Impact of diabetes and glycaemic control on peripheral artery disease in Japanese patients with end-stage renal disease: long-term follow-up study from the beginning of haemodialysis.

AIMS/HYPOTHESIS: End-stage renal disease (ESRD) patients with diabetes have been regarded as being at the highest risk of cardiovascular disease. We therefore investigated the relationship between diabetes and the incidence of peripheral artery disease (PAD) in new haemodialysis patients. METHODS: We enrolled 1,513 ESRD patients who had just begun haemodialysis therapy. They were divided into two groups: those with (n = 739) and those without diabetes (n = 774). The endpoint was the development of PAD, defined as ankle brachial pressure index ≤ 0.9 or toe brachial pressure index <0.7 in patients with an ankle brachial pressure index >0.9. RESULTS: According to the Kaplan-Meier method, the 10 year event-free rate for development of PAD and lower limb amputation was significantly lower in the diabetes group than in the non-diabetes group (60.3% vs 82.8%, HR 2.99, 95% CI 2.27, 3.92, p<0.0001 and 93.9% vs 98.9%, HR 5.59, 95% CI 2.14, 14.7, p = .0005 for PAD and lower limb amputation, respectively). In patients with diabetes, quartile analysis of HbA1c levels showed that the highest quartile group (≥ 6.8% [51 mmol/mol]) had significant development of PAD and lower limb amputation compared with lower quartile groups (PAD HR 1.63, 95% CI 1.17, 2.28, p = .0038; lower limb amputation HR 2.99, 95% CI 1.17, 7.70, p = .023). CONCLUSIONS/INTERPRETATION: Diabetes was a strong predictor of PAD after initiation of haemodialysis therapy in patients with ESRD. In addition, higher HbA1c levels were associated with increased risk of developing PAD and requiring limb amputation in such diabetic populations.

Peierls mechanism of the metal-insulator transition in ferromagnetic hollandite K2Cr8O16.

Synchrotron x-ray diffraction experiment shows that the metal-insulator transition occurring in a ferromagnetic state of a hollandite K(2)Cr(8)O(16) is accompanied by a structural distortion from the tetragonal I4/m to monoclinic P112(1)/a phase with a √2×√2×1 supercell. Detailed electronic structure calculations demonstrate that the metal-insulator transition is caused by a Peierls instability in the quasi-one-dimensional column structure made of four coupled Cr-O chains running in the c direction, leading to the formation of tetramers of Cr ions below the transition temperature. This provides a rare example of the Peierls transition of fully spin-polarized electron systems.

Development of a high-efficiency high-resolution particle-induced x-ray emission system for chemical state analysis of environmental samples.

We have developed a high-efficiency high-resolution particle-induced x-ray emission (PIXE) system employing a von Hamos-type crystal spectrometer for a chemical state identification of trace elements in environmental samples. The energy resolution of the system was determined to be about 0.05% through the observation of Si Kalpha(1,2) x rays (1.74 keV) from elemental silicon. The throughput efficiency of the system was also evaluated quasitheoretically to be 1.6x10(-7) counts/incident proton for Si Kalpha(1,2) emission. To demonstrate a chemical state analysis using the high-resolution PIXE system, Si Kalpha(1,2) and Kbeta x-ray spectra for SiC, Si(3)N(4), and SiO(2) were measured and compared. The observed chemical shifts of the Si Kalpha(1,2) peaks for SiC, Si(3)N(4), and SiO(2) relative to elemental silicon were 0.20, 0.40, and 0.55 eV, respectively. The tendency of these shifts were well explained by the effective charges of the silicon atoms calculated by a molecular orbital method.

Transradial approach for diagnostic selective cerebral angiography: results of a consecutive series of 166 cases.

BACKGROUND AND PURPOSE: Diagnostic selective cerebral angiography is commonly performed via transfemoral and transbrachial approaches. With these approaches, however, patients occasionally suffer serious complications. The purpose of this study was to evaluate the feasibility, efficacy, and safety of a transradial approach as an alternative to the transfemoral and transbrachial approaches. METHODS: Between October 1998 and September 1999, transradial cerebral angiography was performed in 166 consecutive patients in a single center as a diagnostic procedure. Before the procedure, we confirmed the collateral blood supply to the hand from the ulnar artery using a modified Allen test. Regular catheterization techniques were practiced using our newly designed 120-cm-long 4F catheter. In 42 patients, anticoagulant and/or antiplatelet therapy was given perioperatively. RESULTS: Twelve of the 166 patients proved to be poor candidates for the transradial approach, owing to restlessness (n = 9), lack of collateral blood supply via the ulnar artery (n = 2), and brachial artery stenosis (n = 1). The radial artery was successfully punctured and cannulated in the remaining 154 patients. Selective catheterization of the intended vessels was obtained in all carotid and vertebral angiographic procedures with no major vascular complications. CONCLUSION: Compared with transfemoral and transbrachial approaches, the transradial approach is a less invasive and safer technique for selective cerebral angiography and may warrant consideration as a standard procedure. Anticoagulant or antiplatelet therapy need not be discontinued for this method.

