Effect of Anagliptin on Vascular Injury in the Femoral Artery of Type 2 Diabetic Rats

Patients with diabetes mellitus (DM) often experience complications such as peripheral arterial disease (PAD), which is thought to be caused by vascular damage resulting from increased oxidative stress. Dipeptidyl peptidase-4 inhibitors have been reported to reduce oxidative stress, although the exact mechanism remains unclear. This study aimed to investigate the impact of long-term (6 weeks) anagliptin treatment at a dose of 200 mg/kg/d against oxidative stress in the femoral artery of Otsuka Long-Evans Tokushima Fatty (OLETF) rats using a well-established animal model for type 2 DM. Serum toxic advanced glycation end-products concentrations and blood glucose levels after glucose loading were significantly elevated in OLETF rats compared to Long-Evans Tokushima Otsuka (LETO) rats but were significantly suppressed by anagliptin administration. Plasma glucagon-like peptide-1 concentrations after glucose loading were significantly increased in anagliptin-treated rats. Superoxide production and reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity in femoral arteries were significantly increased in OLETF rats compared to LETO rats but were significantly decreased by anagliptin administration. The expressions of NADPH oxidase components (p22phox in the intima region and p22phox and gp91phox in the media region) in the femoral artery were significantly increased in OLETF rats compared to LETO rats but were significantly suppressed by anagliptin administration. Furthermore, the femoral artery showed increased wall thickness in OLETF rats compared to LETO rats, but anagliptin administration reduced the thickening. This study suggests that long-term anagliptin administration can reduce oxidative stress in femoral arteries and improve vascular injury.

Effect of Topiroxostat on Reducing Oxidative Stress in the Aorta of Streptozotocin-Induced Diabetic Rats

Xanthine oxidoreductase exists both intracellularly and extracellularly and induces vascular injury by producing reactive oxygen species (ROS). Here, we investigated the effects and mechanism of action of topiroxostat, a xanthine oxidase inhibitor, on ROS using an animal model of type 1 diabetes with persistent hyperglycemia. Six-week-old male Sprague-Dawley rats were administered 50 mg/kg streptozotocin to induce diabetes; at 8 weeks of age, animals were administered topiroxostat (0.3, 1, or 3 mg/kg) for 2 weeks through mixed feeding after which the aorta was sampled. The production of superoxide, a type of ROS, was measured by chemiluminescence and dihydroethidium staining. Cytotoxicity was evaluated by nitrotyrosine staining. Topiroxostat at 3 mg/kg significantly decreased blood urea nitrogen, e-selectin, urinary malondialdehyde, and the urinary albumin/creatinine ratio compared with the streptozotocin group. Superoxide production by xanthine oxidase anchored to the cell membrane was significantly decreased by topiroxostat at both 1 mg/kg and 3 mg/kg compared with the streptozotocin group. Dihydroethidium staining revealed no significant effect of topiroxostat administration on superoxide production. The fluorescence intensity of nitrotyrosine staining was significantly suppressed by 3 mg/kg topiroxostat. Topiroxostat was found to inhibit the production of ROS in the thoracic aorta and suppress vascular endothelial damage. The antioxidant effect of topiroxostat appears to be exerted via the inhibition of anchored xanthine oxidase.

Accumulation of Toxic Advanced Glycation End-Products Induces Cytotoxicity and Inflammation in Hepatocyte-Like Cells Differentiated from Human Induced Pluripotent Stem Cells

Nonalcoholic steatohepatitis (NASH), the aggressive form of the most common chronic liver disease nonalcoholic fatty liver disease, is characterized by inflammation and damage in the liver. Although hepatocyte injury and cell death have been identified as cardinal pathological features of NASH, its pathogenesis has not yet been elucidated in detail. Immortalized cell lines and primary cultured cells have been used as in vitro models of NASH. However, these cells have several disadvantages, such as specialized characteristics by immortalization or limited growth potential. To overcome these difficulties and develop a strategy to analyze the pathology of NASH, we employed hepatocyte-like cells differentiated from human induced pluripotent stem cells (hiPSC-HLCs) as an in vitro model of NASH to clarify the intracellular effects of glyceraldehyde-derived advanced glycation end-products (AGEs), also named toxic AGEs (TAGE). The viability of hiPSC-HLCs decreased with the accumulation of TAGE in the cells, which was consistent with previous findings on human hepatocellular carcinoma cells and human primary cultured hepatocytes. In addition, the TAGE accumulation up-regulated the expression of inflammation-related genes (interleukin 6, interleukin 8, and monocyte chemoattractant protein-1) in hiPSC-HLCs. These results indicated that the accumulation of TAGE induced hiPSC-HLC cytotoxicity and inflammation, which are features of the pathology of NASH. Therefore, we suggest the use of hiPSC-HLCs as an important strategy for analyses of the pathology of NASH.

