Usefulness and problems of cytological examination by endobronchial ultrasound-guided transbronchial needle aspiration in the diagnosis of mediastinal lymphadenopathy: A retrospective single-centre study.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive and useful technique for sampling mediastinal lymph nodes. High sensitivity and specificity of EBUS-TBNA in staging lung cancer have been reported. However, few studies have addressed the results of EBUS-TBNA in the diagnosis of mediastinal lymphadenopathy with or without lung cancer, since various neoplastic and non-neoplastic conditions can involve the mediastinal lymph nodes. The present study analysed the results of the cytological examination of mediastinal lymphadenopathy using EBUS-TBNA in Kansai Medical University Hospital (Hirakata, Japan). A total of 41 consecutive patients with mediastinal lymphadenopathy who underwent EBUS-TBNA between January 2008 and December 2019 in Kansai Medical University Hospital were enrolled. This cohort included 29 males and 12 females. Cytological analyses demonstrated that 16/17 (94.1%) patients with metastatic carcinoma were diagnosed as having carcinoma (malignancy). The sensitivity, specificity and positive predictive value of the cytological examination in cases of carcinoma were 94.1, 100 and 100, respectively. However, only 3/11 (27.3%) patients with sarcoidosis were diagnosed by cytological examination. The present study demonstrated that EBUS-TBNA may be a useful method for detecting metastatic carcinoma in the mediastinal lymph nodes. However, the detection rate of epithelioid granuloma, which is a characteristic feature of sarcoidosis, was low in the present cohort. Hence, an improvement in the sampling technique is necessary.

Utility of an immunocytochemical analysis for pan-Trk in the cytodiagnosis of secretory carcinoma of the salivary gland.

Secretory carcinoma (SC) of the salivary gland is a rare distinct clinicopathological entity characterized by the presence of the ETV6-NTRK3 fusion. Although the characteristic cytological features of SC have been recognized, its cytodiagnosis, especially differentiating SC from acinic cell carcinoma, is challenging. Recent studies have revealed that immunohistochemistry for pan-tyrosine receptor kinase (Trk) and nuclear receptor subfamily 4 group member 3 (NR4A3) are specific for SC and acinic cell carcinoma, respectively. However, the usefulness of immunocytochemical detection of these markers in the diagnosis of SC has not been addressed. Hence, the present study aimed to analyze the usefulness of immunocytochemical staining for pan-Trk and NR4A3 in the cytodiagnosis of SC. We enrolled eight patients with a histopathological diagnosis of SC who underwent preoperative fine-needle aspiration cytological examination. The cytological characteristics were reviewed and immunocytochemical staining for pan-Trk and NR4A3 was performed. The characteristic cytological features noted in the patient cohort included neoplastic cell clusters with a sheet-like and papillary cluster arrangement as well as single cells. Additionally, neoplastic cells with mild to moderately enlarged nuclei and small nucleoli, multi-vacuolated cytoplasm, and intracytoplasmic mucin were also observed. The immunocytochemical analyses clearly demonstrated that all eight specimens showed positive nuclear staining for pan-Trk, but were negative for NR4A3 expression. Although all cases of SC do not always show positive immunoreactivity for pan-Trk, immunocytochemical analysis for pan-Trk may be useful for the cytodiagnosis of SC along with assessment of the characteristic cytological features.

Review of the cytological features of olfactory neuroblastoma: A retrospective single-center study.

