Successful surgical management for multiple cerebral mycotic aneurysms involving both carotid and vertebrobasilar systems in active infective endocarditis

Mycotic aneurysm is usually found in the middle cerebral artery associated with infective endocarditis. Previous reports we have identified include only 4 cases of vertebrobasilar aneurysm. We report on a 29-year-old female who had multiple mycotic aneurysms involving both the carotid and vertebrobasilar systems complicated by intracranial hemorrhage with infective endocarditis, in whom staged operations, mitral valve replacement and craniotomies, were successfully performed.

[A successful case of valve-sparing surgery for tricuspid valve endocarditis]

A successful repair for infective endocarditis of the tricuspid valve is presented. A 35-year-old man was referred to our hospital complaining of high fever despite antibiotic chemotherapy. Lung scan showed multiple thromboembolism. Blood cultures revealed staphylococcus aureus. Echocardiography showed vegetations attached to the tricuspid valve and severe tricuspid regurgitation. Conservative surgery such as vegetectomy and DeVega's annuloplasty was successfully carried out. The patient's postoperative course was uneventful. The conservative surgery might provide a satisfactory result in the selected cases with localized vegetation and minimum valve involvement.

[A case of impending rupture of acute aortic dissection with thrombosed false lumen in early phase]

A 73-year-old patient with acute aortic dissection in delayed shock state following sudden onset of chest-back pain and left sided hemothorax was successfully operated. Contrast enhanced CT demonstrated a crescent-shaped low density area in the descending aorta. Aortography showed ulcer-like projection (ULP) with minor leakage into left thorax, however, a flow in false lumen was not visualized. These findings suggested that the false lumen of type III aortic dissection was thrombosed in its early phase. The aneurysm was transected on left heart bypass through left thoracotomy. The entry of false lumen was found in proximal portion of descending aorta, in which fresh thrombus was filled. A graft was anastomosed and reinforced with felt strips in end-to-end. The postoperative course was uneventful. The ULP by aortography provides a possible sign of rupture in clinical course of aortic dissection.

Identification of the specific labile sites in the 180 kDa catalytic polypeptide of the Drosophila melanogaster DNA polymerase alpha-primase complex

The immunoaffinity-purified DNA polymerase alpha-primase complex from Drosophila melanogaster Kc cells contains three high molecular weight polypeptides besides the 180 kDa catalytic polypeptide. These polypeptides are immunologically cross-reactive with the 180 kDa polypeptide. When the immunoaffinity-purified complex was kept at 4 degrees C for about four weeks, the amounts of the three polypeptides increased, while the 180 kDa polypeptide completely disappeared. Sodium bisulfite inhibited the decrease in the 180 kDa polypeptide. The N-terminal amino acid sequences of all the polypeptides were all assigned to ones present in a portion close to the N-terminus of the 180 kDa polypeptide. The N-terminal residue of all the three polypeptides was Ser. The cleavage sites were Phe130-Ser131, Thr180-Ser181, and Phe237-Ser238. These results show that the three polypeptides are cleavage products of the 180 kDa catalytic polypeptide, the cleavage occurring at specific labile sites including a Ser residue. The amino acid residues at the sites are quite different from those (Lys-Lys) in the human 180 kDa catalytic polypeptide.

Cytotoxic and cytostatic effects of polyphenols against rat 3y1 fibroblasts transformed by e1a gene of human adenovirus-type-12

Toxicity of polyphenols against rat 3Y1 fibroblasts and the cells transformed by human adenovirus (Ad12-3Y1), its EIA gene (EIA-3Y1), or simian virus 40 (SV-3Y1) was examined. Among the diphenol compounds examined, pyrocatechol (o-diphenol) and hydroquinone (p-diphenol) showed selective toxicity against Ad12-3Y1 and EIA-3Y1 cells, while resorcinol (m-diphenol) showed a much weaker non-specific toxicity against these cells. Another o-diphenol (dopamine) and triphenols (gallic acid and pyrogallol) were less toxic but showed selective toxicity. At lower concentrations where they were not toxic, all polyphenols attenuated toxicity of phosphatidylcholine against EIA-3Y1 cells. Among antioxidants examined, ascorbic acid reduced the toxicity of pyrocatechol, but alpha-tocopherol and butyrated hydroxytoluene did not. Oxidation of pyrocatechol was not enhanced in the presence of 3Y1 or EIA-3Y1 cells and their homogenates. These results suggest that the selective toxicity of polyphenols against Ad12-3Y1 and E1A-3Y1 cells is not related to their oxidation velocity but other factors such as the activity of active oxygen-scavenging enzymes.

Etiopathogenesis of feline dental resorptive lesions

There are several factors in the etiopathology of feline resorptive lesions. They may be considered as local immune-response mediating cell and humoral factors; release of biochemical components in dental and paradental tissues to attract odontoclasts; mechanical stress, including occlusal mechanism; and local and systemic calcium regulation, including remodeling of mineralized tissue and dietary intake of calcium.

Functional analysis of nucleosome assembly protein, NAP-1. The negatively charged COOH-terminal region is not necessary for the intrinsic assembly activity

A nucleosome assembly protein (NAP-1) of Saccharomyces cerevisiae facilitates the association of histones with DNA to form nucleosomes in vitro at physiological ionic conditions. The cloned gene was expressed in Escherichia coli using a T7 expression system, and the protein (417 amino acid residues) was purified by Mono Q column chromatography. Various deletion fragments of NAP-1 protein were also produced, and their nucleosome assembly activity was examined by supercoiling assay. The internal fragment containing the residues 43-365 was necessary and sufficient for the activity, and a long stretch of negatively charged region near the carboxyl terminus was dispensable. This minimal size fragment could form the 12 S NAP-1-histone complex as the whole protein could, whereas deleted fragments on either side could bind with core histones only to form aggregates.

