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Objective: Large-bore aspiration catheters (ACs) are used successfully in mechanical thrombectomy (MT). However, tortuous access routes prevent device navigation because of the ledge effect. The AXS Offset Delivery Assist Catheter is designed to reduce the ledge effect. The purpose of this study was to evaluate whether the Offset affects AC navigation compared with standard inner microcatheters in MT., Methods: We retrospectively investigated 75 MTs for anterior circulation occlusion between January 2018 and May 2022 at our hospital. All MTs were performed using an AC, and 2 types of inner microcatheter (Offset or 0.021-0.027-inch standard microcatheter) were chosen randomly during AC navigation. The patients' characteristics, MT techniques, angiographic findings, and clinical outcomes were compared between the Offset and standard group (Non-Offset). The puncture to first pass of the lesion time was investigated to compare the characteristics of the inner catheters., Results: The Offset group comprised 12 patients versus 63 in the Non-Offset group. Although most baseline clinical characteristics and outcomes were similar between the groups, the puncture to first pass of the lesion time was significantly shorter in the Offset versus Non-Offset group (31 ± 10 vs. 46 ± 24 minutes, respectively; P = 0.032). In the Offset group, all stent retrievers were deployed via the Offset. One artery dissection and 8 symptomatic intracranial hemorrhages occurred in the Non-Offset group; no complications occurred in the Offset group., Conclusions: The AXS Offset delivery assist catheter permitted faster and safer navigation of various ACs to the occlusions compared with standard delivery microcatheters in MT., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: Detailed vasculature of vertebral artery dissecting aneurysms (VADAs) is often complicated owing to the irregular structure with the intimal flap/double lumen. Our aim was to present an endovascular reconstructive technique with assessment of detailed vasculature and the relationship between dissection and surrounding vessels using cone-beam computed tomography angiography (CBCT-A)., Methods: The study included 6 cases with complex vertebral artery dissecting aneurysm. Selective digital subtraction angiography initially identified the location and shape of dissection. CBCT-A was then performed with selective injection into the affected vertebral artery. Luminal morphology of the dissection and surrounding arterial anatomy were assessed using CBCT-A., Results: CBCT-A clearly demonstrated luminal morphology of the intimal flap/double lumen, the entrance into the pseudolumen, and the entire dissecting segment. Tiny perforator arteries were also identified. In all 6 cases, target coil embolization for the pseudolumen and stent placement using an LVIS stent for the entire dissecting segment were successfully performed with the aid of information obtained from CBCT-A. No complications occurred in the perioperative period, and improvement of dissection was identified in the follow-up period., Conclusions: Target embolization of complex vertebral artery dissecting aneurysm with endovascular reconstructive technique with special reference to the detailed anatomy of dissection using CBCT-A would be useful for safe and effective treatment results., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: Chronic total occlusion (CTO) of femoropopliteal artery (FP) continues to be a lesion subset where maintaining long-term patency after endovascular treatment is challenging. We evaluated the efficacy of cutting balloon angioplasty (CBA) for de novo FP-CTOs in patients with symptomatic lower limb ischemia., Methods: Seventy-three limbs of 67 symptomatic patients with de novo FP-CTOs successfully recanalized using CBA alone were enrolled in this study. Primary patency was defined as the absence of recurrent symptoms and no deterioration of the ankle-brachial index (ABI) >0.10 from the immediate postinterventional value., Results: The mean age was 73.5 ± 7.3 years, and 59.7% of patients had diabetes mellitus. Most lesions were classified as Trans-Atlantic Inter-Society Consensus II type C (n = 18; 24.7%) or type D (n = 44; 60.3%), with mean lesion and occluded lengths of 24.8 ± 11.4 and 17.8 ± 11.2 cm, respectively. No procedure-related adverse events occurred, except one distal embolization. The ABI significantly increased after intervention from 0.52 ± 0.12 to 0.80 ± 0.15 (P < 0.0001), with marked improvement in clinical symptoms (Rutherford stage: 2.7 ± 1.0 to 1.1 ± 1.2, P < 0.0001). The mean follow-up period was 31.2 ± 18.0 months, and the primary patency rates at 12 and 24 months were 75.3% and 60.6%, respectively. The independent predictive factors of failed patency were baseline hemoglobin A1c (P = 0.031, hazard radio [HR] 1.51 per 1%), occluded length ≥15 cm (P = 0.036, HR 2.90), and severe dissection (P = 0.033, HR 2.85). Vessel calcification and diameter did not affect primary patency., Conclusions: CBA is a feasible option for endovascular treatment of FP-CTOs. Diabetic status, occlusion length, and severe dissection after CBA are independent negative predictors of long-term patency., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Functional mitral regurgitation (MR) can occur in patients with atrial fibrillation (AF) despite having preserved left ventricular (LV) systolic function. This MR is known as atrial functional MR. The aim of this study was to clarify the mechanism of atrial functional MR using real-time three-dimensional transesophageal echocardiography (3DTEE)., Methods: Sixty patients underwent transthoracic echocardiography and 3DTEE: 16 patients with AF and significant non-organic MR and preserved LV ejection fraction (>50%) constituted the AF-MR group, 20 patients with AF and no significant MR formed the AF-NSMR group, and 24 normal subjects comprised the control group., Results: The left atrial volume index was significantly larger in the AF-MR group (95±41ml/m 2 ) than in the AF-NSMR group (38±13ml/m 2 , p<0.05) or the control group (21±7ml/m 2 , p<0.05). The 3D annular circumference was significantly longer in the AF-MR group than in the AF-NSMR group. The annular-anterior leaflet coaptation angle was smaller in the AF-MR group than in the AF-NSMR group (11±6° vs. 18±9°, p<0.05). The annular-posterior leaflet coaptation angle was comparable between the two AF groups (26±12° vs. 28±10°), whereas the annular-posterior leaflet tip angle was larger in the AF-MR group than in the AF-NSMR group (59±13° vs. 44±11°, p<0.05). The posterior leaflet bending toward LV cavity was therefore significantly larger in the AF-MR group than in the AF-NSMR group (32±10° vs. 18±15°, p<0.05)., Conclusions: