A transfer-function representation for the input-output relation in consecutive Michaelis-Menten-type reactions

A transfer-function representation is devised to describe analytically and approximately the reaction velocity (output) in response to the substrate influx rate (input) in single and two consecutive Michaelis-Menten-type reactions in an open and homogeneous system. The transfer function for single reactions has an expression of first-order system, the time constant of which is dependent on the kinetic parameters and flow rate (steady-state value of the input and output), but independent of the magnitude of the input change. The transfer function for the two-reaction system can be formed with successive multiplication of the transfer functions for the first and second reactions. The validity of the representation is examined with variation in the kinetic parameters and flow rate by comparing the output of the transfer function with the actual response obtained from the computer simulation, that is, numerical integration of the rate equation. The analysis of the indicial responses indicates that the transfer functions for single and two consecutive reactions are valid within a certain error for the response around a steady state.

CNS regulation of blood lactate concentration in anesthetized rats

This study evaluated the effect of stimulating the central nervous system (CNS) with neostigmine, an inhibitor of acetylcholinesterase, on the blood lactate concentration in fed rats and in rats fasted for 48 hours. After the rat was anesthetized with pentobarbital, neostigmine was stereotaxically injected into the third cerebral ventricle. In fed rats, the central injection of neostigmine significantly increased the blood lactate level, while concomitantly increasing plasma glucagon, epinephrine and norepinephrine concentrations. Constant infusion of somatostatin throughout the experiments, to inhibit glucagon secretion from the pancreas, did not affect alterations in blood lactate by central injection of neostigmine. In adreno-medullated rats, CNS-stimulation by neostigmine still increased plasma norepinephrine significantly, however, the alteration in blood lactate was only one-third of that in intact rats. Intraperitoneal propranolol, but not phentolamine, prevented the rise in lactate. Neostigmine increased lactate in fasted rats as well as in fed rats. We conclude that in anesthetized rats, stimulation of the CNS by neostigmine increases blood lactate mainly through circulating epinephrine and partially through circulating norepinephrine or direct sympathetic nervous stimulation; glucagon does not appear to be involved in the increase in blood lactate.

Sequential change of the hypervariable region of the hepatitis C virus genome in acute infection

Hepatitis C virus (HCV) infection is characterized by persistence of liver inflammation that often leads to end-stage liver disease, although the mechanisms are not fully understood. A hypervariable region (HVR) has been reported in the E2/NS1 region of the HCV genome, in which striking diversity is found among different HCV isolates. To investigate the association of the HVR alterations with the clinical courses of HCV infection, a longitudinal analysis of the HVR in patients with acute HCV infection was carried out. Plasma samples were obtained at several times in three patients with acute hepatitis C. Plasma RNA was extracted and reverse transcribed, and DNA fragments that included the HVR were amplified by PCR. The sequences of the HVR were directly determined from the PCR products by the dideoxy chain termination method, from which amino acid sequences were deduced. In all cases, plasma HCV-RNA disappeared with the improvement of the initial alanine aminotransferase (ALT) elevation, but HCV-RNA reappeared about 1 year later with or without deterioration of the hepatitis. In a case of sporadic acute hepatitis, the HCV in the recurrent phase had seven amino acid substitutions in the HVR compared with that in the acute phase, although no amino acid changes were noted during the initial acute phase. In a case of posttransfusion hepatitis, a marked difference was observed between the acute and the recurrent phases, with an amino acid homology of 30% (8/27). The mutation rate of the HVR had a tendency to accelerate as the HCV infection progressed to the chronic stage.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship of ultrasonographic findings to histology in prostate cancer

