Phospholipid degradation in rat calcium ionophore-activated platelets is catalyzed mainly by two discrete secretory phospholipase As

An "A1 type" phospholipase activity with serine-phospholipid preference was released by rat activated platelets. It was distinct from the secretory type II phospholipase A2 [Horigome, K., Hayakawa, M., Inoue, K., and Nojima, S. (1987) J. Biochem. 101, 625-631] and co-purified with the secretory lysophosphatidylserine-selective lysophospholipase activity [Higashi, S., Kobayashi, T., Kudo, I., and Inoue, K. (1988) J. Biochem. 103, 442-447]. Several lines of evidence indicated that a single protein was responsible for the phospholipase A1 and lysophospholipase activities. Marked accumulation of lysophospholipids was observed in rat calcium ionophore-activated washed platelets and both phospholipase A1/lysophospholipase and type II phospholipase A2 were shown to contribute to this phospholipid degradation. A selective inhibitor of type II phospholipase A2 reduced the phospholipid degradation and enhanced the clotting time and prothrombinase activity. These results indicate that secretory platelet phospholipases may play a role in regulation of blood clotting.

[Evolution of aneuploidy from diploid colorectal carcinoma as revealed by the analyses of ploidy heterogeneity and Ras mutation patterns]

To analyze ploidy alterations during progression of colorectal tumors, we mapped the ploidy constitutions by cytofluorometry using (measurements of metaphase cells in) tissue sections as well as cell suspensions isolated from the tissue sections. Clonality of the tumor with heterogeneous ploidy constitution was checked by mutation pattern of K-ras codon 12. To assess the significance of polyploidy detected in the diploid tumor component, the present materials were confined to 23 tumors that contained diploid tumor cells.

RESULTS

1) Eight diploid tumors without polyploidy that invaded the submucosa or deeper were greater than 2 cm in diameter. 2) Aneuploidy was detected in tissue sections from 9 out of 15 tumors that had diploid component with polyploidy, and was occasionally predominant in the extramucosal invasive parts. 3) Near-diploid aneuploidy was detected in the cells isolated from diploid (+ polyploid) regions of 2 tumors with aneuploidy. 4) Three of the 6 tumors with heterogeneous ploidy constituents had ras mutation with the mutation patterns common to diploid and aneuploid parts. These findings suggest that aneuploid cells evolve preferentially from the diploid tumor cell population with polyploidy, which often include near-diploid aneuploidy.

[The effects of stellate ganglion block on conjunctival oxygen tension and intraocular pressure in patients with retinal vein occlusion]

We evaluated the effects of stellate ganglion block (SGB) on conjunctival oxygen tension, ocular surface temperature (n = 7) and intraocular pressure (n = 18) in patients with retinal vein occlusion and other retinopathy. The conjunctival oxygen tension (PcjO2) increased from 45.6 +/- 5.0 mmHg to 76.3 +/- 19.9 mmHg in 45 minutes by SGB and then gradually returned to the control level. PcjO2 120 minutes following SGB remained still at a higher level compared with the control value. Ocular surface temperature increased from 35.1 +/- 0.3 degrees C to 35.9 +/- 0.3 degrees C 25 minutes following SGB. Intraocular pressure decreased below the control level from 15 minutes to 120 minutes by SGB following an initial temporary increase. In conclusion, we have found that SGB does increase oxygen tension in ocular tissue and decrease IOP.

Decreases of CD4- and CD8-positive T lymphocytes in retired chromate workers

To investigate the effects of chromates on the human immune system, we measured total T lymphocytes and their two major subpopulations (CD4+ and CD8+ T lymphocytes) in the peripheral blood of 19 retired male workers who had been exposed to chromate at a chemical plant. The results indicated that both CD4+ and CD8+ T lymphocytes were significantly decreased, resulting in decreases in total T lymphocytes and total lymphocytes.