Olfactory neuroblastoma (ONB) is a rare malignant neuroectodermal tumor. Due to the rarity, there are scarce reports describing the cytological features of ONB. Thus, we aimed to analyze these cytological features and discuss their differences depending on the histological grading of ONB. Patients with a histopathological diagnosis of ONB who underwent fine-needle aspiration cytology were enrolled in the study. The cytological features, including arrangement and shape of neoplastic cells, nuclear features, and presence of rosettes, were analyzed. Eight patients with ONB were enrolled; cytological specimens of seven patients were obtained from metastatic lesions and that of one patient were obtained from the nasal cavity tumor. The cytological specimens demonstrated variable-sized clusters of neoplastic cells and single cells. Two-cell pattern, composed of large-sized viable neoplastic cells and small-sized apoptotic cells, was noted in 3 of 4 high-grade ONBs but in none of 4 low-grade ONBs. This reflects that the presence of the two-cell pattern may represent higher proliferation in neoplastic cells. The neoplastic cells had scant cytoplasm and round to oval nuclei containing fine to granular chromatin without conspicuous nucleoli. Rosettes and paranuclear blue bodies were observed in one patient. Most cytological specimens of ONB were obtained from metastatic lesions, especially from the cervical lymph node. Thus, ONB should be differentiated from malignant lymphoma and small cell neuroendocrine carcinoma. Recognition of these cytological features of ONB while considering patient history can aid in correctly diagnosing ONBs. Moreover, the presence of two-cell pattern might reflect high-grade histology of ONB.

Longitudinal course of influenza C virus antibody titers of healthy adults in Sendai, Japan.

BACKGROUND: Influenza C virus causes mild respiratory diseases in humans. Previous studies suggested that the predominant hemagglutinin-esterase gene lineage circulating in children might be selected among the adult population, yet the prevalence of influenza C virus in adults has not been described. OBJECTIVES: To evaluate the frequency of influenza C virus infection in adults. STUDY DESIGN: We performed hemagglutination inhibition assays of serum samples collected at periodic occupational medical checkups from employees of a hospital. A total of 679 serum samples were collected from 57 subjects who participated in biannual medical checkups between 2011 and 2016 as part of a longitudinal series. Titers of antibodies against the C/Kanagawa and C/Sao Paulo lineage viruses were detected. RESULTS: Ten serum sample pairs from among the 57 subjects showed at least a four-fold increase in influenza C antibody titers. Samples from three subjects exhibited antibody titer increases for both the C/Kanagawa and C/Sao Paulo lineages, four subjects showed an increased titer against the C/Sao Paulo lineage, and three subjects showed an increased titer against the C/Kanagawa lineage. Half of the antibody titer increases for the C/Kanagawa lineage were detected in May 2014, while the increases for the C/Sao Paulo lineage were detected from 2011 to 2016. CONCLUSION: The 5-year influenza C virus infection rate was estimated at 17.5 %. There were antibodies that cross-reacted with the C/Sao Paulo and C/Kanagawa lineages. The results suggest that C/Sao Paulo was the main lineage in the adult population of this area, with cocirculation of the C/Kanagawa lineage.

Spontaneous infarction of pleomorphic adenoma of the parotid gland: A case report.

Infarction after the fine-needle aspiration (FNA) procedure is a well-recognized phenomenon of salivary gland lesions. Though extremely rare, spontaneous infarction without previous FNA can occur in pleomorphic adenoma (PA). The present report describes a fourth cytological case of spontaneous infarction of PA of the parotid gland using immunocytochemical analysis, to the best of our knowledge, for the first time. A 57-year-old Japanese female presented with persistent swelling of the right neck region. Physical examination revealed a tumour in the right parotid gland, and FNA examination of the tumour was performed following surgical resection. The Papanicolaou smear demonstrated the presence of fully necrotic cell clusters of varying sizes in a necrotic background. Only a few viable cell clusters were observed. These cells were polygonal to spindle-shaped, and exhibited large round to oval nuclei with a conspicuous nucleoli. Although nuclear pleomorphism was noted, the nuclear chromatin was fine. No neoplastic myoepithelial cells were observed. Therefore, it was suspected that these cells were malignant. Immunocytochemical analysis indicated that these atypical cells were positive for p40. Histopathological examination of the resected parotid gland tumour revealed infarcted PA. Our study revealed that the presence of atypical squamous metaplastic cells in a necrotic background was a characteristic cytological feature of infarcted PA, and that these atypical squamous cells can have large nuclei with conspicuous nucleoli and exhibit pleomorphism. Although cytological diagnosis of infarcted PA is difficult, pathologists and cytopathologists must consider the presence of atypical metaplastic squamous cells in benign salivary gland tumours, including infarcted PA.