Analysis of glutathione transferase P gene regulation with liver cells in primary culture

Glutathione transferase P (GST-P) gene is specifically and highly activated during rat chemical hepatocarcinogenesis. We have previously cloned the GST-P gene and have identified putative regulatory regions. To further explore regulatory mechanisms, deletion constructs of the GST-P gene fused to the chloramphenicol acetyltransferase (CAT) structural gene were introduced into primary cultured rat hepatocytes by electroporation, and their activity was determined. The expression of the GST-P-CAT fusion gene is quite low in these cells as compared to that in both a rat fibroblast cell line, 3Y1 cells, and a rat hepatoma cell line, dRLh84. The presence of the strong enhancer GPEI did not elicit any enhancing activity at its original position, or when it was located 3' of the CAT gene, although this element does enhance CAT activity significantly when located adjacent to the promoter. Cotransfection of neither c-jun nor c-fos expression vector, nor both vectors, could enhance the CAT activity, even though GPEI consists of two phorbol ester response element-like sites. Furthermore, the expression of jun family gene was not correlated with GST-P gene expression either in primary cultured hepatocytes or in hepatoma cell lines.

Induction of DNA synthesis by fibroblast growth factor in temperature-sensitive cell-cycle mutants of rat 3Y1 fibroblasts arrested at restrictive temperature

Four temperature-sensitive cell-cycle mutants of rat 3Y1 clonal fibroblasts representing separate complementation groups (3Y1tsD123, 3Y1tsF121, 3Y1tsG125 and 3Y1tsH203) are arrested at restrictive temperature, primarily with a G1-phase DNA content (temperature arrest). We examined various factors affecting signal transduction for activity which induces DNA synthesis at the restrictive temperature when added to the temperature-arrested cultures of these mutants. The factors examined were theophylline, dibutyryl cyclic AMP, cholera toxin (CT), dibutyryl cyclic GMP, sodium nitroprusside, phorbol 12-myristate 13-acetate, 1-oleoyl 2-acetylglycerol, bombesin, vasopressin, basic fibroblast growth factor (FGF), platelet-derived growth factor, A23187, monensin, epidermal growth factor (EGF), insulin and fetal calf serum (FCS). None of these factors induced DNA synthesis in 3Y1tsH203. In one mutant (3Y1ts121), FGF, EGF and FCS individually induced DNA synthesis. In the other 2 mutants (3Y1tsD123 and 3Y1tsG125), FGF and CT individually induced DNA synthesis. The FGF-induced DNA synthesis was suppressed by islet-activating protein (IAP) in 3Y1tsD123 and 3Y1tsG125, but not in 3Y1tsF121. The CT-induced DNA synthesis was also suppressed by IAP, as previously shown. When temperature-arrested cultures were shifted to a permissive temperature, all 4 mutants initiated DNA synthesis in the presence of IAP. These results suggest that (1) a cell can prepare for the initiation of DNA synthesis by using several independent signal transduction pathways, and (2) in a given situation, the cell uses a particular pathway because of its availability, which depends on the culture conditions.

[A successful case of concomitant operation for coronary artery disease and rectal cancer in elderly patient]

We report a successful case of 75-year-old man who was simultaneously undertaken CABG for coronary artery disease and Miles' operation for rectal cancer. A concomitant cardiac and rectal operation involves serious problems, such as increasing operative risk, bleeding tendency after cardiopulmonary bypass, infection and radicality against malignancy, however, it should be a definitive method for the selective case.

[A case report on a double chambered right ventricle (DCRV)--pre- and postoperative responses of the right ventricle to atrial pacing and the isoproterenol tolerance test]

To evaluate the development of an anomalous muscle bandle of the right ventricle (RV) and results of surgical intervention, responses of the RV to atrial pacing and the isoproterenol tests were examined in both the pre- and postoperative periods. Although cardiac output did not increase in proportion to the rate of atrial pacing or the dose of isoproterenol, the pressure gradient through the RV increased abnormally from 38 mmHg to 59 mmHg (atrial pacing) and 116 mmHg (isoproterenol). On the other hand, postoperative evaluation showed normal RV responses in these tests. Since the response of the right ventricle to these tolerance tests in patients with DCRV in pre- and postoperative periods has not been well elucidated, a precise evaluation is reported in this paper.

Case report: diagnosis of cavo-portal shunt in inferior vena cava obstruction: comparison between venography and dynamic scintigraphy

A cavo-portal shunt is a rare complication of inferior vena cava obstruction. A patient is described who had complete obstruction of the inferior vena cava (IVC) due to extension of tumour thrombus from a left renal cell carcinoma. Venocavography clearly showed many collateral veins but not a cavo-portal shunt. Dynamic scintigraphy, however, distinctively showed a draining vein and subsequent homogeneous radionuclide uptake of the liver, which indicates a cavo-portal shunt.

Silencer binding proteins function on multiple cis-elements in the glutathione transferase P gene

The glutathione transferase P (GST-P) gene is specifically expressed during chemical hepatocarcinogenesis of the rat, whereas mRNA of this gene is virtually undetectable in normal liver. We have previously identified a stretch of DNA, that acted negatively in transcription, at 400 bp upstream from the cap site of the rat GST-P gene. Further characterization has revealed that this negative fragment functions in an orientation and position independent manner, suggesting that it is acting as a silencer. This silencer consists of multiple negative elements to which nuclear factors bind. This silencer is active not only in rat non-hepatoma and hepatoma cells but also in human and mouse cell lines, suggesting that these elements function as general regulators of basal gene expression. At least two proteins bind to this silencer fragment, one of which, designated SF-A (Silencer Factor A), has been partially purified. SF-A binds to several regions in this silencer, and likely plays an important role on negative regulation of this gene.