The inhibition of protein prenyltransferases by oxygenated metabolites of limonene and perillyl alcohol

The monoterpenes limonene and perillyl alcohol are effective therapeutic agents against advanced rat mammary cancer. Limonene is currently undergoing clinical testing in cancer patients. These monoterpenes and their oxygenated metabolites have been previously shown to inhibit protein prenylation in cultured cells. Since farnesylation of ras protein is critical for its ability to cause oncogenic transformation, inhibition of protein prenylation may be the basis of the anti-tumor effects of limonene and perillyl alcohol. In this study we test the ability of limonene and its oxygenated analogs to inhibit protein prenylation enzymes in vitro. Limonene and perillyl alcohol and their major in vivo metabolite, perillic acid, are weak inhibitors of both mammalian and yeast protein farnesyl transferase (PFT) and protein geranylgeranyl transferase (PGGT). In contrast, a minor metabolite of both limonene and perillyl alcohol, perillic acid methyl ester, is a potent inhibitor of both enzymes. Perillic acid methyl ester is a competitive inhibitor of yeast PFT with respect to farnesyl pyrophosphate. These studies suggest that if the inhibition of protein prenylation is a mechanism for limonene's and perillyl alcohol's anti-cancer activities, these monoterpenes may be prodrugs that are converted into pharmacologically-active substances by metabolic modification.

[A case of basilar artery occlusion caused by vertebrobasilar artery dissection presenting with mild clinical symptoms]

We reported a first case of basilar artery occlusion caused by vertebrobasilar artery dissection presenting with mild clinical symptoms. A 45-year-old female was admitted to our department due to the abrupt onset of pain in her posterior neck and occipital head, and numbness in the right upper and lower extremities. She had no other neurological complaints. Computerized tomography and magnetic resonance imaging (MRI) disclosed no abnormalities in parenchyma, but MRI revealed a linear high intensity structure in front of the medulla oblongata on T1 and T2 weighted images. Cerebral angiogram showed the pearl and string sign from the left vertebral artery to the proximal basilar artery, and showed the basilar artery occlusion, but the basilar artery distal to the occlusion site was perfused sufficiently by the carotid via posterior communicating arteries. We diagnosed it as basilar artery occlusion caused by vertebrobasilar artery dissection, which was confirmed during the operation to prevent a hemorrhage from the aneurysmal dilatation. In this case, collateral good circulation was thought to have contributed to her good clinical course.

[Cochlear microphonic potential (CM) recordable at non-shielded bedside--with reference to the development of a new earphone (NC-3)]

By making several improvements in current hearing aid earphones, a new earphone (NC-3) for CM measurement in electrocochleography (ECochG) has been developed. A silicone tube with a 1.5mm inside diameter, 175mm in length, was attached to the acoustic hole side of the earphone. The earphone proper was shielded with aluminum foil and one end of the foil was connected to a low noise cable. Human forearm was used as a dummy ear and the electrode HN-5 was fixed thereon, and a sound stimulus of 90dBnHL was delivered by the earphone (NC-3). No measurable artifacts, such as electromagnetic conductions and the CM-like mechanical vibrations generated by the acoustic output system, were recorded. By placing the earphone (NC-3) from a right-angle to a diagonal direction toward the electrode circuit, electromagnetic conduction contamination was prevented. With an extratympanic procedure using the electrode HN-5, ECochG-CM was recorded from normal hearing subjects in both a shielded sound-proof room and a non-shielded ordinary but quiet room. Short tone bursts at 1 and 4kHz were employed as acoustic stimuli and delivered by the earphone (NC-3). In the non-shielded quiet room, no electromagnetic conduction contamination or mechanical vibration was observed and there were no differences in CM responses between the two rooms. These results suggest that this earphone (NC-3), making CM recordings possible at the ordinary bedside without shielding, may contribute significantly to the subsequent spread of ECochG-CM measurement, by compensating for the disadvantages of a loudspeaker.