We compared ultrasonic findings and histology in 25 patients with prostate cancer. Ultrasonically guided transperineal biopsy of focal prostatic lesions was performed in 19 patients, in whom prostate cancer was suspected. Six of them had two different echogenic areas in the same focal lesion, so a total of 25 echogenic areas were assessed. Fourteen of these 25 areas were hypoechoic. The Gleason score varied, but residual prostatic glands and cancer glands with slightly enlarged lumen did not exist. Six of the areas were slightly more echogenic than the above 14 areas, and cribriform cancer with slightly enlarged glands occupied the greater part of these specimens. Four of the areas were isoechoic, and they contained residual prostatic glands showing a normal distribution, regardless of the Gleason score or grade of tumor infiltration. The only hyperechoic lesion contained numerous tiny areas of calcification. In the 6 patients without focal lesions, the peripheral and transition zones showed a normal echogenicity. Two of these patients had cancer in the transition zone, and biopsy showed tumor glands with slightly enlarged lumens. In the 4 patients, various-sized tumors were seen, but there was a normal distribution of residual prostatic glands and stroma. These results indicated that prostatic echogenicity is determined by the presence of tumor glands with enlarged lumina as well as residual prostatic glands and stroma.

Activation of central GABAA receptors suppresses the alteration of plasma catecholamine levels induced by neostigmine or histamine in rats

We investigated the effects of intraventricular injection of muscimol, the GABAA receptor agonist, on the alteration of plasma epinephrine (E) and norepinephrine (NE) levels induced by neostigmine or histamine in anesthetized rats. Injection of neostigmine (10 nmol) into the third cerebral ventricle increased plasma levels of E more than NE, while histamine (500 nmol) increased plasma levels of NE more than E. Concomitant injection of muscimol (2.5 nmol) with neostigmine or histamine significantly suppressed the alteration of E and NE levels induced by neostigmine or histamine. These findings suggest that activation of central cholinergic neuron stimulates the adrenal medullary response more than the sympathetic nervous system, while activation of central histaminergic neuron stimulates the sympathetic nervous system more than the adrenal medullary response in anesthetized rats. Activation of GABAA receptors in the CNS suppresses these effects.

Effects of diabetes on cardiac glycogen metabolism in rats

The effects of diabetes on myocardial glycogen metabolism in rats were examined and compared with those of fasting. Male Wistar rats were divided into three groups: controls, streptozotocin-induced diabetics, and one-week fasted. Isolated rat hearts were subjected to substrate-free 30-min Langendorff perfusion followed by 60-min working heart perfusion with glucose alone or in combination with insulin or insulin plus beta-hydroxybutyrate (BHB). Myocardial glycogen contents were determined before or 30 min after Langendorff perfusion, or 60 min after working heart perfusion. Before Langendorff perfusion, tissue glycogen concentrations in control, diabetic, and fasted hearts were 3.3 +/- 0.2, 10.0 +/- 0.9, and 5.7 +/- 0.5 (mg/g wet weight), respectively. In diabetic rats, the myocardial glycogen concentration was markedly decreased after working heart perfusion of any of the substrate combinations, even those with insulin and BHB. In contrast, myocardial glycogen in control or fasted rats was not reduced after the addition of glucose with insulin, and/or glucose with insulin and BHB. These results suggest that degradation of tissue glycogen occurs in isolated perfused hearts from diabetic rats, while a clearly different response is shown by fasted hearts.

Pharmacokinetic study of recombinant human erythropoietin treatment in pre-dialysis end stage renal disease patients

We treated pre-dialysis ESRD patients with recombinant human erythropoietin (rHuEPO) by either the subcutaneous (s.c.) or intravenous (i.v.) route, and investigated the pharmacokinetics of rHuEPO. Twenty patients were divided equally into two groups by the difference in route, and rHuEPO was administered once per week for 8 weeks. The dose was 3,000 and 6,000 IU in the s.c. group and 3,000, 6,000 and 9,000 IU in the i.v. group. Although anemia was corrected significantly in both groups, residual renal function was not affected significantly. Pharmacokinetic study revealed that none of the parameters changed between the initial and final treatments in any of the groups. Area under the curve (AUC) and maximum concentration (Cmax) was consistently smaller in the s.c. --than in the i.v.--treated group. Mean residence time (MRT) was 3 times longer in the s.c. group than in the i.v. group. Bioavailability of rHuEPO in the s.c. group was around 35%, and mean absorption time (MAT) was around 25 hours. Though the s.c. route has been reported to be more effective for correcting anemia with rHuEPO than the i.v. route when rHuEPO was administered either twice or three times per week, our study demonstrated that the effect of rHuEPO was almost equal between the s.c.-treated and i.v.-treated groups when rHuEPO was administered once per week. We assume that this equivalent degree of efficacy in the s.c. group in spite of low values of AUC and Cmax might be derived by the longer MRT. Thus, we consider that MRT is an important factor and the efficacy of rHuEPO should be investigated with evaluation of MRT when the administration route is different.

