Biomedical subjects

K Asano

Publications and source records attributed to K Asano.

At least 145 records · Page 8Linked to original sources

PubMed1998

Plasma soluble fas and soluble fas ligand in chronic glomerulonephritis.

It has been reported that glomerular cells with apoptosis and positive Fas immunoreactivity are seen in proliferative glomerulonephritis (PGN). Fas induces apoptosis when it binds to Fas ligand (Fas-L) or soluble Fas-L (sFas-L). However, soluble Fas (sFas) blocks apoptosis by inhibiting binding between Fas and Fas-L or sFas-L. That is, Fas, Fas-L, and sFas-L are inducers of apoptosis, but sFas is an inhibitor of apoptosis. We studied the relationship between the plasma levels of sFas and sFas-L in 32 patients with various types of adult chronic glomerulonephritis. Patients with serum creatinine levels >1.5 mg/dl (132.6 micromol/l) were excluded. The plasma levels of sFas-L were within the normal limits in all patients. The plasma levels of sFas in the patients with minimal-change (n = 8) and membranous nephropathy (n = 7) were similar to the age- and sex-matched controls. However, the plasma sFas levels were significantly elevated in patients with mesangial PGN (n = 10) and membranoproliferative glomerulonephritis (n = 7)(3. 4 +/- 0.9 and 3.9 +/- 1.5 ng/ml, respectively) as compared with the age- and sex-matched controls (controls: 2.1 +/- 0.4 and 2.2 +/- 0.6 ng/ml, respectively). In PGN, according to increase of histological grade and decrease of creatinine clearance, the number of TUNEL-positive cells in glomeruli is decreased in spite of an increase of the Fas positivity, and plasma sFas is increased. The degree of proliferative change is determined by the balance between proliferation and apoptosis and/or necrosis. Therefore, increased plasma sFas in PGN may inhibit apoptosis in glomeruli and may be one of the progressing factors in PGN. Thus, we conclude that an increase in plasma sFas levels is important to the protection of apoptosis in PGN.

Adult↗

PubMed1998

Apoptosis induction of POS canine osteosarcoma cells by vitamin D and retinoids.

Vitamin D3: 1-alpha, 25(OH)2D3 (calcitriol), 22-oxa-1,25(OH)2D3 (OCT), cholecalciferol (vitamin D3), and retinoids: all-trans retinoic acid (ATRA) and 9-cis retinoic acid, induced morphological changes in POS canine osteosarcoma cells into elongated, spindle or fibroblast like-shaped cells, and apoptotic like cell death characterized by cell shrinkage, condensation and margination of the nucleus for all drugs at 10(-6)M-10(-9)M after 72 to 120 hr culture. Apoptosis as shown by DNA laddering was induced at 48 hr by all drugs at 10(-6)M, 10(-7)M at 96 hr, 10(-8)M and 10(-9)M at 120 hr respectively. These vitamins are suggested to adjunct antineoplastic agents in canine osteosarcoma therapy by induction of apoptosis.

Animals↗

PubMed1998

Mechanical strain- and high glucose-induced alterations in mesangial cell collagen metabolism: role of TGF-beta.

Cultured mesangial cells (MC) exposed to cyclic mechanical strain or high glucose levels increase their secretion of transforming growth factor-beta1 (TGF-beta1) and collagen, suggesting possible mechanisms for the development of diabetic renal sclerosis resulting from intraglomerular hypertension and/or hyperglycemia. This study examines whether glucose interacts with mechanical strain to influence collagen metabolism and whether this change is mediated by TGF-beta. Accordingly, rat MC were grown on flexible-bottom plates in 8 or 35 mM glucose media, subjected to 2 to 5 d of cyclic stretching, and assayed for TGF-beta1 mRNA, TGF-beta1 secretion, and the incorporation of 14C-proline into free or protein-associated hydroxyproline to assess the dynamics of collagen metabolism. Stretching or high glucose exposure increased TGF-beta1 secretion twofold and TGF-beta1 mRNA levels by 30 and 45%, respectively. However, the combination of these stimuli increased secretion greater than fivefold without further elevating mRNA. In 8 mM glucose medium, stretching significantly increased MC collagen synthesis and breakdown, but did not alter accumulation, whereas those stretched in 35 mM glucose markedly increased collagen accumulation. TGF-beta neutralization significantly reduced baseline collagen synthesis, breakdown, and accumulation in low glucose, but had no significant effect on the changes induced by stretch. In contrast, the same treatment of MC in high glucose medium greatly reduced stretch-induced synthesis and breakdown of collagen and totally abolished the increase in collagen accumulation. These results indicate that TGF-beta plays a positive regulatory role in MC collagen synthesis, breakdown, and accumulation. However, in low glucose there is no stretch-induced collagen accumulation, and the effect of TGF-beta is limited to basal collagen turnover. In high glucose media, TGF-beta is a critical mediator of stretch-induced collagen synthesis and catabolism, and, most importantly, its net accumulation. These data have important implications for the pathogenesis and treatment of diabetic glomerulosclerosis.

