Responses of brown adipose tissue activity to unloading in rats

To study the responses of thermogenic activity in brown adipose tissue (BAT) to unloading, male Wistar rats were hindlimb suspended for 10 days. Compared with control rats, a significant increase in the BAT-to-body mass ratio and considerable differences in chemical components in BAT were observed in the hindlimb-suspended rats. These findings indicate a marked increase in the thermogenic capacity in BAT of the experimental group. Likewise, the thermogenic activity (which was assessed by guanosine 5'-diphosphate binding to BAT mitochondria) was markedly greater in the mitochondria recovered from BAT of the hindlimb-suspended rats than in those from the control rats (1,610 +/- 450 vs. 202 +/- 132 pmol recovered). Moreover, the uncoupling protein content in the BAT mitochondrial fraction of the hindlimb-suspended rats was significantly higher (1.6-fold) than that in the control rats. As was expected, the uncoupling protein mRNA expression was greater in hindlimb-suspended rats than in control animals. These results suggest that chronic hindlimb suspension leads to an increase in both the thermogenic capacity and the activity in BAT of rats.

Metal oxidoreduction by microbial cells

For many organisms, some heavy metals in external media are essential at low concentrations but are toxic at high concentrations. Strongly toxic heavy metals are toxic even at low concentrations. Recently, it was proven that changes of valencies of Fe, Cu and Mn were necessary for these metals to be utilized by organisms, especially microorganism. The valencies of Hg and Cr are changed by reducing systems of cells in the process of detoxifying them. Thus, the processes of oxidoreduction of these metals are important for biological systems of metal-autoregulation and metal-mediated regulation. Metal ion-specific reducing enzyme systems function in the cell surface layer of microorganisms. These enzymes require NADH or NADPH as an electron donor and FMN or FAD as an electron carrier component. Electron transport may be operated by transplamsa-membrane redox systems. Metal ion reductases are also found in the cytoplasm. The affinities of metal ions to ligand residues change with the valence of the metal elements and mutual interactions of various metal ions are important for regulation of oxidoreduction states. Microorganisms can utilize essential metal elements and detoxify excess metals by respective reducing enzyme systems and by regulating movement of heavy metal ions.

Changes of contractile properties of extensor digitorum longus in response to creatine-analogue administration and/or hindlimb suspension in rats

Changes of contractile properties of extensor digitorum longus in response to hindlimb suspension and/or altered high-energy phosphate contents were studied in rats. A reduction of high-energy phosphates, especially phosphocreatine, was seen in rats fed creatine analogue beta-guanidinopropionic acid (beta-GPA), but they were elevated after 10-d supplementation of creatine. The one-half relaxation time was increased by feeding beta-GPA, but was normalized by creatine supply. The fatigue resistance of creatine-depleted muscle was significantly improved, but tended to decrease by suspension and creatine supply, although it was still better than that in the control diet group. It is indicated that the contractile properties of muscle are influenced by the high-energy phosphate content. It is also suggested that the endurance capacity may be influenced by the mitochondrial respiratory capacity, but not necessarily by the levels of high-energy phosphates.

Metabolic adaptation of skeletal muscles to gravitational unloading

Responses of high-energy phosphates and metabolic properties to hindlimb suspension were studied in adult rats. The relative content of phosphocreatine (PCr) in the calf muscles was significantly higher in rats suspended for 10 days than in age-matched cage controls. The Pi/PCr ratio, where Pi is inorganic phosphate, in suspended muscles was less than controls. The absolute weights of soleus and medial gastrocnemius (MG) were approximately 40% less than controls. Although the % fiber distribution in MG was unchanged, the % slow fibers decreased and the % fibers which were classified as both slow and fast was increased in soleus. The activities (per unit weight or protein) of succinate dehydrogenase and lactate dehydrogenase in soleus were unchanged but those of cytochrome oxidase, beta-hydroxyacyl CoA dehydrogenase, and citrate synthase were decreased following unloading. None of these enzyme activities in MG changed. However, the total levels of all enzymes in whole muscles decreased by suspension. It is suggested that shift of slow muscle toward fast type by unloading is associated with a decrease in mitochondrial biogenesis. Further, gravitational unloading affected the levels of muscle proteins differently even in the same mitochondrial enzymes.

Responses of beta-adrenoceptor in rat soleus to phosphorus compound levels and/or unloading

Responses of beta-adrenoceptor (beta-AR) in rat soleus to gravitational unloading and/or changes in the levels of phosphorus compounds by feeding either creatine or its analogue beta-guanidinopropionic acid (beta-GPA) were studied. A decrease in the density of beta-AR (about -35%) was induced by 10 days of hindlimb suspension, but the affinity of the receptor was unaffected. Suspension unloading tended to increase the levels of adenosine triphosphate and phosphocreatine and decrease inorganic phosphate. Even without unloading, the beta-AR density decreased after an oral creatine supplementation (about -20%), which also tended to elevate the high-energy phosphate levels in muscle. However, an elevation of beta-AR density was induced (about +36%) after chronic depletion of high-energy phosphates by feeding beta-GPA (about +125%). Data suggest that the density of beta-AR in muscle is elevated if the high-energy phosphate contents are chronically decreased and vice versa. However, it may not be directly related to the degree of muscle contractile activity.