Effects of high glucose concentrations and epalrestat on sorbitol and myo-inositol metabolism in cultured rabbit aortic smooth muscle cells

To clarify the relationship between abnormality of sorbitol and/or myo-inositol metabolism caused by hyperglycemia and diabetic macroangiopathy, we investigated the effects of high glucose concentrations and epalrestat, an aldose reductase inhibitor, on the metabolism of sorbitol and myo-inositol in cultured rabbit aortic smooth muscle cells. In cells incubated in the presence of 30 mM glucose for 72 h, the sorbitol content increased approximately 4.5-fold, and the myo-inositol level decreased by 55% compared with control values. Kinetic analysis of high-affinity myo-inositol uptake suggested that smooth muscle cells exposed to high glucose concentrations exhibited a noncompetitive type of inhibition characterized by ouabain-sensitive, energy-dependent active transport. Epalrestat blocked glucose-induced changes in sorbitol and myo-inositol metabolism, suggesting that these changes were caused by the accumulation of sorbitol in the cells. These metabolic changes may impair function of smooth muscle cells, contributing to the pathology of diabetic atherosclerosis, especially Mönckeberg's calcific medial sclerosis. The use of an aldose reductase inhibitor may prevent these glucose-induced changes.

The egg nucleus regulates the behavior of sperm nuclei as well as cycling of MPF in physiologically polyspermic newt eggs

The possible role of the egg nucleus in regulating the behavior of sperm nuclei and the cycling of maturation-promoting factor (MPF) was investigated in the physiologically polyspermic eggs of the newt Cynops pyrrhogaster. Many sperm entered all areas of the egg, but only one sperm pronucleus, the principal sperm pronucleus, moved to the center of the animal hemisphere to form a zygote nucleus with the egg pronucleus. All sperm and egg pronuclei synthesized DNA, but the zygote nucleus completed the synthesis of DNA 0.5-1 hr earlier than the accessory sperm nuclei. Entrance into M phase by the accessory sperm nuclei was delayed to a greater and greater extent with increasing distance of these nuclei from the zygote nucleus. When DNA in the egg nucleus was damaged by uv irradiation, not only were both prophase and M phase in the zygote nucleus prolonged, but also the MPF cycle was delayed. Some accessory sperm nuclei in the animal hemisphere escaped degeneration to form additional bipolar spindles, so that delayed multipolar cleavage occurred. The MPF activity in the vegetal hemisphere was less than 25% of that found in the animal hemisphere at M phase in normally fertilized eggs. The levels of immunologically detectable proteins that contained the sequence PSTAIR in vegetal hemispheres were less than 25% of those in animal hemispheres. These results indicate that the egg nucleus of the Cynops egg is involved in the control of the activation of MPF and that the accessory sperm nuclei in the vegetal hemisphere degenerate as a result of the lack of components that are indispensable for entry into M phase.

Biguanides may produce hypoglycemic action in isolated rat hepatocytes through their effects on L-alanine transport

We investigated the mechanisms of the effects of the biguanides metformin and buformin on hepatic gluconeogenesis in hepatocytes isolated from normal rats. Both 10 nM glucagon and 50 microM dibutyryl cAMP increased [3H]alanine uptake in isolated hepatocytes of normal rats by about 150% and 55%, respectively, compared with the effect of 5 mM alanine alone. Metformin (3 mM) reduced glucagon-stimulated [3H]alanine uptake to the level seen with alanine alone; buformin (3 mM) inhibited glucagon-stimulated [3H]alanine uptake by about 69%. The effects of biguanides on dibutyryl cAMP-stimulated [3H]alanine uptake were similar, but of smaller magnitude compared with those observed in the presence of glucagon. Ouabain (3 mM) had a stronger inhibitory effect on [3H]alanine uptake than the biguanides. However, 3 mM tolbutamide failed to suppress [3H]alanine uptake in the presence or absence of glucagon or dibutyryl cAMP. Our results suggest that the inhibition of alanine uptake, related to a reduction in the Na+/L-alanine transport system, is a possible mechanism of biguanide-related inhibition of hepatic gluconeogenesis.

