patients, which associates with a better prognosis. The lymphocytosis is predominantly observed in cytomegalovirus (CMV)-seropositive patients, yet detectable CMV reactivation exists only in a small fraction of patients. Thus, etiology of the lymphocytosis still remains unclear. Here, we identified NK cells as the dominant LGLs expanding in dasatinib-treated patients, and applied principal component analysis (PCA) to an extensive panel of NK cell markers to explore underlying factors in NK cell activation. PCA displayed phenotypic divergence of NK cells that reflects CMV-associated differentiation and genetic differences, and the divergence was markedly augmented in CMV-seropositive dasatinib-treated patients. Notably, the CMV-associated highly differentiated status of NK cells was already observed at leukemia diagnosis, and was further enhanced after starting dasatinib in virtually all CMV-seropositive patients. Thus, the extensive characterization of NK cells by PCA strongly suggests that CMV is an essential factor in the NK cell activation, which progresses stepwise during leukemia and subsequent dasatinib treatment most likely by subclinical CMV reactivation. This study provides a rationale for the exploitation of CMV-associated NK cell activation for treatment of leukemias.

Reduced-intensity unrelated cord blood transplantation for treatment of metastatic renal cell carcinoma: first evidence of cord-blood-versus-solid-tumor effect.

We report a 69-year-old man with cytokine-resistant metastatic renal cell carcinoma treated with reduced-intensity unrelated cord blood transplantation. The patient achieved durable donor engraftment with minimal graft-versus-host disease. The patient showed regression of metastatic disease, providing the first evidence of a graft-versus-tumor effect on a solid tumor resulting from cord blood graft.

Inhibition of cancer cell growth by polyinosinic-polycytidylic acid/cationic liposome complex: a new biological activity.

A complex of polyinosinic-polycytidylic acid [poly(I) x poly(C)] and cationic liposome (LIC) inhibited the growth of many tumor cell lines at low concentration in vitro, but poly(I) x poly(C) alone had no such antiproliferative effect. The IC50 values of LIC against the tumor cells ranged from 0.1 to 1000 ng/ml. LIC had strong cytotoxic effects on malignant cells of epithelial and fibroblastic origin from various tissues and was also effective against Adriamycin-resistant tumor cells. LIC did not significantly affect the growth of lymphoma cells, leukemia cells, normal diploid fibroblasts, or primary liver cells at concentrations up to 10 microg/ml. The mechanism of the antiproliferative effect of LIC against malignant cells was the induction of apoptosis. LIC induced the fragmentation of nuclear DNA and the degradation of rRNA in tumor cells. The DNA fragmentation occurred within 1-5 h after the addition of LIC, and both the fragmentation and the inhibition of cancer-cell growth were suppressed by a nuclease inhibitor. In contrast, caspase inhibitors did not affect the antiproliferative activity of LIC. These results suggest that LIC induced apoptosis in malignant cells through the direct activation of nucleases and not through the activation of caspases. LIC reduced the incidence and the size of metastatic liver-cancer tumors in two different mouse metastatic liver-cancer models using human colon carcinoma cells. Histochemical analysis revealed that the KM12-HX cells in the tumor nodules were undergoing apoptosis; therefore, LIC also induced the apoptosis of tumor cells in vivo. In these animal models, LIC caused no observed changes in normal hepatocytes.

Two patients treated with simeprevir plus pegylated-interferon and ribavirin triple therapy for recurrent hepatitis C after living donor liver transplantation: case report.

We previously reported our data on telaprevir (TVR) used in combination with pegylated-interferon and ribavirin (PEG-IFN/RBV) for the treatment of recurrent hepatitis C virus (HCV) genotype 1 infection after liver transplantation (LT). TVR substantially increases the blood levels of immunosuppressive agents such as cyclosporine and tacrolimus for drug-drug interactions. On the other hand, the effect of simeprevir (SMV) on the blood levels of these immunosuppressive agents is unclear. We report 2 patients who achieved viral responses with little effect on the blood levels of cyclosporine and tacrolimus using SMV plus PEG-IFN/RBV treatment. The first was a 71-year-old woman with HCV-related liver cirrhosis and hepatocellular carcinoma who failed to respond to PEG-IFN/RBV after living donor LT. She was treated with 40 mg/d of cyclosporine, and received SMV plus PEG-IFN/RBV treatment. The second was a 65-year-old man with HCV-related liver cirrhosis who failed to respond to PEG-IFN/RBV after living donor LT. He was treated with 3 mg/d of tacrolimus, and received SMV plus PEG-IFN/RBV treatment. Serum HCV RNA became undetectable using TaqMan polymerase chain reaction (PCR) test after 4 weeks of treatment in both patients, and no remarkable fluctuation in blood concentration was observed either in cyclosporine or tacrolimus during the 12 weeks of SMV treatment. Completion of 12-week SMV triple therapy was followed by PEG-IFNα2b plus RBV, and both patients achieved sustained virological response 12 weeks after the end of treatment. SMV plus PEG-IFNRBV treatment showed a remarkable viral response with little effect on blood levels of immunosuppressive agents for recurrent HCV genotype 1 infection after LT.

