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Biomedical subjects

N Hosokawa

Publications and source records attributed to N Hosokawa.

At least 37 records · Page 2Linked to original sources
PubMed1999

Separate cis-acting DNA elements control cell type- and tissue-specific expression of collagen binding molecular chaperone HSP47.

HSP47 is a collagen-binding heat shock protein and is assumed to act as a molecular chaperone in the biosynthesis and secretion of procollagen. As the synthesis of HSP47 is closely correlated with that of collagen in various cell lines and tissues, we performed a promoter/reporter assay using HSP47-producing and nonproducing cells. 280 base pairs (bp(s)) of upstream promoter were shown to be necessary for the basal expression but not to be enough for the cell type-specific expression. When the first and the second introns were introduced downstream of this 280-bp region, marked up-regulation of the reporter activity was observed in HSP47-producing cells but not in nonproducing cells. This was confirmed in transgenic mice by staining the lacZ gene product under the control of the 280-bp upstream promoter and the introns. Staining was observed in skin, chondrocytes, precursor of bone, and other HSP47/collagen-producing tissues. A putative Sp1-binding site at -210 bp in the promoter, to which Sp3 and an unidentified protein bind, was shown to be responsible for this up-regulation when combined with the introns. However no difference in the binding to this probe was observed between HSP47-producing and nonproducing cells. The responsible region for cell type-specific up-regulation was found to be located in a 500-bp segment in the first intron. On electrophoresis mobility shift assay using this 500-bp probe, specific DNA-protein complexes were only observed in HSP47-producing cell extracts. These results suggest that two separate elements are necessary for the cell type-specific expression of the hsp47 gene; one is a putative Sp1-binding site at -210 bp necessary for basal expression, and the other is a 500-bp region within the first intron, required for cell type-specific expression.

3T3 Cells↗
PubMed1999

The human genome has only one functional hsp47 gene (CBP2) and a pseudogene (pshsp47).

Among all the species investigated to date, only in humans is hsp47 reported to exist as two separate genes. Here we examined whether hsp47 forms a gene family, and if so, how many genes constitute the family. Cloning and sequencing of human hsp47 cDNA revealed that only one gene, identical to CBP2, was transcribed. No transcript corresponding to colligin, which was reported to be a human homologue of hsp47, was found. Genomic southern hybridization using the exon III fragment of mouse hsp47 as a probe, however, showed two bands for several restriction enzyme digests. We cloned and sequenced the gene corresponding to the extra band and found that a pseudogene (pshsp47) existed in the human genome. We have mapped this pseudogene to chromosome 9p12-p13 by fluorescent in situ hybridization (FISH) using a 3.5kb genomic fragment containing the entire pshsp47 sequence as a probe. These results suggested that functional hsp47 exists as CBP2, not as colligin, and a highly conserved pseudogene is present in the human genome.

Base Sequence↗
PubMed1999

Futalosine and its derivatives, new nucleoside analogs.

Futalosine, a new nucleoside analog, was isolated from a fermentation broth of Streptomyces sp. MK359-NF1. Some chemical derivatives of futalosine were prepared. 6-O-Methylfutalosine methylester inhibited growth of HeLa-S3 cells in vitro (IC50 = 19.5 micrograms/ml) in contrast to the weak activity of futalosine. 6-O-Methylfutalosine methylester at concentrations higher than 10 micrograms/ml inhibited incorporation of 3H-TdR and 3H-UR but not 3H-Leu in the acid-soluble fractions of HeLa-S3 cells.

Antibiotics, Antineoplastic↗
PubMed1999

Effect of thiazinotrienomycin B, an ansamycin antibiotic, on the function of epidermal growth factor receptor in human stomach tumor cells.

Thiazinotrienomycin B (TT-B), an ansamycin isolated from fermentation broths of Streptomyces sp. MJ672-m3, inhibited the growth in vitro of human stomach tumor SC-6 cells over 10 times more strongly than the growth of other human tumor cells, such as HeLa (cervix), T24 (bladder) and LX-1 (lung). The extent of growth inhibition by TT-B of SC-6, but not of LX-1 nor T24, was lowered in a competitive manner by raising serum concentrations in the culture medium. TT-B inhibited the cell cycle progression of SC-6 at an early stage of the progression from G0/G1 to S. The inhibition was again competitive with serum concentrations in the culture medium. No direct inhibition of DNA synthesis was observed at the concentration range which caused the cell cycle arrest. TT-B and anti-epidermal growth factor receptor (anti-EGFR) were antagonistic to each other in inhibiting the cell cycle progression of SC-6 from G0/G1 to S, suggesting that the two compounds share the same target, EGFR. The kinase activity of EGFR was little inhibited by TT-B in a cell-free system.