Effects of glimepiride on in vivo insulin action in normal and diabetic rats

To evaluate the effects of glimepiride on insulin action in peripheral tissues, we investigated insulin-induced glucose uptake in normal and diabetic rats using the euglycemic clamp procedure (insulin infusion rates: 6 and 30 mU/kg/min). Normal rats: After oral administration of glimepiride (0.1 mg/kg/day; NG) or saline (NC) for 2 weeks, euglycemic clamp procedures were performed. During submaximal hyperinsulinemia (620 +/- 35 pmol/l, mean +/- S.E.M.), metabolic clearance rates of glucose (MCR) in NG were significantly higher than in NC (25.1 +/- 2.1 vs. 18.3 +/- 1.2 ml/kg/min, P < 0.05). During maximal hyperinsulinemia (5235 +/- 270 pmol/l), MCRs in NG were higher than in NC, but there was no statistical significance (43.3 +/- 2.8 and 38.9 +/- 2.8). Diabetic rats: streptozotocin-induced diabetic rats were divided into four groups, GI (glimepiride treatment, 0.1 mg/kg/day p.o., with insulin, 5 U/day s.c.), SI (insulin alone), SG (glimepiride alone), and SC (saline). MCRs in the four groups were similar during 6 mU/kg/min clamps. During 30 mU/kg/min clamps, MCRs in GI were significantly higher than those in SC, SG or SI (23.4 +/- 2.8 vs. 12.2 +/- 1.9 and 8.9 +/- 0.8, P < 0.01, and vs. 17.4 +/- 1.5, P < 0.05). Although MCRs in SI tended to be higher than in SC, there was no significant statistical difference between these two groups. These results suggest that glimepiride enhances insulin action in peripheral tissues, and that glimepiride treatment with insulin improves the insulin resistance observed in streptozotocin-induced diabetic rats.

Cypridina luciferin analog reduces the incidence of ischemia/reperfusion-induced ventricular fibrillation

A Cypridina luciferin analog (CLA), considered to be a sensitive and specific agent for the assay of superoxide, was assessed in isolated hearts for its effects on ischemia/reperfusion injury. Hearts of anesthetized male Wistar rats were isolated and perfused with a modified Krebs-Henseleit bicarbonate buffer to serve as non-recirculating working heart preparations. After 15 min of perfusion to achieve stability, they underwent 20 min of global ischemia and were then reperfused for 30 min with or without 250 microM of CLA, dissolved in the perfusate. The incidence of ventricular fibrillation was only 13% in the CLA group, whereas it was 88% in the controls. The CLA treatment was further associated with significantly increased left ventricular developed pressure and cardiac output; and in contrast, the left ventricular end-diastolic pressure was significantly reduced, as compared with the control group. Thiobarbiturate reacting substance content in the hearts of the CLA group was significantly decreased (27.5 +/- 2.4 versus 36.9 +/- 9.7 mumol/g dry weight). This study thus indicates that CLA may be useful for alleviating ischemia/reperfusion injury (reperfusion-induced arrhythmia and damage to heart function) involving free radicals.

Effects of diabetes on lipid peroxidation and scavenger activity in ischemia/reperfusion injury

This study examined the effects of ischemia/reperfusion on cardiac function and diabetes-associated lipid peroxidation and scavenger induction in isolated working hearts. Cardiac function in diabetic rats was depressed in proportion to the duration of diabetes. Plasma levels of malondialdehyde (MDA) were increased significantly after diabetes of 1-week duration (1wD). MDA levels in the myocardium were increased significantly after 4-weeks (4wD) and tissue superoxide dismutase (SOD) activity was also elevated significantly in 8-week diabetic rats (8wD) as compared to control values. In both controls and diabetics, tissue MDA concentrations increased significantly during the first 3 min of reperfusion following 20 min of ischemia, compared with preischemia levels. At the end of reperfusion, tissue MDA levels decreased in controls and 1wD hearts, but remained elevated in the 4wD and 8wD cases. The SOD activity in 8wD hearts decreased significantly after 20 min of global ischemia followed by 30 min reperfusion, compared with preischemia levels. By contrast, there were no significant differences between preischemic and after-reperfusion data for parameters of cardiac function in 8wD rats. Thus, lipid peroxidation appears to have little influence on cardiac function during ischemia/reperfusion in rats with chronic diabetes.