Animals↗

PubMed1998

[Acute otitis media with bone conduction hearing loss associated with acute mastoiditis].

Acute otitis media, generally complicated by conductive hearing loss, sometimes shows raised bone conduction thresholds. Five patients with acute otitis media with mixed hearing loss and much otorrhea were reported. The chief complaints were otalgia in 3 patients, hearing loss in 4, ear fullness in 1 and tinnitus in 1. Four patients had moderate hearing loss. At the first examination, the tympanic membrane showed swelling and injection, while 2 showed bullous myringitis, with swelling of the tympanic mucosa and a yellowish serous discharge following myringotomy. Positive mastoidal CT of all patients without acute inflammatory symptoms in the external ear suggest the complication of acute mastoiditis. After treatment with antibiotics and myingotomy for all patients, steroidal administration for 4, and tympanostomy tube insertion for 3, the hearing levels of 4 patients improved. Sensorineural hearing loss (51.3 dB) remains in 1 patient with sever hearing loss at the first examination. It is important to determine the hearing level for patients with acute otitis media, especially if it is complicated by hearing difficulties.

Acute Disease↗

PubMed1998

[Study on the relationship between tumour necrosis factor gene polymorphism and prognosis in the patients with renal cell carcinoma].

BACKGROUND: Clinical significance of polymorphism of tumour necrosis factor (TNF) genes encoded on the short arm of the 6th chromosome in the patients with renal cell carcinoma (RCC) has not been evaluated well so far. We studied on the TNF genes polymorphism of RCC focusing on the relationship between the genetic polymorphism and the prognosis. METHODS: The subjects were seventy-three patients with RCC treated at our hospitals during the past 20 years. The genomic DNA was examined by the methods of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) from frozen peripheral blood of these patients. The items examined were the genetic polymorphisms of TNF-alpha (alpha 1, alpha 2) and TNF-beta (beta 1, beta 2), and we tried to study on the prognostic outcome of RCC based upon each zygote of TNF. RESULTS: 1) The proportion of TNF-alpha and TNF-beta polymorphisms: We observed TNF-alpha 1/1 homozygote in 71 patients (97.3%). As to TNF-beta polymorphism, we observed TNF-beta 2/2 homozygote in 33 patients (45.2%), TNF-beta 1/2 heterozygote in 31 (42.5%) and TNF-beta 1/1 homozygote in 9 (12.3%). The proportion of TNF-beta polymorphism was almost the same as that of healthy Japanese. 2) PROGNOSIS: Regarding the 17-year survival, all patients with TNF-beta 1/1 homozygote were alive, and we observed a significantly favourable prognosis in the patients with TNF-beta 1/1 homozygote compared with other zygotes of TNF-beta polymorphism. The reasons for these favourable prognosis were thought that the patients with TNF-beta 1/1 homozygote showed much lower stage and/or grade than those of other zygotes. CONCLUSION: We conclude that the TNF-beta gene polymorphism is a useful marker for understanding the prognosis of RCC and a part of cellular immunity related to the tumour and its host.

Adult↗

PubMed1998

[Study on the relationship between vascular invasion and prognosis in patients with locally confined renal cell carcinoma].

