Mutational analysis of the p53 and K-ras genes and allelotype study of the Rb-1 gene for investigating the pathogenesis of combined hapatocellular-cholangiocellular carcinomas

Because combined hepatocellular-cholangiocellular carcinoma is rare and its biological features and pathogenesis have not been well established, we investigated alterations of the p53, K-ras and Rb-1 genes, as well as expression patterns of carcinoembryonic antigen and keratin, in seven combined hepatocellular-cholangiocarcinomas out of 557 hepatocellular carcinomas autopsied at Tokyo University during 30 years. Mutations of the p53 gene were found in two cases, at codon 244 (GGC to TGC) in the cholangiocellular carcinoma component of case 1 (mixed type, showing an intimate intermingling of both elements) and at codon 234 (TAC to AAC) in both components of case 5 (combined type, consisting of contiguous but independent masses of both elements). Mutation of the K-ras gene (codon 12, GGT to GAT) was seen only in the cholangiocellular carcinoma component of clinically apparent double cancer, case 6. Allelic alteration of the Rb-1 gene was observed in two cases, deletion of both alleles in the hepatocellular carcinoma component of case 3 (combined type) and replication error of the same pattern in both components of case 4 (mixed type). Immunohistochemical analysis showed that the hepatocellular carcinoma components of five cases (cases 2, 3, 5, 6, 7) were immunoreactive for keratin, suggesting biliary epithelial transformation. In four of the five cases (cases 3 and 5 combined, case 7 mixed and case 6 double cancer), cholangiocellular carcinoma components were also positive for keratin. These results suggest that both components of combined hepatocellular-cholangiocarcinoma have the same genetic and phenotypic character and might have arisen from the same origin in some cases.

Chemosensory neurons function in parallel to mediate a pheromone response in C. elegans

Formation of the C. elegans dauer larva is repressed by the chemosensory neurons ADF, ASI, and ASG. Mutant analysis has defined two parallel genetic pathways that control dauer formation. By killing neurons in these mutants, we show that mutations in one of these genetic pathways disrupt dauer repression by ADF, ASI, and ASG. One gene in this pathway is daf-7, which encodes a TGFbeta-related protein. We find that daf-7::GFP fusions are expressed specifically in ASI and that expression is regulated by dauer-inducing sensory stimuli. We also show that a different chemosensory neuron, ASJ, functions in parallel to these neurons to induce dauer formation. Mutations in the second genetic pathway activate dauer formation in an ASJ-dependent manner. Thus, the genetic redundancy in this process is reflected at the neuronal level.

Late development of hydrothorax induced by a central venous catheter: report of a case

We report herein the case of a 47-year-old woman who suffered a hydrothorax induced by a central venous catheter (CVC) which had been placed to facilitate total parenteral nutrition following a left sleeve pneumonectomy for lung cancer. The CVC was inserted into the superior vena cava (SVC) through the left subclavian vein after the operation; however, the tip inadvertently turned upward and came in contact with the lateral wall of the SVC. The patient suddenly developed dyspnea due to a right-sided hydrothorax 47 days after the insertion of the catheter. Indocyamine green administered through the catheter was thereafter found in the pleural fluid. The continuous mechanical force of the catheter tip against the SVC wall was thus considered to be the cause of this life-threatening delayed hydrothorax.

Effects of footshock stress on regional brain monoamine metabolism and the acquisition of conditioned freezing in rats previously exposed to repeated methamphetamine

1. Effects of footshock stress on regional brain DA and 5-HT metabolism and the acquisition of conditioned fear in male Wistar-King rats previously exposed to repeated MA were examined. 2. MA-pretreated rats exhibited more freezing than control rats in the conditioned fear test. 3. The HVA levels in the striatum was elevated by footshock only in MA-treated rats but not saline-treated rats. Furthermore, MA-treated rats showed increased metabolism of DA in the mPFC, even when placed in the shock chamber without shocks. 4. The brain serotonergic responsiveness to fear conditioning was also attenuated by repeated administration of MA. 5. These results suggest that not only the brain DA systems but also the brain 5-HT systems play an important role for the development of MA-induced emotional hypersensitivity to stress.

