PubMed Health⌕ Search

Biomedical subjects

Toshihiko Ishida

Publications and source records attributed to Toshihiko Ishida.

At least 37 records · Page 2Linked to original sources

[A case of pulmonary actinomycosis, who expectorated sulfur granules, caused by Actinomyces odontolyticus and Actinomyces meyeri].

A 51-year-old man complaining of cough and bloody sputum, was admitted to our hospital because of antibiotic-resistant chronic pneumonia in the right upper lobe. Initially, bronchoscopic examination and sputum culture revealed no evidence of malignancy or any specific infection, either pathologically or microbiologically. However, pathological examination of a solid body expectorated with sputum revealed typical sulfur granules, indicating pulmonary actinomycosis. Two actinomyceses named Actinomyces odontolyticus and Actinomyces meyeri were detected later. Pulmonary infection caused by these types of actinomyceses is rare, and the diagnostic procedure seemed to be unusual.

Actinomycosis↗

Insulin-like growth factor-i regulation of hepatic scavenger receptor class BI.

High-density lipoprotein mediates a normal physiological process called reverse cholesterol transport. This process enables the transfer of cholesterol from peripheral tissues to the liver for further metabolism and eventual secretion in the form of bile. The scavenger receptor of the B class (SR-BI), human homolog of SR-BI, and CD36 and LIMPII analogous-1 (CLA-1) are different names for the same receptor that facilitates hepatocellular uptake of cholesterol from high-density lipoprotein. The pivotal role of this receptor in enterohepatic circulation of cholesterol and bile salts underlies our interest to study the regulation of hepatic SR-BI gene in response to the actions of IGF-I. The results of our studies showed that endogenous expression of SR-BI/CLA-1 was suppressed by exposure to GH or IGF-I in cultured HepG2 cells. This observation extended to a whole animal model of rats continuously infused with IGF-I. IGF-I decreased transcriptional activity of the SR-BI promoter. However, the inhibitory effect of IGF-I on SR-BI/CLA-1 promoter activity was abrogated by wortmannin, a specific inhibitor of phosphoinositide 3-kinase (PI3-K). Exposure of HepG2 cells to IGF-I elicited a rapid phosphorylation of Akt. We also demonstrated that the constitutively active form of both p110, a subunit of PI3-K, and Akt inhibited activity of the human SR-BI/CLA-1 promoter. Furthermore, the dominant-negative mutant of Akt abolished the ability of IGF-I to suppress activity of the SR-BI/CLA-1 promoter. In conclusion, PI3-K/Akt pathways participate in IGF-I-suppression of SR-BI/CLA-1 expression, which suggests that the activation of Akt plays an important role in cholesterol metabolism in liver.

Acromegaly↗

Thyrotropin-releasing hormone-stimulated thyrotropin expression involves islet-brain-1/c-Jun N-terminal kinase interacting protein-1.

Islet-brain-1 (IB1)/c-Jun N-terminal kinase interacting protein 1 (JIP-1) is a scaffold protein that is expressed at high levels in neurons and the endocrine pancreas. IB1/JIP-1 interacts with the c-Jun N-terminal kinase and mediates the specific physiological stimuli (such as cytokines). However, the potential role of the protein in the pituitary has not been evaluated. Herein, we examined expression of the gene encoding IB1/JIP-1 and its translated product in the anterior pituitary gland and a pituitary cell line, GH3. We then examined the potential role of IB1/JIP-1 in controlling TSH-beta gene expression. Exposure of GH3 cells to TRH stimulated the expression of IB1/JIP-1 protein levels, mRNA, and transcription of the promoter. The increase of IB1/JIP-1 content by transient transfection study of a vector encoding IB1/JIP-1 or by the stimulation of TRH stimulates TSH-beta promoter activity. This effect is not found in the presence of a mutated nonfunctional (IB1S59N) IB1/JIP-1 protein. Together, these facts point to a central role of the IB1/JIP-1 protein in the control of TRH-mediated TSH-beta stimulation.

Adaptor Proteins, Signal Transducing↗

Role of calcium-calmodulin-dependent protein kinase cascade in thyrotropin (TSH)-releasing hormone induction of TSH and prolactin gene expression.