Development of the Overlapping Oligonucleotide Database and its application to signal sequence search of the human genome

We have developed ODS (Overlapping Oligonucleotide Database for Signal Sequence Search)--the first relational database that integrates information on biological features into the search for signal sequences. In existing biological sequence databases, even relational ones, retrieving nucleotide sequences based on their biological features involves much labour and time or even the development of a new program. GenBank sequence data, including FEATURES records, are organized into three relational tables in ODS. Nucleotide sequences are transformed into overlapping oligonucleotides in order to facilitate the signal sequence search rapidly without the need for specific alignment programs. This transformation leads to a one-to-one correspondence between the nucleotide sequence and its biological feature. The signal sequence search by ODS is done in SQL queries and ODS obviates the need for molecular biologists to write computer programs. The application of ODS to searches of promoter regions revealed putative cis-acting elements and basic statistical analyses of occurrences of oligonucleotides showed interesting findings concerning the 'cg' dinucleotide.

[Carbohydrate metabolism]

This review summarizes progress in glycosylation research of relevance to atherosclerosis. Glucose reacts in vivo with cellular proteins nonenzymatically and forms Amadori products. The Amadori products proceed very slowly to undergo a number of further dehydration and rearrangement to form advanced glycosylation end products (AGE). The AGE moiety are characterized by being brown, fluorescent chromophores that can cross-rink proteins. In contrast Amadori products, AGE are irreversible and accumulate on long-lived proteins (eg, collagen, enzyme, lens crystallins) for many years. AGE proteins can modify lipoproteins fibrinogen, collagen and DNA. AGE protein receptor is identified on macrophages. AGE may accelerate development of atherosclerosis by various manner.

Glomerular localization of thrombomodulin in human glomerulonephritis

BACKGROUND

Thrombomodulin (TM), a glycoprotein expressed on the surface of endothelial cells, transforms protein C into a potent anticoagulant by binding thrombin. TM may be an important regulator of intraglomerular coagulation because functional TM activity was demonstrated in glomeruli isolated from normal human and rat kidneys. The role of TM in glomerulonephritis is unknown.

EXPERIMENTAL DESIGN

Sections from 4 normal human kidneys and from kidneys of 100 patients with various forms of glomerulonephritis were studied by light and transmission electron microscopy, and by light and electron immunohistochemical techniques using polyclonal antibodies to recombinant human TM, and monoclonal antibodies to the membrane attack complex of the complement system. The expression of TM was graded from 0 to 4 according to the intensity and extent of the distribution, and the results were compared with the clinicopathologic findings.

RESULTS

In normal glomeruli and in glomeruli with minimal abnormalities, a small amount of TM was localized at the vascular pole only (grade 0-1). In membranoproliferative glomerulonephritis and lupus glomerulonephritis, the amount of TM found on the plasma membrane of endothelial cells was significantly increased (grades 2 to 4). The expression of TM was directly correlated with proteinuria (p < 0.001), glomerular hypercellularity (p < 0.01), and number of subendothelial immune deposits (p < 0.01). In contrast, in other forms of glomerular diseases, TM was not increased and no correlation was found with the clinicopathologic parameters.

CONCLUSIONS

In membranoproliferative glomerulonephritis and lupus glomerulonephritis, the amount of TM expressed by the plasma membranes of glomerular endothelial cells is increased, and this finding is a marker of disease activity. The significance of an increased expression of an endothelial anticoagulant glycoprotein in diseases characterized by pathologic intraglomerular coagulation is unknown, and requires further studies.