A variant mRNA species encoding a truncated form of Fas antigen in the rat liver

A variant form of the Fas antigen cDNA was isolated from the rat liver. The cDNA contains an insertion sequence of 25 nucleotide residues and codes for a protein consisting of 65 amino acids representing a signal peptide and an N-terminal portion of the extracytoplasmic domain of Fas antigen. The expression of a variant mRNA species is less abundant in the liver compared with that of an ordinary mRNA species. The variant mRNA, though its function is unknown, is plausibly produced by an alternative splicing.

Effects of vesnarinone (OPC-8212) on Ca(2+)-activated K channels and cytosolic Ca2+ in cultured smooth muscle cells from porcine coronary artery

Vesnarinone is a new, non vasodilating cardiotonic agent. This study compared the effects of vesnarinone and amrinone, a phosphodiesterase (PDE) inhibitors with vasodilating actions, on cultured smooth muscle cells from the porcine coronary artery. Application of vesnarinone (10(-4) M) or amrinone (10(-4) M) to the bath solution in cell-attached patches activated the KCa channel having a conductance of 133 pS (bath 2.7 mM K, pipette 140 mM K). Application of vesnarinone to the cytosolic side had no direct effect on KCa channel activities in inside-out patches. Activation of the KCa channel was suppressed when the intracellular production of cAMP was suppressed by preincubation with carbachol (10(-6) M). Amrinone, but not vesnarinone, lowered [Ca2+]i in the K(+)-depolarized smooth muscle cells (K+ = 70 mM). These results suggest that vesnarinone exerts an additional effect on [Ca2+]i that is independent of PDE inhibition. The difference in the effects on [Ca2+]i in vascular smooth muscle cells may explain in part the differing actions of these agents on vascular relaxation.

Responses of contractile properties in rat soleus to high-energy phosphates and/or unloading

Responses of contractile properties of soleus to unloading and/or changes in high-energy phosphate contents were studied in rats. Reduction of high-energy phosphates, especially phosphocreatine, in ankle extensors was induced by feeding beta-guanidinopropionic acid (beta-GPA). The major finding in the study was that the fatigability and speed-related contractile properties responded to unloading and creatine supplementation in a similar manner. The high-energy phosphate contents tended to be elevated after 10-d supplementation of creatine and hindlimb suspension. The shift toward slow-type, mainly due to an increased one-half relaxation time, was seen in rats fed beta-GPA. Such a shift was reversed by feeding creatine or by hindlimb suspension; however, the suspension-induced shift of contractile properties toward fast-type was not prevented completely by beta-GPA feeding. Although the muscle fatigue resistance did not change by beta-GPA feeding alone, the decrease in fatigue resistance following suspension and creatine supply was less in the beta-GPA group. It is suggested that the levels of high-energy phosphates and tension production play important roles in the regulation of contractile properties of the soleus muscle.

Non-insulin and non-exercise related increase of glucose utilization in rats and mice

The effects of high-energy phosphate contents in muscles on glucose tolerance and glucose uptake into tissues were studied in rats and mice. Enhanced glucose tolerance associated with depleted high-energy phosphates and elevated glycogen content in muscles and liver was observed in animals fed creatine analogue beta-guanidinopropionic acid (beta-GPA). Distribution of infused 2-[1-14C]deoxy-D-glucose in tissues especially in the soleus muscle, kidney, and brain was greater in mice fed beta-GPA than controls. The glucose uptake was decreased when the contents of ATP and glycogen were normalized following creatine supplementation. Plasma insulin in animals at rest was lower and its concentration after intraperitoneal glucose infusion tended to be less in animals fed beta-GPA than controls (p > 0.05), although the pattern of insulin response to glucose loading was similar to the control. The daily voluntary activity in beta-GPA fed mice was also less than controls. These results suggest that improved glucose tolerance is not related to elevated insulin concentration and/or decreased glycogen following exercise. Such improvement may be due to an increased mitochondrial energy metabolism caused by depletion of high-energy phosphates.

Regulation of hsp70 induction in thermotolerant HeLa cells

Upon exposure to heat shock, non-thermotolerant (NT) HeLa cells transiently synthesize a large amount of 70-kDa heat-shock protein (hsp70), whereas thermotolerant (TT) cells synthesize a small amount of hsp70. When the hsp70 mRNA of HeLa cells was analyzed, it became apparent that hsp70 mRNA in TT cells did not increase following heat shock, whereas hsp70 mRNA in NT cells did increase dramatically. A further analysis of the activation of the heat-shock transcription factor (HSF) showed that significant activation of HSF was observed immediately after heat shock in both NT and TT cells. However, activated HSF was rapidly repressed in the TT cells, but not in the NT cells. Thus, the decreased induction of hsp70 synthesis observed in the TT HeLa cells may be due to the immediate repression of activated cellular HSF, which probably results in the reduced induction of hsp70 mRNA. The hsp70 content in the TT cells was usually higher than in the NT cells. However, after heat-shock treatment, the hsp70 content of the NT cells increased to nearly the level of the TT cells concomitant with the repression of hsp70 synthesis. The association of activated HSF with hsp70 was observed in both NT and TT cells, and the amount of HSF-hsp70 complex within the cell increased in proportion to the increase in hsp70 in the cells. These findings strongly suggest that the activity of HSF is negatively regulated by the intracellular content of hsp70 in these cells. Furthermore, in vitro experiments on the activation of HSF suggest that HSFs of NT and TT cells may have different properties, or an unknown factor may exist which regulates HSF activation in these cells.