TRH binds to a membrane receptor that activates several intracellular signaling pathways and increases transcription of the TSH and prolactin (PRL) genes. Although TRH induces TSH and PRL gene expression, the underlying mechanism is not clear. In this report we examined the role of the Ca(2+)/calmodulin-dependent protein (CaM) kinase cascade in mediating TRH-stimulated transcription of TSH and PRL. RT-PCR and Western blot analysis were used to show that CaM kinase kinase (CaM-KK) and CaM IV (CaM-KIV) were present in rat anterior pituitary and its cell line GH(3). Next, the effects of constitutively active CaM-KIV (CaM-KIVc) or its dominant negative mutant (CaM-KIVdn) on TSH and PRL promoter activity were tested in GH(3) cells. The results showed that either CaM-KIVc alone or an upstream kinase, CaM-KK, induced the activity of both TSH and PRL promoters. Exposure of GH(3) cells to 100 microm TRH induced CaM-KIV activity within 5 min and, as expected, also increased both TSH and PRL promoter activity. In contrast, cells carrying the CaM-KIVdn isoform had suppressed TRH induction of both TSH and PRL promoter activity. These results indicate that the CaM-KK-CaM-KIV cascade probably plays an important role in TRH induction of TSH and PRL transcriptional activity in pituitary cells.

Animals↗

A mutant high-density lipoprotein receptor inhibits proliferation of human breast cancer cells.

High-density lipoprotein (HDL) stimulates the growth of many types of cells, including those of breast cancer. High levels of HDL are associated with an increased risk of breast cancer development. A scavenger receptor of the B class (SR-BI)/human homolog of SR-BI, CD36, and LIMPII analogous-1 (CLA-1) facilitates the cellular uptake of cholesterol from HDL and thus augments cell growth. Furthermore, HDL is also believed to have antiapoptotic effects on various cell types, and this feature adds to its ability to promote cell growth. These collaborative roles of HDL and CLA-1 prompted us to assess the function of these components on human breast cancer cells. In this study, we created a mutant CLA-1 (mCLA) that lacked the COOH-terminal tail to determine its potential role in breast cancer cell growth. Expression of mCLA inhibited the proliferation of breast cancer cell line MCF-7. This inhibitory action of mCLA required the transcriptional factor activator protein-1 (AP-1), and the mutant receptor also affected the antiapoptotic features of HDL. The effect of HDL on AP-1 activation and [(3)H]thymidine incorporation was abrogated by wortmannin, a specific inhibitor of phosphoinositide 3-kinase. Furthermore, the dominant negative mutant of Akt abolished the ability of HDL to activate AP-1. These findings raise the possibility that the inhibitors of the effects of HDL may be of therapeutic value for breast cancer.

Apoptosis↗

Effect of carbonic anhydrase-related protein VIII expression on lung adenocarcinoma cell growth.

Carbonic anhydrase-related protein VIII (CA-RP VIII) is expressed in most non-small cell lung cancer, and especially strongly at the front of tumor progression. Screening analysis of CA-RP VIII expression in a panel of cultured lung cancer cell lines showed that a well differentiated adenocarcinoma cell line, PC-9, appeared to lack CA-RP VIII. Subsequently, CA8 cDNA was transfected with an expression vector into PC-9. Ectopic overexpression of CA-RP VIII reduced the growth of PC-9 cells on uncoated culture dishes, especially when the cultures were started at low cell density, but increased cell growth on laminin-coated dishes. Interestingly, ectopic CA-RP VIII expression markedly reduced caspase-3 activity induced by serum starvation and anti-cancer agents in PC-9 cells. The present findings suggest that CA-RP VIII expression promotes progression of lung cancer by multifarious mechanisms.

Adenocarcinoma↗

Clinical features of eleven cases of Mycobacterium avium-intracellulare complex pulmonary disease associated with pneumoconiosis.

The relationship between silicosis and tuberculosis is well known. Also other mycobacteria such as Mycobacterium kansasii often occur in association with pneumoconiosis. However, there are few reports describing an association of M. avium-intracellulare complex (MAC) lung disease and pneumoconiosis. The purpose of the present study is to describe clinical features of MAC respiratory infection associated with pneumoconiosis. Eleven patients with MAC respiratory infection associated with pneumoconiosis (all men, 6 with silicosis and 5 with welders' pneumoconiosis) were collected. A determination of whether or not MAC caused pulmonary disease was made using the 1997 criteria required by the American Thoracic Society. Radiologically, cavity formation as well as upper lung field predominance of MAC disease were observed in 8 of 11 cases (72.7%). Two of 11 patients died of respiratory failure. Our present study clearly demonstrates that clinical features of MAC respiratory infection associated with pneumoconiosis were different from MAC without underlying diseases.