Protective actions of YM737, a new glutathione analog, against cerebral ischemia in rats

Effects of YM737[N-(N-r-L-glutamyl-L-cysteinyl)glycine 1-isopropyl ester sulfate monohydrate], a new glutathione (GSH) analog more readily transported into cells than GSH, on cerebral ischemia were compared with those of GSH and some other drugs in rats subjected to occlusion of the bilateral carotid arteries. YM737 significantly reduced lethality, increased brain-water levels as measured by both dry-wet and NMR methods, and increased malondialdehyde (MDA) levels in the cerebral ischemic rats. On the other hand, pharmacological actions of GSH itself was less than those of YM737. In the ischemic rats used in the present study, there was no significant difference in 31P-NMR signals between the normal and the cerebral ischemic rats. These results suggest that YM737 showed anti-cerebral ischemic effects presumably due, in part, to inhibition of lipid peroxidative responses.

Expression of the hepatocyte growth factor receptor in the regenerating rat liver

The c-met oncogene product is a cell-surface receptor, which ligand is believed to be the hepatocyte growth factor. We studied the expression of c-met oncogene in the regenerating rat liver after either partial hepatectomy or CCl4-induced liver injury. Northern blot analysis showed that after partial hepatectomy the transcripts of c-met decreased at 8 h, reached the minimum at 36 h, and returned to the steady level on the seventh day. In contrast with the hepatectomized liver, the transcripts of c-met increased after CCl4 treatment. These observations suggest that c-met transcription may be regulated differently depending on regeneration signals.

Effects of prolonged application of isoprenaline on intracellular free magnesium concentration in isolated heart of rat

1. The effect of prolonged application of isoprenaline on intracellular free-Mg2+ concentration ([Mg2+]i) was examined by use of 31P-nuclear magnetic resonance (31P-n.m.r.) in rat isolated hearts. Left ventricular pressure (LVP) was simultaneously measured. 2. [Mg2+]i was estimated from the separation of the alpha- and beta-ATP peaks, using the dissociation constant of MgATP 38 microM (established previously). In normal (phosphate-free, Krebs-Henseleit) solution, [Mg2+]i was approximately 0.4 mM. 3. When isoprenaline was applied for 100 min, a transient increase in [Mg2+]i was observed during the initial 25 min, whilst concentrations of ATP ([ATP]) and phosphocreatine ([PCr]) decreased and [Pi] correspondingly increased. During the subsequent 75 min of isoprenaline application, [Mg2+]i decreased below its resting levels. Washout of isoprenaline restored [Mg2+]i and [PCr], but [ATP] remained low. These changes elicited by isoprenaline were not observed in the presence of propranolol, a typical alpha-adrenoceptor blocker. 4. Isoprenaline increased both LVP and heart rate. The increased LVP and heart rate slowly returned to lower values during prolonged application of isoprenaline, but remained higher than those before application. 5. The transient rise in [Mg2+]i elicited by isoprenaline could be attributed to the decrease in [ATP] resulting in a release of Mg2+. The subsequent decrease in [Mg2+]i during the prolonged applications suggests that beta-adrenoceptor stimulation itself facilitates Mg(2+)-extruding mechanism(s).

The effect of acarbose on blood glucose profiles of type 2 diabetic patients receiving insulin therapy

Nine patients with Type 2 diabetes receiving insulin therapy were treated with acarbose 100 mg thrice daily for 1 week to investigate the effect of acarbose on blood glucose control. Daily blood glucose profiles contained fewer excursions during acarbose administration and low levels were maintained. The M-value, an indicator of blood glucose fluctuation, decreased significantly from a run-in period value of 37.6 +/- 8.7 (SEM) to 16.7 +/- 4.0 during the acarbose period (p < 0.05) and rose again to 28.9 +/- 6.7 (p > or = 0.05) in the follow-up period. The 24-h urinary glucose excretion similarly decreased during acarbose administration. As expected, no decrease in HbA1C was observed due to the short treatment period. The 24-h urinary C-peptide excretions and serum lipids were not influenced by acarbose therapy. Frequent episodes of clinical hypoglycaemia were experienced while on acarbose therapy, indicating a decrease in insulin requirements. Adverse events such as flatulence and abdominal distention were observed in six out of nine cases. Symptoms were generally mild and well tolerated, only one patient dropped out because of diarrhoea and abdominal pain. We conclude that acarbose could usefully be administered to Type 2 diabetic patients treated with insulin to improve blood glucose control and reduce insulin requirement if the appropriate selection criteria were met.