In patients with AF and significant functional MR occurring despite their preserved LV systolic function, the left atrium and mitral annulus were dilated and the anterior leaflet was flattened along the mitral annular plane, whereas the posterior leaflet was bent toward the LV cavity., (Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Background: Symptomatic extensive spinal extradural meningeal cyst (SEMC) developing after traumatic brachial plexus injury (TBPI) is rare. We discuss the mechanism of extensive SEMC development, surgical strategies, and preventive measures against SEMC after TBPI., Case Description: A 58-year-old man with TBPI 16 years previously developed spastic paraparesis of the lower limbs, sensory disturbance below the periumbilical level, and dysfunction of bladder and bowel over 2 years. The patient couldn't walk and was wheelchair bound. Magnetic resonance imaging (MRI) revealed an extensive multilocular extradural cyst posterior to the spinal cord ranging from the C4 to Th6 level, associated with severe spinal cord compression. On constructive interference in steady-state MRI, the cyst was divided, with many septa, and extended to the root sleeves. During the operation, transdural communication sites of cerebrospinal fluid (CSF) into the cyst were revealed at C5/6, C6/7, and C7/Th1 levels around the nerve root sleeves. Treatment involved unroofing of the cyst wall and closure of the transdural CSF communication without cyst removal. Autologous muscle pieces were placed over the defect to close the transdural communication. Two weeks postoperatively, MRI showed decreased cyst size and reduced spinal cord compression, and the patient could walk without support. It was thought that the patient's daily lifting of heavy weights at work and an excessive exercise regimen increased CSF pressure and cyst size after TBPI., Conclusion: For patients with TBPI, it is necessary to prevent greater CSF pressure and to perform long-term follow-up MRI after injury., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Kaposi sarcoma and primary effusion lymphoma cells are infected with Kaposi sarcoma-associated herpesvirus (KSHV), predominantly in the latent form, and KSHV replication is observed rarely. Angiogenesis plays a crucial role in the pathogenesis of both Kaposi sarcoma and primary effusion lymphoma. In this study, we found that fumagillin, a potent angiogenesis inhibitor, induced replication of KSHV in primary effusion lymphoma cell lines. The transcript and protein product of replication transcriptional activator (RTA) were induced by 1-10 μM fumagillin at 24 and 48 h, respectively. Western blot analysis demonstrated that 10 μM fumagillin induced not only RTA expression but also other KSHV-encoded lytic proteins. A real-time PCR array detecting KSHV gene expression demonstrated that the expression profiles of KSHV induced by fumagillin were similar to those induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), but the amounts of each transcript were lower than those induced by TPA. Finally, real-time PCR demonstrated an increase in that viral DNA copy number per cell in fumagillin-stimulated primary effusion lymphoma cell lines, indicating replication of KSHV. In addition to TPA, 10 μM fumagillin resulted in growth inhibition of primary effusion lymphoma cell lines. These observations suggest that an angiogenesis inhibitor is an agent with potent effects on cell growth and KSHV reactivation in primary effusion lymphoma cells., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: The features of intrinsic ganglionated plexi (GP) in both atria after extensive pulmonary vein isolation (PVI) and their clinical implications have not been clarified in patients with atrial fibrillation (AF)., Objective: The purpose of this study was to assess the features of GP response after extensive PVI and to evaluate the relationship between GP responses and subsequent AF episodes., Methods: The study population consisted of 216 consecutive AF patients (104 persistent AF) who underwent an initial ablation. We searched for the GP sites in both atria after an extensive PVI., Results: GP responses were determined in 186 of 216 patients (85.6%). In the left atrium, GP responses were observed around the right inferior GP in 116 of 216 patients (53.7%) and around the left inferior GP in 57 of 216 (26.4%). In the right atrium, GP responses were observed around the posteroseptal area: inside the CS in 64 of 216 patients (29.6%), at the CS ostium in 150 of 216 (69.4%), and in the lower right atrium in 45 of 216 (20.8%). The presence of a positive GP response was an independent risk factor for AF recurrence (hazard ratio 4.04, confidence interval 1.48-11.0) in patients with paroxysmal, but not persistent, AF. The incidence of recurrent atrial tachyarrhythmias in patients with paroxysmal AF with a positive GP response was 51% vs 8% in those without a GP response (P = .002)., Conclusion: The presence of GP responses after extensive PVI was significantly associated with increased AF recurrence after ablation in patients with paroxysmal AF., (Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: The mechanism of persistent atrial fibrillation (AF) is multifactorial, and arrhythmogenic foci (AMF) might be involved in the occurrence of persistent AF. In this study, we examined the electrophysiological features of AMF during and immediately after ablation, and evaluated the relationship between the presence and number of residual AMF on the risk of AF recurrence after a vigorous sinus rhythm restoration ablation in patients with long-standing persistent AF., Methods: The study consisted of 117 consecutive patients with persistent AF who underwent catheter ablation (CA). We performed direct cardioversion to restore sinus rhythm before the pulmonary vein (PV) isolation and at the end of the CA. Then we evaluated the features of the AMF inducible with isoproterenol and the pacing-based AF inducibility., Results: After the completion of ablation, AF could still be induced in 37 of 117 patients (31.6%). Spontaneous PV AMF during CA were observed in 104 of 117 patients (91%), and non-PV AMF in 63 of 117 (54%). Residual non-PV AMF were significantly associated with the pacing-based AF inducibility and an enlarged left atrial volume. In the multivariate analysis, the AF duration (1.01 [range, 1.00-1.02] months; P = 0.012), left atrial volume (1.01 [range, 1.01-1.02] mm; P = 0.006), and residual AMF (3.95 [range, 1.32-11.8] yes, no; P = 0.004) were independent risk factors for recurrent AF., Conclusions: Residual AMF are associated with an increased long-term AF recurrence after sinus rhythm restoration ablation for long-standing persistent AF., (Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