Regulation of hsp70 synthesis induced by cupric sulfate and zinc sulfate in thermotolerant HeLa cells

Upon exposure to the heavy metals copper and zinc, a large amount of 70,000-Da heat shock protein (hsp70) was synthesized in normal, non-thermotolerant (NT) HeLa cells, whereas only a little increase of hsp70 synthesis was observed in thermotolerant (TT) cells. To determine the inhibition mechanism of hsp70 induction in the TT cells, we first analyzed the hsp70 mRNA of these cells. Hsp70 mRNA in the NT cells increased immediately after exposure to these metals. In TT cells, however, the increase of hsp70 mRNA was delayed, even though it eventually increased to a similar or slightly lower level compared with NT cells. Further analysis of the activation of heat shock transcription factor (HSF) showed that a significant activation of HSF was observed immediately after exposure to these metals in the NT cells, whereas the activation of HSF was initially repressed in the TT cells. Thus, the decreased induction of hsp70 synthesis observed in the TT cells seemed to be due to the reduced translation of hsp70 mRNA and also in part to the reduced activation of HSF. Furthermore, by the gel mobility shift assay using anti-hsp70 antibody, the association of copper- and zinc-activated HSF with hsp70 was observed in both NT and TT cells. The amount of HSF-hsp70 complex was prominent in TT cells, in which the hsp70 content was 5 to 10 times higher than that in the NT cells. These findings strongly suggest that the activity of HSF is negatively regulated by hsp70 in the TT cells.

Production of phytochelatins in Polygonum cuspidatum on exposure to copper but not to zinc

We studied cellular resistance to copper of plant cells Polygonum cuspidatum. When callus of P. cuspidatum was incubated on medium containing 100 microM cupric sulfate, the callus grew as well as the control callus did. The copper content of the callus, however, was elevated to a similar level of the medium. When cell extracts of callus exposed to 100 microM cupric sulfate were fractionated by gel filtration chromatography, a specific copper peak was eluted at the region of molecular weights between 4000 and 1000. Since an appearance of the copper-containing materials was inhibited by buthionine sulfoximine and the partially purified copper-containing materials contained only three amino acids: glutamic acid, glycine and cystine, the materials were supposed to be gamma-glutamyl peptides phytochelatins. Callus of P. cuspidatum synthesized phytochelatins from 50 microM cupric sulfate and maximally at 100-150 microM cupric sulfate. When induction of phytochelatins by another heavy metal, zinc, was analyzed, the callus, however, did not synthesize phytochelatins on exposure to zinc sulfate up to 1 mM. These findings suggested that phytochelatins were required for resistance to copper but probably not to zinc in the plant cells.

Single moving dipole obtained from magnetic field of the heart in patients with left ventricular hypertrophy

Magnetocardiograms (MCGs) were recorded by means of a second-derivative SQUID (superconducting quantum interference device) magnetometer in 20 normal subjects and 28 patients with left ventricular overload to analyze the activation sequence of the heart and amplitude of estimated current source. In the normal subjects, the dipole was directed to the left and gradually superiorly 40 ms after the beginning of the QRS wave mainly due to the activation of the left ventricle. In the patients with hypertension, the direction and location of the dipoles were similar to those of the normal subjects, but their dipole moments were increased. In the patients with mitral regurgitation, the dipoles of late QRS were directed more inferiorly than in the normal subjects and their amplitude was increased. In the patients with aortic valve disease, the amplitude of the dipoles was increased markedly and their location was deviated more to the left than the dipoles of the normal subjects. We established the criterion for diagnosis of LVO from the dipole moment of 50 ms of 3.13 x 10(-3) A or more. The sensitivity of this criterion is significantly higher in the diagnosis of left ventricular overload than the electrocardiogram (ECG). The present study shows that the moving dipole method is useful to determine the increased electromotive force in patients with left ventricular overload and that sensitivity in diagnosis of left ventricular overload is increased.

Vasopressin modulates K(+)-channel activities of cultured smooth muscle cells from porcine coronary artery

The ATP-sensitive K+ channel (KATP channel) and the Ca(2+)-activated K+ channel (KCa channel) were active in cell-attached and excised inside-out patch configurations in cultured smooth muscle cells of the porcine coronary artery. Vasopressin activated the KCa channel (240 pS) when it was applied in the bath in the cell-attached patch mode presumably because of an increase in intracellular Ca2+, but it had no direct effect on the KCa channel. However, vasopressin directly blocked the KATP channel from outside the cell membranes in a concentration-dependent manner in both outside-out and cell-attached patch configurations; the K(+)-channel opener, nicorandil, reversed this effect. The KATP channel (30 pS) was highly active in the intact cell-attached patch configuration when the pipette contained a physiological concentration of Ca2+, suggesting that this channel may control the resting membrane potential. (The block might produce depolarization of the cells and might result in the contraction of smooth muscle cells.) These observations suggest that the KATP channel may play a role, at least in part, in controlling the contraction of smooth muscle cells of the coronary artery and that the control of vascular tone by vasopressin may be related to its ability to block the KATP channel.