Characterization of the newly constructed domains that replace P5abc within the Tetrahymena ribozyme

The P5abc domain of the Tetrahymena ribozyme has been shown to function as an activator that enhances core catalytic activity of the ribozyme. We reported previously that several new domains in that their primary sequences are different from that of P5abc are also capable of activating the ribozyme. It was unclear whether the mechanism of activation by the new domains is identical to that by P5abc. We have investigated structural and functional properties of the new domains and obtained evidence that strongly indicates that a particular domain activates the ribozyme in a different manner from that by P5abc.

Hepatocyte growth factor (HGF) produced by peritoneal fibroblasts may affect mesothelial cell morphology and promote peritoneal dissemination

Mesothelial cell monolayers have been reported to prevent infiltration of cancer cells into the peritoneum. We have previously reported that peritoneal fibrosis induced by gastric cancer cells prior to metastatization may provide a congenial environment for peritoneal metastases. In this study, we investigated the effects of peritoneal fibroblasts on peritoneal mesothelial cell morphology. Human gastric cancer (OCUM-2MD3), peritoneal fibroblast (NF-2P) and mesothelial (MS-1) cell lines were established in our laboratory. Histology of the peritoneum was investigated following intraperitoneal inoculation of serum-free conditioned media (SF-CM) from OCUM-2MD3 cells into nude mice. SF-CM from peritoneal fibroblasts was added to monolayer-cultured mesothelial cells, and their morphology was examined by phase-contrast microscopy. This experiment was conducted in the presence and absence of neutralizing antibodies against various factors. Mesothelial cells exposed to fibroblasts proliferation became hemispherical and separated from each other, while unexposed mesothelium remained as a flat monolayer. Cultured-mesothelial cells rounded up or exhibited a fibroblast-like shape following the addition of peritoneal fibroblast SF-CM. Anti-hepatocyte growth factor (HGF) neutralizing antibody partly inhibited this effect. We suggest that soluble factors, such as HGF, produced by peritoneal fibroblasts affect the morphology of mesothelial cells in monolayers so that the resulting environment may become prone to the peritoneal dissemination of cancer cells.

Survival rates of patients with metastatic spinal cancer after scintigraphic detection of abnormal radioactive accumulation

STUDY DESIGN

This retrospective study analyzes the timing of spinal metastases and the survivability of patients with cancer after the detection of spinal metastases.

OBJECTIVE

To evaluate the timing of spinal metastases in primary lesions and the survivability of patients with metastatic spinal tumors.

SUMMARY OF BACKGROUND DATA

Few studies have analyzed the influence of primary lesions on survival rates of patients with metastatic spinal tumors.

METHODS

This is a review of bone scintigraphy that was performed serially in patients with pulmonary cancer, breast cancer, prostatic cancer, cervical cancer, renal cancer, and gastric cancer from 1980 to 1991. To exclude false positive cases, the spinal areas showing abnormal accumulation on bone scintigrams were further examined by other methods of diagnostic imaging. The timing of scintigraphic detection of spinal metastases and the survivability were studied in 425 patients with spinal metastases. The survivability after spinal accumulation was determined by the Kaplan-Meier survival curve.

RESULTS

The mean period, from the diagnosis of the primary lesion to the detection of abnormal accumulation in the spine, was shortest in pulmonary cancer (3.6 +/- 6.1 months), and it was longest in breast cancer (29.4 +/- 33.5 months). The 1-year survival rate was high in breast cancer (78%) and prostatic cancer (83%), and it was low in pulmonary cancer (22%) and gastric cancer (0%), respectively. The 6-month survival rate of gastric cancer was 15%.

CONCLUSIONS

When managing metastatic spinal tumors, it is essential to select therapeutic methods based on adequate consideration of the features of primary lesions and the expected prognosis.

Effect of citalopram, a selective serotonin reuptake inhibitor, on the acquisition of conditioned freezing

The present study examined the effects of the selective serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibitor citalopram on the acquisition of conditioned freezing, an index of anxiety. Acute treatment with citalopram (1-10 mg/kg) dose dependently prevented the acquisition of conditioned freezing, while acute treatment with noradrenaline or dopamine reuptake inhibitors failed. The acute effect of citalopram was not antagonized by the 5-HT1A receptor antagonist NAN190, 1-(2-methoxyphenyl)-4-[4-(2-phthalimmido)butyl]piperazine or the 5-HT2A/2C receptor antagonist ICI169,369, 2-(2-dimethylaminoethylthio)-3-phenylquinoline hydrochloride. These results indicate that selective 5-HT reuptake inhibitors reduce not only the expression of conditioned freezing as reported previously, but also the acquisition of conditioned freezing. Both these effects of selective 5-HT reuptake inhibitors may be related to their clinical efficacy in the treatment of anxiety disorders.