The standard approach for carotid endarterectomy cannot provide adequate exposure of the distal internal carotid artery in the presence of high cervical carotid bifurcation or high plaque. Limited accessibility of the distal internal carotid artery has resulted in the development of various operative techniques. Mandibular subluxation is the most simple and least invasive technique, but it does require invasive maneuvers, such as wiring, to stabilize the mandible. We use a mouthpiece made by the dentist to stabilize the mandible in the physiologic subluxated position. This technique provides an adequate exposure of the distal internal carotid artery as with the other methods, and the risk of morbidity is very low., (Copyright © 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Amyloid beta protein (A beta) accumulates in the brains of aging humans, amyloid precursor protein (APP) transgenic mouse lines, and rhesus monkeys. We tested the hypothesis that aging was associated with increased activity of the beta-site amyloid precursor protein cleaving enzyme (beta-secretase, BACE) in brain. We evaluated BACE activity, BACE protein, and formic acid-extractable A beta levels in cohorts of young (4 months old) and old (14 to 18 months old) nontransgenic mice (n = 16) and Tg2576 APP transgenic mice (n = 17), young (4.4 to 12.7 years old) and old (20.9 to 30.4 years old) rhesus monkeys (n = 17), and a wide age range (18 to 92 years old) of nondemented human brains (n = 25). Aging was associated with increased brain A beta levels in each cohort. Furthermore BACE activity increased significantly with age in mouse, monkey, and human brains, independent of brain region. BACE protein levels, however, were unchanged with age. BACE activity correlated with formic acid-extractable A beta levels in transgenic mouse, nontransgenic mouse, and human cortex, but not in monkey brain. These data suggest that an age-related increase of BACE activity contributes to the increased production and accumulation of brain A beta, and potentially predisposes to Alzheimer's disease in humans.