Circadian blood pressure variation in diabetic patients with autonomic neuropathy

OBJECTIVE

To elucidate distinctive patterns of circadian variation of blood pressure in diabetic patients.

DESIGN

Circadian variations and indices of blood pressure variability were examined by non-invasive ambulatory blood pressure monitoring. The indices were assessed for a correlation with various possible signs of autonomic neuropathy, including the coefficient of variation of the RR interval and orthostatic hypotension.

METHODS

The study was conducted on 38 normotensive diabetics and 15 age- and sex-matched non-diabetic controls, all of whom were outpatients at the Third Department of Internal Medicine in Nagoya University Hospital. Ambulatory blood pressure measurements were taken in all subjects and the coefficients of variation in the RR interval and postural changes in blood pressure were determined.

RESULTS

The diabetic patients demonstrated a different pattern of circadian variation in blood pressure from that of the non-diabetics. Diurnal-nocturnal differences were significantly smaller in diabetics than in non-diabetic controls. Statistically significant correlations were found between diurnal-nocturnal differences in blood pressure and the duration of diabetes, glycaemic control, the coefficient of variation in the RR interval and the change in blood pressure on standing. A subgroup of diabetic patients with severe autonomic neuropathy showed the lowest diurnal-nocturnal differences.

CONCLUSIONS

In diabetic patients with autonomic neuropathy circadian variations in blood pressure are blunted. Ambulatory blood pressure monitoring can detect these abnormal variations and therefore may be useful in evaluating diabetic autonomic neuropathy.

Are diabetic hearts more resistant to ischemia/reperfusion injury?

The present study was designed to investigate the cardiac impairment during ischemia/reperfusion injury in rats with streptozotocin-induced diabetes vs controls. Male rats were divided into three groups: controls, one-week diabetic rats (1wDM) and four-week diabetic rats (4wDM). In the isolated working heart, left ventricular developed pressure (LVDP), left ventricular end-diastolic pressure (LVEDP), and maximum positive and negative dP/dt were measured before ischemia and after 20 min of global ischemia followed by 30 min reperfusion. In the pre-ischemic state, hearts of 4wDM showed a significant (p < 0.05) depression of the maximum positive and negative dP/dt compared with those of controls and 1wDM. There were no significant differences in LVDP and LVEDP among the three groups. The incidence of reperfusion-induced ventricular fibrillation (VF) was 75% for controls, 15% for 1wDM rats, and 27% for 4wDM rats. In hearts without reperfusion-induced VF, there were no differences in the three groups, between the pre- and post-ischemic values in LVDP, LVEDP, and maximum positive and negative dP/dt. These findings suggest that diabetic hearts exhibit no susceptibility to ischemia/reperfusion injury.

[A case of advanced gastric cancer responding to an FAP (5-FU, ADM, platinum compounds) combined chemotherapy]

An experience with an advanced gastric cancer patient with metastases to bilateral breasts, uterus, abdominal lymph nodes, bilateral axillary and supraclavicular lymph nodes, and bone marrow, responded extremely well to an FAP combined chemotherapy as reported here. The patients received four courses of 5-FU (370 mg/m2/day, for five days, continuous infusion), ADM (30 mg/m2 on day 1, i.v.) and CDDP (55 mg/m2 on day 1, i.v.) every 3 weeks in our hospital. This was followed by 7 months of outpatient therapy with 5-FU (550 mg/m2 on day 1, i.v.), ADM (30 mg/m2 on day 1, i.v.) and CBDCA (330 mg/m2 on day 1, i.v.) for every 4 weeks. The complete remission of the primary and metastatic lesions, that was confirmed by the histological examinations, was obtained after 10 months since the initial treatment started. The toxicity was generally moderate, however, the alopecia was severe. The patient has been living for 6 months without any signs of the recurrence after the complete remission obtained.