[Chromosomal numerical aberrations in bladder cancer detected by fluorescence in situ hybridization (FISH)]

BACKGROUND

Chromosomal aberration and DNA ploidy pattern are regarded as prognostic markers of the bladder cancer. In this paper, numerical chromosomal aberrations were analysed by interphase fluorescence in situ hybridization (FISH) for the cases with bladder cancer.

METHODS

FISH was carried out on touch smear of 35 cases of transitional cell carcinoma of the urinary bladder. DNA probes were digoxigenin labeled alpha/beta-satellite probes for chromosome 1, 7, 9, 11, 17, Y. FISH signals were counted using confocal laser microscope (LSM GB 200, OLYMPUS. Touch smear preparations were also examined with image cytometer (CAS 200, Becton Dickinson) and DNA index was obtained.

RESULTS

Numerical chromosomal aberrations were observed in 9 of 21 (42.9%) diploid cases and in all 14 non-diploid cases. Among 6 kinds of chromosome examined imbalance was observed and most common imbalance was loss of chromosome 9 (11 cases, 32.4%).

CONCLUSION

Even in the diploid tumors, chromosomal aberration was observed. Combined analysis of chromosomal aberration and DNA ploidy pattern was easily and quickly performed in our series. Clinical application could be possible and possess diagnostic and prognostic value.

Direct quantification of pentosidine in urine and serum by HPLC with column switching

Concentrations of pentosidine, an advanced glycation end product, are increased in aging, diabetes mellitus, and uremia. Using HPLC with column switching, we developed a direct method of measuring pentosidine in urine and serum. We inject the sample directly onto a gel-filtration precolumn, select ("heart-cut") the eluate fraction containing pentosidine, and introduce this fraction into a reversed-phased column by use of a switching valve. The recovery rate of the complete method was 97.7-99.9%. The intraassay CV was 5.7%, and the interassay CV was 5.8%. The calibration curve showed significant linearity (r = 0.998, P = 0.0001). We examined urinary concentrations of pentosidine in 12 diabetic patients (mean +/- SD, 8.7 +/- 2.3 micromol/mol of creatinine), 32 patients with chronic renal failure (CRF; 36.1 +/- 39.0), 19 osteoporotic patients (7.9 +/- 5.3), and 29 healthy control subjects (5.2 +/- 2.3). In CRF, urinary pentosidine in the patients undergoing hemodialysis was significantly higher than in CRF patients not being treated by hemodialysis (mean, 58.1 vs 18.2; P <0.001). Also, concentrations of urinary and serum pentosidine were significantly correlated (r = 0.797, P = 0.0011). Because this method does not require pretreatment of samples, it is convenient and useful for measuring urinary and serum pentosidine.

A multicenter validation of regional cerebral blood flow quantitation using [123I]iodoamphetamine and single photon emission computed tomography

Recently, two methods have been proposed for regional cerebral blood flow (rCBF) quantitation using [123I]iodoamphetamine (IMP) and single-photon emission computed tomography (SPECT). The table look-up (TLU) method has been shown to provide both rCBF and volume of distribution, Vd, images from two SPECT scans, while a single-scan autoradiographic (ARG) technique provided rCBF using a fixed and assumed Vd. In both methods, a single blood sample was referred to calibrate the previously determined standard input function. The present multicenter project was designed to evaluate the accuracy of both methods for use as clinical investigative tools. Ten independent institutions performed [123I]IMP-SPECT studies according to both methods in 76 subjects (10 normal volunteers, 32 patients with cerebrovascular disease, and 34 patients with other diseases). Calculated rCBF values were compared with those obtained by the following reference methods available in the participating institutions; [15O] H2O positron emission tomography (PET) (five institutions), [133Xe]SPECT (four institutions), and the [123I]IMP microsphere method (three institutions). Both ARG and TLU methods provided rCBF values that were significantly correlated with those measured by the [15O] H2O PET technique (p < 0.001 for all subjects; overall regression equation, y = 15.14 + 0.54x) and those measured by the [123I]IMP-microsphere method (p < 0.001 for all subjects: y = 2.0 + 0.80x). Significant correlation (p < 0.05) was observed in 18 of 24 subjects studied with the [133Xe] SPECT reference technique (overall regression equation, y = 15.0 + 0.55x). Mean cortical gray matter rCBF in a group of normal subject was 43.9 +/- 3.3 and 43.4 +/- 2.0 ml/min/100 g for the ARG and TLU methods, respectively. Regional Vd of [123I]IMP estimated by the TLU method was 45 ml/ml +/- 20% in the normal cortical region. Close agreement between ARG and TLU rCBF values was observed (y = -3.21 + 1.07x, r = 0.97), confirming the validity of assuming a fixed Vd in the ARG method. Results of this study demonstrate that both the ARG and TLU methods accurately and reliably estimate rCBF in a variety of clinical settings.