Anti-Bacterial Agents↗
PubMed1999

[Quantitative study of 99mTc-Technegas SPECT for ventilatory impairment in pulmonary emphysema].

99mTc-Technegas scintigraphy is used to evaluate ventilation abnormalities in patients with pulmonary emphysema. Although abnormalities of ventilation distribution are easy to find, no objective index exits. Evaluation is subjective and differs with each radiologist. Thus, it is difficult to compare cases and the clinical course in the same case. The present study for quantitative evaluation demonstrated an excellent correlations between mean voxel values of the lung and stage classification. Furthermore, a correlation was observed between the mean and FEV1.0%. These findings indicate that the quantitative analysis of SPECT data is useful for classifying clinical stage and comparing cases.

Humans↗
PubMed1999

[Clinical analysis of Pseudomonas aeruginosa bacteremia].

UNLABELLED: To determine the outcome of Pseudomonas aeruginosa bacteremia and to identify risk factors for these infections in our University hospital, 46 cases (65 episodes) of Pseudomonas aeruginosa bacteremia were retrospectively investigated. The most frequent underlying diseases or cases were from Emergency and Critical care center (18 cases, including 11 case of cerebrovascular accident and head injury) followed by hematologic malignancies (11 cases) but none of the HIV infection was included in this study. The overall crude mortality rate was 50% and mortality rate within the first 1 week was 17%. Clinical analysis of those cases revealed that possible risk factors were neutropenia, sever sepsis and prior use of antibiotics (antipseudomonal antibiotics were administered before positive blood culture episodes in 90% cases). But these factors were not statistically significant between dead and survived cases. CONCLUSION: To improve the prognosis of Pseudomonas aeruginosa bacteremia, we must change the management of the hospital infection, such as the more rational use of new antipseudomonal antibiotics and the more clean and reasonable management of central venous catheters.

Adolescent↗
PubMed1998

Transcriptional activation of the mouse HSP47 gene in mouse osteoblast MC3T3-E1 cells by TGF-beta 1.

HSP47 is a 47-kDa collagen-binding heat shock protein, the expression of which is always correlated with that of collagens in various cell lines. We examined the effects of TGF-beta 1, which is reported to induce the collagen genes, on the expression of HSP47 in mouse osteoblast MC3T3-E1 cells. Treatment of the cells with 5 ng/ml TGF-beta 1 for 24 h increased the level of HSP47 mRNA three-fold. Dose-dependent induction by TGF-beta 1 was observed for both HSP47 mRNA and collagen alpha 1 (I) mRNA, and actinomycin D inhibited this increase of HSP47 mRNA. To elucidate the TGF-beta 1 responsive element(s) in the mouse HSP47 gene, we generated a series of 5'-deletion promoters fused to luciferase reporter constructs. Transient transfection assays showed that TGF-beta 1 induced 4-6 fold the promoter activity of a region approximately -5.5 kbp upstream of the HSP47 gene. Two upstream regions, -3.9 to -2.7 kbp and -280 to -50 bp were shown to be involved in the activation in response to TGF-beta 1 treatment.

3T3 Cells↗
PubMed1998

HSP47, a collagen-specific molecular chaperone, delays the secretion of type III procollagen transfected in human embryonic kidney cell line 293: a possible role for HSP47 in collagen modification.

HSP47 is a stress protein (heat shock protein) which resides in the endoplasmic reticulum, and is postulated to function as a collagen-specific molecular chaperone. To elucidate the role of HSP47 in procollagen biosynthesis, we have established human embryonic kidney 293 cell lines, which were stably transfected with alpha1(III) procollagen chains with or without HSP47. 293 cells do not produce any extracellular matrix proteins including collagens, and the level of HSP47 expression is almost undetectable in this cell line. Recombinant type III procollagens in 293 cells form trypsin-resistant homotrimers, which are secreted into the medium as trimers in the presence or absence of recombinant mouse HSP47. The secretion of procollagen III was delayed in 293 cells stably transfected with proalpha1(III) collagen chains [293+proalpha1(III) cells] in comparison with human rhabdomyosarcoma cell line RD, which normally produces type III procollagens. In this study, we examined the rate of type III procollagen secretion in detail. In cells cotransfected with mouse HSP47 [293+proalpha1(III)+HSP47 cells], the rate of type III procollagen secretion was slower than in 293+proalpha1(III) cells. The binding of HSP47 with proalpha1(III) collagen chains was confirmed by immunoprecipitation using the chemical cross-linker, DSP. The electrophoretic mobility of proalpha1(III) collagen chains in 293+proalpha1(III) cells was slightly slower than that in RD cells, whereas the recombinant proalpha1(III) chains of 293+proalpha1(III)+HSP47 cells showed almost the same electrophoretic mobility as those of RD cells. The melting temperature (Tm) of type III procollagen in 293+proalpha1(III)+HSP47 cells was almost the same as that in RD cells, and the Tm in 293+proalpha1(III) cells was slightly higher than that in RD cells. These data suggest that the recombinant proalpha1(III) collagen chain is overmodified in 293+proalpha1(III) cells, but not in 293+proalpha1(III)+HSP47 cells.