Effects of culture temperature on the expression of heat-shock proteins in murine ts85 cells

The murine temperature-sensitive cell-cycle mutant, ts85, shows an abnormal induction of heat-shock proteins which is different from the wild type FM3A cells. This paper explores the effect of culture temperature on the expression of heat shock proteins in ts85 cells. When ts85 cells were maintained at 33 or 37 degrees C, these cells synthesized heat-shock protein (hsp) 70 following continuous heating at 39 degrees C or subsequent incubation after heating at 42 degrees C for 15 min. In contrast, these conditions are not conducive for hsp70 synthesis by FM3A cells. Moreover, ts85 cells which were maintained at 37 degrees C synthesized hsp70 following continuous heating at 42 degrees C or subsequent incubation after heating at 45 degrees C for 15 min. The synthesis of hsp70 in these cells corresponded to an increased level of hsp70 mRNA. Furthermore, the constitutive hsp105 level of cells maintained at 33 degrees C was only half of that of cells which were maintained at 37 degrees C, and cells maintained at 33 degrees C were more sensitive to subsequent heat treatment than those maintained at 37 degrees C. These results indicate that culture temperature not only affects the induction of hsp70 mRNA, but also cellular levels of hsp105 and the resulting thermal sensitivity of ts85 cells. These findings suggest that the other phenotypic characteristic of the mutant ts85 cells is also affected by culture temperature.

Characteristic induction of 70,000 da-heat shock protein and metallothionein by zinc in HeLa cells

The synthesis of a 70,000 dalton-heat shock protein (hsp70) is one of several heat shock proteins induced in HeLa cells during the incubation in medium containing zinc sulphate. The synthesis of hsp70 was increased in the presence of 200 microM zinc sulphate and above, but not at 100 microM zinc sulphate. On the other hand, the synthesis of metallothionein was activated in the presence of 100 microM zinc sulphate and above. Uptake of zinc into the cells depended on the concentration of zinc sulphate in the medium. The separation of intracellular zinc into three fractions by gel filtration chromatography; high molecular, metallothionein, and low molecular fractions, showed that zinc in the low molecular weight and metallothionein fractions was elevated in the presence of 100 microM zinc sulphate in the medium, whereas increase in the zinc content of the high molecular weight fraction occurred at 200 microM zinc sulphate and above. Inhibition of cell growth and cellular protein synthesis was also observed at 200 microM zinc sulphate and above, but not at 100 microM. From these findings, since the induction of hsp70 synthesis and inhibition of cell growth occurred concomitantly with the increase of zinc in the high and low molecular weight fractions, hsp70 seemed not to function in the detoxification of zinc, but it may participate in the repair of zinc-induced damage.

Effects of low culture temperature on the induction of hsp70 mRNA and the accumulation of hsp70 and hsp105 in mouse FM3A cells

We have shown that heat shock does not induce the synthesis of hsp70 in FM3A cells maintained at a low culture temperature of 33 degrees C although it does so in cells maintained at 37 degrees C [T. Hatayama et al. (1991) Biochem. Int. 24, 467-474]. In this paper, we show that FM3A cells maintained at 37 degrees C produced hsp70 mRNA during continuous heating at 42 degrees C or during postincubation at either 37 or 33 degrees C after being heated at 45 degrees C for 15 min, whereas cells maintained at 33 degrees C did not produce hsp70 mRNA during continuous heating at 37, 39, 42, or 45 degrees C, or during postincubation after being heated at any temperature. Thus the lack of hsp70 synthesis in cells maintained at 33 degrees C seemed to be due to the absence of hsp70 mRNA induction. Also, hsp70 was accumulated in cells maintained at 37 degrees C during continuous heating at 42 degrees C and during postincubation at 37 degrees C after heat shock at 45 degrees C, but not during postincubation at 33 degrees C. The cellular level of the constitutive hsp73 as well as the mRNA level were both similar in cells maintained at 33 and 37 degrees C. On the other hand, the cellular level of the constitutive hsp105 in cells maintained at 33 degrees C was only half of that in cells maintained at 37 degrees C. These hsp105 levels increased significantly in both types of cells after continuous heating at 39 degrees C. These findings indicate that the culture temperature affects not only the induction of hsp70 mRNA but also the accumulation of hsp70 and hsp105 in the cells.

Endothelin blocks ATP-sensitive K+ channels and depolarizes smooth muscle cells of porcine coronary artery

ATP-sensitive K+ channels with a conductance of 30 pS in smooth muscle cells of porcine coronary artery were found to be highly active in the intact cell-attached patch configuration when the pipette contained a physiological concentration of Ca2+ (greater than 10(-4) M). In the inside-out configuration, these channels were activated by extracellular Ca2+ and blocked by cytosolic ATP and glibenclamide. Endothelin applied to the pipette specifically blocked these channels in a concentration-dependent manner in the cell-attached configuration (half-maximal inhibition, 1.3 x 10(-9) M). A K+ channel opener, nicorandil, activated these channels even in the presence of 10(-8) M endothelin. In the whole-cell current-clamp method, the cell membrane was depolarized by endothelin and then repolarized by nicorandil. The membrane depolarization is closely related to contraction of smooth muscle cells. These results suggest that the ATP-sensitive K+ channels are important in controlling the vascular tone of the coronary artery and that endothelin can increase vascular tone by blocking these channels.