Intracellular Toxic AGEs (TAGE) Triggers Numerous Types of Cell Damage

The habitual intake of large amounts of sugar, which has been implicated in the onset/progression of lifestyle-related diseases (LSRD), induces the excessive production of glyceraldehyde (GA), an intermediate of sugar metabolism, in neuronal cells, hepatocytes, and cardiomyocytes. Reactions between GA and intracellular proteins produce toxic advanced glycation end-products (toxic AGEs, TAGE), the accumulation of which contributes to various diseases, such as Alzheimer’s disease, non-alcoholic steatohepatitis, and cardiovascular disease. The cellular leakage of TAGE affects the surrounding cells via the receptor for AGEs (RAGE), thereby promoting the onset/progression of LSRD. We demonstrated that the intracellular accumulation of TAGE triggered numerous cellular disorders, and also that TAGE leaked into the extracellular space, thereby increasing extracellular TAGE levels in circulating fluids. Intracellular signaling and the production of reactive oxygen species are affected by extracellular TAGE and RAGE interactions, which, in turn, facilitate the intracellular generation of TAGE, all of which may contribute to the pathological changes observed in LSRD. In this review, we discuss the relationships between intracellular TAGE levels and numerous types of cell damage. The novel concept of the “TAGE theory” is expected to open new perspectives for research into LSRD.

Comparative trial of the effects of continuous locomotion training provided at pharmacies: a pilot study

Background

While the world’s population is growing older, healthy life expectancy is not increasing. The Japanese Orthopedic Association proposed the concept of ‘locomotive syndrome,’ manifested as a decline in mobility functions, and introduced a short test battery for assessing the risk of this syndrome. The test battery includes the ‘stand-up test,’ ‘two-step test,’ and ‘25-question Geriatric Locomotive Function Scale’ (25-question GLFS). The purpose of locomotion training is to improve and sustain standing and gait functions. However, the place where locomotion training can be provided and followed up has not been decided upon. Therefore, a study was conducted to explore the effect of locomotive syndrome improvement by continuous locomotion training provided at community pharmacies. The objective of this study was to evaluate the effect of pharmacists’ instructions and follow-up on the compliance and effectiveness of locomotion training.

Methods

The inclusion criteria were 1) age ≥ 65 years and 2) decline in mobility functions. Guidance on how to perform locomotion training was provided by a pharmacist at the pharmacy. The participants performed locomotion training at home. They were tested and instructed at the pharmacy once a month for 3 months. The main outcome measures were test battery results and the percentage of number of days participants who were able to do the training at home.

Results

Eleven participants were analysed. The minimum implementation percentage was 78%. Improvements were observed in 25-question GLFS, muscle strength, and standing time on one leg. Three participants no longer showed a noticeable decline in mobility function.

Conclusion

Continuous locomotion training provided at pharmacies could contribute to locomotive syndrome prevention.

Trial registration

This study was registered with the University hospital Medical Information Network Clinical Trials Registry (UMIN-CTR; identification No. UMIN000027963. Registered 28 June 2017).

[Improvements in Lifestyle from a Lifestyle Consecutive Self-Review at a Pharmacy]

In 2015, Japan's Ministry of Health, Labour and Welfare released a report on the need for pharmacies to support public health, although the details of such a service was left to each pharmacy. Consequently, pharmacists had to determine the nature of such services. We considered the services that pharmacists could offer to improve people's lifestyles. This study tests such a service at a pharmacy. We prepared a lifestyle self-review test. From September 2015 to February 2016, pharmacists interviewed members of the community using the test, and pharmacists at 50 pharmacies in Aichi prefecture, Japan, set goals for lifestyle improvement. We analyzed 289 tests. The number of people who had a dietary goal concerning snacking was reduced from 19 people who snacked every day to 11. The number of people who had a goal to reduce their drinking was reduced from 7 people who drank every day to 4. The number of people who had an exercise goal was reduced from 17 people who did not exercise every day to 7. The people who had a sleep goal increased the number of days in which they got adequate rest. Those who had specific, tangible goals for walking achieved their goal at a higher rate than did those who had a goal but no tangible elements, such as time spent or number of steps achieved. Overall, the lifestyle self-review at the pharmacy was effective for lifestyle improvement. Pharmacists should help people set goals with tangible elements to improve their lifestyle more effectively.

[Effect of Statins on Glycemic Status and Plasma Adiponectin Concentrations in Patients with Type 2 Diabetes Mellitus and Hypercholesterolemia]

It is reported that statins have inconsistent effects on glycemic status and adiponectin concentrations in patients with type 2 diabetes mellitus (T2DM). We aimed to investigate the effect of statins on these variables in patients with T2DM and hypercholesterolemia. A control group comprising 24 patients with T2DM but without hypercholesterolemia was observed for more than 12 weeks, while 24 patients with T2DM and hypercholesterolemia were treated with statins for the same period (statin group). The percentage changes in the glycemic status [blood glucose and glycated hemoglobin (HbA1c)], and levels of plasma adiponectin [total and high molecular weight (HMW)] were compared between the two groups. The statin group had reduced percentage changes in HbA1c, blood glucose, and total and HMW-adiponectin concentration percentage changes that were similar to those in the control group. However, when matched for sex, age (±5 years) and HbA1c (±0.5%) with the control group, the pravastatin group had reduced percentage changes in the plasma HMW-adiponectin concentrations than the matched controls (p=0.023). However, there were no differences in the percentage changes in the plasma total adiponectin (p=0.137), HbA1c (p=0.202), or blood glucose concentrations (p=0.450) between the two groups. Pravastatin treatment had no effect on the glycemic status of patients with T2DM and hypercholesterolemia, but may reduce the percentage changes in the plasma HMW-adiponectin concentrations. Hence, patients with T2DM and hypercholesterolemia receiving long-term treatment with pravastatin might experience increased insulin resistance.