Low response in eliciting neuraminidase inhibition activity of sera among recipients of a split, monovalent pandemic influenza vaccine during the 2009 pandemic.

Antibodies against influenza virus neuraminidase (NA) protein prevent releasing of the virus from host cells and spreading of infection foci and are considered the 'second line of defence' against influenza. Haemagglutinin inhibition antibody-low responders (HI-LRs) are present among influenza split vaccine recipients. The NA inhibition (NAI) antibody response in vaccinees is worth exploring, especially those in the HI-LRs population. We collected pre- and post-vaccination sera from 61 recipients of an inactivated, monovalent, split vaccine against A/H1N1pdm09 and acute and convalescent sera from 49 unvaccinated patients naturally infected with the A/H1N1pdm09 virus during the 2009 influenza pandemic. All samples were subjected to haemagglutinin inhibition (HI), NAI and neutralisation assays. Most paired sera from naturally infected patients exhibited marked elevation in the NAI activity, and seroconversion rates (SCR) among HI-LRs and HI-responders (HI-Rs) were 60% and 87%, respectively; however, those from vaccinees displayed low increase in the NAI activity, and the SCR among HI-LRs and HI-Rs were 0% and 12%, respectively. In both HI-LRs and HI-Rs, vaccination with the inactivated, monovalent, split vaccine failed to elicit the NAI activity efficiently in the sera of the naive population, compared with the natural infection. Hence, the improvement of influenza vaccines is warranted to elicit not only HI but also NAI antibodies.

Prominent oncocytic metaplasia in pleomorphic adenoma: A potential diagnostic pitfall.

Pleomorphic adenoma (PA) is the most common salivary gland tumor. The cytological features of PA are well recognized, and its diagnosis is straightforward in most cases. Some metaplastic changes in PA are well known; however, occurrence of oncocytic metaplasia in PA is very rare. In this report, we describe the first cytological case of prominent oncocytic metaplasia in PA identified based on immunocytochemical analysis. We report the case of a 62-year-old Japanese female who presented with swelling of the left neck region. A fine-needle aspiration cytologic examination was performed followed by surgical resection. The Papanicolaou smear revealed the presence of discohesive neoplastic cells in a myxoid background. These neoplastic cells had a relatively rich, granular cytoplasm, and round nuclei with moderate pleomorphism. Initial cytodiagnosis revealed carcinoma ex PA (CXPA). Immunocytochemical analysis showed that abundant mitochondria were present in the cytoplasm of these neoplastic cells. Histopathological examination of the resected tumor demonstrated proliferation of oncocytic neoplastic cells within a myxoid material and the presence of conventional PA components. A final diagnosis of prominent oncocytic metaplasia in PA was made. Oncocytic metaplasia showed nuclear atypia and pleomorphism; therefore, CXPA, which presents with severe nuclear atypia and necrotic background, must be differentiated from oncocytic metaplastic PA. Recognition of oncocytic metaplasia in PA is important for correct diagnosis.

The rhizobial autotransporter determines the symbiotic nitrogen fixation activity of Lotus japonicus in a host-specific manner.

Leguminous plants establish endosymbiotic associations with rhizobia and form root nodules in which the rhizobia fix atmospheric nitrogen. The host plant and intracellular rhizobia strictly control this symbiotic nitrogen fixation. We recently reported a Lotus japonicus Fix- mutant, apn1 (aspartic peptidase nodule-induced 1), that impairs symbiotic nitrogen fixation. APN1 encodes a nodule-specific aspartic peptidase involved in the Fix- phenotype in a rhizobial strain-specific manner. This host-strain specificity implies that some molecular interactions between host plant APN1 and rhizobial factors are required, although the biological function of APN1 in nodules and the mechanisms governing the interactions are unknown. To clarify how rhizobial factors are involved in strain-specific nitrogen fixation, we explored transposon mutants of Mesorhizobium loti strain TONO, which normally form Fix- nodules on apn1 roots, and identified TONO mutants that formed Fix+ nodules on apn1 The identified causal gene encodes an autotransporter, part of a protein secretion system of Gram-negative bacteria. Expression of the autotransporter gene in M. loti strain MAFF3030399, which normally forms Fix+ nodules on apn1 roots, resulted in Fix- nodules. The autotransporter of TONO functions to secrete a part of its own protein (a passenger domain) into extracellular spaces, and the recombinant APN1 protein cleaved the passenger protein in vitro. The M. loti autotransporter showed the activity to induce the genes involved in nodule senescence in a dose-dependent manner. Therefore, we conclude that the nodule-specific aspartic peptidase, APN1, suppresses negative effects of the rhizobial autotransporter in order to maintain effective symbiotic nitrogen fixation in root nodules.

