Positron emission tomography scanning is not superior to whole body multidetector helical computed tomography in the preoperative staging of colorectal cancer.

BACKGROUND: The role of positron emission tomography with the glucose analogue [18F] fluoro-2-deoxy-D-glucose (FDG-PET) in the initial staging of disease in patients with primary colorectal cancer (CRC) has not been adequately assessed. AIMS: To evaluate the additional value of FDG-PET as a staging modality, complementary to routine multidetector row computed tomography (MDCT) in patients with CRC. METHODS: Forty four patients with CRC underwent preoperative MDCT and FDG-PET. The accuracy of intraoperative macroscopic staging was also investigated compared with histopathological diagnosis. All FDG-PET images were evaluated with respect to detectability of the primary tumour, lymph node involvement, and distant metastases. Both MDCT and FDG-PET diagnoses and treatment plan were compared with surgical and histopathological results. RESULTS: Thirty seven patients underwent surgery. Tumour detection rate was 95% (42/44) for MDCT, 100% (44/44) for FDG-PET, and 100% (37/37) for intraoperative macroscopic diagnosis. Pathological diagnosis of T factor was T1 in five, T2 in four, T3 in 24, and T4 in four cases. Concordance rate with pathological findings of T factor was 57% (21/37) for MDCT and 62% (23/37) for macroscopic diagnosis. Lymph node involvement was pathologically positive in 19 cases. Regarding N factor, overall accuracy was 62% (23/37) for MDCT, 59% (22/37) for FDG-PET, and 70% (26/37) for macroscopic diagnosis. For all 44 patients, FDG-PET findings resulted in treatment changes in only one (2%) patient. CONCLUSION: FDG-PET is not superior to routine MDCT in the initial staging of primary CRC.

Incidence and recurrence rates of colorectal adenomas estimated by annually repeated colonoscopies on asymptomatic Japanese.

BACKGROUND: Whereas high recurrence rates of colorectal adenomas after polypectomy are widely recognised, little is known of the natural incidence in those with no neoplastic lesions initially. It is also known that single colonoscopy has a significant miss rate. AIMS: To elucidate the incidence and recurrence rates of colorectal neoplasms from a large cohort of asymptomatic Japanese patients on the basis of annually repeated colonoscopies. METHODS: A total of 6225 subjects (4659 men and 1566 women) participating in an annual colonoscopic screening programme and completing three or more colonoscopies were analysed during the 14 year period between 1988 and 2002. Patients were divided into three groups according to the findings of the initial two colonoscopies: 4084 subjects with no neoplasm, 1818 with small adenomas <10 mm, and 323 with advanced lesions, including carcinoma in situ, severe dysplasia, or large adenomas > or =10 mm. Mean age at the second colonoscopy was 48.8 years. RESULTS: For all types of colorectal neoplasms, the incidence rate in those with no initial neoplasm was 7.2%/year whereas recurrence rates in those with small adenomas and advanced lesions were 19.3% and 22.9%/year, respectively. For advanced colorectal lesions, the incidence rate was 0.21%/year whereas recurrence rates in those with small adenomas and advanced lesions were 0.64% and 1.88%/year, respectively. Colorectal neoplasms were in general more likely to develop in males and older subjects. CONCLUSIONS: Although recurrence rates after polypectomy were elevated, the incidence rates in subjects with no neoplastic lesions initially were quite high.

Weak response of helicobacter pylori antibody is high risk for gastric cancer: a cross-sectional study of 10,234 endoscoped Japanese.

