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Biomedical subjects

M Okazaki

Publications and source records attributed to M Okazaki.

At least 271 records · Page 15Linked to original sources

Long-term follow-up of patients with a history of near fatal episodes; can inhaled corticosteroids reduce the risk of death from asthma?

We retrospectively studied the use of inhaled corticosteroids in patients who experienced near fatal episodes (NFE) to determine whether such therapy reduces the risk of death. Forty-eight patients who had near fatal episodes of asthma between January 1981 and December 1989 were divided into two groups. Group A comprised 19 patients who received beclomethasone dipropionate (BDP) daily (mean dose of BDP:687 micrograms/day: 200-2,000) following NFE, and Group B, 28 patients who did not take BDP or who took less than 6 mg BDP/month. During the follow-up period (Group A:82.9 months, Group B:66.2 months), no patients in Group A died, but eight deaths occurred in Group B (mean period between near fatal episode and death was 31.5 months: 12-66). These results suggest that the regular use of inhaled corticosteroids, even at low doses, may reduce the risk of death in patients who experience NFE.

Acute Disease↗

Metastatic adrenocortical carcinoma treated by repeated resection: a case report of long-term survival over 18 years.

A case of recurrent and metastatic nonfunctioning adrenocortical carcinoma in a 40-year-old woman is reported. The patient received 4 laparotomies and 1 thoracotomy for recurrent and metastatic disease after removal of the primary adrenal tumor. She has been alive for over 18 years following multiple surgery for diseases after the first adrenalectomy. In selected patients with recurrence and/or metastasis, repeated surgical resection offers the possibility of a cure or extended palliation.

Adrenal Cortex Neoplasms↗

[Intra-arterial infusion chemotherapy for advanced or recurrent breast cancers].

Ideally, in preoperative intra-arterial infusion chemotherapy (regarding advanced breast cancer) is to obtain the most significant effects concerning histological features. Intra-arterial infusion chemotherapy using epirubicin (EPI), used in conjunction with daily doses of 1,200 mg medroxyprogesterone acetate (MPA), have recently been performed. This procedure has shown remarkable histological effects in the metastatic lymph nodes as well as in the primary lesions. These results were especially remarkable in the patients who were administered MPA (daily) two weeks prior to EPI infusion. These patients showed a complete disappearance of tumor cells. The results were interesting in view of the mechanism of action. Intra-arterial infusion chemotherapy combined with MPA may also be valuable in treating metastatic liver tumors and recurrent lesions in the regional lymph nodes such as supraclavicular tumors. A high response rate was obtained in the chemo-endocrine therapy when combined with MPA as a pretreatment. Thus, MPA may be expected to be available as a systemic therapy, too. In the future, a new development in the field of intra-arterial infusion chemotherapy may be achieved by utilizing a combination of angiogenesis inhibitors and peripheral blood stem cell transplantation.

Adult↗

[Concurrent chemoradiotherapy followed by surgery for advanced stage III non-small cell lung cancer (NSCLC)].

Forty-two patients with stage IIIA (bronchoscopically T3 and/or bulky N2) and stage IIIB NSCLC were treated with concurrent chemoradiotherapy (CRT). Treatment consisted of CDDP, 20 mg/m2 and etoposide, 40 mg/m2 by continuous infusion (day 1-5) of weeks 1 and 5 simultaneously with chest radiotherapy (RT), 50 Gy, 2 Gy/Fx, 5 Fx/week. Surgery was attempted 3-5 weeks after RT in pts clinically downstaged. Between 10/90 and 12/92, 43 previously untreated pts were enrolled and 42 were eligible. Pts characteristics were: male/female = 37/5; mean age, 61 yrs (range, 31-74 yrs); stage IIIA/IIIB = 10/32; 15 adenocarcinoma, 24 squamous cell, 2 large cell, 1 unclassified; PS 0/1/2 = 11/24/7. Excluding 1 ineligible pts, 42 pts were evaluated for CRT response. The response rate was 81% (1 CR, 33 PR, 5 NC, 1 PD, 2 NE). Clinical downstaging was achieved in 20 pts (48%). Twenty-one pts (50%) received surgery and 19 of them were completely resected. In 7 resection specimens, no tumor was observed. Toxicity of CRT was well tolerable (Grade 4 leukopenia, 15%; Grade 2-3 esophagitis, 15%). We conclude that this intensive combined modality therapy is acceptable and appears to increase the response rate as well as resectability. Prospective randomized studies should be conducted for further evaluation of this treatment modality.

Adult↗

[Ultrasonically guided needle biopsy of small mediastinal and peripheral pulmonary nodules].