Effects of surface substances of untransformed fibroblastic cells on the adhesion and proliferation of neighboring cells: a study using fixed confluent cell sheets

To study the effects of surface materials of cells on the behavior of other neighboring cells in a crowded culture, confluent sheets of rat 3Y1 fibroblasts were fixed and then 3Y1 cells were seeded on to them. Among confluent sheets unfixed, fixed with formalin and fixed with ethanol and an empty plastic dish surface, the substrate activity to permit cell adhesion was compared. After confluent 3Y1 cells (mainly composed of cells with a G1-DNA content) were reseeded with fresh medium on to these substrates, the capacity to initiate DNA synthesis per attached cell was also compared. The substrate activity of the ethanol-fixed cell sheet to permit cell adhesion was as high as that of the empty dish surface, whereas that of the unfixed cell sheet and that of the formalin-fixed cell sheet were low. When the ethanol-fixed cell sheet and the empty dish surface were coated with the ethanol extract of the unfixed cell sheet, the substrate activity diminished, indicating that during the fixation process with ethanol an adhesion-inhibitory factor (s) was removed. The capacity to initiate DNA synthesis of each cell that had completed adhesion and spreading on the cell sheets unfixed, fixed with formalin, and fixed with ethanol was lower compared to the cell that had adhered to the empty dish surface. We conclude that factors over the 3Y1 cell surface inhibit the overlapping cell adhesion and the proliferation of cells contacting each other, resulting in the ordered cell configuration in the confluent culture.

Contribution of growth factors to heat production by cultured rat fibroblasts

The heat released from rat 3Y1 fibroblasts was measured by the stopped-flow method using a flow microcalorimeter. The heat output from a monolayer culture is defined as the maximum heat output from the cell suspension, after dispersion of the monolayer. The heat output per cell was not significantly changed when exponentially proliferating cells ceased dividing, with a G1 DNA content, at confluent cell density. When the growth-arrested (resting) cells were exposed to fresh medium containing various combinations of growth factors, heat output increased in parallel with the fraction of the cells that entered S phase of the cell cycle. The increase in heat output was correlated with the increase in cell volume. We infer from these findings that the resumption of cell proliferation stimulated by growth factors involves an increase in cell volume and a concomitant increase in heat production, but that entry into the resting state does not involve abrupt decreases in cell volume and heat production.

The yeast heat shock transcription factor contains a transcriptional activation domain whose activity is repressed under nonshock conditions

Transcription of heat shock genes is induced by exposure of cells to elevated temperatures or other stress conditions. In yeast, it is thought that induction of transcription is mediated by conversion of a DNA-bound transcriptionally inactive form of the heat shock transcription factor (HSTF) to a DNA-bound transcriptionally active form. We have identified domains in HSTF involved in transcriptional activation and in repression of transcriptional activation at non-shock temperatures. We present evidence that a temperature-regulated transcriptional activation domain exists in HSTF and that this domain is essential for survival of yeast cells at heat shock temperatures. We propose a model for temperature-regulated transcriptional activation by a derepression mechanism.

Transformation by v-H-ras does not restore proliferation of a set of temperature-sensitive cell-cycle mutants of rat 3Y1 fibroblasts

Three temperature-sensitive cell-cycle mutants of rat 3Y1 fibroblasts (3Y1tsD123, 3Y1tsG125, and 3Y1tsH203, each belonging to distinct complementation groups) were transformed with plasmid DNA carrying Harvey murine sarcoma virus cDNA. The criteria for transformation were increase in saturation cell density, capability to clone in soft agar, and alteration in the cellular morphology. At 39.8 degrees C (restrictive temperature of the parental cell lines), all the transformed sublines of each mutant ceased to proliferate and were arrested reversibly in the G1 phase of the cell cycle like the parental lines. At both 39.8 degrees C and 33.8 degrees C (permissive temperature for the parental lines), all the untransformed parental lines synthesized p21ras at low rate. At 33.8 degrees C, all the transformed sublines synthesized p21ras at much higher rate and expressed the morphological phenotype characteristic to v-H-ras-induced transformation. At 39.8 degrees C, the rate of p21ras synthesis was not changed in the transformed sublines of 3Y1tsD123 and 3Y1tsG125, and the morphology of transformed phenotype also remained intact. In the transformed subline of 3Y1tsH203, the rate of p21ras synthesis was lowered at 39.8 degrees C to that seen in the untransformed parental line, and the transformed phenotype in morphology disappeared. In all of the transformed sublines, the amount of v-H-ras mRNA markedly expressed at both 33.8 degrees C and 39.8 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

[Double chambered right ventricle: surgical experience in a 60-year-old woman]

The patients reported as double chambered right ventricle are mainly children. A 60-year-old woman had been pointed out for her systolic cardiac murmur without any symptom. She was admitted to our hospital for her gradual onset of fatigue, lassitude. Cardiac catheterization data revealed a 105 mmHg peak-to-peak gradient within the right ventricular cavity with normal pulmonary pressures [20/5 (12) mmHg]. Right ventricular end-diastolic pressure was 4 mmHg. Right ventriculogram demonstrated double chambered right ventricle. Electrocardiogram showed neither right ventricular hypertrophy nor upright T wave in V3R. In order to release intraventricular pressure gradient and her symptom, the anomalous muscle bundles were resected through both the right atrium and the pulmonary artery. Surgical repair without right ventriculotomy is suitable for such an elder patient with double chambered right ventricle whose ventricular function may decrease.

[Flow cytometric DNA analysis of papillary carcinoma of the thyroid using paraffin-embedded specimens]

A flow cytometric DNA analysis of papillary thyroid carcinomas has been performed on paraffin-embedded specimens, in order to determine the clinical usefulness of this method by defining the degree of the biological malignancy. Fifty-eight patients with papillary carcinomas were followed from 2 to 8 years. They were classified according to their prognosis into three groups: non-recurrent (47 patients), recurrent (5 patients), and a deceased group (6 patients). Aneuploidy was found in 6 (10.3%) of the total 58 patients. It was more frequently detected in the recurrent (40%) and in the deceased (33.3%) groups than in the non-recurrent group (4.3%). Higher proliferating index values were observed in the deceased group than in the recurrent and non-recurrent groups. These results indicate that a DNA analysis, using routine paraffin-embedded materials, is a useful adjunct in the determination of the degree of the biological malignancy of a papillary carcinoma.