Fluctuations in Antibody Titers against Enterovirus D68 in Pediatric Sera Collected in a Community before, during, and after a Possible Outbreak.

We previously reported a hospital-based epidemiological study on enterovirus (EV)-D68 infection among children during the autumn of 2015, which indirectly inferred an outbreak in Sendai, Japan. In this study, stocked sera of children (aged 0-6 years; without symptoms of infectious diseases) in the Sendai community collected during 4 periods (1 year before, 6 months before, immediately after, and 1 year after the possible outbreak period) were analyzed using the neutralization antibody titer assay to determine community children's immunity levels against EV-D68 infection. The immunity levels were confirmed to have increased during the possible outbreak period and to have gradually waned over 1 year without another outbreak. These results provide background information supporting the results of our previous hospital-based surveillance study.

Neuroendocrine carcinoma diagnosis from bile duct cytological specimens: A retrospective single-center study.

Neuroendocrine carcinoma (NEC) in the extrahepatic bile duct is extremely rare and clinically aggressive. Cytological examination of bile and/or bile duct brushing specimens plays an important role in the diagnosis of carcinoma of the extrahepatic bile duct, but only a few articles have described the cytological features of NEC in this area. Thus, we retrospectively analyzed the cytological features of NEC in bile and/or bile duct brushing specimens. Patients with a histopathological diagnosis of NEC who underwent bile and/or bile duct brush cytological examination were enrolled in this study. The cytological features, including the background, arrangement, and shape of the neoplastic cells, and nuclear and cytoplasmic features were reviewed. Six patients with small cell NEC were enrolled, and two of them had pancreatic tumors directly invading the bile duct wall. The cytological specimens showed small and/or large neoplastic cell clusters with occasional single cells in all cases. The neoplastic cells had a high nuclear/cytoplasmic ratio and round-to-oval nuclei with powdery chromatin, inconspicuous nucleoli, and scant cytoplasm. Nuclear molding was a characteristic finding in all cases. One case had an adenocarcinoma component, which was also present in the cytological specimen. Cytological examination of bile and/or bile duct brushing specimens can be useful for the diagnosis of small cell NEC. This is an extremely rare but aggressive carcinoma, and its diagnosis by identifying characteristic cytological features may facilitate early detection and treatment.

Metastatic salivary duct carcinoma in cardiac and pleural effusions: A case report with immunocytochemical analysis for androgen receptor and HER2.

Salivary duct carcinoma (SDC) is a relatively rare highly aggressive salivary gland tumor. Although SDC shows frequent lymph node and distant metastases, the presence of neoplastic cells in the pleural effusion is extremely rare. In this report, we describe the first documented cytological case of metastatic SDC in cardiac and pleural effusions with immunocytochemical analyses for androgen receptor (AR) and human epidermal growth factor receptor (HER)2. A 52-year-old Japanese male developed cardiac tamponade and respiratory discomfort after surgery and chemo-radiation therapy for SDC of the right submandibular gland. Aspiration of the cardiac and pleural effusions was performed. The Papanicolaou-stained cytological specimens of cardiac and pleural effusions showed that numerous small ball-like or papillary structures were present in an inflammatory background. The neoplastic cells had rich granular cytoplasm and large round to oval nuclei containing conspicuous nucleoli. Immunocytochemical analyses clearly demonstrated positivity for AR and strong membranous expression of HER2 in the neoplastic cells. Accordingly, a cytodiagnosis of metastatic SDC was made. Recently, HER2-targeted or AR deprivation therapy have been introduced for patients with SDC, therefore, determination of expression profiles of AR and HER2 may be crucial for developing a treatment strategy for patients with metastatic SDC. According to the results of the present report, immunocytochemical analyses for AR and HER2 in the effusion specimens may be useful for determination of a treatment strategy for patients with metastatic SDC.