From 1983 to 1993, we performed ultrasonically guided percutaneous needle biopsies on 320 thoracic tumors. Of these, 77 tumors were smaller than 3 cm in diameter and were peripherally located adjacent to the chest wall (n = 71) or in the posterior mediastinum (n = 6). We evaluated the efficacy and safety of UGNB for diagnosing these small lesions. The mean tumor size was 2.0 +/- 0.7 cm. Nine nodules were less than 1.0 cm in diameter, 38 were between 1.1 and 2.0 cm, and 30 were between 2.1 and 3.0 cm. Biopsies were done with a 17-gauge Trucut needle; a 21-gauge needle was used to aspirate specimens for cytological study. A definitive diagnosis was made in 31 (77%) of 40 malignant lesions and in 19 (51%) of 37 benign lesions. Complications included pneumothorax (n = 5) and hemoptysis (n = 3), but no special medications were needed. Thus, real-time sonographic guidance is a safe, easy, and reliable biopsy method for small pulmonary and mediastinal nodules adjacent to the chest wall.

Adult↗

Differential roles of two consecutive phenylalanine residues in thrombin receptor-tethered ligand peptides (SFFLRNP) in thrombin receptor activation.

A synthetic heptapeptide H-Ser-Phe-Phe-Leu-Arg-Asn-Pro-NH2, which corresponds to the ligand peptide latent in rodent thrombin receptors, was able to activate the thrombin receptor with no thrombin. In order to evaluate the structural requisites of two consecutive phenylalanines, three sets of analogs with substitutions at position either 2 or 3 were synthesized and examined for their stimulatory activity in phosphoinositide turnover in SH-EP epithelial-like cells. The replacement of Phe-2 by Ala completely eliminated the activity, while that of Phe-3 retained about 50% activity with a full stimulation. The Phe/Leu substitution resulted in a large increase (37-fold) in EC50 value for Phe-2, but in insignificant change for Phe-3. Substitution of para-fluorophenylalanine ((p-F)Phe) for Phe-2 enhanced strongly (4-fold) the activity, in contrast to a reduction by the Phe-3/(p-F)Phe substitution. Elimination of either Phe-2 or Phe-3 resulted in a complete loss of activity. These results indicated that Phe-2 and Phe-3 play different roles in the receptor activation. A highly specific aromatic phi-phi interaction was suggested between Phe-2-phenyl and thrombin receptor binding site, while Phe-3 appeared to be important for retaining a bioactive conformation.

Amino Acid Sequence↗

Establishment of new SCID and nude mouse models of human B leukemia/lymphoma and effective therapy of the tumors with immunotoxin and monoclonal antibody: marked difference between the SCID and nude mouse models in the antitumor efficacy of monoclonal antibody.

BALL-1, a human B leukemia/lymphoma cell line, was transplanted into nude and SCID mice under various conditions. The transplantation was substantially improved by preadaptation of BALL-1 by serial passages in newborn and young nude mice. We were able to establish the desirable conditions where 100% of SCID and nude mice that were inoculated i.p. with various doses of the adapted BALL-1 (termed BALL-1a) developed tumors. Tumors in SCID mice were disseminated to various tissues in a manner analogous to tumors in patients with B leukemia/lymphoma, whereas tumors in nude mice were not as widely disseminated and grew mainly as ascites. Flow cytometric analyses showed that all of the 11 tested cell surface markers of the parental BALL-1 were well maintained on the tumor cells recovered from the SCID and nude mice. The utility of the developed tumor models for the therapeutic studies was investigated by i.p. or i.v. administration of an anti-B leukemia/lymphoma monoclonal antibody, termed SN7 (IgG1 kappa), and SN7 immunotoxin (IT) that was prepared by conjugating SN7 to ricin A chain (RA) or deglycosylated RA (dgRA). In the nude mouse model study, SN7-RA that had been administered i.p. suppressed the tumor growth completely in all of the treated mice (n = 5) without any sign of tumor or undesirable side effects for as long as followed (i.e., 350 days), whereas unconjugated SN7 showed only a slight therapeutic effect. A control RA conjugate was not effective. In the SCID mouse model studies, several sets of experiments were carried out by i.p. or i.v. administration of IT, monoclonal antibody, or control IT. In the first three sets of experiments, SCID mice inoculated with 1.1 x 10(6) BALL-1a cells received an i.p. administration of phosphate-buffered saline or three different doses (i.e., 4 x 10 micrograms, 4 x 20 micrograms, and 4 x 30 micrograms) of therapeutic agents (SN7-RA and SN7). Virtually an identical result was obtained from the three experiments. All of the phosphate-buffered saline control group mice (n = 15) died within 35 days post tumor inoculation. In contrast, all of the mice that were treated with SN7-RA (n = 19) or with SN7 (n = 15) survived for as long as followed (i.e., 250 days). However, the unconjugated SN7 was less effective than SN7 IT for tumor suppression in SCID mice that were inoculated with a larger tumor burden (i.e., 4 x 10(7) BALL-1a cells).(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Hepatocellular carcinoma after transcatheter hepatic arterial embolization. A histopathologic study of 84 resected cases.

