[Cancer chemotherapy for gastric cancer patients in the elderly].
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Publications and source records attributed to A Miyamoto.
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We report a patient with hepatocellular carcinoma (HCC) with portal vein thrombosis in the 1st branch who was treated by transcatheter arterial embolization (TAE) and survived more than 3 years. A 58-year old male was diagnosed as having unresectable massive type HCC in the area of S8 with portal vein thrombosis from the P8 branch to the right portal branch. He was treated by TAE via the anterior branch of right hepatic artery. One week later, localized hepatic infarction in the anterior segment was recognized. Five months later, the portal vein thrombosis had disappeared and become necrotic. After 3 years and 4 months, he died of a relapse of a gastric varix, but with no portal thrombosis and a well controlled intra-hepatic recurrence that was treated by repeated TAE. This case suggests that TAE might be effective for cases of HCC with portal vein thrombosis in the 1st branch, if the liver function and portal flow are suitable.
We studied the bioavailability of magnesium (Mg) in spinach after boiling with distilled water, using Mg-deficient growing male rats. The rats were fed a semipurified diet (Mg:0.063 per cent (w/w)) for 3 days. then a Mg-deficient diet (Mg:0.001 per cent (w/w)) for 5 days. They were then divided randomly into 7 groups of 6 rats each, and fed the semipurified diet (Mg: 0.063, 0.045 or 0.027 per cent (w/w)), or the spinach-supplemented diet (10 per cent (w/w) dried and powdered spinach after boiling with distilled water for 3 min at 100 degrees C). The Mg content of the diets supplemented with spinach grown on chemical nutrients, and on manure from pigs, cattle and fowl, was 0.069, 0.051, 0.043 and 0.036 per cent (w/w), respectively. Water intake and volumes of urine and faeces were significantly greater in the rats fed the spinach-supplemented diets than in those fed the semipurified diets. Apparent absorption of Mg, and urinary and faecal excretions of Mg were directly related to Mg intake: no significant difference was observed amongst the groups. Both the ratios of Mg absorption and retention were significantly lower in the rats fed diets supplemented with spinach than in those fed semipurified diets. The plasma Mg level was directly related to Mg intake in the rats fed the semipurified diets and the spinach-supplemented diets. However, the plasma Mg level in the rats fed spinach grown organically on manure from fowl tended to be higher than in the other groups. From these results, it was concluded that bound Mg in spinach was effectively utilized by Mg-deficient rats, however, the absorption and retention rates of Mg in rats fed diets supplemented with spinach were decreased. Possible explanations were discussed.
The regulation of the alpha(1)-adrenoceptor-G protein-phospholipase C (PLC) cascade was investigated in rat cerebral cortex at adult (6-month-old) and senescent (24-month-old). Norepinephrine (NE)-stimulated inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)] production was enhanced 30% during aging. Moreover, maximal NE (50 microM) stimulation was much more effective in stimulating G protein low-K(m) GTPase in cortical membranes from old than adult rats. Immunoreactive G protein subunits (Gqalpha, Gialpha, Goalpha and Gcommonbeta) and PLC-beta(1) isozyme were detected in all membrane preparations. No changes in the G protein subunits and PLC-beta(1) expression were observed with aging. Nanomolar concentration of Gpp[NH]p inhibited basal Ins(1,4,5)P(3) production with a maximum inhibition of 25% in both adult and aged cortical membranes. In contrast, 100 microM Gpp[NH]p-induced stimulation of Ins(1,4,5)P(3) production was potentiated with aging. The two principal divergent pathways of old cortical Ins(1,4,5)P(3) production resulting in the activation and inhibition of PLC-beta(1) activity are abolished by treatment of the membranes with 1 microM U-73122, a putative PLC-beta inhibitor. These results suggest that the cortical PLC-beta(1) isozyme activity may be regulated by both inhibitory and stimulatory G proteins-mediated mechanisms, and that the altered PLC-beta(1) dual regulatory systems could be involved in the pathogenesis of brain aging.