BACKGROUND: A large number of endoscoped members of the general Japanese population were surveyed to investigate the relationship between Helicobacter pylori infection and gastric cancer. Special attention was given to antibody titer and age of the subjects. METHODS: We performed gastrointestinal endoscopy and measured serum anti-H. pylori antibody in 10,234 consecutive Japanese who participated in a health examination program. Gastric cancer, when suspected, was confirmed by histology. We graded the H. pylori antibody titer into three groups in accordance with optical density values by ELISA: 'strongly positive', 'weakly positive', and 'negative'. RESULTS: Among the 10,234 subjects (men/women, 7.021/3,213; mean age, 49.1 years), 4,909 (48%) were strongly positive, 1,750 (17%) were weakly positive, and 3,575 (35%) were negative for H. pylori antibody. Thirty-seven cases of gastric cancer were found among the 10,234 subjects (0.36%); 23/4,909 (0.47%) in the strongly positive group, 9/1,750 (0.51%) in the weakly positive group, and 5/3,575 (0.14%) in the negative group. Both the strongly and weakly positive groups showed a higher risk of gastric cancer than the negative group. In the subjects over age 60, the weakly positive group seemed to show the highest risk for gastric cancer. CONCLUSIONS: In this investigation of 10,234 Japanese, based on endoscopy results, those with serum H. pylori antibody had an increased risk for gastric cancer, while those 'weakly positive' showed a high risk, particularly in the elderly.

Inverse background of Helicobacter pylori antibody and pepsinogen in reflux oesophagitis compared with gastric cancer: analysis of 5732 Japanese subjects.

BACKGROUND: The relationship between Helicobacter pylori and reflux oesophagitis remains controversial. AIMS: To evaluate the relationship between H pylori and reflux oesophagitis in a large number of Japanese subjects. SUBJECTS: A total of 5732 consecutive Japanese subjects during a health screening were enrolled. METHODS: Gastrointestinal endoscopy was performed on all subjects. We simultaneously measured serum anti-H pylori antibody and pepsinogen as markers of H pylori infection together with gastric atrophy. The risk of reflux oesophagitis was evaluated in relation to these markers, and the results were compared with those of gastric cancer. RESULTS: Reflux oesophagitis was found in 108 subjects. Both positivity for H pylori antibody (adjusted odds ratio (OR) 0.67 (95% confidence interval 0.45-1.0)) and "low" pepsinogen indicating gastric atrophy (OR 0.35 (0.18-0.68)) were negatively associated with reflux oesophagitis. After subjects were classified into four groups based on positivity or negativity for H pylori antibody and "low" pepsinogen, the prevalence of reflux oesophagitis showed a decreasing trend as H pylori induced gastric atrophy became more severe. The risk of gastric cancer showed an increasing trend, exactly the opposite to that of reflux oesophagitis. CONCLUSIONS: Analysis of a large series of Japanese subjects revealed a decreasing prevalence of reflux oesophagitis in conjunction with progress of gastric atrophy induced by H pylori infection. This pattern was completely opposite to that of gastric cancer cases. A protective role of H pylori for reflux oesophagitis through the development of gastric atrophy has been suggested.

Increased hemostatic molecular markers in patients undergoing anticoagulant therapy.

We evaluated several molecular markers of hemostasis in 92 patients with hypercoagulable states treated with anticoagulant therapy. In all patients, the average values of the international normalized ratio (INR) were 1.70 +/- 0.50; this increase in INR was not, however, significant in patients under thrombotest (TT) monitoring. There were no thrombotic or severe bleeding complications in these patients during a period of 27 months. Plasma levels of thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), D-dimer, and soluble fibrin monomer (sFM) were slightly increased, suggesting that anticoagulant therapy was not completely effective in our Japanese patients based on the values of the TT. The INR was negatively correlated with TT, protein C, and protein S and particularly with TT between 10 and 80%. The range of TT was not correlated with the plasma level of TAT, PPIC, D-dimer, or sFM, but the range of INR was correlated with the plasma level of TAT, D-dimer, and sFM. The percentage of TAT, D-dimer, and sFM within normal range was significantly lower in patients with high INR. These findings show that INR is better than TT for the monitoring of warfarin therapy and that the therapeutic values of INR during the anticoagulant therapy should be > 1.7 in Japanese patients.

Hemostatic markers in Japanese patients undergoing anticoagulant therapy under thrombo-test monitoring.