BACKGROUND: Recently, transcatheter arterial embolization (TAE) has been used to treat hepatocellular carcinoma (HCC), yet much is still unknown regarding its optimal use. METHODS: Eighty-four patients with HCC after TAE underwent surgical resection. Fifty of the tumors were less than 3 cm (small HCC [S-HCC]), and 34 were 3 cm or larger (large HCC [L-HCC]). Necrosis rate, distribution of residual HCC, histopathology of the main tumor, and proliferating activity of residual HCC by means of proliferative cell nuclear antigen (PCNA) were examined. Twenty-two randomly selected patients with HCC treated with standard chemotherapy were used as non-TAE control subjects. RESULTS: A necrosis rate of greater than 95% was seen in 35 cases of S-HCC and in 15 of L-HCC. All five nonencapsulated tumors were L-HCC and had a much lower necrosis rate. No tumors in the control group showed a necrosis rate of greater than 95%. Encapsulated tumors were categorized according to their tumor interiors, capsules, and extracapsular zones. Complete necrosis of the tumor interior was 80.0% and 35.3% in S-HCC and L-HCC, respectively. Viable residual tumors were found mainly in the extracapsular zone in S-HCC, whereas in L-HCC they were located primarily in the tumor interior. Most capsules were affected by tumor necrosis and the subsequent healing process, resulting in a thick secondary capsule. Tumor interior necrosis was uniform and coagulative in S-HCC, in contrast to L-HCC, in which necrotic regions comprised several necrosis units of differing texture and were divided by fibrous septa. In contrast, the control group revealed spotty, sparse necrosis. Non-TAE tumor capsules were thin and pathologically characteristic of those naturally occurring in tumors, as opposed to the thick fibrous capsules, which are inducible by TAE therapy. In the TAE group, the PCNA positivity rates were 37.5%, 52.5%, and 100% in Grades 1, 2, and 3/4 combined, respectively. At the tumor-nontumor boundary of the extracapsular region, PCNA-positive cells were detected in 55.0% of the cases. CONCLUSIONS: The thickened tumor capsule serves as a good postoperative indicator of TAE response. Small tumors seem to be affected in the tumor interior, whereas extracapsular invasion undermines the TAE effect. PCNA was helpful in detecting the tumor-nontumor boundary and useful as a parameter of viability of HCC after TAE.

Adolescent↗

Molecular cloning and characterization of OB-cadherin, a new member of cadherin family expressed in osteoblasts.

The preferential screening of cDNA libraries derived from the mouse osteoblastic cell line MC3T3-E1 has yielded a cDNA clone encoding 796 amino acids including the typical 24-residue-long signal sequence. The predicted amino acid sequence revealed that this protein constitutes a new member of the cadherin family. We propose the name OB-cadherin (OB for osteoblast) for this new protein. RNA analyses revealed that the OB-cadherin gene is selectively expressed in osteoblastic cell lines, precursor cell lines of osteoblasts, and primary osteoblastic cells from calvaria, as well as in lung, testis, and brain tissues at low levels. Transfection of OB-cadherin cDNA into L cells resulted in the acquisition of the Ca(2+)-dependent adhesive property. Two different forms of the human OB-cadherin cDNA were subsequently cloned; one is a counterpart of mouse OB-cadherin gene, and the other encodes a protein with a truncated cytoplasmic domain. The results suggest that the newly found OB-cadherin might have an important role in bone formation.

Amino Acid Sequence↗

Correlation of heat shock protein 70 expression with estrogen receptor levels in invasive human breast cancer.

The authors studied the role of 70-Kd heat shock protein (HSP70) in the progression of breast cancer by examining the correlation between the expression of HSP70 and epidermal growth factor receptor, c-erbB-2, p53, and estrogen receptor in 124 cases of invasive primary human breast cancers. Positivity of an anti-HSP70 monoclonal antibody, C92, was closely associated with the elevation of estrogen receptor (P < .008), whereas it inversely correlated with the expression of p53 (P < .01). In addition, the expression of HSP70 correlated inversely with the expression of epidermal growth factor receptor, although the correlation was not statistically significant (P = .06). These results suggest that the expression of HSP70 plays a role in the progression of human breast cancer.

Breast Neoplasms↗

Cloning and characterization of OSF-3, a new member of the MER5 family, expressed in mouse osteoblastic cells.