[The complete band4.2 deficiency in human red cells]

The complete band4.2 deficiency with a point mutation (GCT-->ACT at codon142: Nippon type) in red cell membrane protein4.2 gene is specific for the Japanese population. The biochemical properties of band4.2 protein have been studied extensively. However, the physiolosical functions of this protein in situ have been unknown. Therefore, we tried to clarify the physiological role of band4.2 by biochemical, biophysical and electron microscopic studies in the patient with the Nippon type mutation. Band4.2 deficient red cells demonstrated significant abnormalities in the function of both the cytoskeletal network and band3 protein, as summarized in our results. 1 Deformability of red cell membrane was decreased when heat-treated up to 48 degrees C. 2 Under the these conditions, the cytoskeletal network became markedly disrupted, and the number of intramembrane particles was reduced with a shift to larger sizes, indicating the possibility of increased oligomerization of band3 molecules in the red cells. 3 The lateral and rotational mobility of band3 in the red cells was substantially increased. 4 Band4.2 protein was found to bind to spectrin in solution and to promote the binding of spectrin to ankyrin-stripped inside-out vesicles. These results indicate the possibility that band4.2 may play a role in connecting the cytoskeletal network to band3 protein as a kind of anchoring protein.

Multimodal treatment of stage IVa hepatocellular carcinoma

BACKGROUND/AIMS

The effectiveness of multimodal therapy for Stage IVa hepatocellular carcinoma was investigated.

MATERIAL AND METHODS

Between 1982 and 1994, 40 patients with primary Stage IVa tumors were treated in our clinical unit.

RESULTS

The overall survival rate was 79.7% at 1 year, 37.0% at 3 years, and 20.8% at 5 years. However, the most successful multimodal therapy, a combination of hepatectomy, embolization, and ethanol injection, achieved significantly better results (92.9% at 1 year, 59.6% at 3 years, and 47.7% at 5 years). This improved survival could still be obtained by multimodal therapy, even when surgical resection was incomplete.

CONCLUSION

These results suggest that multimodal therapy including hepatectomy can be recommended for improving the survival of patients with Stage IVa hepatocellular carcinoma.

Inhibition of the respiratory pattern-generating neurons by an identified whole-body withdrawal interneuron of Lymnaea stagnalis

Respiration and the whole-body withdrawal are two incompatible behaviors in the freshwater snail Lymnaea stagnalis. Whole-body withdrawal behavior is believed to be higher on the behavioral hierarchy than respiratory behavior. A central pattern generator (CPG) underlies respiratory behavior; whole-body withdrawal is mediated by a network of electrically coupled neurons. In this study, we provide evidence that the behavioral hierarchy between the whole-body withdrawal and the respiratory behaviors is established at the interneuronal level. We demonstrate that an identified whole-body withdrawal interneuron inhibits both muscular and neuronal components of the respiratory behavior in Lymnaea stagnalis. A pair of identified, electrically coupled interneurons, termed left and right pedal dorsal 11 (L/RPeD11), coordinates the whole-body withdrawal behavior in Lymnaea stagnalis. In the present study, RPeD11 inhibited spontaneously occurring respiratory CPG activity in isolated brain preparations. In addition, electrical stimulation of RPeD11 in a semi-intact preparation also inhibited respiratory CPG interneuron RPeD1. The synaptic connections between RPeD11 and the respiratory CPG neurons RPeD1 and visceral dorsal 4 (VD4) persisted in the presence of high-Ca2+/high-Mg2+ saline, suggesting the possibility that they may be monosynaptic. In a semi-intact preparation (lung&shy;mantle, pneumostome and central nervous system), electrical stimulation of RPeD11 induced pneumostome and columellar muscle contractions while inhibiting the activity of RPeD1. Moreover, mechanical stimulation of the respiratory orifice, the pneumostome, excited RPeD11, while its effects on the respiratory CPG neuron (RPeD1) were inhibitory. To determine the monosynaptic nature of connections between RPeD11 and the respiratory CPG neurons in the intact nervous system, we constructed these synapses in culture. RPeD11 and individual respiratory interneurons were isolated from their respective ganglia and co-cultured under conditions that support neurite outgrowth. Following neuritic overlap, RPeD11 was found to establish inhibitory synapses with the respiratory interneurons, supporting the hypothesis that these synaptic connections are likely to be monosynaptic in the intact central nervous system.