PqqC/D was purified from Escherichia coli transformant. The purified enzyme converted an intermediate that accumulated in a pqqC mutant of Methylobacterium extorquens AM1 to PQQ. The reaction did not show any dependence of NAD(P)H that was observed in the crude extract before purification. PqqC/D reacted with the intermediate stoichiometrically, but not catalytically. When partially purified proteins from the crude extract of E. coli were added to the reaction mixture, the rate of PQQ production increased dependent on the amount of NADPH added and the total amount of PQQ produced increased.

We investigated the levels and locations of angiotensin II-forming enzymes, angiotensin converting enzyme (ACE) and chymase, in aneurysmal and normal aortas. Aneurysmal aortic specimens (n = 14) were obtained at the time of operative aneurysm repair from 14 patients ranging in age from 57 to 84 y. Normal aortic specimens (n = 16) were obtained from 16 patients (48 to 72 y) who underwent coronary artery bypass surgery. The ACE and chymase activities were determined using each specimen. Sections of each specimen were immunostained with antibodies for ACE and chymase. The ACE activities in the aneurysmal and normal aortas were 0.82 +/- 0.10 and 0.14 +/- 0.05 mU/mg protein, respectively, and this difference was significant. The chymase activities in the aneurysmal and normal aortas were 17.9 +/- 2.40 and 1.02 +/- 0.18 mU/mg protein, respectively, and this difference was also significant. In the aneurysmal aorta, ACE-positive cells were detected with macrophages in the intima and media and chymase-positive cells were detected with mast cells in the media and adventitia, whereas positive ACE and chymase cells in the normal aorta were located only in the endothelium and adventitia, respectively. Angiotensin II-forming enzymes, chymase and ACE, were significantly increased in the aneurysmal aorta, and increased angiotensin II may be associated with the development of aneurysmal formations.

The C-terminal domain of p53 may bind single-stranded (ss) DNA ends and catalyze renaturation of ss complementary DNA molecules, suggesting a possible direct role for p53 in DNA repair (Proc. Natl. Acad. Sci. USA, 92, 9455-9459, 1995). We found that DU-86, a duocarmycin derivative which alkylates DNA, bound ssDNA and enhanced the DNA binding activity of the p53 C-terminus. DU-86 weakened p53-mediated catalysis of complementary ssDNA renaturation. p53 C-terminus catalyzed DNA strand transfer toward annealing between intact ssDNAs and toward eliminating DU-86-damaged ssDNA from duplex formation. These results suggest that p53, via the C-terminal domain, may play a direct role in DNA repair by preferential recognization and elimination of damaged DNA.

The contribution of the 5'-flanking sequence of the human gamma-glutamylcysteine synthetase heavy subunit (gamma-GCSh) gene to cisplatin-induced transcriptional up-regulation was studied using various human growth hormone reporter constructs which were transfected to a human lung cancer cell line SBC-3. Cisplatin at the concentration of 3 microM increased the transcriptional activity of the longest sequence from -1,413 to +91 bp of the gamma-GCSh gene to 246% of that in non-exposed cells. The distal sequence from -1,413 to -193 bp was shown to negatively regulate transcriptional activity in both cisplatin-exposed and non-exposed cells using deletion and thymidine kinase (TK) promoter-linked constructs. Cisplatin increased the transcriptional activity of the proximal GC-rich sequence from -192 to +91 bp to 340%, of which magnitude was the maximum among deletion constructs. A deletion from -108 to -28 bp, or +34 to +91 bp significantly decreased cisplatin-induced increases in transcriptional activity from 258 to 105%, or 340 to 160%, respectively. When the sequence from -108 to -22 bp, or +26 to +91 bp was linked to the heterologous TK promoter, cisplatin increased the transcriptional activity to 171 or 181%, respectively, from that of 128 or 137%, respectively, in non-exposed cells. These findings indicate that the proximal sequence from -192 to +91 bp of the gamma-GCSh gene, especially from -108 to -28 bp, and +34 to +91 bp, is involved in cisplatin-induced transcriptional up-regulation in SBC-3 cells.