Pancreatic endocrine function after total gastrectomy and truncal vagotomy.

Oral and intravenous glucose tolerance tests were performed in four groups: (1) preoperative patients, (2) patients with interposition reconstruction after total gastrectomy, (3) patients with Roux-Y reconstruction after total gastrectomy, and (4) patients with intrathoracic replacement after esophagectomy. We obtained the following results: (1) Hyperglucagonemia in response to orally administered glucose occurred after truncal vagotomy and occurred in the presence and absence of gastric tissue. (2) compared wtih the preoperative study, all postoperative groups demonstrated glucose intolerance. (3) The glucose intolerance was due to increased glucagon, insulinopenia, and possibly nutritional factors. (4) The insulin response to intravenous glucose suggests an impairment in the first phase of insulin secretion in the surgically treated group, demonstrating a role for the vagus in insulin secretion. (5) The glucose tolerance curve shows that the interposition operation is superior the the Roux-Y operation.

Clinical assessment of squamous cell carcinoma of the nasal cavity proper.

The subjects were 14 patients with squamous cell carcinoma or undifferentiated carcinoma of the nasal cavity treated at Nihon University Hospital between October 1984 and November 1991, who were followed for at least 3 years. The site of the tumor origin within the nasal cavity was the lateral wall in 8 patients, the nasal septum in three patients, and unknown in three patients. Histologically, there were 13 squamous cell carcinomas in (3 well differentiated, 7 moderately differentiated, and 3 poorly differentiated) and 1 undifferentiated carcinoma. Treatment was by a combination of radiotherapy, chemotherapy, and surgery in 8 cases, a combination of radiotherapy and surgery in 5 cases, and surgery alone in 1 case. The 3-year and 5-year Kaplan-Meier survival rates were 86 and 69%, respectively. A total of 6 patients suffered a recurrence, with local recurrence occurring in 4 patients and pulmonary metastasis in 2 patients. Tumor control was achieved in 3 of the 4 cases of local recurrence by reoperation, and by surgery in 1 of the 2 cases of pulmonary metastasis. The duration of the recurrence-free interval in the patients who developed local recurrences, 18 to 46 months after the completion of the initial course of therapy, was of considerable interest.

A case of abdominal aortic aneurysm associated with systemic lupus erythematosus.

A case of abdominal aortic aneurysm associated with systemic lupus erythematosus (SLE) is reported. A 45-year-old woman with a 18-year history of SLE was admitted with severe lumbago radiating to the bilateral inguinal region. CT and DSA showed a dumbbell shaped true aneurysm of the abdominal aorta. An aorto-biiliac Y shaped graft replacements was performed. SLE is rarely associated with aneurysm of the great arteries. We could find only 4 reports of abdominal aneurysm associated with SLE. Common features were the young age of the patient, the long term of the systemic disease, and administration of corticosteroid therapy for a relatively long period of time. We speculate that atherosclerosis, hypertension, and corticosteroid may all work in concert, possibly together with aortic wall involvement or vasculitic damage, to produce the rare abdominal aneurysm in SLE.

[A patient with Moyamoya-like vessels after radiation therapy for a tumor in the basal ganglia].

A patient with Moyamoya-like vessels after radiation therapy for treatment of a tumor in the basal ganglia is reported. He was diagnosed as Down syndrome at birth. He had a tumor in the left basal ganglionic region at 12 years of the age. The tumor increased in size at age 14. He underwent cerebral angiography, which did not show a stenosis nor occlusion of the internal carotid artery, anterior cerebral artery, nor the middle cerebral artery. He received radiation therapy with a total dose of 56 Gy. He presented a dressing apraxia at age 19. MRI showed cerebral infarction in the left temporo-occipital region. Right internal carotid angiography revealed a severe stenosis of the internal carotid artery and anterior cerebral artery as well as a severe stenosis of the middle cerebral artery on the right side. Moyamoya-like vessels were seen in the basal ganglionic region. Left internal carotid angiography also showed a stenosis of the internal carotid artery and anterior cerebral artery as well as a severe stenosis of the middle cerebral artery on the left side. Moyamoya-like vessels were seen in the basal ganglionic region. Leptomeningeal anastomose and transdural anastomose were bilaterally seen. These arterial occlusion and stenotic phenomenon corresponded to a previous radiation field. These Moyamoya-like vessels with arterial stenosis and occlusion were thought to be due to radiation-induced vasculopathy, because a previous cerebral angiography showed a normal caliber of cerebral arteries. This patient showed that patients with radiation therapy in their early childhood should be carefully observed considering the possibility of this phenomenon.