The objective of this study was to evaluate several molecular markers of hemostasis in 84 patients with hypercoagulable state, treated with warfarin under thrombo-test (TT) monitoring; TT was expressed as percent of control (TT%). In all patients, the average values of international normalized ratio (INR) of prothrombin time (PT;PT-INR) was 1.68+/-0.49; this increase in PT-INR was not, however, significant in patients under TT% monitoring. There were no thrombotic or severe bleeding complications in these patients during a period of 2 years. Plasma levels of thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), D-dimer, and soluble fibrin monomer (sFM) were slightly increased, suggesting that anticoagulant therapy was not completely effective in our Japanese patients based on the values of TT%. Activated partial thromboplastin time, PT-INR, TT% and protein C activity were significantly correlated with the dose of warfarin; fibrinogen, activated thromboplastin, TAT, PPIC, D-dimer, sFM, protein S and thrombomodulin were not significantly correlated with the dose of warfarin. The PT-INR was negatively correlated with TT%, protein C and protein S, and the correlation between PT-INR and TT-INR was better than that between PT-INR and TT%. The range of TT% was not correlated with the plasma levels of TAT, PPIC, D-dimer or sFM, but the range of PT-INR was correlated with the plasma level of TAT, D-dimer and sFM. The percentage of TAT, D-dimer and sFM within normal range was significantly low in patients with high PT-INR. These finding showed that PT-INR is better than TT% for monitoring the anticoagulant therapy with warfarin, and that TT should be expressed as INR. The values of PT-INR should be more than 1.7 during the anticoagulant therapy with warfarin in Japanese patients with high risk of thrombosis.

[Epidemiological evaluation of the protective effect for dying of stomach cancer by screening programme for stomach cancer with applying a method of case-control study--a study of a efficient screening programme for stomach cancer].

An epidemiological evaluation of the protective effect for dying of stomach cancer by screening programme for stomach cancer was conducted with applying a method of case-control study. And also in order to carry out an efficient screening programme, the age groups who should be intensively recommended to receive screening and an optimal screening time interval since the last test were analyzed. 527 cases of men and 273 of women, dying of stomach cancer in the years 1981-1989 in the Awa region of Chiba prefecture, were identified from Chiba Cancer Registry. For each case, 3 controls were drawn at random from Awa living residents (about 162000 inhabitants at 1989 national census), with being matched strictly according to the district of residence, sex and born within 3 years of birth-year. For both cases and controls, the information about the screening history until the date of diagnosis of the case in each matched set was collected respectively from comparison with the screening certification. The results showed a relative risk of 0.417 (99% CI 0.284-0.612) in ever screened men compared with never screened and 0.480 (99% CI 0.280-0.823) in women. The significant reduction in risk was intensively observed on age groups 40-74 years among men and 50-69 years among women and the protective effect continued at most in the following three years since last screening. For an efficiency of screening programme, these age groups should be intensively recommended to receive screening and it is allowable that an optimal screening time interval since last negative test is at most 3 years for general attendance.

Photoinduced Seed Germination of Oenothera biennis L: III. Analysis of the Postinduction Period by Means of Temperature.

The postinduction period of Oenothera biennis L. seed germination was examined by temperature treatments. For all experiments, seeds received a standard 24 hour/24 degrees C preinduction period and 12 hour/32 degrees C photoinduction period. Germination is inhibited by postinduction temperatures above 32 degrees C. When seeds are briefly incubated at 44 degrees C and then transferred to 28 degrees C, they germinate at a much lower percentage than 28 degrees C controls. When thermally inhibited seeds are placed in the dark at 28 degrees C for 20 hours, they can be promoted to germinate by a single pulse of red light. Seeds incubated at 12 degrees C or below immediately after photoinduction enter a lag period in which they germinate slowly or not at all for a long time and then resume germination. The length of the lag period is exponentially related to the postinduction temperature. When seeds are incubated at a low temperature and then transferred to a warm temperature, they germinate much more rapidly than seeds not incubated at a low temperature. A model is proposed which is consistent with these and additional results. In the model, a germination promoter is irreversibly formed from a precursor and the synthesis of the precursor is favored at low temperatures and its degradation is favored at high temperatures.