Role of Glyceraldehyde-Derived AGEs and Mitochondria in Superoxide Production in Femoral Artery of OLETF Rat and Effects of Pravastatin

A complication of diabetes mellitus is the over-production of vascular superoxides, which contribute to the development of arteriosclerosis and peripheral arterial disease (PAD). Hyperglycemia induces the formation and accumulation of advanced glycation end-products (AGEs), which in turn stimulate vascular superoxide production. The mechanism underlying AGE-mediated vascular superoxide production remains to be clarified in lower limb complications associated with diabetes. In the present study, we investigated the role of AGEs and the mitochondrial respiratory complex in superoxide production in femoral arteries using the type 2 diabetes model Otsuka Long-Evans Tokushima Fatty (OLETF) rats [vs. non-diabetic Long-Evans Tokushima Otsuka (LETO) rats]. The effects of in vivo administration of pravastatin on superoxide production in femoral arteries were also examined. Using chemiluminescent assays, luminescence microscopy, and competitive enzyme-linked immunosorbent assay (ELISA), we determined that vascular superoxide production and serum glyceraldehyde-derived AGEs (Glycer-AGEs) increased in OLETF rats. Pravastatin inhibited these responses without changing serum total cholesterol concentrations. The mitochondrial complex II inhibitor thenoyltrifluoroacetone (TTFA) also inhibited vascular superoxide production. Application of Glycer-AGEs in situ increased superoxide production in the vascular wall of femoral arteries from pravastatin-treated OLETF rats, which was then inhibited by TTFA. These results suggest that hyperglycemia increases serum Glycer-AGEs, which subsequently induce superoxide production in the femoral artery of OLETF rats in a mitochondrial complex II-dependent manner. Collectively, our results have partially elucidated the pathological mechanisms leading to diabetes-related PAD, and indicate dual beneficial actions of pravastatin for the prevention of oxidative damage to the vascular wall.

Lifestyle Improvement through Continuous Measurements of Hemoglobin A1c Levels and Lifestyle Checks at the Community Pharmacy in Three Cases

In this study, we took continuous measurements of hemoglobin A1c (HbA1c) levels and conducted lifestyle checks in three cases to determine if these parameters were effective in improving overall wellness. We selected three young men with relatively high HbA1c levels. During the 12-weeks study periods, we regularly measured each participant's HbA1c levels and monitored their lifestyle habits every two weeks at the community pharmacy once every 2 weeks using specific guidelines. The first participant, a 23-year-old man, had a HbA1c level of 5.7% at his first measurement. His HbA1c level decreased to 5.2% at the last measurement. The second participant, a 19-year-old man, had an initial HbA1c level of 5.7% and a final HbA1c level of 5.4%. The third participant was a 22-year-old man with an initial HbA1c level of 5.4%. His HbA1c level had decreased to 5.1% by the last measurement. The lifestyles of all three men improved with respect to exercise and diet. Based on these results, we surmise that continuous measurements of HbA1c and regular lifestyle checks may contribute to reducing the risk of lifestyle-related disease.

[Effects of Training Students through a Program Simulating Medication Administration and Patient Instructions in Pre-training for Practical Training]

Pharmacy school students were trained in a program simulating medication administration and giving adherence instructions. Following the training, the educational effects were evaluated. Students were separated into two groups. One group of students played the role of pharmacists and instructed simulated patients on medication adherence. Another group of students played the role of patients receiving simulated drug therapy; they were instructed on medication adherence by the students playing the role of pharmacists. The educational effects were evaluated using a questionnaire. The scores for "recognition of factors that influence medication adherence" tended to increase after the simulation, and they increased significantly after practical training. The scores for "self-evaluation of technique for instructing patients on medication adherence" increased significantly after the simulation, and they increased even more after practical training. The students' understanding of the effects on patients who were being instructed also increased significantly after the simulation, and these changes were maintained after practical training. In particular, students became more aware of the influence of pharmacists' attitudes. In practical training, the simulation training was helpful for bedside practice at hospital pharmacies and over-the-counter service at community pharmacies. Thus, the use of role play and simulated patients was an effective method for training pharmacy students to instruct patients on medication adherence.

Anaesthetics as cardioprotectants: translatability and mechanism

The pharmacological conditioning of the heart with anaesthetics, such as volatile anaesthetics or opioids, is a phenomenon whereby a transient exposure to an anaesthetic agent protects the heart from the harmful consequences of myocardial ischaemia and reperfusion injury. The cellular and molecular mechanisms of anaesthetic conditioning appear largely to mimic those of ischaemic pre- and post-conditioning. Progress has been made on the understanding of the underlying mechanisms although the order of events and the specific targets of anaesthetics that trigger protection are not always clear. In the laboratory, the protection afforded by certain anaesthetics against cardiac ischaemia and reperfusion injury is powerful and reproducible but this has not necessarily translated into similarly robust clinical benefits. Indeed, clinical studies and meta-analyses delivered variable results when comparing in the laboratory setting protective and non-protective anaesthetics. Reasons for this include underlying conditions such as age, obesity and diabetes. Animal models for disease or ageing, human cardiomyocytes derived from stem cells of patients and further clinical studies are employed to better understand the underlying causes that prevent a more robust protection in patients.