BACKGROUND: There exists controversy concerning the relationship between the vascular invasion and the prognosis in the locally confined renal cell carcinoma (RCC). We have tried to study on the relationship between the vascular invasion and the prognosis in these patients. METHODS: Of the five hundred and forty-eight patients with RCC who did not have lymph node and distant metastasis, the 464 patients without having the micro- and/or macro-vascular invasion (tumour thrombus) were analysed as the control, and the remaining 85 with micro- and/or macro-vascular invasion were subject to this study. RESULTS: There observed a significantly favourable prognosis in the patients with RCC who did not have the vascular invasion (pV0) compared with the patients who had the vascular invasion (pV1a: n = 43, P = 0.00068, pV1b: n = 34, 0 < P < 0.00006, pV2: n = 8, P = 0.012). Furthermore, the patients with pV1a showed a significantly favourable prognosis compared with the patients with pV1b (p = 0.00032), and the patients with pV2 (0 < P < 0.00006), and the patients with pV1b (P = 0.00032), and the patients with pV2 (0 < P < 0.00006), and the patients with pV1b also showed a significantly favourable prognosis compared with the patients with pV2 (0 < P < 0.0006). As to the relationship between the tumour size and vascular invasion (V-stage) the tumour size got larger along with the elevation of the V-stage, and there also observed a significant difference of the tumour size between the patients with pV10 and pV1a (P = 0.00578), with pV0 and pV1b (0 < P < 0.000061) and pV0 and pV2 (P = 0.0002). The same result was obtained in the relationship between the localization of the tumour and prognosis, i.e., the patients with pV2 showed a higher frequency of larger occupation of the tumour within the kidney compared with other V-stage patients. Regarding the recurrence rate, there observed a tendency toward high frequency of recurrence along with the elevation of V-stage. Furthermore, there observed an untoward relationship between the elevation of the V-stage and the periods of recurrence after nephrectomy. In an effort to analyse the disease-free survival, there observed a significant difference among the patients with pV0, pV1a, pV1b and pV2. CONCLUSION: We conclude that the vascular invasion is a very important prognostic factor in the patients with locally confined RCC. Furthermore, along with the elevation of the V-stage, it directly reflects the poorer prognosis.

Carcinoma, Renal Cell↗

PubMed1998

[Study on the clinical characteristics of double cancers associated with renal cell carcinoma].

BACKGROUND: Clinical Features of double cancers associated with renal cell carcinoma (RCC) detected at the clinical course, especially focusing on the comparative analysis between the male and female patients, were unknown. From this background, we tried to search for clinical characteristics of double cancers associated with RCC. PATIENTS: The eight hundred and four patients with RCC have been treated at our University Hospitals and affiliated hospitals, and of them, the 38 patients (male in 25, female in 13) had double cancers during the clinical course, and these patients were objective in our study. RESULTS: 1) When we looked at all patients, there observed gastric cancer most frequently in 14 (36.8%), lung cancer in 3 (7.9%), prostate cancer in 3, bladder cancer in 3, uterine cancer in 3, rectal cancer in 2 (5.3%), thyroid cancer in 2, and pharynx, esophagus, T-cell lymphoma, chronic lymphatic leukaemia (CLL), renal pelvis, sigmoid colon, brain and colon cancers in 1 (2.6%) respectively. 2) As to the male patients, there observed 10 gastric cancers, of them, 2 died of this disease (20%), 3 lung cancers, of them, 2 died of this disease (66.7%), 3 prostate cancers, of them, 2 died of this disease (66.7%), 3 bladder cancers, of them, 1 died of this disease (33.3%), and 1 cancer patient with pharynx died of this disease, esophagus, T-cell lymphoma, CLL, renal pelvis and sigmoid colon died of this disease. Regarding the female patients, there observed 4 gastric cancers, all of them died of this disease, 3 uterine cancers, all of them died of this disease, 2 rectum cancers, all of them died of this disease, 2 thyroid cancers, of them, 1 died of this disease, 1 brain cancer and 1 rectal cancer. Furthermore, as to the timing at the detection of double cancers during the clinical course, the 10 patients (40%) detected double cancers simultaneously in male patients. On the other hand, no patient with double cancers was detected simultaneously in female patients. CONCLUSION: The gastric cancer is most frequently observed as double cancer in both of male and female patients with RCC. But, in the female patients, it shows more frequently died of double cancers associated with RCC compared with those in male. Furthermore, as to the timing at the detection of double cancer is asynchronous in all female patients with RCC.

Adult↗

PubMed1998

[Study on the combined therapy of DNA-methyltransferase inhibitor and interferon-alpha/beta for mouse spontaneously arose renal cell carcinoma, and immunological mechanism induced by the therapy].