Aged↗

Diffuse large B-cell lymphoma presenting with hypercalcemia and multiple osteolysis.

Osteolysis and hypercalcemia are observed in 5-15%, and 10%, respectively, of malignant lymphoma patients during their clinical course. However, both osteolysis and hypercalcemia are uncommon at onset of the disease. We encountered a 24-year-old male non-Hodgkin's lymphoma patient who had multiple osteolytic lesion from the onset of the disease and repeated episodes of hypercalcemia during the clinical course. The patient died with refractory disease. We studied the expression of chemokines which might affect bone resorption using the reverse transcriptase-polymerase chain reaction (RT-PCR) method. Increased expressions of MIP-1alpha, MIP-1beta and RANKL, which are osteoclast-activating factors, were observed in the RNA derived from the patient's lymphoma cells. The secretion of osteoclast-activating factors such as MIP-1alpha by the tumor cells (and/or bone marrow stromal cells) might be involved in the etiology of osteolysis and hypercalcemia in some malignant lymphoma cases.

Acid Phosphatase↗

Pyothorax caused by Nocardia otitidiscaviarum in a patient with rheumatoid vasculitis.

We report a case of pyothorax caused by Nocardia (N.) otitidiscaviarum infection in a 69-year-old man with rheumatoid vasculitis, who was regularly treated with prednisolone in our hospital. Initially, the patient responded poorly to intravenous imipenem/cilastatin (IPM/CS), minocyclin (MINO), and oral trimethoprim-sulfamethoxazole (TMP-SMX), but later improved after treatment with levofloxacin (LVFX) and gentamicin sulfate (GM) according to in vitro susceptibility tests. To our knowledge, this is the first description of pyothorax caused by N. otitidiscaviarum infection. It is a rare disease, but recognition of the disease in immunocompromised patients and the prompt initiation of appropriate treatments based on isolation of the pathogen and susceptibility testing can lead to a successful outcome.

Adrenal Cortex Hormones↗

Three cases of non-specific interstitial pneumonia associated with primary lung cancer.

NSIP associated with primary lung cancer has been rarely reported. In the present report, three cases of histologically proven non-specific interstitial pneumonia (NSIP) associated with primary lung cancer are described. Importantly, in our 3 cases, interstitial pneumonia which is histologically proven to be NSIP was observed diffusely in both lungs. NSIP in these 3 cases responded to steroid therapy. However, 2 patients died from primary lung cancer and 1 patient died from progression of the interstitial pneumonia. Although the association between lung cancer and NSIP has been rarely documented, this combination was considered to be one of the paraneoplastic phenomena. The possible association between primary lung cancer and NSIP is discussed.

Adenocarcinoma↗

The role of calcium/calmodulin-dependent protein kinase cascade in glucose upregulation of insulin gene expression.

A number of factors have been reported to affect insulin synthesis in beta-cells. Although glucose is the most important regulator of insulin gene expression in pancreatic beta-cells, the mechanisms whereby glucose stimulates insulin gene transcription in response to changes in glucose concentration have not been clarified yet. In this study, we examined the role of the Ca(2+)/calmodulin (CaM)-dependent protein kinase (CaM-K) cascade in transcriptional activation of insulin. RT-PCR, Western blotting, and immunohistochemical staining analysis revealed that CaM-K kinase-alpha (CaM-KKalpha) and CaM-KIV were localized in rat pancreatic beta-cells and their cell line, INS-1. Exposure of INS-1 cells to 11.2 mmol/l glucose elicited an increase of insulin promoter activity as well as upregulation of CaM-KIV activity within 2 min after stimulation. We investigated the influence on insulin promoter activity of the constitutively active form (CaM-KIVc) or dominant-negative mutant (CaM-KIVdn) of CaM-KIV in transfected INS-1 cells. CaM-KIVc alone was sufficient, and the upstream kinase, CaM-KK, was enhanced to upregulate the insulin promoter activity in INS-1 cells. Furthermore, cotransfection of CaM-KIVdn suppressed to a significant degree the glucose-upregulated activity of the insulin promoter. Taken together, these results indicated that the CaM-KK/CaM-KIV cascade might play an important role in glucose-upregulated transcriptional activation of the insulin gene.