Characteristic synthesis and redistribution of 70 kd heat shock protein in thermotolerant Chinese hamster V79 cells

Upon exposure to heat shock the increased rate of hsp70 synthesis decreased more rapidly in thermotolerant V79 cells than in the non-thermotolerant cells. However, the levels of hsp70 in the thermotolerant cells at 12 h after a heat shock were almost the same as those in the non-thermotolerant cells. On the other hand, the migration of hsp70 from cytoplasm to nucleoli after a heat shock was very rapid in both thermotolerant and non-thermotolerant cells, but hsp70 in the nucleoli disappeared faster in the thermotolerant cells than in the non-thermotolerant cells, and this coincided with the faster decline of hsp70 synthesis in the thermotolerant cells. For the characteristic distribution of hsp70, protein synthesis was not required. Furthermore, the induction and expression of thermotolerance by the cells were little affected by the inhibition of protein synthesis. Thus, the synthesis of hsp70 itself seemed not to be essential for the induction and expression of thermotolerance of the cells, although hsp70 may be essential for thermoresistance of cells. The rapid decrease of hsp70 synthesis and the rapid disappearance of hsp70 from the nucleoli after a heat shock may be essential for the expression of thermotolerance of the cells.

Long-term histologic follow-up study of alcoholic liver disease

Forty Japanese patients with alcoholic liver disease (nonspecific change, 9; fatty liver, 5; hepatic fibrosis, 4; chronic hepatitis, 12; alcoholic hepatitis, 5; liver cirrhosis, 5) were followed for 3-17 yr (average 8 yr) with repeated liver biopsies (2-5 times; average 2.5 times) at intervals of more than 3 yr. All of the patients continued to consume alcohol during this observation period. Five out of 12 patients with chronic hepatitis and 2 of 5 patients with alcoholic hepatitis eventually progressed to cirrhosis, while none of the 4 patients with hepatic fibrosis became cirrhotic. Anti-hepatitis C virus antibody was positive in 2 patients with liver cirrhosis among 12 patients whose sera were available. Two patients with cirrhosis died of hepatic failure and one patient died of hepatocellular carcinoma. These data suggest that the long-term prognosis of alcoholic liver disease is not necessarily poor, but patients with chronic hepatitis or alcoholic hepatitis can be at risk of progression to cirrhosis.

Different induction of 70,000-Da heat shock protein and metallothionein in HeLa cells by copper

To clarify the physiological roles of heat shock proteins induced by copper, we studied the synthesis of these proteins and metallothionein, as well as the level and nature of copper incorporated into HeLa cells. Incubation in medium containing 200 microM cupric sulfate and above induced the synthesis of 70,000-Da heat shock protein (hsp70) in these cells. However, the synthesis of hsp70 did not increase in the presence of less than 200 microM cupric sulfate. On the other hand, the synthesis of metallothionein increased due to 100 microM cupric sulfate. The uptake of copper into the cells depended on the cupric sulfate concentration in the medium. To analyze the nature of the intracellular copper, cell extracts were separated by gel filtration chromatography into three fractions: the high molecular weight, metallothionein, and low molecular weight fractions. No copper was found in the low molecular weight fraction of control cells, but appeared distinctly at 200 microM cupric sulfate and above. Copper in the high molecular weight fraction also began to increase at 200 microM cupric sulfate and above, whereas in the metallothionein fraction it began to increase even at 50 to 100 microM cupric sulfate. Furthermore, inhibition of cell growth was also observed at 200 microM cupric sulfate and above but not at 100 microM and below.(ABSTRACT TRUNCATED AT 250 WORDS)

Induction of heat shock protein and thermal sensitivity of mammalian cells maintained at low culture temperature

Effects of low culture temperature on the induction of heat shock proteins in FM3A cells by a heat shock and on the thermal sensitivity of the cells were examined. FM3A cells maintained at 33 degrees C could not induce hsp70 during continuous heating or after a short heat shock at either 39, 42, or 45 degrees C, although FM3A cells maintained at a normal culture temperature of 37 degrees C can induce the synthesis of hsp70. Furthermore, the cells maintained at 33 degrees C were more sensitive to the subsequent heat shock than the cells maintained at 37 degrees C. Thus, the culture temperature of the mammalian cells may be an important factor for the induction of hsp70, and hsp70 may play an important role to protect or repair the thermal damage of cells.

Mandibular alveolar ridge extension method using a surgical splint with porous hydroxyapatite (HAP) particles

The mandibular alveolar ridge extension method is a surgical technique to extend the alveolar ridge up to the required level. Using a surgical splint prepared to meet the clinical requirements establishes the desirable alveolar ridge extension with porous hydroxyapatite (HAP) particles. Before the operation, a working cast of the extremely resorpted mandibular alveolar ridge is remodeled into its desired shape with paraffin wax, and the extended surgical splint is cured by clear acrylic resin. After subperiosteal tunnel dissection, the surgical splint is fixed to the mandible with circummandibular ligatures; then the HAP particles are injected into the tunnel. After healing, a treatment denture is cured between the artificial dentition and the surgical splint with self curing resin. In this method, the HAP particles are injected into the subperiosteal tunnel that is created between the surface of alveolar bone and the periosteum covered by the surgical splint; the migration of HAP particles completes the extension of the alveoral ridge.