Anaesthetics as cardioprotectants: translatability and mechanism

The pharmacological conditioning of the heart with anaesthetics, such as volatile anaesthetics or opioids, is a phenomenon whereby a transient exposure to an anaesthetic agent protects the heart from the harmful consequences of myocardial ischaemia and reperfusion injury. The cellular and molecular mechanisms of anaesthetic conditioning appear largely to mimic those of ischaemic pre- and post-conditioning. Progress has been made on the understanding of the underlying mechanisms although the order of events and the specific targets of anaesthetics that trigger protection are not always clear. In the laboratory, the protection afforded by certain anaesthetics against cardiac ischaemia and reperfusion injury is powerful and reproducible but this has not necessarily translated into similarly robust clinical benefits. Indeed, clinical studies and meta-analyses delivered variable results when comparing in the laboratory setting protective and non-protective anaesthetics. Reasons for this include underlying conditions such as age, obesity and diabetes. Animal models for disease or ageing, human cardiomyocytes derived from stem cells of patients and further clinical studies are employed to better understand the underlying causes that prevent a more robust protection in patients.

[Educational effects of learning through simulation of diabetes drug therapy]

One of the Specific Behavioral Objectives (SBOs) of pharmaceutical education model-core curriculum is as follows: "Understand patient's state of mind and be sensitive to patient's feelings". We performed learning through simulation of diabetes drug therapy as a means to achieve the objective and evaluated the educational effects of the learning. The simulation was performed and a questionnaire survey was conducted among the 4th-year students of the 6-year curriculum before and after simulation. The score of "level of understanding patient's feelings" was significantly increased after simulation (p<0.001). In addition, the score tended to be associated (R²=0.192) with an increased score in two factors that affect patients' self-care action: "Consciousness of diabetes mellitus" (β=0.251, p=0.062) and "Time and effort for drug therapy" (β=0.248, p=0.065). The main topics of discussion about the simulation included "Lack of sense of critical illness", "Lifestyle", "Dose regimen" and "Necessity of support from patients' family and others close to them". Therefore, the learning through simulation diabetes drug therapy was effective to understand patients' states of mind because students learned the importance of some factors affecting self-care action.

[Clinical evaluation of landiolol hydrochloride, an ultra short-acting beta-blocker]

Postoperative supraventricular tachyarrhythmia (SVT) remains the most common complication of cardiovascular surgery. Current guidelines recommend treatment with beta-blockers in prevention and management of postoperative atrial fibrillation after cardiac surgery. Landiolol hydrochloride is a newly developed ultra short-acting selective beta1-blocker with a half-life of approximately 4 minutes. We investigated its effects on the cardiac function as well as on postoperative SVT. Landiolol hydrochloride had a sufficient therapeutic effect without apparent side effect. After its administration cardiac index decreased, whereas stroke volume increased. Pulmonary artery wedge pressure, pulmonary artery pressure, and central venous pressure remained unchanged. Its main effect proved to be decrease in heart rate.

[Off-pump versus conventional coronary artery bypass grafting in octogenarians]

Coronary artery bypass grafting (CABG) in elderly patients is becoming increasingly common. From January 1996 to February 2002, 836 patients underwent CABG in our hospital, of whom 33 patients (3.9%) were aged 80 years or older. We evaluated the clinical and short-term results of 7 cases of off-pump CABG (OPCAB) and 26 cases of conventional CABG (C-CABG). Mean patient age and preoperative risk factors were similar in both groups. The OPCAB group had significantly decreased operation time (218 versus 281 minutes, p<0.05), and the number of distal anastomoses was significantly fewer in the OPCAB group than in the C-CABG group (1.9 versus 3.8, p<0.05). The frequency of complete revascularization in C-CABG was significantly higher than that of the OPCAB group (84.6% versus 42.9%, p<0.05), and there were no differences in the incidence of major postoperative complications between the groups. There was no hospital death in either group. Cumulative cardiac event free rates were 75% at 1 year and 75% at 3 years in the OPCAB group and 100% at 1 year and 84.6% at 3 years in the C-CABG group (p<0.05). In conclusion, CABG is safe and effective for myocardial revascularization in octogenarians. Except for high-risk cases, complete revascularization with OPCAB or C-CABG should be performed, because favorable outcomes can be expected even in the elderly patients.

Reconstruction of the left ventricle in a patient with cardiac hemangioma at the apex

Cardiac hemangiomas in the left ventricle are extremely rare. A 34-year-old woman, without symptoms, with a diagnosis of cardiac tumor at the apex of the left ventricle was referred to us. The tumor was surgically resected, and the diagnosis was hemangioma. The Jatene technique, originally introduced for left ventricular aneurysmectomy was excellent for repair after resection of a cardiac tumor at the apex.

[Case report of a malfunctioning SJM 19 A aortic valve prosthesis requiring reoperation]

The patient was a 56-year-old female diagnosed with poor lung function who had undergone an aortic valve replacement 10 years ago, receiving an SJM 19 A prosthetic valve. She suffered from dyspnea and chest pain with postural change. Her anticoagulation level was maintained therapeutic. A cinefluoroscopy showed that one of the leaflets in the prosthetic valve was not moving. The aortic peak pressure gradient was calculated to be 68 mmHg using Doppler echocardiography. The patient's clinical condition improved after thrombolytic therapy with urokinase, but a complete normalization of her prosthetic discs was not obtained, so the patient was treated surgically. After an aortotomy, a pannus formation covering the entire SJM 19 A valve was observed. The aortic annulus was estimated to be 16 mm in diameter after the excision of the SJM 19 A valve and required before a larger prosthesis could be inserted. A SJM 19 HP valve was then anchored to the enlarged annulus. Her postoperative course was uneventful. We report a case requiring reoperation after a small aortic mechanical valve prosthesis implanted 10 years previously was damaged by thrombosis and pannus. Pannus formation on small aortic prosthesis easily caused hemodynamic obstructions and mechanical failure. Intensive evaluation with Doppler echocardiography and cinefluoroscopy is required for such patients.