Photoinduced Seed Germination of Oenothera biennis L: I. General Characteristics.

General characteristics of light-induced germination of Oenothera biennis L. seeds were investigated at 24 degrees C. During dark imbibition, seeds reached maximal respiration in 7 hours and maximal water content and photosensitivity in 24 hours. After dark imbibition of 24 hours, seeds required a long exposure (>36 hours) to red or white light for maximal germination. Two photoperiods (12 and 2 hours) separated by a period of darkness of 10 to 16 hours gave near maximal germination. For the two photoperiod regime, the first light potentiates a reversible phytochrome response by the second light. A 35 degrees C treatment for 2 to 3 hours in the dark immediately prior or subsequent to 8 hours of light caused a higher percentage of germination. A 2 hour treatment at 35 degrees C also potentiates a reversible phytochrome response. Halved seeds germinated at 100% in light or darkness indicating that the light requirement of the seeds is lost in the halving procedure. After-ripened seeds required less light and germinated more rapidly and at higher percentages than seeds tested shortly after maturation.

Photoinduced Seed Germination of Oenothera biennis L: II. Analysis of the Photoinduction Period.

The photoinduction period of Oenothera biennis L. seed germination was analyzed by varying the photoinduction temperature and by substituting red light pulses for continuous red light. At 24 degrees C, seeds require 36 hours of continuous red light for maximal percent germination. The optimal photoinduction temperature is 32 degrees C, with higher and lower temperatures being strongly inhibitory. A 30 minute exposure to far-red light, given immediately after a red light period of 1 to 36 hours, reduces germination by about 25%. Seeds escape from far-red inhibition with a half-time of 5 to 10 hours, depending on the length of the red exposure that precedes the far-red light. Periodic 15 minute pulses of red light can substitute for continuous red light in stimulating germination. Ted red light pulses, with 6 hours of darkness between successive pulses, cause maximal germination. The response to periodic red light is fully reversible by far-red light. Probit analysis of the periodic light response shows that as the length of the dark periods between successive pulses increases, less incident light is needed to induce germination but the population variance in light sensitivity remains constant. Probit analysis of the temperature response shows that as the photoinduction temperature increases from 16 to 32 degrees C, less incident light is needed to induce germination and the population variance in light sensitivity also increases.

Photocontrol of the germination of onoclea spores: v. Analysis of germination processes by means of temperature.

The physiological nature of photoinduced germination of Onoclea sensibilis L. spores was investigated by temporarily applying a range of temperatures, particularly 40 C, before and after short light treatment. Controls were germinated at 25 C.The preinduction phase, during which photosensitivity is maximally developed in the dark, is sensitive to temperature. Treatment at 40 C for 8 or more hours reduces the developed photosensitivity to a minimal level, but the inhibition by 40 C treatment is reversed slowly after subsequent incubation at 25 C in the dark. The postinduction phase, in which dark processes lead to stain uptake and eventually to visible protrusion, is also sensitive to temperature. Inhibition by 40 C occurs shortly after photoinduction, but disappears 6 or more hours after irradiation. Postinduction spores whose germination is inhibited by 40 C treatment recover the ability to germinate after subsequent incubation at 25 C plus a second light treatment. The inhibition and recovery take place faster in postinduction spores than in preinduction spores. In addition, escape from 40 C inhibition is found in the postinduction phase but not in the preinduction phase. Temperatures lower than 25 C exert slow inhibition of both pre- and postinduction processes, and 30 to 35 C act to stimulate germination.In comparison with our earlier work with anaerobiosis and cycloheximide, the postinduction step inhibited by 40 C can be located shortly after the step inhibited by anaerobiosis but before the cycloheximide sensitive step.