Role of heat-shock proteins in the induction of thermotolerance in Chinese hamster V79 cells by heat and chemical agents

To examine the involvement of heat shock proteins in the induction of thermotolerance in Chinese hamster V79 cells, thermotolerance was induced by heating of the cells at 42 degrees C for 4 h or at 44 degrees C for 20 min, or by treatment of the cells with 50 microM sodium arsenite for 3 h or 20 micrograms/ml puromycin for 4 h. Under unstressed conditions V79 cells synthesized constitutively three major heat-shock proteins, hsp70, hsp85 and hsp105. On exposure to conditions under which thermotolerance was induced, the synthesis of constitutive hsp70, hsp85 and hsp105 increased, but the inducible form of hsp70 was not synthesized, indicating that this inducible form was not necessary for the induction of thermotolerance. Although the amounts of heat-shock proteins synthesized in the cells that acquired thermotolerance were not always more than those synthesized constitutively in unstressed cells, the stressed cells synthesized heat-shock proteins (especially hsp70) preferentially over other proteins. As the level of hsp70 in the thermotolerant cells was almost the same as that in unstressed cells, the specific accumulation of hsp70 seemed not to be required for the acquisition of thermotolerance. From these findings it seemed likely that, for the induction of thermotolerance in V79 cells, hsp70 preferentially synthesized during or after the stress has an important function. Or the synthesis of heat shock proteins may not be important, and constitutively synthesized heat-shock proteins acquire a specific function during or after the stress.

Effects of nitroglycerin on ATP-induced Ca(++)-mobilization, Ca(++)-activated K channels and contraction of cultured smooth muscle cells of porcine coronary artery

Extracellular application of ATP transiently increases the cytosolic-free Ca++ concentration ([Ca++]i) in cultured smooth muscle cells of porcine coronary artery, and this activates large conductance Ca(++)-activated K (Kca) channels. In the present study effects of nitroglycerin (NG) and 4-aminopyridine (4-AP) on [Ca++]; and contraction were studied. 4-AP blocked Kca channels and enhanced the rise of [Ca++]i with oscillation, which led to contraction of the cells. NG activated the Kca channels of 300 picosiemens and inhibited 4-AP-induced contraction and oscillation of [Ca++]i. These results suggest that the vasorelaxant effect of NG involves hyperpolarization of the cell membrane by activating the Kca channels. NG also cause rapid decrease of [Ca++]i during the Ca(++)-mobilization by ATP in Ca-free solution. Similar effects were observed with cyclic GMP, suggesting that the effects of NG on the Kca channels and [Ca++]i were mediated by cyclic GMP.

[Effects of prophylactic intraportal chemotherapy on liver function, blood profile and survival in patients with colo-rectal cancer]

Postoperative intraportal anti-cancer chemotherapy was used for 51 patients with curatively resected colorectal cancer who were selected in the randomized controlled study to evaluate its inhibitory effect on liver metastasis from colo-rectal cancer. In cases of intraportal chemotherapy, 30 mg of Mitomycin-C (in 3 doses) and 5 mg/kg (B.W.)/day (1985-1986) or 3 mg/kg/day (1987-1988) of 5-FU was injected through the catheter inserted into the portal vein during postoperative 14 days. In cases of the control group (58 patients), the same doses of the drugs were injected into the peripheral vein during the same term. Six patients with recurrences were observed in the intraportal chemotherapy group, and 3 of them had liver metastases. In the control group, more liver metastases were observed (5 of 7 recurrences were liver metastases). Intraportally injected 5 mg/kg/day of 5-FU slightly disturbed the liver function. The averages of the serum GOT, GPT and gamma-GTP level of these cases were higher than those of the control cases. Three mg/kg/day of intraportally injected 5-FU had no influence on the liver function. There were no differences in the incidence of leukocytopenia or thrombocytopenia between the two groups.

Resected case of hepatocellular carcinoma associated with lupoid hepatitis

A 65 year old woman with lupoid hepatitis developed hepatocellular carcinoma which was diagnosed at an early stage. She had no history of blood transfusion and serum hepatitis B virus markers were negative. Prednisolone and 6-mercaptopurine were administered for the treatment of lupoid hepatitis. A hepatocellular carcinoma was detected by the elevation of serum alpha-fetoprotein and imaging studies. A tumour, 1.4 cm in diameter, was located in the lateral segment of the left hepatic lobe. It was resected by hepatic subsegmentectomy. Histological study showed a hepatocellular carcinoma of Edmondson type II against a background of posthepatitic cirrhosis. The patient was in good condition 2.5 years after the operation.

[Hepatic arterial chemotherapy combined with hyperthermia or arterial embolization in unresectable liver tumor]

Fifty-four patients with unresectable malignant liver tumors (14 of hepatocellular carcinoma, 40 of metastasis to the liver from gastric or colo-rectal cancer) were treated with intra-hepato-arterial (IHA) injections of cis-diamminedichloroplatinum (II) (CDDP) plus 5-fluorouracil (5-FU). In 32 of the patients, the liver tumors were detected synchronously with the diagnosis of the primary cancers, which were resected palliatively. Therapeutic schedules consisted of bolus injections of CDDP (50 mg/body/week) and 5-FU (250 mg/body/day) [Regimen I], and CDDP (50 mg/body/10-14 days) and 5-FU (100 mg/body/day) [Regimen II]. In 48 patients treated with IHA chemotherapy only, a partial response (PR) was obtained in 6 of 14 (43%) evaluable patients for Regimen I and in 11 of 30 (37%) patients for Regimen II. The dose-limiting factor for treatment with CDDP was bone marrow toxicity, but this toxicity was remarkably alleviated in Regimen II without any decrease in antitumor effectiveness. In 13 patients, other modalities, such as total-body hyperthermia (4 patients), radiofrequency capacitive local hyperthermia (5), and temporary arterial embolization (4), were combined with IHA chemotherapy. PR was obtained in 7 of 13 (54%) patients with the combined therapy. This combined therapy was efficacious in 7 patients in whom no desired results were obtained by IHA chemotherapy only. The survival rate was 50% at 12 months. IHA chemotherapy with CDDP plus 5-FU, especially when according to Regimen II, appears to be a strongly recommended strategy for treatment of unresected primary or metastatic liver tumor. Further, addition of the hyperthermia or the arterial embolization might enhance the antitumor effect of IHA chemotherapy.