Intraoperative regional and functional thermography during resection of cerebral arteriovenous malformation.

We present the first use of intraoperative thermographical imaging for the surgical resection of a cerebral arteriovenous malformation. For obtaining intraoperative regional and functional thermographical images, a real-time mode infrared camera was installed to an operating microscope with an exclusively developed attachment device. Changes of the surface temperature of the cortical draining vein and the surrounding cortical surface were observed intraoperatively before and after the occlusion of the main feeder. Intraoperative functional thermography with cold physiological saline solution demonstrated a change in the heat clearance of the draining vein after complete obliteration of the feeder.

Transradial approach for selective cerebral angiography: technical note.

Selective cerebral angiography is currently being performed using transfemoral and transbrachial approaches. However, these techniques require patients to tolerate a prolonged focal compression and sometimes cause serious complications such as pulmonary embolism. The authors describe a technique of transradial approach as a safer selective cerebral angiography. Between July 1997 and November 1998, 70 patients underwent selective cerebral angiography with a transradial approach using a 4-F catheter. The collateral blood supply to the hand from the ulnar artery was confirmed using Allen's test prior to the procedure. To prevent the mechanical spasm of the radial artery, an arterial introducer 20 cm long was used. The radial artery was successfully punctured and cannulated in all patients. Selective catheterization of the intended vessels was obtained in over 98% of the carotid angiography and over 95% of the vertebral angiography. No major vascular complications such as cerebral infarction, upper limb ischemia, significant local hematoma or pseudoaneurysm were experienced. The transradial approach is a less invasive and safer technique for selective cerebral angiography, and could be an alternative to transfemoral and transbrachial approaches.

Surgical approaches to the anterior communicating artery aneurysm and their results.

In the past 12 years, 102 cases of anterior communicating artery aneurysm have been operated upon in our institution. Two basic microsurgical approaches (pterional and interhemispheric) were used. The combined pterional and interhemispheric approach was performed in a few cases. The rational for each surgical approach is discussed in relation to anatomical factors such as the height of the aneurysm neck, the side of dominance of A1, the relationship between the bilateral proximal parts of A2s, and the projection of the aneurysm. The final outcome was correlated to the preoperative clinical grading and timing of surgery. The overall results were as follows; 82.4% good, 5.9% fair, 4.9% poor, and 6.8% mortality rate. The operative results for pterional and interhemispheric approach were comparable with each other. In the combined approach, we got poorer results which could be related to excessive brain retraction and unfavourable clinical grading.

Surgical treatment of hemodialysis-related shoulder arthropathy.

Thirteen patients with hemodialysis-related shoulder arthropathy were treated either with arthroscopic synovectomy or with open surgery. Arthroscopic synovectomy was performed in eight patients who had shoulder pain, shoulder immobility or both but did not have cystic bone lesions. The therapy was effective for pain relief and improvement of shoulder function for six months but in 12 months the shoulder pain reappeared in most of the patients. Open surgery was done in 5 patients who, in addition to shoulder pain and immobility, had humeral head bone cysts. Resection of the deposited mass on the biceps tendon sheath, of hypertrophied synovium and bursa as well as curettage of cysts and calcium hydroxyapatite ceramic implantation were performed. The therapy was effective for pain relief throughout the follow-up period (12 months). No adverse effects were noted for either procedure. Resected specimens of the synovia contained amyloid as indicated by a positive Congo-red stain by light microscopy and the presence of amyloid fibrils by electron microscopy. Deposition of amyloid in the biceps tendon sheath, synovium and bursa and invasion of the humeral head by amyloid were observed upon open surgery. The results suggest that the resection of deposited material induces the improvement of the shoulder arthropathy.

Stenotic lesions in vascular access: treatment with transluminal angioplasty using high-pressure balloons.

In our institute, one hundred sixty-four balloon dilatations of stenotic lesions in vascular access have been performed since November 1991. All of these procedures were done with high-pressure balloon catheters. In addition to seventy-four cases treated with only percutaneous transluminal angioplasty, there were thirty-four cases which were treated by thrombectomy and/or surgical revision with subsequent intraoperative balloon angioplasty. These angioplastic procedures were initially successful in 142 (87%) of 164 stenoses. The patency rate after 3 months was 68%; after 6 months, 42%; and after 1 year, 25%. There were no serious adverse reactions in our series. This procedure can be safely done with minimal traumatization and, although long-term patency rates are low, repeated dilatations can be performed with ease, when restenosis occurs, to keep a fistula functioning for a long time in appropriate patients.