Functional cooperativity between two TPA responsive elements in undifferentiated F9 embryonic stem cells

We have recently identified an enhancer, termed GPEI, in the 5'-flanking region of the rat glutathione transferase P gene, that is composed of two imperfect TPA (phorbol 12-O-tetradecanoate 13-acetate) responsive elements (TREs). Unlike other TRE-containing enhancers, GPEI exhibits a strong transcriptional enhancing activity in F9 embryonic stem cells. Mutational analyses have revealed that the high activity of GPEI is mediated by two imperfect TREs. Each TRE-like sequence has no activity by itself but acts synergistically to form a strong enhancer which is active even in the very low level of AP-1 activity in F9 cells. Furthermore, we show that synthetic DNAs containing two perfect TREs in certain arrangements have strong transcriptional enhancing activities in F9 cells and the activity is greatly influenced by the relative orientation and the distance of two TREs.

[Stratification of the experimental incipient caries (polarized light microscopy and microradiography)]

The enamel caries establishes when at least a part of enamel dissolves by the action of cariogenic bacteria which produce insoluble glucan and lactic acid. The experimental caries should be prepared at the condition which simulates the natural environment. The author made 1 mm thick sections from 29 teeth extracted for convenience of orthodontic reason. The surface was covered except the "window" which will be exposed to the acid milieu. The samples were immersed for 4 to 120 days in the gelatin added lactate buffer of pH 4.5, pH 5.0, and pH 5.5. Ground sections were made after the experiment. The structure of the experimental incipient caries was described after Darling (1963); surface layer, body of the lesion, dark zone, and translucent zone. When the section was immersed for shorter period in the buffer of pH 4.5, the lesion was made up only two layers, namely, the surface layer and the body of the lesion. This type of lesion will be called Type I, hereafter. When the action of acid was more intense, only one layer, the body of the lesion remained after the dissolution of the surface layer. This type of lesion will be called Type II. The lesion which provided with all 4 layers will be called as Type III, and the lesion which was made up of 3 layers which remained after dissolved surface layer, will be called as Type IV. Both Type III and Type IV were established after immersing for longer period in pH 5.5, although they could be observed in groups which immersed in lower pH. Of the samples examined, a few example showed a five-layered structure; the surface layer, the first body of lesion, the first dark zone, the second body of lesion, the second dark zone, and the translucent zone. This phenomenon suggests that the speed of caries development was not uniform throughout the experiment. The relationship between the depth of the lesion, and the pH and the duration of acid action was studied. In the pH 5.0 group, the development of caries lesion was temporarily arrested between 30 and 60 days. This phenomenon would be an explanation to the formation of five-layered lesion.

The effects of sodium fluoride on the resorptive activity of isolated osteoclasts

It is not clear to what extent the increased bone mass observed in vertebral trabecular bone of fluoride-treated mammals is a consequence of effects of fluoride on the number and activity of osteoclasts or of osteoblasts. In the present communication, we have analyzed the effects of NaF on the activity of isolated rabbit osteoclasts cultured on thin slices of devitalized compact bovine bone. Osteoclastic resorption was quantitated by counting the number of resorption lacunae and measuring their surface area and their depth using scanning electron microscopy. Our results show that NaF in concentrations of 0.5-1.0 mM decreased the number of resorption lacunae made by individual osteoclasts and decreased the resorbed area per osteoclast. We argue that the concentration of fluoride in these experiments may be within the range "seen" by osteoclasts in mammals treated for prolonged periods with approximately 1 mg of NaF/kg body weight (bw) per day.

A novel octamer binding transcription factor is differentially expressed in mouse embryonic cells

We have identified a novel octamer binding factor (Oct-3) in P19 embryonal carcinoma cells. Oct-3, which recognizes the typical octamer motif (ATTTGCAT) as well as the AT-rich sequence TTAAAATTCA, is present in P19 stem cells but disappears when the cells are induced to differentiate by retinoic acid (RA). Cloned cDNA corresponding to Oct-3 encodes a protein of 377 amino acids. Oct-3 has a conserved POU domain, but the remaining part is distinct from other POU domain-containing proteins such as Oct-1 and Oct-2. mRNA of 1.5 kb coding for Oct-3 is abundant in P19 stem cells but is dramatically repressed during RA-induced differentiation. Repression of the 1.5 kb mRNA is rapid and specific to RA. In mouse, oct-3 mRNA is undetectable in all the adult organs examined. The N-terminal proline-rich region of Oct-3, when fused to the DNA binding domain of c-Jun, functions as a transcriptional activating domain. We suggest that Oct-3 is a novel octamer binding transcription factor that is developmentally regulated during mouse embryogenesis.

Cell-cycle independent increase in heat production in response to growth factors in cultured rat fibroblasts: interpretation by continuum model

We measured the heat output from rat 3Y1 fibroblastic cells by stopped-flow method using a flow microcalorimeter. When the resting cells were stimulated to initiate DNA synthesis with growth factors, the heat output increased. Although cells normally progressed through S and G2 phases in the absence of any growth factor, cells increased the heat output in response to the growth factors during the progression through these phases. These results are consistent with the continuum model in which the preparation for the initiation of S phase occurs continuously and cumulatively between adjacent S phases not restricted in G1 phase.