Use of arterial grafts for coronary revascularization. Experience of 2987 anastomoses

OBJECTIVES

The aim of this study was to evaluate the performance and the quality of arterial grafts for coronary artery bypass grafting at The Heart Institute of Japan, Tokyo Women's Medical University.

PATIENTS AND METHODS

From January 1970 to March 1998, 2987 arterial grafts, including left and right internal thoracic arteries, gastroepiploic artery, radial artery and inferior epigastric artery, were used in 1673 patients. In the same period, 1225 saphenous vein grafts were used. Early graft patency was angiographically determined. Also, histological evaluation of operative specimens and preoperative angiographic evaluation of arterial grafts were performed.

RESULTS

The total number of hospital deaths was 38 (2.3%). Of 4212 grafts, 3919 grafts (93%) were evaluated angiographically and 3714 of 3919 grafts were patent (94.8%). The patency rate of internal thoracic artery was better than that of gastroepiploic artery (p < 0.0001), radial artery (p = 0.0005) and saphenous vein grafts (p < 0.0001). However, the patency rate of gastroepiploic artery was better than that of saphenous vein grafts (p = 0.04), while no significant difference was detected between gastroepiploic artery and rdial artery. Only one internal thoracic artery specimen obtained at surgery showed atherosclerotic change, but all gastroepiploic artery specimens had moderate to severe atherosclerotic changes with CD68-positive cell infiltration. Only one patient's left internal thoracic artery out of 200 was not angiographically useable as a conduit, while multiple stenotic lesions in gastroepiploic artery were observed.

CONCLUSIONS

In the graft selection for CABG, the primary choice is internal thoracic artery and the secondary choice is right internal thoracic artery, from the standpoint of histological and angiographic evaluation, gastroepiploic artery and/or radial artery, depending on the target anastomotic site, degree of stenosis, and in situ or free use is the third choice.

Evidence for association between the class I subset of the insulin gene minisatellite (IDDM2 locus) and IDDM in the Japanese population

Although the shortest (class I) minisatellite (i.e., variable number of tandem repeats [VNTR]) alleles in the 5' region of the insulin gene are positively associated with IDDM in Caucasians, the majority of Japanese are homozygous for class I alleles. Here, we determined the exact length, in number of repeat units (RUs), of class I alleles in Japanese subjects. The distribution of class I alleles in Japanese was trimodal, with peaks located at 32/33, 41, and 44 RUs. The shortest component (i.e., 1S [25-38 RUs]) alleles were significantly increased in the IDDM group compared with the control group (54 vs. 46%; P = 0.040). The 1S/1S genotype was significantly increased in the IDDM patients (34 vs. 20%; P = 0.005; relative risk 2.1). Furthermore, the transmission disequilibrium test of Japanese families with 1S/1M or 1S/1L heterozygous parents confirmed the association of 1S alleles; 17 alleles of 1S and 6 alleles of 1M (39-41 RUs) or 1L (42-44 RUs) were transmitted to affected offspring (P = 0.022). In addition, we found tight linkage of 1S with allele 9 of the tyrosine hydroxylase gene microsatellite and allele (-) of the IGF-II gene Apa I polymorphism, but neither 9 nor (-) alleles were significantly associated with IDDM. The present study suggests that a class I subset may have a role in IDDM susceptibility in Japan. It was revealed that the difference between 1S alleles and 1M or 1L alleles is almost consistently characterized by a sequence variation generated by deletion of two copies of an ACAGGGGTCC CGGGG repeat element, implying that sequence variation of class I alleles may influence disease susceptibility.

Significant left ventricular unloading with transaortic catheter venting during venoarterial bypass

Insufficient unloading of the left ventricle with blood stagnation is a main cause of unsuccessful left ventricular (LV) recovery during percutaneous cardiopulmonary support (PCPS). The purpose of this investigation was to evaluate the effectiveness of transaortic catheter venting (TACV) for LV unloading. Six adult mongrel dogs (mean weight 16.3 kg, range 14-20 kg) underwent venoarterial bypass (VAB) with TACV. Bypass flow ranged from 0.8-1.2 L/min, and TACV flow ranged from 160-240 ml/min. In addition to monitoring the standard hemodynamic parameters, the slope of the LV end-systolic pressure-volume relation (Emax) during transient occlusion of the inferior vena cava, the slope of the LV end-systolic pressure-stroke-volume relation (Ea), the stroke work (SW), the LV pressure-volume area (PVA), and the slope of the SW end-diastolic volume relation, the preload recruitable stroke work (PRSW) were assessed by means of a microtip manometer and a conductance catheter. The LV contractility (Emax) and aortic elastance (Ea) were equivalent in the 2 groups with or without TACV (7.7 +/- 1.1 versus 8.4 +/- 1.5 mm Hg/ml and 8.2 +/- 1.4 versus 7.6 +/- 1.3 mm Hg/ml). Comparing the measurements for the baseline to those for VAB with TACV, the SW was significantly reduced, and the PVA/SW was increased by TACV (1,685 +/- 309 versus 867 +/- 188 x 10(-4) J, p < 0.05 and 1.32 +/- 0.03 versus 1.58 +/- 0.11, p < 0.05, respectively). Furthermore, the PRSW was gradually decreased from the baseline value to the value resulting from VAB with TACV (75 +/- 8 versus 44 +/- 3 x 10(-4) J/ml, p < 0.01). In comparison, the percent reduction of SW between VAB and VAB with TACV tended to be increased by TACV (23.2 +/- 7.2% versus 46.9 +/- 7.7%, p = 0.05). These results suggest that TACV might reduce LV work (SW and PRSW) and might increase the LV energetic charge. In conclusion, TACV would be an adjunctive technique to VAB or PCPS for patients with LV failure.