Effect of artificial carbon dioxide foot bathing on critical limb ischemia (Fontaine IV) in peripheral arterial disease patients.

BACKGROUND: It has been reported that artificial carbon dioxide (CO(2)) foot bathing improves subcutaneous microcirculation in peripheral arterial disease (PAD) patients. However, the effect for critical limb ischemia (CLI) with ulceration or gangrene (Fontaine stage IV) is not identified. The physiological effects of CO(2) bathing and the outcome of limb salvage in such patients were studied. METHODS: In 18 healthy volunteers (Study I), the dorsal pedis peripheral blood flow was measured by a laser Doppler flow-meter during CO(2) foot bathing (1000 ppm, 37 degrees C) for 10 min. A Holter electrocardiogram was also recording in the same period. Blood flow and cell volume significantly increased during bathing. Eighty-three CLI limbs (Fontaine IV) in 68 PAD patients (Study II) underwent artificial CO(2) foot bathing (for 10 minutes twice daily >2 months) were followed up >6 months. RESULTS: In Study I, analysis of heart rate variability showed that high frequency amplitude (HFA) considerably increased and the ratio of low frequency amplitude to HFA (LF/HF) noticeably decreased during bathing. In Study II, 69 limbs (83.1%) could be salvaged. Twenty-seven of 28 limbs (96.4%) which have ulcer and gangrene in only one toe, 13/16 limbs (81.2%) in multiple toes and 29/39 limbs (74.4%) in all toes and/or heel respectively were saved. CONCLUSIONS: The effect of CO(2) enriched water on the subcutaneous microcirculation might be brought about by peripheral vasodilation reflected by increased parasympathetic and decreased sympathetic activity, and the artificial CO(2) foot bathing is clinically effective on salvage of CLI (Fontaine stage IV) limbs.

A classification of juxta-dural ring aneurysms with reference to surgical anatomy.

We report a subgroup of internal carotid artery (ICA) aneurysms located near the carotid ring which we call juxtadural ring aneurysms. These aneurysms are classified into three types: paraclinoid intradural, carotid cave and infraclinoid extradural aneurysms. The paraclinoid intradural aneurysms arise from the ICA distal to the origin of the ophthalmic artery and are close to the dural ring, which may include some so-called carotid-ophthalmic aneurysms. The carotid cave aneurysms are located in the carotid cave which is seated in the infraclinoid carotid groove and proximal to the origin of the ophthalmic artery. They are located at the angiographical genu and in the intradural space anatomically. The infraclinoid extradural aneurysms are located close to the dural ring extradurally in the infraclinoid carotid groove sinus, a peripheral venous space of the cavernous sinus. The infraclinoid extradural aneurysms should be differentiated from aneurysms in the cavernous sinus, because they are located in the infraclinoid carotid groove sinus.

[A case of disproportionately large communicating fourth ventricle (DLCFV) combined with syringomyelia and Chiari malformation].

We report a rare case of disproportionately large communicating fourth ventricle (DLCFV) combined with syringomyelia and Chiari malformation. The case was a 27-year-old male who underwent ventriculoperitoneal (V-P) shunt on the right side for hydrocephalus caused by traumatic intracerebral and intraventricular hemorrhage. One month later, he became somnolent with posterior fossa symptoms (nausea, vomiting and nystagmus). CT scan demonstrated enlarged fourth ventricle, which was diagnosed as DLCFV because the ventriculogram revealed patency of the aqueduct. One and half month later a second V-P shunt was made on the left side to increase the shunt flow. He became ambulatory with a cane, although the fourth ventricle remained moderately dilated on CT scan. Two months after the additional V-P shunt, he slipped and hit the occiput and immediately became tetraparetic. The patient was treated conservatively under the diagnosis of central spinal cord injury. The MRI taken 2 months after the accident revealed Chiari malformation (type 1), syringomyelia and a dilated fourth ventricle which was compressing the brainstem. After the fourth ventriculoperitoneal (FV-P) shunt, the tetraparesis transiently improved but then again worsened. On the CT scan the syrinx did non change in size, while the size of the fourth ventricle became normal. After syringoperitoneal (S-P) shunt the patient showed a moderate improvement of tetraparesis. Unfortunately he suffered appendicitis complicated with peritonitis and all the shunts were immediately changed to external drainage. However, the patient developed meningitis and became paraplegic. The motor function of the upper extremities slightly improved by aspiration of fluid via the external drainage system from the syrinx.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cerebellar hemangioblastoma developing after nephrectomy for renal cell carcinoma].