Antipsychotic drugs scavenge radiation-induced hydroxyl radicals and intracellular ROS formation, and protect apoptosis in human lymphoma U937 cells.

Antioxidant activity has been reported for some atypical antipsychotic drugs; however, the detailed mechanism is not well known. Here, we investigated the effects of atypical antipsychotic drugs on •OH radical formation, intracellular reactive oxygen species (ROS), and apoptosis induced by ionising radiation. The reaction rate constants with •OH radicals were determined for five antipsychotic drugs as follows, in descending order: olanzapine, aripiprazole, clozapine, haloperidol, and risperidone. Experiments with aminophenyl fluorescein, a fluorescent dye, showed that olanzapine and clozapine could scavenge intracellular ROS. However, experiments with hydroxyphenyl fluorescein showed that only olanzapine inhibited ROS generation. X-irradiation-induced apoptosis in human lymphoma U937 cells was inhibited by clozapine at relatively low concentrations and by olanzapine at higher concentrations. Clozapine inhibited caspase-8 and caspase-3 activation and prevented loss of mitochondrial membrane potential. In contrast, olanzapine inhibited X-irradiation-induced p-JNK activation. Although the atypical antipsychotic drugs used here have relatively high reaction rate constants with •OH radicals in aqueous solutions, inhibition of intracellular ROS was not due to •OH radical scavenging. In addition, suppression of X-irradiation-induced apoptosis was not directly linked with intracellular ROS scavenging. When apoptosis signalling pathways were studied, clozapine-mediated inhibition of apoptosis was dependent on caspase-3 and caspase-8. In contrast, olanzapine inhibited apoptosis via down regulation of X-irradiation-induced p-JNK. These results suggested that both olanzapine and clozapine have antioxidative and antiapoptotic activities via distinct pathways, and provide useful information for better understanding of drug characteristics.

Imprint cytology of strumal carcinoid of the ovary: A case report with immunocytochemical analysis.

Strumal carcinoid is a rare ovarian tumor defined as carcinoid associated with struma ovarii. We report here the second cytological case of strumal carcinoid and performed immunocytochemical analysis for the first time. A 68-year-old Japanese female was found to have a solid tumor with small cystic components in the left ovary, and bilateral salpingo-oophorectomy was performed. The Papanicolaou smear of the imprint cytological specimen of the left ovarian tumor revealed presence of two distinct components. The first component included thyroid follicles, which was composed of flat sheets of polygonal epithelial cells without nuclear groove and intranuclear inclusion. The other component was composed of trabecular clusters of columnar cells containing round to slender nuclei with "salt and pepper" chromatin. Immunocytochemical analysis revealed that synaptophysin was expressed in the latter component. Therefore, a cytodiagnosis of strumal carcinoid was made. Histopathological analyses confirmed the diagnosis of strumal carcinoid. Albeit rare, carcinoid tumor occurs in the ovary, and the recognition of characteristic nuclear features and cellular arrangement leads to correct cytodiagnosis. Presence of struma ovarii component suggests an ovarian origin. Moreover, immunocytochemical analysis for neuroendocrine markers aids its differential diagnosis from granulosa cell tumor and carcinoma arising from struma ovarii.

Association of Serum HB-EGF Value and Response to Chemotherapy in Patients with Recurrent Ovarian Cancer.