The Notch transmembrane receptors play important roles in precursor survival and cell fate specification during hematopoiesis. To investigate the function of Notch and the signaling events activated by Notch in myeloid development, we expressed truncated forms of Notch1 or Notch2 proteins that either can or cannot activate the core binding factor 1 (CBF1) in 32D (clone 3) myeloblasts. 32D cells proliferate as blasts in the presence of the cytokines, GM-CSF or IL-3, but they initiate differentiation and undergo granulopoiesis in the presence of granulocyte CSF (G-CSF). 32D cells expressing constitutively active forms of Notch1 or Notch2 proteins that signal through the CBF1 pathway maintained significantly higher numbers of viable cells and exhibited less cell death during G-CSF induction compared with controls. They also displayed enhanced entry into granulopoiesis, and inhibited postmitotic terminal differentiation. In contrast, Notch1 constructs that either lacked sequences necessary for CBF1 binding or that failed to localize to the nucleus had little effect. Elevated numbers of viable cells during G-CSF treatment were also observed in 32D cells overexpressing the basic helix-loop-helix protein (bHLH), HES1, consistent with activation of the CBF1 pathway. Taken together, our data suggest that Notch signaling enhances 32D cell survival, promotes entry into granulopoiesis, and inhibits postmitotic differentiation through a CBF1-dependent pathway.
Recently it was suggested that abnormal endothelial function may contribute to the pathophysiological changes observed in preeclampsia (PE). Both nitric oxide (NO) and endothelin-1 (ET-1) are vasoactive substances produced by endothelial cells. NO is a vasodilator and has been believed to be decreased in PE. ET-1 is a vasoconstrictor and has been reported to be increased in PE. We simultaneously measured NO metabolites and ET-1 in sera from women with PE and investigated the correlation of NO and ET-1 concentrations. We obtained serum samples from 11 healthy nonpregnant (NP) women, 16 normotensive pregnant (NTP) women and 17 women with PE. In this study, the serum ET-1 level was assayed by the ET-1 RIA system, and serum NO metabolites were assayed by measuring nitrite (NO2-) and nitrate (NO3-) simultaneously in an HPLC-Griess reaction system. There was a significant correlation between NOx (nitrite + nitrate) and ET-1 in sera from all 44 women (NP, NTP and PE groups) (p<0.001). Nitrite and ET- in sera from each group were not significantly correlated. Nitrate and ET-1 in sera from the NP and NTP groups did not significantly correlate. However, there was a significant correlation between nitrate and ET-1 in sera from the PE group (p<0.05). The serum ET-1 and nitrate concentration in the PE group was significantly higher than in the NP and NTP groups (p<0.05 and p<0.001. respectively). These findings suggest that increased production of nitrate in PE may contribute to homeostatic vasodilation against vasoconstriction caused by a higher ET-1 concentration.
We studied the effects of a selective vasopressin V(1A) receptor antagonist [1-(1-(4-(3-acetylaminopropoxy)benzoyl)-4-piperidyl)-3, 4-dihydro-2(1H)-quinolinone (OPC-21268)] and a selective vasopressin V(2) receptor antagonist [5-dimethylamino-1(4-(2-methylbenzoylamino)benzoyl)-2,3,4, 5-tetrahydro-1H-benzazepine (OPC-31260)] on vasopressin-induced contraction of mesenteric and cremasteric arterioles in urethane-anaesthetized rats. Vasopressin was infused intravenously for 60 min or applied topically to arterioles directly. Vasopressin infusion (50, 100 or 500 ng/kg/min) decreased the diameter of both mesenteric and cremasteric arterioles. Vasopressin (500 ng/kg/min)-induced vasoconstriction was antagonized by OPC-21268 (0. 2, 1.0 and 5.0 mg/kg, i.v.), dose-dependently, but not by OPC-31260. Topically applied vasopressin (4.6x10(-10)-4.6x10(-8) M) dose-dependently constricted both microvessels. Pre-administration of OPC-21268 (5.0 mg/kg, i.v.) completely inhibited topically applied vasopressin-induced vasoconstriction in both microvessels, and OPC-31260 partially inhibited it in cremasteric arterioles. These results suggest that vasopressin induces vasoconstriction in rat mesenteric and cremasteric arterioles mainly by stimulating vasopressin V(1A) receptors, while vasoconstriction in cremasteric arterioles is partly associated with stimulation of vasopressin V(2) receptors.