LDL apheresis reduces the susceptibility of LDL to in vitro oxidation in a diabetic patient with hemodialysis treatment

OBJECTIVE

We studied whether LDL apheresis would alter the susceptibility of LDL to in vitro oxidative modification induced by copper ion in a diabetic patient undergoing hemodialysis treatment.

RESEARCH DESIGN AND METHODS

Isolated LDL was dialyzed against phosphate-buffered saline and resuspended at a concentration of 0.3 mg cholesterol mass/ml buffer LDL oxidation was then initiated by addition of 1.66 mumol/l CuSO4, and the formation of conjugated dienes was continuously monitored spectrophotometrically at 234 nm.

RESULTS

The duration of the lag phase of LDL obtained after LDL apheresis was markedly longer than that of LDL obtained before LDL apheresis. The propagation rate and the maximum conjugated diene formation of LDL oxidation were not changed after LDL apheresis.

CONCLUSIONS

A LDL subfraction that was susceptible to oxidation was removed by LDL apheresis, resulting in reduction of susceptibility of LDL to in vitro oxidation remaining in plasma. LDL apheresis may be of clinical importance for preventing atherosclerotic disease in diabetic patients undergoing hemodialysis.

[A case of extra anatomical bypass grafting for coarctation of aorta associated with Turner's syndrome]

A 24-year-old woman with manifestations of Turner's syndrome was referred for detail examinations and treatment of right subclavian tumor on chest X-ray. She was short and obese (147 cm tall and weigh 65 kg). And she had hypertension at upper extremities (160/100 mmHg). Chest enhanced CT revealed right subclavian arterial aneurysm and coarctation of aorta. Aortography showed interrupted descending thoracic aorta with short atretic segment followed by distal descending aorta, aneurysmal collateral artery from right subclavian artery to abdominal aorta and other small collateral arteries. Left lateral thoracotomy was thought to have a high risk for bleeding in the short and obese patient with ample collateral arteries. Therefore, extra anatomical bypass grafting from ascending aorta to abdominal aorta was performed through median sternotomy and laparotomy. After operation recovery was uneventful without residual hypertension. In this report, we discuss about the operation of adult coarctation of aorta and usefulness of extraanatomical bypass grafting.

Clinical implications of renal cyst in primary aldosteronism

The present study surveyed 69 patients with aldosteronoma to study the clinical implications of renal cysts demonstrated in computed tomography. Patients who had cysts (n = 16, 23.2%) were older and had a longer duration of hypertension and more severe hypokalemia than those without cysts (n = 53). Patients with cysts therefore had longer-term, more severe hypokalemia than those without cysts. Endogeneous creatinine clearance (Ccr), measured in 61 patients, was significantly lower in patients with cysts (58.4 +/- 7.1 ml/min, n = 16) than in those without cysts (77.3 +/- 7.1 ml/min, n = 45, P = 0.0039). This significant difference was observed even after adjusting for covariables (age, duration of hypertension, and serum potassium) between the two groups by analysis of covariance (ANCOVA). No significant difference was observed in gender, blood pressure, serum creatinine, plasma aldosterone, or PRA. Age, serum potassium levels, and systolic and diastolic blood pressure were the significant determinants in predicting Ccr in a backward stepwise multiple regression analysis (r = 0.505, n = 61, P = 0.0025). Cysts were graded into four classes on the basis of number and size. Cyst grading correlated negatively with Ccr at a Spearman rank correlation (rho = -0.33, n = 61, P = 0.0103). The incidence of chronic renal failure was significantly higher in patients with cysts (18.8%) than in patients without (0%) in a Fischer's exact probability test (P = 0.0107). Thus, both renal cysts and dysfunction arose and/or developed from common roots, i.e., the duration and severity of hypokalemia, in primary aldosteronism. In addition, we surveyed 27 patients with pheochromocytoma. Patients with renal cysts (n = 8) had a significantly longer duration of hypertension than those without cysts. No significant difference was observed in Ccr between patients with and those without cysts. Thus, a significant link between renal cysts and Ccr was a specific feature of primary aldosteronism, but not of pheochromocytoma. In summary, the renal cysts in primary aldosteronism should be recognized as a significant complication representing the extent of renal injury and dysfunction.

Metformin decreases blood pressure and obesity in OLETF rats via improvement of insulin resistance

To determine whether improvement of insulin resistance decreases blood pressure as well as obesity, metformin (100 mg/kg/d) or vehicle was administered for 20 weeks to 12-week-old male Otsuka Long-Evans Tokushima Fatty (OLETF) rats (n = 10 each), a newly developed animal model of non-insulin-dependent diabetes mellitus (NIDDM) with mild obesity, hyperinsulinemia, and hypertriglyceridemia. Oral administration of metformin ameliorated glucose intolerance and attenuated the insulin response to glucose loading (2 g/kg, i.p.), as evidenced by a decrease in the area under the curve for glucose and insulin at 24 weeks by 19% and 37%, respectively. At 21 weeks, systolic blood pressure was significantly lower in the metformin group than in controls (130 +/- 1.9 vs. 143 +/- 2.7 mmHg, p < 0.01), despite no difference in body weight. Subsequently, blood pressure tended to be slightly but insignificantly lower in the metformin group, and body weight was significantly lower in the metformin group (532 +/- 9.8 vs. 587 +/- 10.3 g at 31 weeks, p < 0.01). Metformin treatment also lowered the level of serum triglycerides (9.4 +/- 0.6 vs. 13.2 +/- 0.5 mmol/l, p < 0.01) and the plasma norepinephrine concentration (4,222 +/- 373 vs. 7,548 +/- 1,058 pg/ml, p < 0.01). These results suggest that metformin-induced improvement of insulin resistance in obese rats with NIDDM may lower blood pressure, as well as decrease sympathetic activity and reduce body weight.