A cDNA library prepared from the mouse osteoblastic cell line, MC3T3-E1, was screened for the presence of specifically expressed genes by employing subtraction hybridization/differential screening methods. A cDNA clone was identified and sequenced, encoding a protein designated as osteoblast specific factor 3 (OSF-3) comprising 199 amino acids. RNA dot blot analysis indicated weak OSF-3 expression in thymus, spleen, brain, lung, testis, and heart, and high expression in kidney and liver. A homology search of an amino acid sequence database revealed a strong relationship of OSF-3 to the MER5 (gene preferentially expression in murine erythroleukemia cells) protein and human pag (proliferation associated gene) product. This indicates that OSF-3 plays an intrinsic role in the proliferation and/or differentiation of bone cells.

Amino Acid Sequence↗

Hydrolysis of cotton cellulose by Exo- and endo-type cellulases from Irpex lacteus: differential scanning calorimetric study.

The mode of hydrolysis of cotton cellulose by two highly purified exo- and endo-type cellulases from Irpex lacteus was investigated by differential scanning calorimetry, to measure changes in the size of the amorphous region in cotton fibers with the enzymatic reaction. The cellulases induced entirely different changes in the size of the amorphous region, particularly at earlier stages of reaction. Exo-type cellulase gradually reduced the amorphous region with release of cellobiose from the initial stage of hydrolysis, but began to increase the amorphous region at more advanced stages of hydrolysis. By contrast, endo-type cellulase caused no liberation of reducing sugar at the initial stage of hydrolysis but caused a sharp increase in the amorphous region, and it thereafter caused a rapid decrease of the amorphous region, accompanied with the production of various kinds of cellooligosaccharides. The rate of size reduction of the amorphous region caused by endo-type cellulase was much higher than that by exo-type cellulase. Convergence of the decrease in the size of amorphous region during hydrolysis by endo-type cellulase is followed by the increase in this region being influenced by further hydrolysis of remained crystalline region. Substantial changes in the morphology of cotton occurred with the two cellulases after the hydrolysis stages at which the size of the amorphous region was minimum.

Calorimetry, Differential Scanning↗

Alpha 1 adrenergic receptor-induced c-fos gene expression in rat aorta and cultured vascular smooth muscle cells.

While growth of blood vessels is important in hypertension, relatively little is known about the contribution of catecholamines. Using isolated rat aorta and cultured smooth muscle cells, we examined adrenergic stimulation of gene expression. Phenylephrine, a selective alpha 1 adrenergic receptor agonist, caused a rapid and transient increase in c-fos mRNA accumulation which was inhibited by prazosin, an alpha 1 receptor antagonist. Similarly, phenylephrine stimulated c-jun and c-myc mRNA accumulation. Chloroethyl-clonidine, a compound which irreversibly blocks alpha 1B receptors, completely blocked the phenylephrine-induced increase in c-fos mRNA. RNase protection experiments demonstrated that rat aorta prominently expressed mRNA for alpha 1B and alpha 1A/D receptors. Phenylephrine-induced c-fos mRNA was partially inhibited by H-7, a protein kinase C inhibitor, and by nifedipine, a Ca2+ channel blocker; these two compounds together had additive effects. In situ hybridization showed that expression of c-fos mRNA induced by phenylephrine was localized to aorta's medial layer. These results suggest that alpha 1 receptor-induced increase in c-fos mRNA in aorta is mediated by a chloroethyl-clonidine-sensitive receptor subtype signaling via increasing intracellular Ca2+ concentrations and activating protein kinase C.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

Enhancement of cytokine production by macrophages stimulated with (1-->3)-beta-D-glucan, grifolan (GRN), isolated from Grifola frondosa.

The ability of grifolan (GRN), a purified fungal (1-->3)-beta-D-glucan, to induce various cytokines from macrophages was examined in vitro. Interleukin-6 (IL-6) activity in supernatants from the culture of macrophage cell line, RAW264.7 was dependent on increasing doses of GRN. The level of IL-6 induced with 500 micrograms/ml of GRN was comparable to that induced with lipopolysaccharide (LPS) 10 micrograms/ml. Enhancement of the mRNA level of IL-6 by treatment with GRN was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). The effect of GRN on production of IL-6 was also observed using peritoneal macrophages from C3H/HeJ mice which did not respond to endotoxins. This data suggested that the ability of GRN to activate IL-6 production of macrophages is not due to contamination of endotoxins in the preparation. Enhanced production of cytokine by GRN was observed not only with IL-6, but also with interleukin-1 (IL-1) and tumor necrosis factor alpha (TNF alpha). In the production of TNF alpha, GRN was more effective than LPS used in this study. Other soluble or gel-forming(1-->3)-beta-D-glucans from various sources did not enhance the production of such cytokines although they are structurally similar to GRN. The above results indicate that GRN is a novel macrophage activator which augments cytokine production without dependence on endotoxins.

Adjuvants, Immunologic↗