HYPOTHESIS: The clinical significance of hepatectomy for hepatocellular carcinoma (HCC) is still controversial because of frequent intrahepatic recurrence, which results from either recurrence due to residual intrahepatic metastasis (Rim) or recurrence due to metachronous, multicentric liver carcinogenesis (Rmc). DESIGN: Retrospective review. Disease-free survival curves were obtained by the Kaplan-Meier method and the rates of Rim and Rmc were analyzed using 2 regression lines, based on the evidence that Rmc occurs at a constant rate throughout follow-up, whereas Rim occurs only in the early postoperative period. SETTING: University hospital. PATIENTS: From 1980 to 1996, 241 patients with HCC who underwent curative hepatic resection. MAIN OUTCOME MEASURE: Intrahepatic recurrence. RESULTS: Disease-free survival curves for all patients in the early (within 2 years) and late (4 years after surgery) follow-up were approximated by 2 regression lines, which represent both Rim and Rmc (Y(1) = -3.4X + 48) and only Rmc (Y(2) = -23.1X + 98). Using this approximation, the annual incidence of Rim within 2 years (a(1)-a(2)) was calculated as 19.7% and that of Rmc (a(2)) was 3.4%. The ratio of Rim in tumor recurrence (b(1)-b(2)) was 50%, and that of Rmc (b(1)) was 48%. The ratios of Rmc in patients with stages I and II HCC were 60% and 64%, respectively. In contrast, the values could not be calculated in patients with stages III and IVA because all but 2 patients showed recurrence within 4 years after surgery. CONCLUSION: Tumor recurrence is estimated to result from metachronous liver carcinogenesis in 48% of hepatectomized patients with HCC.
The correlation between scalp EEG, intraoperative electrocorticogram, neuroimaging and histopathology was examined in an epileptic child with diffuse cortical dysplasia. The 6-year-old girl with moderate mental retardation had suffered from intractable complex partial and generalized epilepsies since the age of 2 years. MR images demonstrated unilateral large macrogyria/polymicrogyria and schizencephaly in the right occipital lobe. The epileptic focus was detected on the macrogyria by EEG and single photon emission tomography. However, the intraoperative electrocorticogram showed frequent spikes from the polymicrogyria and no paroxysmal activity in the macrogyria. The polymicrogyria and the macrogyric lesion were resected, using an image-guided system. The histological findings revealed that the macrogyria was covered with and separated by glial bundles. It has been reported that epileptogenicity is produced from abnormal neurons and their arrangement in cortical dysplasia; in this case, however, the major dysplastic lesion had no epileptogenicity; rather the focus might be in the polymicrogyria around the lesion.
A measure to counteract the effects of low or zero gravity is required for long-term space flight, such as the manned Mars mission scheduled by the National Aeronautics and Space administration (NASA) for 2014. We conducted a series of centrifugation experiments with humans, using a short-arm centrifuge (radius 1.8 m, made by First Medical Co., Tokyo, Japan). We employed 6-degree, head-down tilt (HDT) for 4 days to simulate space flight. Ten healthy male volunteers underwent 4-day HDT and a 2-G daily centrifuge load for 60 min in the +Gz direction and measurements, such as haematocrit, 24-h urine volume, body weight and electrocardiogram (ECG) were made. There was no significant increase in the haematocrit during the HDT period, although our previous studies had shown a significant increase during HDT. A 60-min daily load of +2 Gz appears to be effective in reversing the haematocrit increase due to 4-day HDT.