Cerebellar hemangioblastomas are known to be occasionally associated with abdominal tumors such as renal cyst and renal cell carcinoma. But most of the abdominal tumors reported are clinically silent and usually diagnosed after the hemangioblastomas have been found in the central nervous system. We report a rare case in which a renal cell carcinoma preceeded in its onset of symptoms 4 years to a cerebellar hemangioblastoma. A 56-year-old female underwent left nephrectomy because of a left renal cell carcinoma at the age of 49. About 4 years after the nephrectomy, she developed signs and symptoms of intracranial hypertension and was operated on for a cerebellar tumor which was histologically diagnosed as hemangioblastoma. Her family history was non-contributory. Four years later, recurrence of the cerebellar tumor was found on the CT scan and abdominal studies were negative except for a suspected parapelvic cyst in the right kidney on abdominal ultrasonography. Subtotal removal of the cerebellar hemangioblastoma was performed followed by irradiation.

[Evaluation of a method to determine the myocardial uptake from 123I-BMIPP myocardial SPECT and its significance].

We examined methods of calculating myocardial uptake (TU) of 123I-BMIPP by SPECT, and compared TU to heart function (ejection fraction (EF), cardiac output (CO), cardiac index (CI)) calculated by left ventriculography. Forty-two patients with acute myocardial infarction were classified into 5 groups; within 1 week (I), from 1 to 2 weeks (II), from 2 weeks to 1.5 months (III), from 1.5 to 3 months (IV) and more than 3 months (V) after percutaneous transluminal coronary angioplasty (PTCA). Chest depth (Tw) was calculated by measuring the thoracic absorption rate of 123I. In calculating TU, the myocardial count was calculated from short-axis tomograms, and then absorption was corrected using Tw to calculate each value on early-phase image (E) and delay-phase image (D). The influence of lung uptake on myocardial count was only 1.76%. When TU was compared to heart function, there were correlations between group I and group V. Especially in group V D-TU was a significantly correlated with heart function. In heart function CI, but not EF nor CO, was significantly correlated with TU. It was suggested that the correlation between TU and heart function reflected the infarct condition before PTCA in group I, and that the individual difference in recovery of fatty acid metabolism in group V. The significant correlation between D-TU and CI suggests that D-TU reflects heart function and fatty acid metabolism, although TU is influenced by differences in physical status.

Effects of high-dose vitamin B6 therapy on microcytic and hypochromic anemia in hemodialysis patients.

In an attempt to treat hemodialysis patients suffering from microscopic and hypochromic anemia (MHA) and who are either sufficient or deficient in serum ferritin level, we investigated the effects of oral administration of vitamin B6 (VB6). Twenty-six patients with MHA undergoing long-term stable hemodialysis treatment were divided into three groups. There was no significant difference in the serum VB6 levels in these patients as compared with normal subjects before the study. Patients in group I, whose serum ferritin levels were normal, were orally administered 180mg of VB6 every day for 20 weeks. Patients in groups II and III, whose serum ferritin levels were far below normal (due to suspected iron deficiency anemia), were either administered iron alone (intravenous administration of 40mg of iron for 12 consecutive dialysis treatments, for 4 weeks--group II) or both iron and VB6 (group III). There was significant improvement in the hematocrit, mean corpsular volume (MCV), and mean corpsular hemoglobin (MCH) in group I patients supporting the contention that this group of patients had pyridoxine responsive anemia (PRA). The number of sideroblasts in bone marrow in these patients, however, was significantly low when compared to that of the normal subjects. In addition, the combined therapy with iron and VB6 led to the longer-sustained improvement in hematocrit in patients with suspected iron deficiency anemia (group III) when compared to those treated with iron alone (group II).(ABSTRACT TRUNCATED AT 250 WORDS)

Brain natriuretic peptide detects cardiac abnormalities in mass screening.

BACKGROUND: Plasma brain natriuretic peptide (BNP) is elevated in asymptomatic patients with various cardiac abnormalities. We tested the hypothesis that measuring BNP is useful for detecting asymptomatic patients with cardiac abnormalities who are not identified by conventional health check-up programmes. MATERIALS AND METHODS: From 2001 to 2002, 6189 subjects (women 34.0%; mean age 56.6 years) underwent multiphasic health check-ups in our hospital, of which 4818 without cardiac abnormalities as revealed by the health check-up were enrolled in the present study. Their plasma concentrations of BNP were measured. RESULTS: Plasma concentrations of BNP were higher than the normal reference upper limit of our hospital (21.3 pg mL(-1)) in 925 of the 4818 subjects. Echocardiography was performed in 471 subjects who were randomly selected from the 925 subjects with elevated BNP. Abnormal findings were detected in 174 subjects, comprising valvular heart disease in 83, systolic dysfunction in 10, diastolic dysfunction in 54, left ventricular hypertrophy in 41, left ventricular enlargement in 11, left atrial enlargement in 13 and paroxysmal atrial fibrillation in 3. CONCLUSIONS: Since BNP measurement identifies additional subjects with cardiac abnormalities, it is useful for detecting asymptomatic cardiac abnormalities among apparently healthy subjects, and is suitable for use in high-quality mass screening.