Animals↗
PubMed1998

Expression and localization of collagen-binding stress protein Hsp47 in mouse embryo development: comparison with types I and II collagen.

Heat shock protein (Hsp)47 is a collagen-binding stress protein localized in the endoplasmic reticulum and is thought to have chaperone-like functions that are specific to procollagen biosynthesis. In previous papers, we reported that the expression of Hsp47 is closely correlated with that of various types of collagen in various cell lines and also in the progression of experimental liver fibrosis. In the present study, the expression of Hsp47 was examined during the development of mouse embryos by immunostaining with an anti-Hsp47 antiserum. The spatio-temporal correlation of the expression of Hsp47 with those of types I and II collagen was also examined using specific antisera. Hsp47 expression during embryogenesis was observed mainly in mesoderm and in tissues that are derived from mesoderm, such as connective tissue, cartilage, bone, notochord and somites. Hsp47 was also detected in tissues derived from the neural crest mesenchyme. In the central nervous system, Hsp47 was detected in some restricted regions where cells proliferate, such as the ventral area of the neural tube and choroid plexus. Immunostaining for types I and II collagen revealed the spatial and temporal correlations of the expression of these proteins with that of Hsp47. These results suggest the biological importance of Hsp47 as a collagen-specific molecular chaperone in the mouse developmental program.

Animals↗
PubMed1997

[Three cases of malignant lymphoma that developed from the chest wall].

Chronic tuberculous pyothrax and the development of non-Hodgkin's lymphoma (NHL) on the chest wall are believed to be closely related. We encountered three patients with NHL involving the chest wall in whom the tumor may have had a different origin Patient 1: A 65-year-old man with a history of pulmonary tuberculosis and right-sided pyothrax at the age of 28 years was found to have a tumor on the right sided of the chest wall, and NHL was diagnosed. Patient 2: A 65-year old woman with a history of right-sided tuberculous pyothrax at the age of 2 years had a left-sided chest-wall tumor, and NHL was diagnosed. Patient 3: A 78-year-old man with a history of tuberclous pleuritis on the left side at the age of 77 years was found to have a left-sided chest-wall tumor, and NHL was diagnosed. In patients 1 and 2, the Epstein-Barr virus was found in tissue specimens by in situ hybridization. These findings suggest that chronic tuberculous pyothrax and the development of NHL on the chest wall were not closely related in these patients, and that the Epstein-Barr virus may play an important role in the development of NHL on the chest wall after tuberculous pyothrax.

Aged↗
PubMed1996

Intracellular interaction of collagen-specific stress protein HSP47 with newly synthesized procollagen.

Heat shock protein 47 (HSP47), a collagen-specific stress protein, has been postulated to be a collagen-specific molecular chaperone localized in the ER. We previously demonstrated that HSP47 transiently associated with newly synthesized procollagen in the ER (Nakai, A., M. Satoh, K. Hirayoshi, and K. Nagata. 1992. J. Cell Biol. 117:903-914). In the present work, we examined the location where HSP47 binds to and dissociates from newly synthesized procollagen within the cells, and whether HSP47 associates with nascent single procollagen polypeptide chains and/or with mature triple-helix procollagen. This was accomplished by biochemical coprecipitation with anti-HSP47 and anticollagen antibodies, combined with pulse-label and chase experiments in the presence or absence of various inhibitors for protein secretion, as well as by confocal laser microscopic observation of the cells double stained with both antibodies. We further examined whether the RDEL (Arg-Asp-Glu-Leu) sequence at the COOH terminus of HSP47 can act as an ER-retention signal, as the KDEL sequence does. When the secretion of procollagen was inhibited by the presence of alpha, alpha'-dipyridyl, an iron chelator that inhibits procollagen triple-helix formation, or by the presence of brefeldin A. which inhibits protein transport between the ER and the Golgi apparatus, procollagen was found to be bound to HSP47 during the chase period in the intermediate compartment. In contrast, the dissociation of procollagen chains from HSP47 was not inhibited when procollagen secretion was inhibited by monensin or bafilomycin A1, both of which are known to be inhibitors of post-cis-Golgi transport. These findings suggest that HSP47 and procollagen dissociated between the post-ER and the cis-Golgi compartments. HSP47 was shown to bind to nascent, single-polypeptide chains of newly synthesized procollagen, as well as to the mature triple-helix form of procollagen. HSP47 with the RDEL sequence deleted was secreted out of the cells, which suggests that the RDEL sequence actually acts as an ER-retention signal, as the KDEL sequence does. This secreted HSP47 did not acquire endoglycosidase H resistance. The biological significance of the interaction between HSP47 and procollagen in the central secretory pathway, as well as possible mechanisms for this pathway, will be discussed.