Prostaglandin E2 initially inhibits and then stimulates bone resorption in isolated rabbit osteoclast cultures

Osteoclasts were isolated from the long bones of neonatal rabbits and cultured on devitalized bovine bone slices for 8, 24, 48 and 72 h with and without prostaglandin E2 (PGE2) (10(-6) M). The number of osteoclasts present at the end of the culture periods was counted after staining the cells for tartrate resistant acid phosphatase (TRAP). After removal of the cells, the resorption lacunae excavated by the osteoclasts were observed by scanning electron microscopy (SEM) and their size and depth calculated by computer-assisted morphometric and stereomorphometric techniques. PGE2 had no effect on the number of TRAP positive multinucleated osteoclasts, but decreased the number of TRAP positive mononuclear cells. The total area of the excavated pits and the area excavated per osteoclast in PGE2-treated cultures were decreased by 62 and 58% respectively after 8 h in culture. After 24 h in culture, the total excavated area and the excavated area per osteoclast were still 44 and 38% lower in the PGE2-treated cultures than in the corresponding control cultures. However, after 48 h of culture, resorptive activity in PGE2-treated cultures was consistently greater than in control cultures. In the course of a 48 h culture period, the PGE2 concentration decreased from 1.0 x 10(-6) to 0.3 x 10(-6) M. Thus, despite the continuous presence of PGE2, the resorptive activity of osteoclasts not only recovered from the transient inhibitory effect of PGE2, but was actually greater than in the control cultures. This confirms that the effects of PGE2 in isolated osteoclast preparations are inhibitory in short term cultures, but shows that the effects of PGE2 in such preparations are stimulatory in longer term cultures. Proliferating stromal cells with osteoblast-like characteristics comprised approximately 45% of the 'osteoclast' cultures at the start of the cultures, but their number increased to 93% of the total cell population at 48 h and to 98% at 72 h. Our results suggest that the PGE2-induced stimulation of osteoclastic activity represents an indirect effect mediated by stromal cells derived from bone marrow. Our results also indicate that the increased resorptive activity in PGE2 treated cultures can be accounted for by an increase in the size of the resorption lacunae and is not caused by an increase in osteoclast number.

Increase in c-fos and c-myc mRNA levels in untransformed and SV40-transformed 3Y1 fibroblasts after addition of serum: its relationship to the control of initiation of S phase

When rat 3Y1 fibroblasts were exposed to serum after 7.5 h of S, G2, and M phases in the absence of serum, the c-fos and c-myc mRNA levels markedly increased. This marked increase was also observed when density-arrested cells were stimulated with fresh serum to initiate proliferation. Increase in the c-fos and c-myc mRNA levels was not observed in cells that had traversed 7.5 h in these phases in the presence of serum. Cells passing through S, G2, and M phases in the absence of serum delayed entry into the next S phase approximately 8 h compared to control cells incubated in the presence of serum. Also, when density-arrested cells were stimulated with serum for 5 h, then deprived of serum for 8 h, and then incubated in serum again, the c-fos and c-myc mRNA levels increased. In this last case, the total excess time of serum exposure required to enter S phase was only 2 h, indicating that cells had not returned to the initial density-arrested state during the serum deprivation period. The increase in c-fos and c-myc mRNA levels following addition of serum after incubation in the absence of serum was also observed in SV40-transformed 3Y1 cells. The entry of SV40-transformed cells into S phase was not markedly affected by the absence of serum. These results can be explained by assuming that there is a process leading to the initiation of S phase that is operating or accumulating continuously in all cell cycle phases. In 3Y1 cells the expression of the c-fos and c-myc genes is required at any cell cycle phase, and the increase in c-fos and c-myc mRNA levels in response to changes in serum concentration simply reflects the possible overexpression due to the delay of a hypothesized negative feedback regulation. In SV40-transformed 3Y1 cells, the process leading to the initiation of S phase operates normally in response to growth factors, and the SV40 large T antigen supplements or enhances the process in the absence of the growth factors.

Proliferative behaviour of fibroblasts in plasma-rich culture medium

We examined the proliferative behaviour in tertiary culture cells of human skin fibroblasts (HSF) as well as cells of the rat 3Y1 diploid fibroblast line placed on a plastic substratum in a nutrient-rich medium containing high concentrations of platelet-poor plasma (PPP). Autochthonous human PPP was used for the HSF cells and heat-treated (at 56 degrees C for 30 min) bovine PPP was used for the 3Y1 cells. In both types of cells, the saturation cell density rose with increasing PPP concentration and reached a plateau at 30–90% PPP. When the cells were cultivated in serum, the saturation densities were the same as those with the same concentrations of corresponding PPP in both the HSF and 3Y1 cells. When the cells were arrested at a saturation cell density in a medium containing 10% PPP and then were refed with a fresh medium containing 90% PPP, DNA synthesis and cell division occurred in both types of fibroblasts. This effect was either reduced in the HSF cells or enhanced in the 3Y1 cells by the addition of platelet lysate. TGF-beta 1 added to the fresh medium containing 90% PPP also inhibited the induction of DNA synthesis in the HSF cells but not in the 3Y1 cells. The inhibitory effect of the platelet lysate was neutralized by anti-TGF-beta 1 IgG. On the other hand, PDGF added to the fresh medium had no effect on either type of cells. These results suggest that cultured fibroblasts are capable of proliferating on a plastic substratum under fluid conditions that essentially reflect the fluid environment of the body, as long as sufficient nutrients are supplied. Platelet lysate represses the proliferation of HSF cells, possibly through the inhibitory effect of TGF-beta 1, and promotes the proliferation of 3Y1 cells by growth factor(s) other than PDGF and TGF-beta 1.