[Histopathological assessment of renal biopsy specimens of subjects with urine abnormality]

Between April 1985 and April 1992, 25,672 men (age 47 +/- 9 years, mean +/- SD) and 9,791 women (48 +/- 9 years) underwent mass urinalysis in the Center for Adult Complete Physical Examination in our hospital. The results revealed proteinuria in 6.3% of the men and 4.4% of the women and hematuria in 17.4% of the men and 37.8% of the women. Thirty-five subjects with asymptomatic persistent proteinuria and/or hematuria identified as a result of follow-up testing by the nephrologists at our hospital underwent renal biopsy. All of the biopsy specimens obtained were examined by light microscopy, fluorescence microscopy and electron microscopy. Histopathological findings in the biopsy specimens from these 35 subjects were as follows: One case (3%) of chronic pyelonephritis, 11 cases (31%) of IgA nephropathy, 4 cases (11%) of IgA nephropathy (severe type), 5 cases (14%) of membranous nephropathy, 4 cases (11%) of thin basement membrane disease (TMD), 7 cases (28%) of benign nephrosclerosis and 3 cases (9%) of minor glomerular abnormality. Light microscopy, fluorescence microscopy and electron microscopy for histopathological assessment of renal specimens, especially for the diagnosis of TDM, which was not uncommon, were indispensable tools in our study. Moreover, it is essential for proteinuria and hematuria to be tested simultaneously using the same standard method in all the urine specimens collected.

Effects of nitric oxide synthase inhibitor on hemodynamic change and O2 delivery in septic dogs

To elucidate the role of nitric oxide (NO) in septic shock, we measured hemodynamic and pulmonary gas changes in anesthetized dogs after intravenous administration of bacterial lipopolysaccharide (LPS) with or without NO synthase inhibitor, NG-nitro-L-arginine (L-NNA). Infusion of LPS (250 ng.kg-1.min-1) for 2 h decreased mean arterial pressure over 1-4 h. Although L-NNA (10 mg/kg) blocked LPS-induced hypotension, it decreased cardiac index, oxygen delivery index, arterial pH, and arterial PO2 and increased systemic vascular resistance index in the presence or absence of LPS. Administration of NG-nitro-D-arginine (D-NNA, 10 mg/kg) alone caused fewer hemodynamic effects (increased systemic vascular resistance index and decreased cardiac index) than L-NNA alone. Our study provides evidence that L-NNA prevents endotoxin-induced hypotension but decreases cardiac output and oxygen delivery, effects that may, in part, be due to a nonspecific NO synthase-independent event. Thus clinical use of NO synthase inhibitors for the treatment of septic shock should be cautiously considered.

Contributing factors influencing type III open tibial fractures

Ninety-five patients with severe open tibial fractures (96 fractures) were treated with nonoperative treatment alone (NO group, n = 16), immediate internal fixation (I group, n = 22), delayed internal fixation (D group, n = 34), or external fixation (EF group, n = 24). The D group was divided into a delayed internal fixation group following nonoperative treatment (D1 group, n = 14), and a delayed internal fixation group following external fixation (D2 group, n = 20). Using the classification system of Gustilo, there were 43 type IIIA, 42 type IIIB, and 11 type IIIC open tibial fractures. There were 17 deep infections (type IIIA, n = 3; IIIB, n = 12; IIIC, n = 2). The difference in the deep infection rate (DIR) between the type IIIA and type IIIB fractures was statistically significant (7.0% vs. 28.0%, p < 0.05). The DIRs in groups NO, I, D1, D2, and EF were 12.5, 27.3, 7.1, 35, and 4%, respectively. There was a significant difference in DIR between the D2 group and the EF group. The DIR in the D (D1 + D2) group and group I showed no significant difference. There was no relationship between the DIR and either Injury Severity Score or skin closure time. The authors of this study, therefore, do not feel there is an advantage to immediate internal fixation over delayed procedures for Gustilo type III open fractures of the tibia. However, careful attention must be given to the application of delayed internal fixation, especially intramedullary nailing, after external fixation.

Pathologic Assessment of Surgical Margins on Frozen and Permanent Sections in Breast Conserving Surgery