Pravastatin reduces restenosis after coronary angioplasty of high grade stenotic lesions: results of SHIPS (SHIga Pravastatin Study)

We conducted a multicenter prospective, randomized, double-blind, placebo-controlled trial to test whether pravastatin, a hydroxymethyl glutaryl coenzyme A reductase inhibitor, can decrease restenosis after percutaneous transluminal coronary angioplasty (PTCA). Pravastatin 10 mg twice daily was begun at least 10 days prior to elective PTCA in patients with total cholesterol less than 280 mg/dl. The end-point was a between-group comparison of the frequency of restenosis defined as a more than 50% loss of the initial gain in diameter stenosis at the PTCA site at 3 months during follow-up by automated quantitative coronary arteriography. Of 207 patients randomly assigned to study groups, 139 patients underwent PTCA; 133 procedures were successful, and 124 patients underwent follow-up angiography at 3 months, and 179 lesions (85 pravastatin, 94 placebo) in 124 patients (62 pravastatin, 62 placebo) were analyzed. The two groups were comparable for baseline characteristics. Total cholesterol decreased by 19.6% in the pravastatin group (p < 0.001) but not in the placebo group. Although the restenosis rate was not different in the two groups (29.4% in pravastatin vs. 39.4% in placebo, p = 0.215) as a whole, it was reduced to about one fifth (8.8%) in the pravastatin group compared with 44.8% in the placebo group (p = 0.0011) when the comparison was restricted to high grade lesions (> or = 75% diameter stenosis, 34 lesions in pravastatin, 29 lesions in placebo). Pravastatin thus reduces restenosis after PTCA of high grade lesions.

Rapid coronary vasodilation by nitroglycerin tapes

We analyzed the acute, direct effects of nitroglycerin (NTG) tape on the coronary arteries and hemodynamics in 38 patients who underwent coronary angiography. The diameters of the 3 main coronary arteries were compared among the angiograms obtained at baseline, 15 minutes following transdermal administration of 10 mg (8 patients) or 25 mg (30 patients) of NTG (Millisrol tape), and after intracoronary injection of 2.5 mg isosorbide dinitrate (ISDN). Only the left main trunk and proximal portion of the left anterior descending artery dilated after 10 mg of transdermal NTG administration (p < 0.05). However, every measured coronary segment (segments 1-8, 11, and 13) dilated (p < 0.05) after 25 mg of NTG. Systemic blood pressure decreased slightly but significantly from 150 +/- 22 to 147 +/- 21 mmHg during the study, with no change in heart rate. Left ventricular end-diastolic pressure decreased significantly from 16 +/- 7 to 14 +/- 5 mmHg. We conclude that 25 mg of transdermal NTG tape dilates coronary arteries and is applicable for acute coronary syndrome, with few complications.

Renal cortical retention of contrast medium after angiography as assessed by delayed CT: a multivariate analysis

Renal cortical retention (RCR) of contrast medium discovered by delayed X-ray examination is sometimes reported in patients with problems in the urinary system. However, we frequently found RCR even in patients with normal renal function. Therefore, we examined the incidence and factors involved in RCR by delayed computed tomography (CT) 12-24 hours after angiography in 168 patients. RCR was found in 80 of 168 cases (48%). Ioxaglate (60%) and iohexol (60%) showed higher incidences of RCR than diatrizoate (37%) and iopamidol (37%). Multivariate logistic regression analysis was performed to determine the predisposing factors of RCR. Dose of administered contrast medium by body weight (p = 0.004), age (p = 0.009), sex (p = 0.013), type of contrast medium (p = 0.003), serum albumin (p = 0.011), and serum creatinine (p = 0.002) were identified as significant and independent predisposing factors of RCR. We suggest that RCR is not a rare phenomenon if delayed CT is carried out.