Prophylactic therapy for peritoneal recurrence of gastric cancer by continuous hyperthermic peritoneal perfusion with mitomycin C

Continuous hyperthermic peritoneal perfusion (CHPP) with a solution that contains mitomycin C (CHPP-M) has been clinically introduced as a prophylactic treatment for peritoneal recurrence of gastric cancer with serosal invasion. Two studies, each with a treated and a control group, were performed. In the historical control study the postoperative 3-year survival rate of patients (73.7%) in the treated group (n = 38) was significantly higher than the survival rate (52.7%) of those in the control group (n = 55) (P less than 0.04). In the random control study the survival rate (83%) of patients in the treated group (n = 26) was also higher than that (67.3%) of those in the control group (n = 21) in the 30 months that followed gastric surgery. However, there was no significant difference. In the historical control study with respect to the postoperative complications, anastomotic leak was observed in 8.5% of patients who were given CHPP-M and 12.8% patients who did not have CHPP-M. In the random control study anastomotic leak was observed in 3.1% of patients who had CHPP-M and 7.1% of patients who did not have CHPP-M. The incidence of adhesive ileus in patients having CHPP-M did not increase in historical or random control groups. Postoperative prolonged intestinal paresis or chemical peritonitis were not induced by CHPP-M. These results indicate that CHPP-M is a simple, safe, and readily available prophylactic therapy for peritoneal recurrence that may follow gastric cancer surgery.

Prophylactic therapy for peritoneal recurrence of gastric cancer by continuous hyperthermic peritoneal perfusion with mitomycin C

Continuous hyperthermic peritoneal perfusion (CHPP) with a solution that contains mitomycin C (CHPP-M) has been clinically introduced as a prophylactic treatment for peritoneal recurrence of gastric cancer with serosal invasion. Two studies, each with a treated and a control group, were performed. In the historical control study the postoperative 3-year survival rate of patients (73.7%) in the treated group (n = 38) was significantly higher than the survival rate (52.7%) of those in the control group (n = 55) (P less than 0.04). In the random control study the survival rate (83%) of patients in the treated group (n = 26) was also higher than that (67.3%) of those in the control group (n = 21) in the 30 months that followed gastric surgery. However, there was no significant difference. In the historical control study with respect to the postoperative complications, anastomotic leak was observed in 8.5% of patients who were given CHPP-M and 12.8% patients who did not have CHPP-M. In the random control study anastomotic leak was observed in 3.1% of patients who had CHPP-M and 7.1% of patients who did not have CHPP-M. The incidence of adhesive ileus in patients having CHPP-M did not increase in historical or random control groups. Postoperative prolonged intestinal paresis or chemical peritonitis were not induced by CHPP-M. These results indicate that CHPP-M is a simple, safe, and readily available prophylactic therapy for peritoneal recurrence that may follow gastric cancer surgery.

[Intrahepatic-artery infusion of cis-diamminedichloroplatinum (II) and 5-fluorouracil in primary or metastatic liver cancer]

Eight hepatocellular cancer patients and eighteen metastatic liver cancer patients were treated with intrahepato-arterial infusion of CDDP (cis-diamminedichloro-platinum II) plus 5-FU (5-fluorouracil); CDDP (0.8-1.0 mg/kg) was given once every 7 or 10-14 days, while 5-FU (250-100 mg/day) was infused daily. A partial response was obtained in 5 of 8 patients with primary liver cancer and in 9 of 14 evaluable patients with metastatic liver cancer. However, severe complications due to bone marrow suppression were observed in 4 patients, 3 of whom died of septicemia and one of enterocolitis. This combined intra-hepato-arterial chemotherapy exerts a synergistic anticancer effect on malignant liver tumors, although the bone marrow suppression associated with it remains to be overcome.

Carcinoembryonic antigen in gastric cancer patients

Carcinoembryonic antigen (CEA) levels were determined in 252 gastric cancer patients. In patients with resectable cancer, the preoperative CEA values and CEA positivity rates were 2.4 +/- 1.5 ng/ml and 7.7% for stage I, 24.9 +/- 72.0 ng/ml and 10.0% for stage II, 21.6 +/- 84.1 ng/ml and 17.9% for stage III, and 6.3 +/- 8.4 ng/ml and 27.1% for stage IV cancers, respectively. In patients with nonresectable cancers, the CEA value was 83.0 +/- 235.5 ng/ml, the CEA positivity rate was 47.8%. Overall, of 252 patients with primary gastric cancer, 47(18.7%) were positive for CEA. In patients with cancer recurrence, the CEA value averaged 41.8 +/- 101.8 ng/ml, the positivity rate was 63%. This rate increased as the cancer stage increased; it was highest in gastric cancer patients with liver metastasis. In 4 of 13 patients with recurrence, an elevation in CEA was observed about 4.8 months before the clinical detection of cancer recurrence. Our results suggest that in gastric cancer patients, the preoperative and periodic postoperative assay of CEA levels has predictive value in determining cancer stage, progression and recurrence.