Mechanism of selective killing by dilinoleoylglycerol of cells transformed by the E1A gene of adenovirus type 12

Rat 3Y1 fibroblasts transformed by the E1A gene of adenovirus type 12 (E1A-3Y1 cells) are highly sensitive to the cell-killing effect of 1,3-dilinoleoylglycerol (DLG) administered in a culture medium, whereas the parental 3Y1 cells are less sensitive (H. Shimura et al., Cancer Res., 48: 578-583, 1988). The selective cytotoxicity of DLG to E1A-3Y1 cells was markedly reduced by the simultaneous administration of nonspecific antioxidants such as vitamin E, butylated hydroxytoluene, and ascorbic acid. Specific scavengers for oxygen radicals had no effect. Lipoxygenase inhibitors (nordihydroguaiaretic acid, esculetin, and baicalein) reduced the DLG-mediated selective cytotoxicity, whereas cyclooxygenase inhibitors (acetylsalicylic acid and indomethacin) showed no effect. The intracellular and extracellular contents of the products from lipid peroxidation as measured by the thiobarbituric acid test were significantly greater in E1A-3Y1 cells than in the parental 3Y1 cells. In comparison with DLG, linoleic acid and monolinoleoylglycerol were equally toxic to E1A-3Y1 and parental 3Y1, and trilinoleoylglycerol was weakly toxic to both types of cells. Scanning electron microscopy revealed that numerous holes about 0.2 micron in diameter were scattered all over the surface of the E1A-3Y1 cells after treating the cultures with DLG. These results suggest that; (a) the DLG-mediated cytotoxicity to the E1A-transformed cells is attributable to lipid peroxidation; (b) the structural property of DLG is essential to the E1A specificity of cytotoxicity; and finally (c) the destruction of the cell membrane is the basis of cytotoxicity of DLG.

Structure and expression of the rat c-jun messenger RNA: tissue distribution and increase during chemical hepatocarcinogenesis

c-jun is the cellular homologue of the recently isolated nuclear oncogene v-jun. This protooncogene encodes the cellular transcription factor AP-1. We have isolated the complementary DNA clone of rat c-jun mRNA. The rat c-jun complementary DNA clone encodes 334 amino acid residues, the sequence of which shows about 98, 96, and 81% homologies with mouse, human, and chicken c-jun products, respectively. The c-jun mRNA is highly expressed in the lung and slightly expressed in the brain. The amount of mRNA is even smaller in the liver and is not detected in the spleen. We have also determined c-jun expression during chemical hepatocarcinogenesis and demonstrated increased expression of mRNA in the precancerous lesion, hyperplastic nodules, as well as in the primary hepatocellular carcinomas.

Structural and functional analysis of an enhancer GPEI having a phorbol 12-O-tetradecanoate 13-acetate responsive element-like sequence found in the rat glutathione transferase P gene

We have recently identified a typical enhancer, termed GPEI, located about 2.5 kilobases upstream from the transcription initiation site of the rat glutathione transferase P gene. Analyses of 5' and 3' deletion mutants revealed that the cis-acting sequence of GPEI contained the phorbol 12-O-tetradecanoate 13-acetate responsive element (TRE)-like sequence in it. For the maximal activity, however, GPEI required an adjacent upstream sequence of about 19 base pairs in addition to the TRE-like sequence. With the DNA binding gel-shift assay, we could detect protein(s) that specifically binds to the TRE-like sequence of GPEI fragment, which was possibly c-jun.c-fos complex or a similar protein complex. The sequence immediately upstream of the TRE-like sequence did not have any activity by itself, but augmented the latter activity by about 5-fold.

Expression of calcitonin receptors during osteoclast differentiation in mouse metatarsals

Metatarsal bones of 15-day-old mouse embryos contain proliferative tartrate-resistant acid phosphatase (TRAP) negative (-) osteoclast progenitors that progressively differentiate into multinucleated TRAP positive (+) osteoclasts. Using histochemical and autoradiographic techniques, we have examined the expression of calcitonin receptors during osteoclast differentiation in mouse metatarsals. Fresh mouse metatarsals from embryos aged 14-17 days and metatarsals from 15-day-old embryos cultured for 1, 2, 3, and 6 days were stained for TRAP. Calcitonin binding to osteoclasts and their precursors was studied by incubating metatarsals with [125I]salmon calcitonin (sCT) and quantitating grain counts from autoradiographs of tissue sections. Calcitonin receptors first appear on nonproliferating osteoclast precursors, most often just after or simultaneously with the development of TRAP activity. The effect of sCT on the development of TRAP+ mononuclear preosteoclasts was examined by culturing 15-day-old metatarsals in the continuous presence of 5 mU sCT for periods of up to 3 days and quantitating the number of TRAP+ mononuclear preosteoclasts that develop. Calcitonin did not affect the differentiation of osteoclasts up to the stage of the TRAP+ mononuclear preosteoclast.

[A simultaneous operation of A-C bypass and replacement of abdominal aortic aneurysm--a successful case]

A 70-year-old man was successfully operated on A-C bypass for coronary triple vessel disease and replacement of abdominal aortic aneurysm. The two different procedures were performed simultaneously under cardio-pulmonary bypass. This simultaneous operation can provide benefits of shortening operating time and of clamping easily the abdominal aorta.

Frequency of cell transformation by the small DNA tumor viruses: infection of proliferating cells and quiescent cells

Small DNA-containing tumor viruses (simian virus 40, mouse polyoma-virus, and adenoviruses) malignantly transform fibroblasts of the susceptible rodents. Fibroblasts can exist, in vitro and in vivo, in either of the two states: the proliferating state or the quiescent state. In the present study, we examined whether the state of fibroblasts at the time of exposure to these DNA viruses affects the frequency of transformation. Dense-focus formation in monolayer culture of rat 3Y1 fibroblasts was used to quantitate transformation. Results show that the frequency of transformation by simian virus 40 and mouse polyomavirus was reduced when cells were in the proliferating state at the time of virus inoculation as compared to cells in the quiescent state, whereas that by adenovirus type 12 was similar in the two cellular states. The reduction of the frequency of transformation in proliferating cells infected with simian virus 40 was also observed in BALB/c 3T3 mouse cells. Mechanisms underlying the difference between the two cellular states and the difference between the papovavirus and adenovirus in this aspect of transformation remain to be investigated.