BACKGROUND/AIM: Many anticancer agents including molecularly-targeted drugs have been developed for ovarian cancer. However, the prognosis of recurrent ovarian cancer remains extremely poor. Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is reported as a rational target for ovarian cancer therapy. Moreover, serum HB-EGF expression is recognized as a biomarker in patients with primary ovarian cancer. MATERIALS AND METHODS: We analysed serum samples with recurrent ovarian cancer at the Fukuoka University Hospital from April 2009 to March 2014. To assess the clinical significance of serum HB-EGF in recurrent ovarian cancer, the association between serum HB-EGF levels and prognosis in patients with recurrent ovarian cancer was examined using ELISA. RESULTS: Patients with high serum HB-EGF expression showed a significantly poor response to second-line chemotherapeutic agents compared with patients with low HB-EGF levels. CONCLUSION: HB-EGF expression in serum may be a potential therapeutic indicator for novel HB-EGF-targeted therapy in recurrent ovarian cancer.

Case study-based time-course analysis of symptoms of respiratory syncytial virus infections followed by acute sinusitis in otherwise-healthy adults.

Reports on respiratory syncytial virus (RSV) infections are abundant in pediatric and geriatric populations but not many in healthy adults, and particularly, those which demonstrated the illness throughout its time course are rare. We report two otherwise-healthy adult cases, showing a number of evidence essential for confirmation of exclusive infections with RSV, and document their clinical features from the onset of the disease to recovery, including secondary sinusitis with magnetic resonance (MR) and computed tomography (CT) images. The infection was proven by isolating RSV belonging to subgroup B and by observing elevated anti-RSV antibody titer in the paired sera. Possible contribution of other pathogens including almost all respiratory viruses and representative bacteria, was excluded by negative results in multiplex PCR examination. In the first case, illness initiated with pharyngeal pain, followed by symptoms of sneezing, severe rhinorrhea and coughing, which peaked at approximately 5-7 days and persisted for 12 days. The patient experienced a slight chill, but the body temperature did not exceed 37 °C during illness. The patient showed no significant finding but only a slight increase in serum C-reactive protein level in the routine clinical laboratory examinations. On the 9th day of illness, a dull headache started persisting for at least a week after which it gradually waned. Sinusitis was found by chance on MR images of maxillary sinus 8 days after the headache started, and the finding disappeared on CT images taken after 6 months. In the second case, the symptoms included severe rhinorrhea and dull facial pain around the upper nose; the pain also occurred on the 9th day of illness and the symptom was clinically diagnosed to be acute sinusitis during a visit to a physician.

Loss-of-function of ASPARTIC PEPTIDASE NODULE-INDUCED 1 (APN1) in Lotus japonicus restricts efficient nitrogen-fixing symbiosis with specific Mesorhizobium loti strains.

The nitrogen-fixing symbiosis of legumes and Rhizobium bacteria is established by complex interactions between the two symbiotic partners. Legume Fix- mutants form apparently normal nodules with endosymbiotic rhizobia but fail to induce rhizobial nitrogen fixation. These mutants are useful for identifying the legume genes involved in the interactions essential for symbiotic nitrogen fixation. We describe here a Fix- mutant of Lotus japonicus, apn1, which showed a very specific symbiotic phenotype. It formed ineffective nodules when inoculated with the Mesorhizobium loti strain TONO. In these nodules, infected cells disintegrated and successively became necrotic, indicating premature senescence typical of Fix- mutants. However, it formed effective nodules when inoculated with the M. loti strain MAFF303099. Among nine different M. loti strains tested, four formed ineffective nodules and five formed effective nodules on apn1 roots. The identified causal gene, ASPARTIC PEPTIDASE NODULE-INDUCED 1 (LjAPN1), encodes a nepenthesin-type aspartic peptidase. The well characterized Arabidopsis aspartic peptidase CDR1 could complement the strain-specific Fix- phenotype of apn1. LjAPN1 is a typical late nodulin; its gene expression was exclusively induced during nodule development. LjAPN1 was most abundantly expressed in the infected cells in the nodules. Our findings indicate that LjAPN1 is required for the development and persistence of functional (nitrogen-fixing) symbiosis in a rhizobial strain-dependent manner, and thus determines compatibility between M. loti and L. japonicus at the level of nitrogen fixation.

Opioid receptor activation is involved in neuroprotection induced by TRPV1 channel activation against excitotoxicity in the rat retina.