Prevention by 2-mercaptoethane sulfonate and N-acetylcysteine of renal oxidative damage in rats treated with ferric nitrilotriacetate

Ferric nitrilotriacetate (Fe-NTA) is a renal toxicant and carcinogen in rats and mice. We found that its administration results in formation of 4-hydroxy-2-nonenal (HNE) in the renal proximal tubule cells of rats, and 8-hydroxydeoxyguanosine (8-OHdG) adducts in their DNA, suggesting a role for oxidative stress. Since 2-mercaptoethane sulfonate (MESNA) and N-acetylcysteine (NAC), administered orally, have been shown to increase the kidney levels of free thiol groups, their influence on the renal toxicity and carcinogenicity induced by Fe-NTA was examined in the present study. Male Wistar rats were intraperitoneally injected with Fe-NTA (12 mg Fe/kg), and MESNA (100 mg/kg) or NAC (200 mg/kg) was given orally 1 h before and 1 h after this treatment. The animals were killed for tissue analyses 3 h after the Fe-NTA exposure. In accord with our previous reports, HNE-modified protein was detected in the proximal tubules of Fe-NTA-treated rats by means of immunohistochemistry. Likewise, levels of 8-OHdG in the renal nuclear DNA, lipid peroxides as thiobarbituric acid-reactive substances in the kidneys, and blood urea nitrogen and creatinine in the serum were significantly increased by the Fe-NTA treatment. All of these changes were completely inhibited by oral administration of MESNA or NAC. These results suggest that both of these compounds can prevent the oxidative stress induced by Fe-NTA.

The effect of cyclosporin A administration on bone metabolism in the rat evaluated by biochemical markers

We investigated the effects of cyclosporin A (CsA), an immunosuppressive agent, on bone remodeling in 6 rats compared to 6 controls, using a histomorphometric technique and biochemical markers for bone metabolism. With an oral daily dose of 15 mg CsA/kg of body weight for 28 days, the trabecular bone volume in CsA administered rats was significantly lower than that in control rats, which indicates bone loss in CsA rats. In CsA rats, bone resorption increased, and urinary pyridinoline (Pyr) significantly increased on day 28 compared with control rats. In contrast, bone formation assessed by serum osteocalcin and osteoid volume had no remarkable changes. These results suggest that administration of CsA for 28 days induces bone loss due to uncoupling between bone resorption and bone formation.

Gene expression of insulin signal-transduction pathway intermediates is lower in rats fed a beef tallow diet than in rats fed a safflower oil diet

To elucidate the effects of dietary fatty acid composition on the insulin signaling pathway, we measured the gene expression of the earliest steps in the insulin action pathway in skeletal muscle of rats fed a safflower oil diet or a beef tallow diet. Rats were meal-fed an isoenergetic diet based on either safflower oil or beef tallow for 8 weeks. Both diets provided 45%, 35%, and 20% of energy as fat, carbohydrate, and protein, respectively. Insulin resistance, assessed from the diurnal rhythm of plasma glucose and insulin and the oral glucose tolerance test (OGTT), developed in rats fed a beef tallow diet. Body fat content was greater in rats fed a beef tallow diet versus a safflower oil diet. The level of insulin receptor mRNA, relative expression of the insulin receptor mRNA isoforms, and receptor protein were not affected by the composition of dietary fatty acids. The abundance of insulin receptor substrate-1 (IRS-1) and phosphatidylinositol (PI) 3-kinase mRNA and protein was significantly lower in rats fed a beef tallow diet versus a safflower oil diet. We conclude that long-term feeding of a high-fat diet with saturated fatty acids induces decrease in IRS-1 and PI 3-kinase mRNA and protein levels, causing insulin resistance in skeletal muscle.