Selective killing of transformed fibroblasts by combined treatment with cycloheximide and aphidicolin

The possibility of selective killing of transformed cells in a mixed population of untransformed and transformed cells was examined using a cell culture system of rat 3Y1 fibroblasts (parental 3Y1 cells, 3Y1 cells transformed with either SV40, polyoma virus, Rous avian sarcoma virus, E1A gene of adenovirus type 12, or H-v-ras oncogene). The principle of the selective killing is as follows. Under suboptimal culture conditions, untransformed cells are inhibited from progressing through G1 phase and retain viability, while transformed cells are not arrested. When DNA synthesis is inhibited for a long period, both types of cells in S phase die. Therefore, if we administer inhibitors of G1 progression and of DNA synthesis simultaneously to a cell population consisting of untransformed and transformed cells, most untransformed cells are arrested in G1 phase, retaining viability, while transformed cells leak from the G1 phase, cease DNA synthesis, and gradually die The present study shows that all types of transformants in stationary-phase cultures (consisting of cells mainly with a G1 DNA content) were killed to higher extents compared with untransformed cells, during incubation at lower cell densities with a combination of cycloheximide (G1 inhibitor) and aphidicolin (DNA-synthesis inhibitor). However, cycloheximide reduced the killing effect of aphidicolin by changing the irreversible DNA-synthesis inhibition to a reversible inhibition. The availability of G1 inhibitors that do not interfere with the irreversibility of inhibition of DNA synthesis is required for the treatment of cancer based on this idea.

Transient increase in the c-fos mRNA level after change of culture condition from serum absence to serum presence and after cycloheximide addition in rat 3Y1 fibroblasts

When 3Y1 cells resting at a saturation density were mitotically stimulated with serum, the c-fos mRNA level markedly increased in a short period of time and then decreased rapidly to an undetectable level. Subsequent serum deprivation followed by serum re-addition or subsequent cycloheximide addition caused a transient re-increase in the c-fos mRNA level. These results can be explained by assuming that the continuous expression of the c-fos gene at a minimum level is necessary for the eventual initiation of S phase, and that the over-expression of the c-fos gene occurs when the control of the gene expression is transiently disturbed by the change of the culture condition.

Metabolic responses of chicken embryos to graded, prolonged alterations in ambient temperature

1. Chicken embryos aged 12, 16, 18 and 20 (externally pipped) days of incubation were exposed to graded reductions (2 degrees C) in ambient temperature from 38 to 28 degrees C, exposure to each temperature lasting up to 9 hr. 2. Oxygen uptake was measured first at 38 degrees C and then in the quasi-equilibrium state at lowered temperatures. The temperature coefficient (Q10) was calculated for each egg. 3. For mild cooling (32 degrees C), the Q10 in 18-day-old embryos was about 1.5, while 12- and 16-day-old embryos had a Q10 value of about 2, indicating that a feeble homeothermic metabolic response to cooling appears in late prenatal embryos. It became more marked in externally pipped embryos and further augmented in hatchlings.

Multiple regulatory elements and phorbol 12-O-tetradecanoate 13-acetate responsiveness of the rat placental glutathione transferase gene

We have analyzed the cis-acting regulatory DNA elements of the placental rat glutathione S-alkyltransferase (GST-P) gene. Various regions of the 5' flanking sequence were fused with a bacterial chloramphenicol acetyltransferase gene. The transcriptional activity of each construct was determined by the transient expression assay after introduction into a hepatoma cell line. Multiple regulatory elements were identified. Two enhancing elements were located 2.5 and 2.2 kilobases upstream from the transcription start site and designated GST-P enhancers I and II (GPEI and GPEII, respectively). A consensus sequence of the phorbol 12-O-tetradecanoate 13-acetate responsive elements was present in the GPEI and at position -61. GPEII contained two of the simian virus 40 and one of the polyoma enhancer core-like sequences. A silencing element was also found 400 base pairs upstream from the cap site. In accordance with the above observation, endogenous GST-P gene was found to be stimulated when the rat fibroblast line 3Y1 was treated with phorbol 12-O-tetradecanoate 13-acetate. Phorbol 12-O-tetradecanoate 13-acetate enhanced the expression of the transfected GST-P gene to a much higher degree in HeLa cells than in the hepatoma cells, which constitutively expressed the endogenous GST-P. The results are discussed in terms of the specific derepression of GST-P gene during hepatocarcinogenesis in the rat.

Short-term effects of altered shell conductance on oxygen uptake and hematological variables of late chicken embryos

The preceding report on the O2 uptake (MO2) of chicken embryos whose shell conductance (GO2) was altered from the beginning of incubation showed that the MO2 was decreased despite increased GO2 [Okuda, A. and H. Tazawa (1988) Respir. Physiol. 74: 187-198]. This was attributed to an excess water loss which reduced the growth of the embryos. The present study was designed to investigate the short-term effects of altered GO2, obviating the effect of excess water loss, on the MO2 and simultaneously on the hematological variables of embryos on days 16-17 and days 18-19 of incubation. The MO2 measured 5 h after increasing the GO2 was neither decreased nor increased significantly. The diffusing capacity of the chorio-allantoic membrane, which was estimated using the Bohr integration procedure, decreased as the GO2 was increased. When the GO2 was decreased, on the other hand, the decrease in MO2 was not so large as expected from the decrease in GO2, for both 16- and 18-day-old embryos. The effect of reduced GO2 on MO2 was more prominent in 18-day-old embryos than 16-day-old embryos. One-day-long hypoxia due to decreased GO2 induced erythropoiesis in 18-19-day embryos, but did not do so in 16-17-day embryos. The increase in hematocrit value of the latter group of embryos was attributed to an increase in cell volume due to concurrent hypercapnia.

Gas exchange and development of chicken embryos with widely altered shell conductance from the beginning of incubation

The O2 uptake of chicken embryos confined in the eggshell (MO2) is governed by a shell diffusive conductance (GO2) and PO2 difference between ambience and air space, suggesting that a relation between GO2 and air space PO2 (PAO2) is hyperbolic at constant MO2. Upon wide alteration of GO2 from the beginning of incubation, the MO2 was measured on day 16 of incubation and the relation between GO2 and PAO2 examined. The MO2 increased hyperbolically with increasing GO2, reached maximum at control conductances and decreased with further increase in GO2. From these changes in MO2 with GO2, an equation was derived predicting PAO2 as a quadratic function of inverse gO2 (mass-specific conductance, i.e., GO2 standardized by fresh egg mass), and the relation between air space PO2 and shell conductance was no longer hyperbolic. The arterialized blood PO2 (PaO2) of the allantoic vein measured individually was also expressed by a quadratic equation of inverse gO2. While for widely altered conductance the MO2 was little related to PaO2, the mass (embryo)-specific O2 uptake increased with PaO2. The excess water loss associated with increased conductance was involved in changes in these variables.