LH and testosterone modulate mercuric chloride-induced acute renal failure in male rats: the implication of stress-induced hypogonadism

The significance of stress-induced hypogonadism remains unclear. Since plasma testosterone and LH have renotropic activity that is other than reproductive, we hypothesize that stress-induced hypogonadism is an adaptive response to protect the kidney. To examine this hypothesis, we prepared hypogonadal male rats with different levels of LH and testosterone through orchiectomy (castration), through chronic treatment with a slowly secreted form of gonadotropin-releasing hormone agonist (GnRHA; GnRHA pretreatment), or through both treatments concomitantly (castration with GnRHA pretreatment). Castrated rats had undetectable plasma testosterone and high plasma LH. GnRHA-pretreated rats had low plasma testosterone and normal plasma LH. Castrated rats with GnRHA pretreatment had undetectable plasma testosterone and normal plasma LH. We compared their sensitivity to HgCl2 nephrotoxicity and found that, when a low dose of HgCl2 (1.5 mg/kg body weight (BW)) was injected s.c. to induce acute renal failure, endogenous creatinine clearance (Ccr) decreased from 390 +/- 30 to 94 +/- 17 ml/h per kg BW in intact (unpretreated) rats. Such a decrease in Ccr was completely prevented in castrated rats (388 +/- 30 ml/h per kg BW) and partially prevented in GnRHA-pretreated rats (216 +/- 40 ml/h per kg BW). When a high dose of HgCl2 (2.25 mg/kg BW) was injected, half of the eight intact rats died but castrated rats and GnRHA-pretreated rats survived (P < 0.05). The elevated resistance in castrated rats was reduced when plasma LH was reduced with GnRHA pretreatment, but was restored by additional pretreatment with ovine LH (40 micrograms/day), as evidenced by changes in Ccr. Elevated resistance in castrated rats was also reduced by the administration of testosterone propionate. In conclusion, hypogonadism activated the preventive and defensive mechanisms that protect the kidney through both decreased plasma testosterone and high or even normal plasma LH.

Characteristics of aldosterone-producing adenoma responsive to upright posture

A small subgroup of primary aldosteronism due to aldosteronoma, named aldosterone-producing renin-responsive adenoma (AP-RA), has been reported to masquerade as idiopathic hyperaldosteronism (IHA) because of the responsiveness of the plasma aldosterone concentration (PAC) to upright posture (UP). We found two patients with AP-RA in 19 patients with aldosteronoma who were examined by UP stimulation and were treated surgically. In 17 patients with typical aldosterone-producing adenoma (APA), PAC decreased or increased only slightly (less than 200% of the basal level); in contrast, it increased to over 300% of the basal level in two patients with AP-RA. The two groups were comparatively studied as to their hormonal levels, adrenal computed tomography (CT) scan and histological findings in order to clarify the characteristics of AP-RA. Basal PAC was within the normal range (11.1 and 13.0 ng/dl) in AP-RA but in APA it ranged from 14.8 to 58.1 ng/dl with a mean of 32.3 +/- 2.7 ng/dl. The diameters of the adenoma in AP-RA were apparently smaller (6 and 9 mm) than those in APA ranged from 10 to 25 mm with a mean of 15.5 +/- 1.1 mm. After a contrast medium was injected at CT scan, the density of the normal adrenal gland adjacent to the adenoma increased but that of the adenoma did not in APA, making a clear distinction between the adenoma and the gland. On the other hand, the density of the adenoma and gland increased to almost the same degree in AP-RA.(ABSTRACT TRUNCATED AT 250 WORDS)

[The experience of mitral valve repair for valve regurgitation]

Between November 1993 and March 1995, 10 patients underwent mitral valve repair. Six of them were performed with McGoon's procedure for prolapsed posterior leaflet. Two of them were performed chodal reconstruction with PTFE sutures for prolapsed anterior leaflet. A patient received McGoon's procedure of posterior leaflet and chodal reconstruction of anterior leaflet. A patient of ischemic mitral regurgitation underwent mitral annuloplasty. There were no operative and late deaths. The MR disappeared or improved to grade I in 9 patients. A patient with McGoon's procedure had hemolytic anemia and required reoperation.

Effects of cysteamine, a somatostatin depleter, on the renin-angiotensin-aldosterone axis and glomerulosa cell growth in rats

Cysteamine, a specific somatostatin depleter, was given to male rats to clarify its role in relation to the renin-angiotensin-aldosterone (RAA) axis and glomerulosa cell growth. Rats received seven daily sc injections of cysteamine at doses of 50 or 150 mg/kg body weight (BW). Their adrenal weights and whole cortical thickness increased, but zona glomerulosa thickness decreased dose-responsively. Plasma renin activity (PRA) and aldosterone concentration (PAC) decreased. Similar results were observed in rats on a low or high salt diet and receiving daily doses of 150 mg/kg BW of cysteamine. In hypophysectomized rats, however, cysteamine given for seven days at daily doses of 100 mg/kg BW did not change either PRA or PAC. Adrenal weight did not change either too. Our results indicate that cysteamine suppresses the RAA axis and glomerulosa cell growth, probably through pituitary factors.