Animals↗

Correlation of Skp2 with carcinogenesis, invasion, metastasis, and prognosis in colorectal tumors.

In colorectal tumors, S-phase kinase-associated protein 2 (Skp2) still has numerous important questions unanswered: its expression in adenomas, its correlation with key clinicopathological indices, its association with patient prognosis, its variation in lymph node metastases, and its association with many cell-cycle regulators. To answer these questions in colorectal tumors, Skp2, cyclin A, cyclin B1, cyclin E, CDK2, and Ki67 were immunohistochemically stained in 12 normal mucosa, 36 adenomas, 11 carcinomas in adenomas, 102 primary carcinomas, and 12 paired lymph node metastases; and Skp2 was examined by Western blot in 8 pairs of normal mucosa and carcinomas. Situated in nuclei, Skp2 expression significantly increased from normal mucosa through adenoma to primary carcinoma (p<0.0001), from mild through moderate to severe dysplasia in adenomas (p=0.038), from peripheral adenoma to paired central carcinoma (p=0.0033), and from primary carcinoma to lymph node metastasis (p=0.015), and these increases were confirmed by Western blot. Expression, however, relatively declined significantly in the primary carcinomas showing deep invasion (p=0.0113), lymph nodal metastases (p=0.0268), and poor prognosis for all (p=0.0104) or stage III patients (p=0.0119). High Skp2 was also significantly linked with elevated cyclin A, cyclin B1, cyclin E, CDK2 (in primary carcinomas only), and Ki67 in both adenomas and primary carcinomas. Thus, overexpression of Skp2 is associated with colorectal carcinogenesis and late metastasis to lymph nodes, whereas relative reduction of Skp2 is correlated with local invasion of primary carcinoma.

Aged↗

[Fructosamine].

Explore the source record for details and available documents.

Fructosamine↗

Expression of human scavenger receptor B1 on and in human platelets.

OBJECTIVE: The abundance of HDL particles correlates inversely with the incidence of coronary heart disease. The human scavenger receptor B1 (hSR-B1/CLA-1) is a receptor for HDL. Expression of hSR-B1/CLA-1 mRNA and protein in human platelets was determined using reverse transcriptase-polymerase chain reaction and Western blot, respectively. Presence of the protein on the surface of platelets was shown using flow cytometry. METHODS AND RESULTS: Immunochemical staining for hSR-B1/CLA-1 showed that it was expressed in megakaryocytes, the platelet precursors of human bone marrow. These findings prompted us to ask whether hSR-B1/CLA-1 was differentially expressed on platelets obtained from patients with atherosclerotic disease compared with those in control subjects. Our findings showed that abundance of hSR-B1/CLA-1 was significantly reduced on the surface of platelets from patients with atherosclerotic disease. The reduced levels of hSR-B1/CLA-1 were associated with increased cholesterol ester content in platelets from patients with atherosclerotic disease compared with control subjects. A negative correlation existed between hSR-B1/CLA-1 expression and platelet aggregation. In summary, our studies show that the HDL receptor hSR-B1/CLA-1 is expressed in platelets and their precursor, the megakaryocyte. The levels of hSR-B1/CLA-1 expression correlate inversely with cholesterol ester content and platelet aggregation. CONCLUSIONS: These findings suggest that determining the level of hSR-B1/CLA-1 expression on the platelets may be a useful clinical marker for atherosclerotic diseases.

Adult↗

A case of lung cancer associated with pneumoconiosis diagnosed by fluorine-18 fluorodeoxyglucose positron emission tomography.

We report a case of lung cancer arising from progressive massive fibrosis (PMF) associated with pneumoconiosis. In this case, fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) was able to clearly distinguish the lung cancer from PMF, suggesting a potential usefulness of FDG-PET in cancer screening in patients with pneumoconiosis. To our knowledge, this is the first description of an FDG-PET image of lung cancer arising from PMF.

Fluorodeoxyglucose F18↗