Janus kinases (Jaks) play an important role in signal transduction via cytokine receptors. Tyk2 is a Janus kinase, and we developed tyk2-deficient mice to study the requirement for tyk2 in vivo. Tyk2-deficient mice show no overt developmental abnormalities; however, they display a lack of responsiveness to a small amount of IFNalpha, although a high concentration of IFNalpha can fully transduce its signal even in the absence of tyk2. Furthermore, IL-12-induced T cell function is defective in these mice. In contrast, these mice respond normally to IL-6 and IL-10, both of which activate tyk2 in vitro. These observations demonstrate that tyk2 plays only a restricted role in mediating IFNalpha-dependent signaling while being required in mediating IL-12-dependent biological responses.
We investigated the expression of several candidate gene markers: MAGE-1, MAGE-3, cytokeratin-20 (CK-20), and alpha-fetoprotein (AFP) in tumor tissue and blood specimens from patients with hepatocellular carcinoma to develop a multiple marker reverse transcriptase-polymerase chain reaction (RT-PCR) assay for detection of micrometastasis in circulation. In 24 tumor specimens, the positivity for MAGE-1, MAGE-3, AFP, and CK-20 genes was 71, 67, 88, and 79% respectively, and all specimens expressed at least one marker. Although AFP and CK-20 transcripts were also detected in corresponding noncancerous liver specimens, none of the 22 corresponding normal specimens or seven normal livers were positive for MAGE-1 or MAGE-3 transcripts. In addition, MAGE-1 and MAGE-3 gene transcripts were not detected in any peripheral blood specimens from 31 normal healthy volunteers. MAGE-1, MAGE-3, and AFP transcripts were detected in 9 (12.7%), 3 (4.8%), and 10 (15.9%) of 71 blood specimens from 11 hepatocellular carcinoma patients, respectively, while 19 specimens (26.8%) were positive for at least one marker. Our results indicate that a multimarker RT-PCR assay with cancer-specific markers such as MAGE-1 and MAGE-3 in combination with a liver-specific AFP marker may be a promising diagnostic tool for monitoring hepatocellular carcinoma patients with better sensitivity and specificity.
We report a case of advanced hepatocellular carcinoma (HCC), successfully treated by a combination therapy of alpha-interferon (IFN-alpha) and tegafur/uracil (UFT). A 44-year-old Japanese man who underwent a partial hepatectomy for HCC developed tumor recurrence in the liver 10 months after surgery. Transcatheter arterial chemoembolization (TAE) was performed twice within 7 months, but was ineffective. Later, multiple metastatic lesions appeared in the liver, lung and spine. Following the third TAE, a combination therapy of IFN-alpha (10 x 10(6) units, i.m., t.i.w.) and UFT (300 mg, p.o.d.) was started. The treatment resulted in a fall in serum PIVKA-II (protein induced by vitamin K antagonism) levels from 906 mAU to normal levels and a complete resolution of all lung nodules within 6 months. At the latest follow up 24 months after the initiation of combination treatment, the patient was working full-time and showed no evidence of tumor relapse. A combination therapy of IFN-alpha and UFT may be promising for the treatment of advanced HCC.