Regulation of glucose metabolism and cell wall synthesis in Avena stem segments by gibberellic Acid.

Gibberellic acid (GA) stimulated both the elongation of Avena sativa stem segments and increased synthesis of cell wall material. The effects of GA on glucose metabolism, as related to cell wall synthesis, have been investigated in order to find specific events regulated by GA. GA caused a decline in the levels of glucose, glucose 6-phosphate, and fructose 6-phosphate if exogenous sugar was not supplied to the segments, whereas the hormone caused no change in the levels of glucose 6-phosphate, fructose 6-phosphate, UDP-glucose, or the adenylate energy charge if the segments were incubated in 0.1 m glucose. No GA-induced change could be demonstrated in the activities of hexokinase, phosphoglucomutase, UDP-glucose pyrophosphorylase, or polysaccharide synthetases using UDP-glucose, UDP-galactose, UDP-xylose, and UDP-arabinose as substrates. GA stimulated the activity of GDP-glucose-dependent beta-glucan synthetase by 2- to 4-fold over the control. When glucan synthetase was assayed using UDP-glucose as substrate, only beta-1,3-linked glucan was synthesized in vitro, whereas with GDP-glucose, only beta-1,4-linked glucan was synthesized. These results suggest that one part of the mechanism by which GA stimulates cell wall synthesis concurrently with elongation in Avena stem segments may be through a stimulation of cell wall polysaccharide synthetase activity.

Inhibition of chloroplast electron transport reactions by trifluralin and diallate.

The herbicides trifluralin (alpha,alpha,alpha-trifluoro-2,6-dinitro-N, N-dipropyl-p-toluidine) and diallate (S-[2,3-dichloroallyl] diisopropylthiocarbamate) inhibit electron transport, ATP synthesis, and cytochrome f reduction by isolated spinach (Spinacia oleracea L.) chloroplasts. Both compounds inhibit noncyclic electron transport from H(2)O to ferricyanide more than 90% in coupled chloroplasts at concentrations less than 50 mum. Neither herbicide inhibits electron transport in assays utilizing only photosystem I activity, and the photosystem II reaction elicited by addition of oxidized p-phenylenediamine or 2,5-dimethylquinone is only partially inhibited by herbicide concentrations which block electron flow from H(2)O to ferricyanide. Inhibition of ATP synthesis parallels inhibition of electron flow in all noncyclic assay systems, and cyclic ATP synthesis catalyzed by either diaminodurene or phenazine metho-sulfate is susceptible to inhibition by both herbicides. These results indicate that trifluralin and diallate both inhibit electron flow in isolated chloroplasts at a point in the electron transport chain between the two photosystems.

Possible Interference by an Acid-stable Enzyme during the Extraction of Nucleoside Di- and Triphosphates from Higher Plant Tissues.

Acid extracts from tissues of two solanaceous plants were found to contain a heat-labile, nondialyzable factor which hydrolyzes nucleoside di- and triphosphates to nucleoside monophosphates. This acid-resistant factor shows optimal ATP-hydrolyzing activity at pH 5, whereas practically no activity was detected below pH 3 and above pH 9. It does not hydrolyze sugar phosphates, nucleoside monophosphates, uridine diphosphoglucose, and phosphoenolpyruvate. In order to estimate quantitatively the amount of nucleoside di- and triphosphates in a plant extract, care must be taken to circumvent possible interference by this factor. This is achieved by carefully maintaining the extract below pH 3.

Citric Acid cycle activity in mitochondria isolated from mung bean hypocotyls.

Citric acid cycle activity in mitochondria from mung bean (Phaseolus aureus var. Jumbo) hypocotyls were examined by surveying (a) characteristics of oxidation of cycle intermediates; (b) activities of cycle enzymes in mitochondrial extracts; (c) contents of cycle intermediates and electron transport components in isolated mitochondria; and (d) time-course changes of products formed during oxidation of succinate, malate, and citrate. Isolated mitochondria are deficient in thiamine pyro-phosphate and somewhat so in adenylates, but apparently sufficient in CoA, NAD, and electron transport carriers. Cycle activity in the mitochondria is not directly correlated with the activities of the enzymes measured in extracts. These studies led to the conclusion that the region between malate and citrate is an important regulatory area in citric acid cycle functioning in isolated mung bean mitochondria.