The diagnostic value of frozen section was evaluated in the histologic assessment of surgical margins obtained by wide excision of breast tumors. There were 87 patients with unilateral breast cancer, and 5 with bilateral breast cancers. The periphery of the excised breast tissue was peeled like an orange and histologically examined by frozen and permanent section. If either in situ or infiltrating microscopic tumor was found at the margin, it was considered positive. Using frozen sections, the margin was judged histologically positive or suspicious in 30 tumors (31%) and negative in 67(69%) tumors. Positive surgical margins were histologically confirmed by permanent section in 20(67%) of the 30 tumors diagnosed as positive or suspicious on frozen section. Another 10 tumors had negative margins. In 4 tumors, however, while the initial or re-excised margin was negative on frozen section, the margins were positive by permanent section. These surgical margins were positive due exclusively to the presence of ductal carcinoma in situ (DCIS). Evaluation of surgical margins in breast cancer by frozen section, thus exhibited a diagnostic accuracy of 86&prtcnt;, a sensitivity of 83%, and a specificity of 86%. It is concluded that frozen sections are useful in the determination of involvement of surgical margins after the wide excision of breast cancer. It must be pointed out that frozen sections will ofter overestimate involvement of the surgical margins.

Induction by adenovirus-5 E1A of the differentiation phenotype of F9 teratocarcinoma cells involves a conserved region (CR1) of E1A

The effects of the E1A protein of adenovirus-5 on the differentiation program of F9 teratocarcinoma cells were examined by the stable introduction of plasmids that expressed wild-type or mutated forms of E1A. Constitutive expression of plasmids for most of the mutant E1As induced loss of expression of the cell-surface antigen SSEA-1 and the enhanced expression of genes specific for the differentiated phenotype of F9 cells, such as genes for laminin B1, tissue-type plasminogen activator (tPA) and type IV collagen, as well as the altered cell morphology that is associated with the differentiated state. However, such changes were not observed in the case of genes for mutant proteins from which a conserved region (CR1) of E1A had been deleted. Furthermore, no significant induction of expression of the c-jun gene or transactivation of the c-jun-CAT reporter gene were observed when the sequence that encodes CR1 of E1A had been deleted. A palindromic sequence element (DRE) of the c-jun promoter was essential for the E1A-mediated up-regulation of the c-jun gene. These results imply that CR1 is required for activation of the c-jun gene and that it is implicated in the growth arrest, expression of parietal endoderm-specific functions and the orderly differentiation of F9 cells.

The protooncogene c-jun contains an unusual estrogen-inducible enhancer within the coding sequence

Estrogens have previously been shown to induce c-jun mRNA levels in target cells during hormone induced proliferation, and this appears to be a primary hormonal response involving transcriptional activation. In this report we have now identified an estrogen dependent enhancer within the coding sequence of c-jun. This element has the sequence GCAGAnnnTGACC which is identical to the consensus estrogen response element GGTCAnnnTGACC in the second half site, but varies considerably in the first half site. Synthetic oligodeoxynucleotides containing this jun sequence bind the estrogen receptor in cell-free studies using a competitive band shift assay with the consensus element. The jun element also confers hormone inducibility to reporter plasmids in yeast and mammalian based transcriptional systems. Structure-function studies illustrate that the TGACC half-site and its immediate flanking dinucleotides, but not the GCAGA half-site, are required for estrogen receptor binding. In contrast, both the GCAGA and TGACC half-sites are obligatory for hormone-inducible transcriptional activation. These results suggest a model in which the estrogen receptor functions as a heterodimer to regulate transcription of the c-jun protooncogene. Coupled with reports of estrogen response elements in c-fos and estrogenic induction of c-fos and c-jun in vivo, these findings also support a role for AP-1 components as early response genes in estrogen-induced proliferation.

[Spinal anesthesia for an emergency surgery in a patient with right sided heart failure]

A 79-year-old female with a pace maker implanted because of complete A-V block associated with right sided heart failure was scheduled for the emergency repair of incarcerated abdominal wall hernia. Spinal anesthesia for the surgery and epidural catheterization for postoperative pain control were performed. Anesthesia and postoperative course were uneventful. The effects of spinal anesthesia on cardiovascular system are the result of preganglionic sympathetic block produced by the local anesthetic agent injected in the subarachnoid space. It is, therefore, desirable to consider the cardiovascular effects of spinal anesthesia (reduction of afterload and preload) on a patient who has right sided heart failure. Post operative pain control by PCA pump is also a basic method for a patient with right sided heart failure.