Negative correlation between cholecystectomy and the subsequent development of large bowel carcinoma in a low-risk Japanese population

The incidence of previous cholecystectomy in a series of 541 patients with colorectal cancer and 1832 patients with stomach cancer was studied. Five patients (0.92 percent) with colorectal cancer and eight (0.44 percent) with stomach cancer had undergone previous cholecystectomy. To avoid biases in the two groups of patients, 416 pairs of patients, comparable in sex, age, and time of admission for cancer treatment, were matched from each group to compare the number of patients who had undergone previous cholecystectomy. Within these matched pairs, three patients with colorectal cancer and two with stomach cancer had histories of cholecystectomy. Hence, no substantial difference was noted between the two groups. In a follow-up study of 461 patients who had undergone cholecystectomy for gallstones, large bowel carcinoma and stomach carcinoma developed in one and six patients, respectively, during an observation period of four to 36 years. The ratio of patients with large bowel cancer to those with stomach cancer observed in this survey was almost equal to the value estimated for the population of Tottori Prefecture, where the majority of the patients reside. The incidence of large bowel carcinoma is not increased among cholecystectomized patients in a low-risk Japanese population.

[Types of surgical operations and cancer development]

Experimental and clinical studies were undertaken to examine whether carcinogenesis in particular organs is influenced by types of surgical operations resulting in an alteration of bile acid excretion and metabolism. A higher incidence of remnant gastric carcinoma was noted in rats receiving gastrectomy with a greater amount of duodenogastric reflux. Furthermore, carcinogenesis was enhanced in gastrectomized rats that had been fed on a high-cholesterol diet causing an increase in bile acid excretion. In a human study, however, there was no relationship between gastrectomy and the incidence of remnant stomach carcinoma. Intestinal surgery alters bile acid metabolism, which may promote colon carcinogenesis. In patients receiving ileocecal resection or right hemicolectomy, the amount of total fecal bile acids was markedly increased as compared to the normal controls. A retrospective study on the incidence of metachronous colorectal cancer in our department showed that the incidence was 12.2% in patients with ileocecal resection in contrast to 4.4% in those with left-side colon resection. These findings suggest that there is a relationship between previous ileocecal resection and the development of metachronous colon carcinoma. We could not obtain any evidence of cholecystectomy having an increased risk for the development of colorectal carcinoma.

Esophageal cancer developed after gastrectomy

Between 1965 and 1983 we treated 129 patients with primary esophageal squamous cell carcinoma. Of these patients, 12 (9.3%) had previously undergone partial gastrectomy and six manifested tumors in the lower thoracic esophagus. Esophagitis of the noncancerous esophageal mucosa surrounding the cancer was confirmed in three of five patients who underwent esophagectomy. We also retrospectively evaluated 130 patients with esophageal cancer who had undergone gastrectomy, including our 12 patients, reported in the Japanese literature between the same period. Between patients with esophageal cancer who had undergone gastrectomy and those who had not there was no age difference; there were more men in the first group. Cancer developed in the lower thoracic esophagus with relatively high frequency in patients who had undergone gastrectomy compared with those who had not. The possibility of an association between gastrectomy and the subsequent development of esophageal cancer, especially lower thoracic esophageal cancer, cannot be ruled out. Further studies are necessary to clarify a possible association.

[Relationship between cholecystectomy and the subsequent development of colorectal carcinoma]

In order to clarify the presence or absence of a relationship between cholecystectomy and the subsequent development of colorectal carcinoma, we compared the incidence of previous cholecystectomy in 448 patients with colorectal cancer and in 1627 with gastric cancer, who had been treated in our clinic during the 21 year period through 1963 to 1983. There was no statistically significant difference in the incidence of previous cholecystectomy between patients with colorectal and gastric cancer. We then performed an historical cohort study covering 461 patients undergoing cholecystectomy for gallstone during the 32 year period from 1949 to 1981 for the subsequent occurrence of carcinoma of the colorectum and stomach. The observed incidence was one in colon cancer and six in gastric cancer, showing a similar proportion of the development of both carcinomas in our district. The present study showed no evidence of cholecystectomy being an increased risk for the development of colorectal carcinoma.

Intra-hepato-arterial infusions of cis-diamminedichloroplatinum (II) and 5-fluorouracil clinically effective for malignant liver tumors

Four hepatocellular cancer patients and 11 metastatic liver cancer patients were treated with intra-hepato-arterial infusions of cis-diamminedichloroplatinum (II) plus 5-fluorouracil. Cis-diamminedichloroplatinum (II) (25-35 mg/m2) was given once a week, 5-fluorouracil (150-180 mg/m2) was infused daily. A partial response was obtained in 3 of 4 patients with primary cancer and in 5 of 9 evaluable metastatic cancer patients; the mean response durations were 27+ weeks in the former and 47+ weeks in the latter. However, severe bone marrow suppression occurred in 4 patients; 3 died of septicemia (2 cases) and massive intra-tracheal bleeding, respectively. This combined intra-hepato-arterial chemotherapy exerts a synergistic anticancer effect on malignant liver tumors, however, the related bone marrow suppression remains to be overcome.