BACKGROUND: In order to change the immunological environment of T-helper2 (Th2) predominance, namely humoural immunity, in renal cell carcinoma, we tried to examine the efficacy of combined treatment with DNA-methyltransferase inhibitor (Procainamide) and interferon (IFN)-alpha/beta in basic experiments, and also examined the immunological mechanism induced by this treatment modality. MATERIALS AND METHODS: The monotherapy of Procainamide (10 mg/kg, 20 mg/kg, 30 mg/kg, everyday for 3 weeks, i.p.) and of natural murine IFN-alpha/beta (1 x 10(4) I.U./mouse, 3 times for a week, total 9 times, s.c.), and combined treatment with these 2 drugs for mouse spontaneously arose renal cell carcinoma (RC-2) were undertaken. Furthermore, we examined the expression of cytokine mRNA related to the Th-subset in murine spleen under the tumour burden by the RT-PCR methods. RESULTS: 1) Regarding the anti-tumour efficacy of two kinds of monotherapy (Procainamide and IFN-alpha/beta), no effective result was obtained. On the other hand, the combined treatment with these two drugs induced effective anti-tumour efficacy in the relative mean tumour weight ratio (TRW/CRW), mean tumour weight and the survival rate compared with the control and each monotherapy, especially in the administration of Procainamide dosed at 30 mg/kg. As to the histological degeneration induced by the combined therapy, there still remained the viable tumour cells (grade IIb). 2) In an effort to analyse the immunological changes induced by the administration of Procainamide, there observed the expression of Th1-derived cytokines mRNA such as IFN-gamma, IL-2 and tumour necrosis factor-beta, and except for interleukin (IL)-10, there also observed the disappearance of Th2-derived cytokines mRNA such as IL-4, IL-5 and IL-6 in the murine spleen. CONCLUSION: We draw the conclusion that the treatment with DNA-methyltransferase inhibitor may change the humoural immunological environment into the cellular immunological environment enabling the effective anti-tumour efficacy combined with IFN-alpha/beta in renal cell carcinoma.

Animals↗

PubMed1998

[Participation of apoptosis in renal amyloidosis].

Renal amyloidosis shows symptoms of renal dysfunction due to the deposition of amyloid protein in the kidney. Recently, it was reported that apoptosis plays an important role in the pathogenesis of type-2 diabetes mellitus and Alzheimer's disease of which amyloid deposition is seen in the tissue. We investigated whether or not apoptosis and related factors are observed in renal amyloidosis. In situ nick end labeling (TUNEL) was performed in seven autopsied renal tissues with primary and secondary amyloidosis and 10 autopsied renal tissues without renal disease as the control. The number of TUNEL-positive cells was significantly increased in both the glomeruli and tubulus of the kidney with amyloidosis than in the control. Electron microscopic analysis was performed on one biopsied renal tissue with amyloidosis and six biopsied renal tissues with minor abnormalities as the control. Typical apoptotic cells were observed only in the former. Bax product, an inducer of apoptosis, and Bcl-2 protein, an inhibitor of apoptosis, were examined immunohistochemically in the seven autopsied renal tissues with amyloidosis and 10 autopsied control tissues. Bax was overexpressed in the tubulus and glomeruli of subjects with renal amyloidosis, compared to the normal controls. However, Bcl-2 protein was not detected in the glomeruli in any of the subjects examined. These results indicate that apoptotic cells are increased in number in renal amyloidosis and Bax overexpression may play an important role in this increase.

Aged↗

PubMed1998

[A case of primary transitional cell carcinoma of the prostate responsive to combination chemotherapy with methotrexate, epirubicin and cisplatin].

A 72-year-old man with the chief complaint of macrohematuria was referred to our hospital in February 1996. On transrectal examination, the prostate was stony hard without nodules. Cystoscopic findings and biopsies did not confirm a transitional cell carcinoma or carcinoma in situ in the bladder. However transurethral and transrectal biopsy specimens of prostate showed transitional cell carcinoma invading the prostate stroma. Pelvic CT scan revealed a lymph node metastasis in the left iliac artery region. Under the diagnosis of primary transitional cell carcinoma of the prostate, radical cystoprostatectomy and lymph node dissection were performed after two courses of neoadjuvant systemic chemotherapy. Pathologically no viable transitional cell carcinoma could be found in any of the specimens. Thus neo-adjuvant systemic chemotherapy was very effective in this case.