[Quantitative analysis of individual renal function using 99mTc-DMSA scintigram--comparison with 131I-OIH renogram]

99mTc-2,3-di-mercapto-succinic acid (DMSA) is able to be used for the quantitative analysis of individual renal function by calculating the uptake ratio. The purpose of this study is to assess the clinical feasibility of DMSA uptake ratio as compared with 131I-ortho-iodo-hippuran (OIH) renogram pattern. Two hundred eleven cases (191 patients, 1 to 87 years old) with renal disorders and 4 normal volunteers (27.8 +/- 2.4 years old) were studied. Just prior to the DMSA study in the same day, OIH renogram was carried out. They were divided into 6 types by OIH renogram patterns. In 24 cases of normal renogram pattern and normal blood data who were defined as the normal group and 4 normal volunteers, DMSA uptake ratio showed negative correlation with increasing age (r = 0.61, p < 0.05). Patients of the severe impaired functioning and the non functioning patterns showed significantly decreased DMSA uptake ratios as compared with the normal pattern. There was also a significant difference in DMSA uptake between impaired functioning patterns. Compensative hemi-hypertrophy kidneys showed significantly higher DMSA uptake ratios than those of atrophic kidneys. The possibility of the quantitative analysis of the functional compensation was presumed. In conclusion, quantitative analysis of individual renal function using DMSA uptake ratio is considered to be useful to evaluate the renal functional reserve.

[Characteristics and development of stump cancers of the stomach]

To clarify characteristics and development of stump cancers of the stomach, we studied 10 cases (12 lesions) of them with mucin-histochemical and immunohistochemical techniques and gene analysis using polymerase chain reaction. Sixty-seven % of the cancers were mostly composed of gastric-type cells and 67% also showed abnormal accumulation of p53 protein in their nuclei. There were scattered cells with abnormal accumulation of p53 protein in cystically dilated glands that were often found to be surrounding cancers. Immunohistochemistry of proliferating cell nuclear antigen also demonstrated proliferating activity of these cystic glands. It is suggested that the cystically dilatated gland is precancerous lesion of stump cancers of the stomach. The gene analysis showed less occurrence of K-ras abnormality, and the mutation of APC gene is suggested to be infrequent.

Prominent uptake of Tl-201 by duodenal leiomyosarcoma after exercise myocardial perfusion study

Thallium-201 SPECT performed preoperatively for the evaluation of myocardial ischemia in a 72-year-old man with duodenal leiomyosarcoma demonstrated prominent focal uptake in the abdomen. Comparing a transaxial slice of SPECT through the abdominal uptake to the CT scan, the uptake was confirmed to be corresponding to the tumor. The tumor was delineated clearly, in good contrast to the surrounding normal intestine, which showed far less Tl-201 uptake than the tumor. In the delayed SPECT performed 3 hours after injection, although the intestinal activity became perceptible, the tumor still could be differentiated from the surrounding normal intestine. In this case, the exercise might be attributable to the initial low Tl-201 uptake by the normal intestine, which might otherwise have been an obstacle to Tl-201 scintigraphy for abdominal tumor detection. This case suggests the use of exercise for avoiding unfavorable intestinal activity, and the possibility of Tl-201 SPECT for abdominal tumor imaging.

Murine fibroblasts synthesize and secrete kininogen in response to cyclic-AMP, prostaglandin E2 and tumor necrosis factor

Fibroblasts prepared from the meninges of newborn mice or from mouse embryos, as well as fibroblast L929 cells, secreted an immunoreactive material (ir-kininogen) against rabbit anti-mouse low-molecular-weight kininogen antibody in response to dibutyryl cAMP. Western blots using a bradykinin-directed monoclonal, as well as a polyclonal anti-mouse low-molecular-weight kininogen antibody, showed that ir-kininogen had a molecular weight of 80,000 and that it contained a kinin moiety. N-terminal amino acid sequence of the ir-kininogen was consistent with that of mouse L-kininogen. The ir-kininogen produced by fibroblasts released a kinin by incubating with trypsin and mouse submandibular gland kallikrein, and it was identified as bradykinin by means of high-performance liquid chromatography, indicating that mouse fibroblasts produce and secrete a kininogen. Forskolin, prostaglandin E2 and tumor necrosis factor alpha stimulated the production of ir-kininogen by meningeal fibroblasts, whereas neither dibutyryl cAMP nor these agents influenced kininogen production by mouse hepatocytes in primary cultures. These results demonstrated that fibroblasts are a source of kininogen in the mouse, and that it is regulated by the inflammatory mediators, prostaglandin E2 and tumor necrosis factor. Therefore locally produced kininogen is implicated in pathogenesis of inflammation.