Direct quantification of pentosidine in urine and serum by HPLC with column switching

Concentrations of pentosidine, an advanced glycation end product, are increased in aging, diabetes mellitus, and uremia. Using HPLC with column switching, we developed a direct method of measuring pentosidine in urine and serum. We inject the sample directly onto a gel-filtration precolumn, select ("heart-cut") the eluate fraction containing pentosidine, and introduce this fraction into a reversed-phased column by use of a switching valve. The recovery rate of the complete method was 97.7-99.9%. The intraassay CV was 5.7%, and the interassay CV was 5.8%. The calibration curve showed significant linearity (r = 0.998, P = 0.0001). We examined urinary concentrations of pentosidine in 12 diabetic patients (mean +/- SD, 8.7 +/- 2.3 micromol/mol of creatinine), 32 patients with chronic renal failure (CRF; 36.1 +/- 39.0), 19 osteoporotic patients (7.9 +/- 5.3), and 29 healthy control subjects (5.2 +/- 2.3). In CRF, urinary pentosidine in the patients undergoing hemodialysis was significantly higher than in CRF patients not being treated by hemodialysis (mean, 58.1 vs 18.2; P &lt;0.001). Also, concentrations of urinary and serum pentosidine were significantly correlated (r = 0.797, P = 0.0011). Because this method does not require pretreatment of samples, it is convenient and useful for measuring urinary and serum pentosidine.

Effects of growth hormone and insulin-like growth factor 1 (IGF-1) treatments on the nitrogen metabolism and hepatic IGF-1-messenger RNA expression in postoperative parenterally fed rats

BACKGROUND

Few studies have made direct comparisons of the metabolic effects of growth hormone (GH) and insulin-like growth factor 1 (IGF-1). We have assessed the dose-dependent effects of GH and IGF-1 treatments on nitrogen metabolism, intestinal structure, and hepatic IGF-1-messenger RNA (mRNA) expression in postoperative parenterally fed rats.

METHODS

Rats were maintained on total parenteral nutrition (TPN) for 3 days after gastrectomy. GH (0.4 or 0.8 IU/kg/d) or IGF-1 (1,2, or 4 mg/kg/d) was infused throughout the experimental period. Anabolic effects of GH and IGF-1 were assessed by body weight change, nitrogen excretion, and whole-body protein turnover. Organ weights, intestinal structure, plasma IGF-1 levels and hepatic IGF-1-mRNA contents were also determined.

RESULTS

Both GH and IGF-1 attenuated body weight loss and nitrogen excretion and increased whole-body protein synthesis and spleen weight. These observations suggest that the anabolic effects of 1 mg/kg/d of IGF-1 were equivalent to those of 0.66 IU/kg/d of GH. IGF-1, but not GH, reduced atrophy of the intestinal mucosa. GH treatment increased hepatic IGF-1-mRNA and the plasma IGF-1 level, whereas IGF-1 treatment increased the plasma IGF-1 level with no change in the hepatic IGF-1-mRNA content.

CONCLUSIONS

Administration of GH or IGF-1 attenuates catabolism after surgery. The anabolic effects of 1 mg/kg/d of IGF-1 are equivalent to those of 0.66 IU/kg/d of GH. IGF-1 reduces intestinal mucosal atrophy. GH increases hepatic IGF-1-mRNA and the plasma IGF-1 level.

Comparison of fluorine-18-fluorodeoxyglucose and carbon-11-methionine PET in detection of malignant tumors

Two commonly used tumor-seeking agents for PET are 2-deoxy-2-18F-fluoro-D-glucose (FDG) and L-methyl-11C-methionine (Met). This study compared FDG and Met in detecting residual or recurrent malignant tumors in the same patients.

METHODS

Thirty-four lesions in 24 patients with clinically suspected recurrent or residual tumors were studied with PET using Met as well as FDG. FDG scans were conducted 1 hr after the completion of PET with Met. The color-coded superimposed images of standardized uptake values (SUVs) and transmission data were produced, and the peak SUVs in the lesions were then evaluated. Lesions above 2.5 SUV were interpreted as positive results for active tumor.

RESULTS

The sensitivity of FDG-PET and Met-PET were 64.5% (20/31 lesions) and 61.3% (19/31 lesions), respectively. The mean SUV of FDG in residual or recurrent malignant tumors (n = 31) was significantly higher than that of Met but there was a significant correlation (r = 0.788, p < 0.01) between FDG and Met SUVs in all lesions (n = 34).

CONCLUSION

PET using FDG and Met appear equally effective in detecting residual or recurrent malignant tumors although FDG uptakes were slightly higher than Met uptakes. Both showed a limited diagnostic sensitivity for small (< 1.5 cm) tumors.