Aged↗

PubMed1997

Structure of cDNAs encoding human eukaryotic initiation factor 3 subunits. Possible roles in RNA binding and macromolecular assembly.

The mammalian translation initiation factor 3 (eIF3), is a multiprotein complex of approximately 600 kDa that binds to the 40 S ribosome and promotes the binding of methionyl-tRNAi and mRNA. cDNAs encoding 5 of the 10 subunits, namely eIF3-p170, -p116, -p110, -p48, and -p36, have been isolated previously. Here we report the cloning and characterization of human cDNAs encoding the major RNA binding subunit, eIF3-p66, and two additional subunits, eIF3-p47 and eIF3-p40. Each of these proteins is present in immunoprecipitates formed with affinity-purified anti-eIF3-p170 antibodies. Human eIF3-p66 shares 64% sequence identity with a hypothetical Caenorhabditis elegans protein, presumably the p66 homolog. Deletion analyses of recombinant derivatives of eIF3-p66 show that the RNA-binding domain lies within an N-terminal 71-amino acid region rich in lysine and arginine. The N-terminal regions of human eIF3-p40 and eIF3-p47 are related to each other and to 17 other eukaryotic proteins, including murine Mov-34, a subunit of the 26 S proteasome. Phylogenetic analyses of the 19 related protein sequences, called the Mov-34 family, distinguish five major subgroups, where eIF3-p40, eIF3-p47, and Mov-34 are each found in a different subgroup. The subunit composition of eIF3 appears to be highly conserved in Drosophila melanogaster, C. elegans, and Arabidopsis thaliana, whereas only 5 homologs of the 10 subunits of mammalian eIF3 are encoded in S. cerevisiae.

Amino Acid Sequence↗

PubMed1997

The translation initiation factor eIF3-p48 subunit is encoded by int-6, a site of frequent integration by the mouse mammary tumor virus genome.

Translation initiation factor eIF3 is a large, multisubunit protein complex that plays a central role in the pathway of initiation by promoting the binding of both methionyl-tRNAi and mRNA to the 40S ribosomal subunit. As part of a broad effort to elucidate the structure of eIF3, we have cloned and sequenced the human cDNA encoding the 48-kDa subunit, eIF3-p48. The recombinant protein comigrates with the authentic p48 subunit in purified eIF3 and coprecipitates with affinity-purified antibodies to the p170 subunit of eIF3. A search of the data base indicates that the mouse gene encoding eIF3-p48 had previously been identified and characterized by others as int-6. The int-6 gene is the site of frequent integration of mouse mammary tumor virus DNA into chromosomes, implicating the gene in the regulation of cell proliferation. In addition, it was shown elsewhere that the homologous human int-6 gene product binds to the human T-cell leukemia virus type I Tax protein, leading to the translocation of Int-6 to the cytoplasm. We discuss how the cytosolic function of eIF3-p48 (Int-6) in protein synthesis may account for oncogenesis caused by these two viruses.

Amino Acid Sequence↗

PubMed1997

Expression of eotaxin by human lung epithelial cells: induction by cytokines and inhibition by glucocorticoids.

Eotaxin is a potent and specific eosinophil chemoattractant that is mobilized in the respiratory epithelium after allergic stimulation. Pulmonary levels of eotaxin mRNA are known to increase after allergen exposure in sensitized animals. In this study we demonstrate that TNF alpha and IL-1beta induce the accumulation of eotaxin mRNA in the pulmonary epithelial cell lines A549 and BEAS 2B in a dose-dependent manner. Cytokine-induced A549 cell mRNA accumulation was maximal at 4 h and was significantly enhanced when the cells were costimulated with IFNgamma. TNFalpha- and IL-1beta-induced increases in eotaxin mRNA were diminished in a dose-dependent manner by the glucocorticoid dexamethasone and were augmented by the protein synthesis inhibitor cycloheximide. Cytokine-induced increases in eotaxin mRNA expression correlated with increased eotaxin protein production and secretion, and dexamethasone inhibition of cytokine-induced eotaxin mRNA augmentation was associated with diminished eotaxin protein secretion. These findings, together with the known kinetics of TNF alpha and IL-1beta mobilization in asthmatic airways and the potent eosinophil chemotactic effects of eotaxin, define a mechanism linking inflammatory cytokine mobilization to eosinophil recruitment that may be relevant to the pathogenesis of asthma.