Influence of aminoglycoside antibiotics, streptomycin and kanamycin on histamine secretion in mast cells

Effects of kanamycin and streptomycin on histamine release from rat mast cells were examined in response of the cells to concanavalin A(Con A) plus phosphatidylserine (PS), phytohemagglutinin (PHA) plus PS or a mixture of low-molecular-weight polymers of P-methoxy-N-methylphenethylamine (compound 48/80). In the response to each of the above stimuli, kanamycin (20 mM) or streptomycin (20 mM) caused a decrease in the histamine release elicited in the presence of extracellular Ca2+ (1 mM), although streptomycin showed the much higher inhibitory potency than kanamycin. Similarly, streptomycin was much more effective in suppressing compound 48/80-triggered histamine release in the absence of external Ca2+. Histamine release in the absence of external Ca2+ in the response to the lectin plus PS diminished with increasing concentration of kanamycin, and in this respect streptomycin was much less effective. In the response to the lectin plus PS, external Ca2+ possessed potency to antagonize kanamycin (10 mM)- or streptomycin (10 mM)-caused inhibition of the histamine release, although more markedly the kanamycin-caused one. Streptomycin and kanamycin inhibit histamine release from mast cells challenged with IgE-directed secretagogue or compound 48/80, and the responsible mechanisms seem to implicate the Ca(2+)-antagonistic action on the stimulus-provoked influx of Ca2+ and impairment of the cellular events linked to exocytosis.

Effect of instillation of aldose reductase inhibitor FR74366 on diabetic cataract

The authors investigate the effect of aldose reductase inhibitor FR74366 on diabetic cataract. Streptozocin (STZ)-induced diabetic rats were treated with eye drops of FR74366 (0.03%, 0.1%, and 0.3%) for 16 weeks. Lenses were examined using a slit lamp, and the score of lens opacity was determined on a scale of from 0 (normal lens) to 4 (matured nuclear cataract). Diabetic placebo control rats developed lens opacity linearly, beginning at 3 weeks and reaching a maximum at 8 weeks after STZ injection. Instillation of FR74366 to diabetic rats delayed the cataract formation and inhibited lens sorbitol accumulation in a dose-dependent manner. At 16 weeks after STZ injection, the score of lens opacity was more than 3 (diffuse central opacities) in diabetic placebo control rats, whereas it was less than 2 (peripheral vesicles and cortical opacities) and the lenses remained clear in animals treated with 0.3% of FR74366. Measurement of tissue drug concentrations indicated that FR74366 penetrated into the lens, where its levels were increased in a dose- and time-dependent manner. These three parameters (score of lens opacity and sorbitol and FR74366 levels) were well correlated with each other. Instillation of FR74366 also reduced the sorbitol levels in the retina. However, the sorbitol levels in the sciatic nerve and renal cortex were not changed by instillation of FR74366. Instillation or oral administration of FR74366 has not shown serious side effects in animal toxicity studies. These results suggested that instillation of FR74366 may be a useful therapeutic agent against diabetic cataract and retinopathy.

Characterization of a novel aldose reductase inhibitor, FR74366, and its effects on diabetic cataract and neuropathy in the rat

FR74366 (FK366) ([3-(4-bromo-2-fluorobenzyl)-7-chloro-2,4-dioxo-1,2,3,4- tetrahydroquinazolin-1-yl] acetic acid) is a chemically novel aldose reductase (AR) inhibitor. It exhibited a highly potent, reversible, and mixed type inhibition of partially purified AR from the rat sciatic nerve (IC50 = 3.6 nmol/L) and rat lens (IC50 = 4.4 nmol/L). FR74366 inhibited sorbitol accumulation in the isolated human erythrocyte (IC50 = 1.6 mumol/L), rat lens (IC50 = 39 mumol/L), and rat sciatic nerve (IC50 = 17 mumol/L) incubated with high glucose concentrations. The oral administration of FR74366 to streptozotocin (STZ)-induced diabetic rats for 2 weeks decreased sorbitol levels (ED50 = 3.7 mg/kg for sciatic nerve, 23 mg/kg for lens, 52 mg/kg for retina, and 62 mg/kg for renal cortex). Administration of FR74366 to diabetic rats for 17 weeks delayed cataract formation and admixture of 0.028% FR74366 in the diet completely inhibited the cataract formation. Moreover, the recovery of reduced motor nerve conduction velocity by FR74366 in diabetic rats was demonstrated in prevention and reversal experiments. This recovery effect correlated well with reduction of accumulated sorbitol and fructose levels and normalization of decreased myoinositol levels. The duration and tissue specificity of inhibitory effects of FR74366 on sorbitol accumulation also correlated well with the levels of FR74366 in various tissues of diabetic rats. These data indicate that both decreases in tissue sorbitol levels and improvement of functional defects reflect FR74366 levels in tissue rather than plasma in diabetic rats. These results, taken together, suggest that FR74366, which is currently undergoing clinical trials in Japan and the United States, will be a useful therapeutic agent for diabetic complications.