[A case of systemic sclerosis associated with interstitial pneumonia with various autoantibodies: improvement by intravenous cyclophosphamide therapy].

A 41-year-old woman was admitted to Tokyo Women's Medical College Aoyama Hospital in January 1994. She presented cough and dyspnea in September 1991. The diagnosis of interstitial pneumonia was made based on TBLB. Interstitial pneumonia was responsive to initial prednisolone of 40 mg daily. When dose of prednisolone was reduced to 15 mg daily, she complained of cough and dyspnea again. She was referred to Institute of Rheumatology, Tokyo Women's Maedical College in November 1993. She was diagnosed as systemic sclerosis associated with interstitial pneumonia based on proximal scleroderma and digital pitting scar. Double immunodiffusion and immunoprecipitation assay revealed the presence of anti-Ki, anti-Wa, and anti-RNA polymerases antibodies in the serum. On admission in March 1994, she was treated with intravenous cyclophosphamide therapy at 500 mg/day once a mouth. After the third infusion, respiratory symptoms, pulmonary function test values, findings of chest X-ray and CT scan were improved without adverse drug effects. Intravenous cyclophosphamide therapy seems to be useful in this case. The efficacy of Intravenous cyclophosphamide therapy in the treatment of the interstitial pneumonia associated with systemic sclerosis was discussed.

[An adult case of dermatomyositis complicated with cecum perforation and panniculitis].

The case of dermatomyositis complicated with cecum perforation and panniculitis occurred in a 62-year-old woman was reported. She was admitted to Keio University Hospital with a history of proximal muscular weakness, and dysphagia. Physical examination showed erythema over the face and shoulder. Serum level of muscle enzymes was remarkably increased. The diagnosis of dermatomyositis was made based on proximal muscular weakness, elevated serum level of muscle enzymes and myogenic change of electromyocardiogram. The treatment with 60 mg/day of prednisolone was started, and was a good response. However, 7 months later the disease became active again when the amount of prednisolone was reduced to 13 mg/day. Subsequently she complained of abdominal pain on the right lower quadrant. The surgical findings included peritonitis due to the perforation of the cecum and multiple ulcers of the cecum. After operation, azathioprine was added. Four years and 9 months later, she noticed skin erythema with ulceration and subcutaneous nodule. Skin biopsy indicated the findings of the panniculitis with membrano-cystic lesion. It was thought that both cecum perforation and panniculitis were caused by angiopathy which was often seen in childhood dermatomyositis.

[Ultrastructure and peculiarities of the otolith lagena in pigeons].

Rosenhall reported the polarization of kinocilium of otolith organs in the avian inner ear by LM. However, the otolith lagena, which is called the third otolith organ, is not well known, especially in terms of the 3-dimensional relationship between each maculae (utricular maculae, saccular maculae, maculae of the otolith lagena), the details of the striola and otoconial layers, and so on. Therefore, the author conducted a study to clarify these points using 20 Columba Domestica pigeons (40 ears), under the rules for animal experiments established by Nihon University School of Medicine. The pigeons were divided into 4 groups, 1. observations of the membranous labyrinth with binocular microscopes, 2. histological examination of serial sections of inner ear, 3. observations of the otolith lagena by SEM, 4. computer-aided 3-dimensional reconstruction of the membranous labyrinth. The following results were obtained. 1. the mean angle between the utricular maculae and maculae of the otolith lagena was 31 degrees (n = 3), the mean angle between the saccular maculae and maculae of the otolith lagena was 45 degrees (n = 3). 2. striola of the otolith lagena demonstrated a C form and the kinocilium exhibited an orientation identical to that of the striola of the outer saccular maculae, 3. the otolithic membrane of the otolith lagena demonstrated a mesh form and the otoconial layer was observed to be thin above the striola. 4. the surface area of the maculae of the otolith lagena was 0.98mm2 (n = 3) and the number of sensory cells was 16,800 (n = 3). The author also considered the functions of the otolith lagena.