Recent findings suggest that the ovarian renin-angiotensin system regulates ovarian function through the paracrine/autocrine actions of angiotensin (Ang) II. The aims of this study were to investigate 1) the endothelial cell capacity to convert Ang I to Ang II, 2) the effects of endocrine and paracrine/autocrine factors on Ang II production in microvascular endothelial cells (MVE) derived from the developing corpora lutea (CL), and 3) the relationship between Ang II peptide concentration and expression of mRNA for angiotensin type 1 and 2 receptors (ATR1 and AT2R) in the bovine CL at different stages of the estrous cycle. When Ang I was added to the MVE at a concentration of 10(-9) M, it was converted to Ang II (21%). The production of Ang II from Ang I time-dependently rose for 24 h. Addition of captopril (an inhibitor of Ang-converting enzyme [ACE]) to the MVE cultures significantly inhibited Ang II production from 6 h to 24 h (P < 0.05). Addition of estradiol-17beta (E(2)) + vascular endothelial growth factor and E(2) + basic fibroblast growth factor to MVE cultures increased Ang II production, whereas E(2) or growth factors alone had no effect. Specific transcription for AT1R and AT2R was detected in bovine CL and MVE. There were no significant changes in Ang II tissue concentration or AT1R mRNA expression using reverse transcription-polymerase chain reaction during the estrous cycle. In contrast, AT2R mRNA expression decreased during the midluteal phase (P < 0.05) and increased to the highest level during the late luteal phase (P < 0.05). Results demonstrated that Ang II is generated from Ang I in MVE isolated from the developing bovine CL, indicating that MVE have ACE activity. In addition, mRNA expression for Ang II receptors was detected in the bovine CL and the luteal MVE. These results suggest that Ang II is produced by actions of the local renin-angiotensin system, at least in part, on MVE in the bovine CL, and that this peptide may be involved in the regulation of luteal function during early development and luteolysis.
Luteal regression is initiated by prostaglandin F(2 alpha) (PGF(2 alpha)). In domestic species and primates, demise of the corpus luteum (CL) enables development of a new preovulatory follicle. However, during early stages of the cycle, which are characterized by massive neovascularization, the CL is refractory to PGF(2 alpha). Our previous studies showed that endothelin-1 (ET-1), which is produced by the endothelial cells lining these blood vessels, plays a crucial role during PGF(2 alpha)-induced luteolysis. Therefore, in this study, we compared the effects of PGF(2 alpha) administered at the early and mid luteal phases on ET-1 and its type A receptors (ETA-R) along with plasma ET-1 and progesterone concentrations, and the mRNA levels of PGF(2 alpha) receptors (PGF(2 alpha)-R) and steroidogenic genes. As expected, ET-1 and ETA-R mRNA levels were markedly induced in midcycle CL exposed to luteolytic dose of PGF(2 alpha) analogue (Cloprostenol). In contrast, neither ET-1 mRNA nor its receptors were elevated when the same dose of PGF(2 alpha) analogue was administered on Day 4 of the cycle. In accordance with ET-1 expression within the CL, plasma ET-1 concentrations were significantly elevated 24 h after PGF(2 alpha) injection only on Day 10 of the cycle. The steroidogenic capacity of the CL (plasma progesterone as well as the mRNA levels of steroidogenic acute regulatory protein and cytochrome P450(scc)) was only affected when PGF(2 alpha) was administered during midcycle. Nevertheless, PGF(2 alpha) elicited certain responses in the early CL: progesterone and oxytocin secretion were elevated, and PGF(2 alpha)-R was transiently affected. Such effects probably result from PGF(2 alpha) acting on luteal steroidogenic cells. These findings may suggest, however, that the cell type mediating the luteolytic actions of PGF(2 alpha), possibly the endothelium, could yet be nonresponsive during the early luteal phase.