Non-specific elongation of cell cycle phases by cycloheximide in rat 3Y1 cells, and specific reduction of G1 phase elongation by simian virus 40 large T antigen

Partial inhibition of protein synthesis by cycloheximide caused prolongation of G1, S and G2 phases in rat 3Y1 fibroblasts. In cells expressing simian virus 40 (SV40) large T antigen, by infection with SV40 in the previous generation, the prolongation of G1 phase in the presence of cycloheximide was suppressed. However, the prolongation of S and G2 phases in the presence of cycloheximide was not suppressed in cells expressing large T antigen, by infection with SV40 in the current generation. Similarly, when density-arrested cells (cells in G0 phase) were infected with SV40 (either wild-type strain or a mutant deleted in the unique coding region for small t antigen) and reseeded sparsely in the presence of cycloheximide, the cycloheximide-induced delay of entry into S phase was suppressed. In this case, the reduction in [35S]methionine incorporation, that in protein accumulation and that in cell volume increase, were not surmounted by SV40 infection. In T-antigen-negative cells, all the regions in G1 phase seemed to be sensitive to cycloheximide, i.e. they suffered elongation. These results suggest that, in comparison with cells that enter S phase by the action of growth factors, cells expressing large T antigen can enter S phase more efficiently through a quite different process.

Segmental autotransplantation of the pancreas after total pancreatectomy for advanced periampullary carcinoma--a case report

A case is reported here in which segmental autotransplantation of the pancreas was performed after total pancreatectomy for advanced periampullary carcinoma in an attempt to preserve pancreatic endocrine function. The postoperative course was uneventful. The requirement of insulin decreased after the operation and the daily profile examination, done 5 months following surgery, showed a permissive fluctuation of blood sugar levels without insulin injection. Thus, segmental autotransplantation of the pancreas offers a method of preserving pancreatic endocrine function after total pancreatectomy for periampullary carcinoma in selected patients.

Elongation of G1 phase by transient exposure of rat 3Y1 fibroblasts to caffeine during the previous and present generations

When density-arrested rat 3Y1 fibroblasts were stimulated to enter S phase by seeding sparsely in fresh medium, caffeine inhibited this stimulation. When compared at the doses that gave the same levels of the inhibition of entry into S phase, caffeine inhibited protein synthesis to a far lesser extent than cycloheximide. This indicates that caffeine affects some event(s) specific to entry into S phase rather than general protein synthesis. When cells synchronized at early S phase were exposed to caffeine, progression of S and G2 phases was prolonged by only 1 h (from 6 h to 7 h). However, after removal of caffeine at mitosis, the G1 phase was prolonged for 5 h (from 11 h to 16 h). These results are consistent with our model that the initiation of S phase is regulated throughout the period between the adjacent S phases. When cells were incubated with normal medium containing serum during the S and G2 periods, a subsequent 6-h pulse exposure to caffeine caused prolongation of G1 phase for 7 h (from 11 h to 18 h). On the other hand, when cells were incubated in the absence of serum during these periods, the prolongation was only 2 h (from 16 h to 18 h). Similarly, entry into S phase was prolonged only 2 h, when a 6-h pulse exposure to caffeine was given immediately after release from density arrest or serum-deprivation arrest. These results indicate the involvement of the relaxation process, which is not affected by caffeine, when serum-deprived cells or density-arrested cells restore the process prerequisite for entry into S phase.

Factors affecting heat production of rat 3Y1 fibroblasts in flow microcalorimetry

Quiescent 3Y1 cells in monolayer cultures were dispersed with trypsin-EDTA, suspended in various media, and the cellular heat production was measured in a flow-type microcalorimeter set at 37 degrees C. A linear relationship was found to exist between the number of cells applied to the microcalorimeter and the heat output. Increasing concentrations of bovine serum albumin (BSA) and of fetal calf serum (FCS) added in Dulbecco's modified Eagle's medium (DEM) enhanced the heat output to the same saturation level. Trypsin inhibitor added in DEM enhanced the heat output, but to a lower saturation level than FCS or BSA did, indicating that BSA has an activity to enhance cellular heat production by a mechanism other than neutralizing residual trypsin. The heat output was found to gradually decrease in the microcalorimeter. This reduction was not enhanced by a two-fold dilution of the medium (DEM plus FCS) with phosphate-buffered saline, indicating that this reduction is not caused by the depletion of nutrients and serum factors in the medium. Similarly, when cells were incubated for 155 or 220 min in suspension in DEM plus BSA at 37 degrees C and applied to the microcalorimeter, the heat output decreased. However, no significant reduction of the heat output was observed after holding the cells at 0 degree C in suspension for the same period. This and other facts suggest that depletion of O2 dissolved in the medium is involved in the gradual decrease in heat output.(ABSTRACT TRUNCATED AT 250 WORDS)

Pancreatoduodenectomy for periampullary cancer associated with celiac occlusion: a case report

A 62-year-old man with atherosclerotic occlusion of the celiac axis underwent pancreatoduodenectomy because of cancer of the common bile duct. Preoperative angiography showed that the arterial blood supply to the celiac viscera was sustained through the gastroduodenal artery via the pancreaticoduodenal arcades from the superior mesenteric artery. Therefore reconstruction of the celiac circulation was attempted before division of the gastroduodenal artery. An autograft of the saphenous vein was placed between the infrarenal aorta and the common hepatic artery. The postoperative course was uneventful. Patency of the graft was demonstrated angiographically on the 50th postoperative day.