Animals↗

PubMed1997

Selective downregulation of the angiotensin II AT1-receptor subtype in failing human ventricular myocardium.

BACKGROUND: The regulation of angiotensin II receptors and the two major subtypes (AT1 and AT2) in chronically failing human ventricular myocardium has not been previously examined. METHODS AND RESULTS: Angiotensin II receptors were measured by saturation binding of 125I-[Sar1,Ile8]angiotensin II in crude membranes from nonfailing (n = 19) and failing human left ventricles with idiopathic dilated cardiomyopathy (IDC; n = 31) or ischemic cardiomyopathy (ISC; n = 21) and membranes from a limited number of right ventricles in each category. The AT1 and AT2 fractions were determined by use of an AT1-selective antagonist, losartan. beta-Adrenergic receptors were also measured by binding of 125I-iodocyanopindolol with the beta 1 and beta 2 fractions determined by use of a beta 1-selective antagonist, CGP20712A, AT1 but not AT2 density was significantly decreased in the combined (IDC + ISC) failing left ventricles (nonfailing: AT1 4.66 +/- 0.48, AT2 2.73 +/- 0.39; failing: AT1 3.20 +/- 0.29, AT2 2.70 +/- 0.33 fmol/mg protein; mean +/- SE). The decrease in AT1 density was greater in the IDC than in the ISC left ventricles (IDC: 2.73 +/- 0.40, P < .01; ISC: 3.89 +/- 0.39 fmol/mg protein, P = NS versus nonfailing). beta 1 but not beta 2 density was decreased in the failing left ventricles. AT1 density was correlated with beta 1 density in all left ventricles (r = .43). AT1 density was also decreased in IDC right ventricles. In situ reverse transcription-polymerase chain reaction in sections of nonfailing and failing ventricles indicated that AT1 mRNA was present in both myocytes and nonmyocytes. CONCLUSIONS: AT1 receptors are selectively downregulated in failing human ventricles, similar to the selective downregulation of beta 1 receptors. The relative lack of AT1 downregulation in ISC hearts may be related to differences in the degree of ventricular dysfunction.

Adult↗

PubMed1997

Interferon gamma induces prostaglandin G/H synthase-2 through an autocrine loop via the epidermal growth factor receptor in human bronchial epithelial cells.

The induction of prostaglandin G/H synthase (PGHS; prostaglandin endoperoxide synthase, cyclooxygenase) by proinflammatory cytokines accounts, at least in part, for the altered eicosanoid biosynthesis in inflammatory diseases. In secondary cultures of normal human bronchial epithelial cells (NHBECs), interferon-gamma (IFN-gamma, 10 ng/ml for 24 h) increased the amount of prostaglandin E2 (PGE2) released in response to stimulation with exogenous arachidonic acid (5 microM). The enhanced production of PGE2 reflected the upregulation of PGHS-2 as indicated by enhanced expression of PGHS-2 RNA and increased recovery of PGHS-2 protein in NHBECs. IFN-gamma did not alter the production of PGE2 in A549 cells (a human lung adenocarcinoma cell line) or 6-keto-PGF1alpha in human umbilical vein endothelial cells (HUVECs), although prostaglandin release and/or the expression of PGHS-2 RNA in these cell lines was upregulated by other proinflammatory cytokines. Induction of PGHS-2 RNA in IFN-gamma-treated NHBECs, which peaked at 24 h, suggested the presence of an intermediary substance regulating the expression of PGHS-2. When the binding between the epidermal growth factor (EGF) receptor and its ligands was disrupted by a neutralizing antibody (LA-1), IFN-gamma failed to upregulate the release of PGE2 and the expression of PGHS-2 RNA in NHBECs. Furthermore, IFN-gamma induced the expression of RNAs for a number of ligands at the EGF receptor TGF-alpha; heparin-binding EGF-like growth factor (HB-EGF); and amphiregulin in NHBECs, and when administered exogenously, these ligands increased PGE2 release from NHBECs. Heparin at the concentration that neutralized the function of amphiregulin, or antibodies against TGFalpha or HB-EGF also reduced the release of PGE2 from IFN-gamma-stimulated NHBECs. These data are consistent with the presence of an autocrine growth factor/EGF receptor loop regulating PGHS-2 expression and PGE2 synthesis in bronchial epithelial cells.