We previously proposed that an endothelin-angiotensin-atrial natriuretic peptide system may contribute to inducing ovulation of mature bovine follicles by modulating follicular secretion of steroids and prostaglandins (PGs). Thus, this study aimed to determine the real-time changes in the local release of angiotensin II (Ang II), endothelin (ET), atrial natriuretic peptide (ANP), PGF(2alpha), and steroid hormones from bovine mature follicles during the periovulatory period in vivo. Seven cows were treated for superovulation using FSH and PGF(2alpha) injections. Two dialysis capillary membranes per follicle were surgically implanted into the theca layer of mature follicles and connected to a microdialysis system (MDS). Fractions of the perfusate were collected from Day -1 (Day 0 = LH surge) to Day 3. Five out of seven treated cows were normally ovulated, and the newly formed corpora lutea were observed at the end of the experiment. In these five ovulated cows, the release of estradiol, androstenedione, and progesterone in the theca layer increased (P < 0.05) synchronously with the LH surge. Acute increases in PGF(2alpha) and Ang II concentrations in the ovarian venous plasma (OVP) were observed at 24-48 h after the peak of the LH surge, when multiple ovulations were expected to occur. The follicular Ang II release was low during the pre-LH surge period and rose (P < 0.05) at the beginning of the increase in the LH surge. On the other hand, ET-1 release dropped (P < 0.05) when plasma LH started to increase. However, no clear changes in ANP concentration in the MDS perfusate and plasma were observed. The above local changes in Ang II, PGF(2alpha), as well as steroid hormones were not observed in cows (n = 2) that did not show an LH surge and ovulation. The present results demonstrate for the first time the local release of Ang II, ET-1, and ANP from the bovine mature follicle in real-time in vivo and show that Ang II and PGF(2alpha) concentrations in the OVP acutely increase around the time of ovulation. The overall results support the concept of a local functional ET-Ang-ANP system in the bovine mature follicle that may be involved in the ovulatory process.
PURPOSE: Human skeletal muscle probably atrophies as a result of spaceflight, but few studies have examined this issue. Thus, little is known about the influence of microgravity upon human skeletal muscle, nor is it possible to assess the validity of ground based models of spaceflight. This study tested the hypothesis that the magnitude of spaceflight induced muscle atrophy would be a function of flight duration and greater than that of bed rest. METHODS: Three astronauts flew 9, 15, and 16 d in space. Volume of the knee extensor (quadriceps femoris), knee flexor (hamstrings, sartorius, and gracilis), and plantar flexor (triceps surae) muscle groups was measured using magnetic resonance imaging before and after spaceflight and during recovery. The volume of each muscle group in each image was determined by multiplying cross-sectional area by slice thickness. These values were subsequently summed to calculate muscle volume. RESULTS: Volume changes in the knee extensor, knee flexor, and plantar flexor muscle groups ranged from -15.4 to -5.5, -14.1 to -5.6, and -8.8 to -15.9%, respectively. Muscle volume decreases normalized by flight duration ranged from 0.62 to 1.04% x d(-1). These relative changes appeared to be greater than those that we have reported previously for bed rest (Akima et al., J. Gravitat. Physiol. 4:15-22, 1997). CONCLUSIONS: These results suggest that atrophy as a result of at least 2 wk of spaceflight varied among individuals and muscle groups and that the degree of atrophy appeared to be greater than that induced by 20 d of bed rest.
Notch proteins are transmembrane receptors that mediate intercell communication and direct individual cell fate decisions. The activated intracellular form of Notch, NotchIC, translocates to the nucleus, where it targets the DNA binding protein CBF1. CBF1 mediates transcriptional repression through the recruitment of an SMRT-histone deacetylase-containing corepressor complex. We have examined the mechanism whereby NotchIC overcomes CBF1-mediated transcriptional repression. We identified SKIP (Ski-interacting protein) as a CBF1 binding protein in a yeast two-hybrid screen. Both CBF1 and SKIP are highly conserved evolutionarily, and the SKIP-CBF1 interaction is also conserved in assays using the Caenorhabditis elegans and Drosophila melanogaster SKIP homologs. Protein-protein interaction assays demonstrated interaction between SKIP and the corepressor SMRT. More surprisingly, SKIP also interacted with NotchIC. The SMRT and NotchIC interactions were mutually exclusive. In competition binding experiments SMRT displaced NotchIC from CBF1 and from SKIP. Contact with SKIP is required for biological activity of NotchIC. A mutation in the fourth ankyrin repeat that abolished Notch signal transduction did not affect interaction with CBF1 but abolished interaction with SKIP. Further, NotchIC was unable to block muscle cell differentiation in myoblasts expressing antisense SKIP. The results suggest a model in which NotchIC activates responsive promoters by competing with the SMRT-corepressor complex for contacts on both CBF1 and SKIP.