Recently, we reported that capsaicin, a transient receptor potential vanilloid type1 (TRPV1) agonist, protected against excitotoxicity induced by intravitreal N-methyl-D-aspartic acid (NMDA) in the rats in vivo. It has been reported that morphine, an opioid receptor agonist, ameliorated excitotoxicity induced by ischemia-reperfusion in the retina, and that capsaicin-induced neuroprotection was reduced by naloxone, an opioid receptor antagonist in the brain. The aim of the present study is to clarify whether activation of opioid receptors is involved in the capsaicin-induced neuroprotection in the retina. Under ketamine/xylazine anesthesia, male Sprague-Dawley rats were subjected to intravitreal NMDA injection (200nmol/eye). Capsaicin (5.0nmol/eye), calcitonin gene-related peptide (CGRP; 0.05pmol/eye), ß-endorphin (0.5 pmol/eye), substance P (5nmol/eye), and naloxone (0.5nmol/eye) were intravitreally administered simultaneously with NMDA. Morphometric evaluation 7 days after NMDA injection showed that intravitreal NMDA injection resulted in ganglion cell loss. Capsaicin, CGRP, ß-endorphin, and substance P prevented this damage. Treatment with naloxone (0.5nmol/eye) almost completely negated the protective effects of capsaicin, CGRP, ß-endorphin, and substance P in the NMDA-injected rats. These results suggested that activation of opioid receptors is possibly involved in the protective effect of capsaicin.

Lymphoepithelioma-like hepatocellular carcinoma: a case report with emphasis on the cytological features.

Lymphoepithelioma-like hepatocellular carcinoma (LEL-HCC) is a rare distinct histopathological subtype of HCC, which is characterized histopathologically by the presence of abundant lymphocytes around the neoplastic cells, and less than 50 cases have been reported. In this report, we describe the first cytological case of LEL-HCC. A 58-year-old Japanese male had an elevated serum alpha-fetoprotein (AFP) level, and computed tomography scan demonstrated a tumorous lesion with contrast enhancement in the liver, thus, surgical resection was performed. The Papanicolaou smear of the liver tumor demonstrated small clusters and trabeculae of large-sized polygonal cells in a background of an abundance of small lymphocytes. These tumor cells had a rich granular cytoplasm and large centrally located round to oval nuclei containing conspicuous nucleoli. Immunocytochemical analyses revealed that these cells were positive for AFP, glypican-3, and Hep-Par1. Histopathological study demonstrated LEL-HCC. The cytological features of the present case represent both lymphoepithelioma-like carcinoma and conventional HCC. The prognosis of LEL-HCC may be favorable. Therefore, the diagnosis of this type of tumor is important, and a cytological examination can provide useful information for diagnosis of LEL-HCC.

Growth Rate of and Gene Expression in Bradyrhizobium diazoefficiens USDA110 due to a Mutation in blr7984, a TetR Family Transcriptional Regulator Gene.

Previous transcriptome analyses have suggested that a gene cluster including a transcriptional regulator (blr7984) of the tetracycline repressor family was markedly down-regulated in symbiosis. Since blr7984 is annotated to be the transcriptional repressor, we hypothesized that it is involved in the repression of genes in the genomic cluster including blr7984 in symbiotic bacteroids. In order to examine the function and involvement of the blr7984 gene in differentiation into bacteroids, we compared the free-living growth/symbiotic phenotype and gene expression between a blr7984-knockout mutant and the wild-type strain of Bradyrhizobium diazoefficiens USDA110. The mutant transiently increased the cell growth rate under free-living conditions and nodule numbers over those with the wild-type strain USDA110. The expression of three genes adjacent to the disrupted blr7984 gene was strongly up-regulated in the mutant in free-living and symbiotic cells. The mutant also induced the expression of genes for glutathione S-transferase, cytochrome c oxidases, ABC transporters, PTS sugar transport systems, and flagella synthesis under free-living conditions. bll7983 encoding glutathione S-transferase was up-regulated the most by the blr7984 disruption. Since redox regulation by glutathione is known to be involved in cell division in prokaryotes and eukaryotes, the strong expression of glutathione S-transferase encoded by the bll7983 gene may have caused redox changes in mutant cells, which resulted in higher rates of cell division.