6-Ketoprostaglandin F1 alpha↗

PubMed1997

Naturally occurring mutations in the human 5-lipoxygenase gene promoter that modify transcription factor binding and reporter gene transcription.

Five lipoxygenase (5-LO) is the first committed enzyme in the metabolic pathway leading to the synthesis of the leukotrienes. We examined genomic DNA isolated from 25 normal subjects and 31 patients with asthma (6 of whom had aspirin-sensitive asthma) for mutations in the known transcription factor binding regions and the protein encoding region of the 5-LO gene. A family of mutations in the G + C-rich transcription factor binding region was identified consisting of the deletion of one, deletion of two, or addition of one zinc finger (Sp1/Egr-1) binding sites in the region 176 to 147 bp upstream from the ATG translation start site where there are normally 5 Sp1 binding motifs in tandem. Reporter gene activity directed by any of the mutant forms of the transcription factor binding region was significantly (P < 0.05) less effective than the activity driven by the wild type transcription factor binding region. Electrophoretic mobility shift assays (EMSAs) demonstrated the capacity of wild type and mutant transcription factor binding regions to bind nuclear extracts from human umbilical vein endothelial cells (HUVECs). These data are consistent with a family of mutations in the 5-LO gene that can modify reporter gene transcription possibly through differences in Sp1 and Egr-1 transactivation.

Alleles↗

PubMed1997

Conservation and diversity of eukaryotic translation initiation factor eIF3.

The largest of the mammalian translation initiation factors, eIF3, consists of at least eight subunits ranging in mass from 35 to 170 kDa. eIF3 binds to the 40 S ribosome in an early step of translation initiation and promotes the binding of methionyl-tRNAi and mRNA. We report the cloning and characterization of human cDNAs encoding two of its subunits, p110 and p36. It was found that the second slowest band during polyacrylamide gel electrophresis of eIF3 subunits in sodium dodecyl sulfate contains two proteins: p110 and p116. Analysis of the cloned cDNA encoding p110 indicates that its amino acid sequence is 31% identical to that of the yeast protein, Nip1. The p116 cDNA was cloned and characterized as a human homolog of yeast Prt1, as described elsewhere (Methot, N., Rom, E., Olsen, H., and Sonenberg, N. (1997) J. Biol. Chem. 272, 1110-1116). p36 is a WD40 repeat protein, which is 46% identical to the p39 subunit of yeast eIF3 and is identical to TRIP-1, a phosphorylation substrate of the TGF-beta type II receptor. The p116, p110, and p36 subunits localize on 40 S ribosomes in cells active in translation and co-immunoprecipitate with affinity-purified antibodies against the p170 subunit, showing that these proteins are integral components of eIF3. Although p36 and p116 have homologous protein subunits in yeast eIF3, the p110 homolog, Nip1, is not detected in yeast eIF3 preparations. The results indicate both conservation and diversity in eIF3 between yeast and humans.

Amino Acid Sequence↗

PubMed1997

Three types of recombinant human granulocyte colony-stimulating factor have equivalent biological activities in monkeys.

Three types of rhG-CSF are commercially available (non-glycosylated: filgrastim, glycosylated: lenograstim and N-terminal mutated: nartograstim). It has been reported that higher in vitro or in vivo efficacy was found in glycosylated or N-terminal mutated rhG-CSF than in non-glycosylated rhG-CSF. We reported that glycosylated or N-terminal mutated rhG-CSF showed equal efficacy to non-glycosylated rhG-CSF in vivo. In this study, we carried out a direct comparison of pharmacokinetics and pharmacological effects of three rhG-CSFs. We used commercially obtained rhG-CSF products whose activities are guaranteed by the manufacturers. Monkeys have been selected as the experimental animals because of their close relationship to humans concerning drug disposition and daily doses were in accordance with the clinical use of rhG-CSFs. Normal cynomolgus monkeys were given 1.5 or 5 micrograms/kg of rhG-CSF either intravenously or subcutaneously for 5 consecutive days. After intravenous injection, the serum concentration-time profiles of nartograstim were almost identical to those of filgrastim at both doses but the concentrations after lenograstim administration decreased faster. Following subcutaneous administration, no marked differences were observed between the three rhG-CSFs, although lenograstim showed lower serum concentrations than both filgrastim and nartograstim. In spite of some small differences in the pharmacokinetics of the three rhG-CSFs, the pharmacodynamics were identical.

Animals↗