Regulation of malate oxidation in isolated mung bean mitochondria: I. Effects of oxaloacetate, pyruvate, and thiamine pyrophosphate.

In order to investigate the relationship between malate oxidation and subsequent cycle reactions, the effects of oxaloacetate, pyruvate, and thiamine pyrophosphate on malate oxidation in mung bean (Phaseolus aureus var. Jumbo) hypocotyl mitochondria were quantitatively examined. Malate oxidation was optimally stimulated by addition of pyruvate and thiamine pyrophosphate, whose addition lowered the apparent Km for malate from 5 mm to 0.1 mm. Intermediate analysis showed that the stimulatory effect was correlated with removal of oxaloacetate to citrate. Oxaloacetate added alone was shown not to be metabolized until addition of pyruvate and thiamine pyrophosphate; then oxaloacetate was converted in part to pyruvate and also to citrate. These results establish that malate oxidation in mung bean mitochondria is subject to control by oxaloacetate levels, which are primarily determined by the resultant of the activities of malate dehydrogenase, citrate synthase, and pyruvate dehydrogenase.

Regulation of Malate Oxidation in Isolated Mung Bean Mitochondria: II. Role of Adenylates.

Effects of ADP and ATP on products of malate oxidation in the presence or absence of respiratory inhibitors and an uncoupler were investigated in mitochondria isolated from mung bean (Phaseolus aureus var. Jumbo) hypocotyls. Changes in levels of products from malate oxidation generally correlated directly with changes in oxygen uptake. Effects of ADP and ATP were indistinguishable from each other when respiratory chain activity was limited. We concluded that adenylates indirectly act on malate oxidation via the oxidation-reduction status of the pyridine nucleotides which are linked to the respiratory chain. The possibility of allosteric action of ADP and ATP on malate dehydrogenase activity was examined in both intact mitochondria and a partially purified enzyme preparation. Although small inhibition, 16% with 500 muM ATP and 8% with 500 muM ADP, was observed at pH 9.5, this effect was abolished by the addition of magnesium ions or by lowering the pH to 7.2. We concluded that these adenylate effects are probably not a significant factor in regulation under physiological conditions. Furthermore, the equilibrium constant of malate dehydrogenase (to 1.5 x 10(-5)) in both mitochondria and the partially purified enzyme calculated from the steady state level of NADH formed suggested that the enzyme functions in an equilibrium manner in intact mitochondria.

Effect of gibberellic Acid on the plasticity and elasticity of Avena stem segments.

Extensibility characteristics of Avena stem segments treated with gibberellic acid (GA) were investigated in living internodes using a microgrowth method and in partially extracted cell walls subjected to Instron extensometer analysis. Both techniques showed that treatment with GA greatly increases internodal plasticity, but has virtually no effect on internodal elasticity. The increase in plasticity occurred 1 to 2 hours after the initiation of hormone treatment, which is similar to the time of onset of GA-enhanced growth and cell wall synthesis. Cycloheximide was shown to inhibit the effect of GA on plasticity.

Photocontrol of the Germination of Onoclea Spores: IV. Metabolic Changes during Germination.

The changes in levels of metabolites during photoinduced germination of Onoclea sensibilis L. spores are described. Proteins and lipids, which constitute 25 and 20%, respectively, of the unimbibed spores on a dry weight basis, are hydrolyzed at the time of differentiation and elongation of the germling cells and may be utilized for these processes. Sucrose degradation, starch synthesis, and active respiration occur during dark imbibition, but these processes are accelerated by red or far red irradiation. Endogenous sucrose is the probable source of the carbon skeleton for starch synthesis.