2,2'-Dipyridyl↗
PubMed1996

Hydroxymycotrienins A and B, new ansamycin group antibiotics.

New ansamycins designated hydroxymycotrienins A and B were isolated from culture broths of Bacillus sp. BMJ958-62F4. The two antibiotics inhibited more strongly the growth of human cervical cancer cell lines of human papilloma virus (HPV) positive than that of HPV negative cell lines. The structures, some biological and biochemical properties are reported.

Anti-Bacterial Agents↗
PubMed1995

Hypersensitivity pneumonitis in a pearl nucleus worker.

A 37-year-old woman had worked for 4 years in a shell-processing factory where considerable airborne dust was produced cutting and polishing fresh water shells into pearl nuclei. She had a dry cough and dyspnea. Transbronchial lung biopsy showed noncaseating granulomas and cellular intraalveolar infiltrates. High-resolution lung computed tomography (HRCT) showed diffuse small nodules and ground-glass opacities. Hypersensitivity pneumonitis caused by shell dust should be considered in the appropriate clinical setting in a patient with the appropriate radiographic abnormalities.

Adult↗
PubMed1995

Thiazinotrienomycins, new ansamycin group antibiotics.

New triene-ansamycins designated thiazinotrienomycins A, B, C, D and E were isolated from culture broth of Streptomyces sp. MJ672-m3 for their activities against cervical cancer cell lines. The structures and some biological and biochemical properties of the antibiotics were determined.

Animals↗
PubMed1995

[Prediction of postoperative pulmonary function using 99mTc-MAA perfusion lung SPECT].

In order to predict postoperative pulmonary function, 99mTc-MAA perfusion lung SPECT and spirometry were performed preoperatively in 52 patients with resectable primary lung cancer; 44 underwent lobectomy, eight pneumonectomy. Local pulmonary function (called local effective volume) was evaluated according to the degree of radionuclide distribution of each voxel in the SPECT images. The total effective volume was defined as the sum of the local effective volume, and the residual effective volume was the total effective volume excluding loss after operation. Predicted pulmonary function (VC and FEV1.0) was calculated by the following formula: Predicted value = preoperative value x percent of the residual effective volume. Postoperative pulmonary function was predicted in the same patients by means of 99mTc-MAA perfusion lung planar scintigraphy and X-ray CT. The patients were reinvestigated with spirometry at one and four months after surgery, and the values were compared with the predicted values. The correlations between the predicted values using SPECT and measured postoperative pulmonary function were highly significant (VC: r = 0.867, FEV1.0: r = 0.864 one month after operation; VC: r = 0.860, FEV1.0: r = 0.907 4 months after operation). The predicted values calculated using SPECT were accurate compared with the predicted values calculated using planar scintigraphy or X-ray CT. The patients with predicted FEV1.0 of less than 0.8 liter required home oxygen therapy. This method is valuable for the prediction of postoperative pulmonary function before the surgical procedure.

Adult↗
PubMed1994

[Results of radiotherapy for stage III uterine cervical carcinomas and preliminary study of combined radiotherapy and transarterial infusion chemotherapy].

This is a retrospective analysis of 55 patients with stage III carcinoma of the uterine cervix treated with radiation from November 1984 through December 1991. Eleven of the patients were treated with radiation and transarterial infusion chemotherapy (TAI), using cis-platinum and pepleomycin. The 3- and 5-year cumulative survival rates for all patients were 61% and 58%, respectively, and the 3-year cumulative survival rate for the group with combined radiation and TAI was 47%. According to initial failure site, the locoregional recurrence rate was 36.8%, and that for para-aortic lymph node metastasis and distant metastasis was 31.6%. The failure pattern was similar between the irradiation only group and the group with combined radiation and TAI. The incidence of intestinal complications of grades 1 and 2 was 20%. Irradiation combined with TAI did not increase the incidence of complications.

Adult↗