[Phase II clinical trial of the radioactive strontium (89Sr) chloride agent, SMS. 2P for pain palliation in patients with prostate cancer with bone metastases]

The phase II clinical trial of a strontium (89Sr) chloride agent (SMS. 2P) was performed in 9 patients with painful bone metastases secondary to prostate cancer. After an intravenous administration, 89Sr circulated in the plasma and was rapidly cleared. Urinary excretion varied widely among the patients. No serious acute side effects were observed. A mild transient increase in pain was reported by 4 patients 2-4 days after administration, two of whom complained of mild nausea or vomiting. All symptoms improved and never became a clinical problem. There were some abnormal hematological parameters. In particular, a decrease in the platelet level seemed to be a marrow suppression due to 89Sr irradiation. It is difficult to discriminate between the effects of 89Sr and the progress of the disease using tumor markers. The pain level improved within 2 weeks after administration and the effect continued for at least 8 weeks, which improved the quality of life for these patients.

Genes encoding RubisCO in Pseudomonas hydrogenothermophila are followed by a novel cbbQ gene similar to nirQ of the denitrification gene cluster from Pseudomonas species

The cbbL and cbbS genes, encoding ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO), were cloned and sequenced from a thermophilic hydrogen-oxidizing bacterium, Pseudomonas hydrogenothermophila strain TH-1. The cbbL gene encoded a 474-amino-acid (aa) protein (53,285 Da); cbbS encoded a 124-aa protein (14,656 Da). An ORF found downstream from the cbbLS genes encoded a 267-aa protein (29,565 Da) which had no similarity to cbbX located downstream from cbbLS from Alcaligenes eutrophus and Xanthobacter flavus. This gene, called cbbQ, was highly similar to the nirQ gene of the denitrification gene cluster from P. aeruginosa and P. stutzeri.

Effects of erythropoietin, IL-3, IL-6 and LIF on a murine megakaryoblastic cell line: growth enhancement and expression of receptor mRNAs

We examined the effects of recombinant human erythropoietin (rhEPO), recombinant murine interleukin 3 (rmIL-3), recombinant human interleukin 6 (rhIL-6), recombinant human interleukin 11 (rhIL-11), recombinant murine leukemia inhibitory factor (rmLIF) and recombinant murine granulocyte-macrophage colony-stimulating factor (rmGM-CSF) on the growth of murine megakaryocytic cell lines. In serum-free methylcellulose culture supplemented with bovine serum albumin (BSA), the addition of rhEPO (0.1-10 U/ml), rmIL-3 (10-500 U/ml), rhIL-6 (100-10,000 U/ml), rmLIF (100-10,000 U/ml), or rmGM-CSF (10-1000 U/ml) enhanced colony growth in L8057Y5 cells, which had been maintained in protein-free culture, mostly in a dose-dependent fashion; rhIL-11 did not have any stimulatory effect at the tested doses (10-1000 U/ml). In addition, colony growth of L8057 cells, which had been maintained in serum-containing culture, was enhanced, but to a lesser extent, by the addition of these cytokines except rhEPO (the cultures were supplemented with 1% fetal bovine serum. Among the cytokines that showed growth-enhancing effects on L8057 cells, the expression of mRNAs encoding receptors for EPO, IL-6 and IL-3 was examined by northern blot analysis or reverse transcription polymerase chain reaction (RT-PCR). In both cell lines, mRNAs for EPO-R, IL-6R, gp130, IL-3R alpha and beta chains were constitutively expressed. The results suggest that L8057 and L8057Y5 cell lines have characteristics of megakaryoblastic cells in their biological responses to cytokines, as well as in the expression of cytokine receptor mRNAs, and that the growth-enhancing effects of these cytokines on the cell lines may be achieved through specific receptors. Our findings show the value of these cell lines for investigating the mechanisms of growth signal transduction in megakaryopoiesis.