Transcriptional activity of the 5'-flanking sequence of the human gamma-glutamylcysteine synthetase heavy subunit (gamma-GCSh) gene was investigated in COS7 cells transfected with hGH reporter constructs having successively deleted 5'-flanking sequence of the gamma-GCSh gene. Transcriptional activity was determined by the amounts of hGH secreted from the reporter constructs. Deletion of the sequence from -1,413 to -664 or -315 base pairs (bp) increased transcriptional activity from 100 to 138 or 136%. Further deletion from -315 to -241 bp, which contained an AP1 site, decreased transcriptional activity to 87%. Mutations introduced into the AP1 decreased transcriptional activity from 136 to 105%. These findings suggested that the AP1 increased transcriptional activity. When the sequence from -241 to -192 bp was deleted, transcriptional activity was restored from 87 to 128%. When this sequence was linked to the thymidine kinase promoter, it also decreased transcriptional activity by 38%. Deletion from -192 to -149, -116, or -108 bp did not significantly alter transcriptional activity. Further deletion of the GC-rich sequences from -108 to -70 and -28 bp dramatically decreased transcriptional activity from 135 to 87 and 34%, respectively. These findings indicate that multiple DNA elements, especially those in the proximal GC-rich sequences, are involved in the regulation of transcriptional activity of the gamma-GCSh gene.

Two distinct species of amyloid beta protein (A beta) with different C-termini, A beta 42(43) and A beta 40, are deposited in senile plaques (SP) of Alzheimer's disease (AD), with the former being far predominant. To investigate whether A beta 42(43) also predominates over A beta 40 in normal aging, we examined by immunocytochemistry the C-termini of A beta in SP in the brains of non-demented aged individuals and compared the results with those in AD. Virtually all SP were A beta 42(43)-positive; of these 12% in non-demented aged individuals and 25% in AD patients (mean of three areas examined) were also A beta 40-positive. In both the AD and non-demented groups, 2/3 of the A beta 40-positive SP were typical cored SP. These results indicate that A beta 42(43) is the predominant species deposited in SP in normal aging, and there is no qualitative difference in terms of the C-terminus of A beta in the parenchymal amyloid deposition between normal aging and AD.

The ATP-dependent glutathione S-conjugate export pump (GS-X pump) has been suggested to play a role in the mechanism of cisplatin resistance. The purpose of this study was to determine the relationship between intracellular glutathione (GSH) levels and GS-X pump activity and whether GS-X pump overexpression results in cisplatin resistance. We transfected the human gamma-glutamylcysteine synthetase (gamma-GCS) gene into a human small-cell lung cancer cell line, SBC-3, producing SBC-3/GCS. The intracellular GSH content of SBC-3/GCS was twice that of the parental line, its GS-X pump activity was significantly enhanced and cellular cisplatin accumulation decreased. SBC-3/GCS showed higher resistance (relative resistance value of 7.4) to cisplatin than the parental line SBC-3. These data indicate that gamma-GCS gene overexpression induces cellular cisplatin resistance associated with increases in both the GSH content and GS-X pump activity, resulting in reduced cisplatin accumulation. In conclusion, GS-X pump expression is related to cellular GSH metabolism and involved in cisplatin resistance.

In order to investigate the regulation of glucose transporter gene expression in the altered metabolic conditions of obesity and diabetes, we have measured mRNA levels encoding GLUT2 in the liver and GLUT4 in the gastrocnemius muscle from various insulin resistant animal models, including Zucker fatty, Wistar fatty, and streptozocin(STZ)-treated diabetic rats. Northern blot analysis revealed that GLUT2 mRNA levels were significantly (P less than 0.001) elevated in 14 wk Zucker fatty and Wistar fatty rats relative to lean littermates but were similar in these two groups at 5 wk of age. Furthermore, there was significant increase (P less than 0.01) in GLUT2 mRNA levels in STZ diabetic rats at 3 wk after treatment. GLUT4 mRNA levels were not significantly different between control and insulin resistant rats in all animal models. These results indicate that neither hyperinsulinemia nor hyperglycemia affects GLUT4 mRNA levels in the muscle. However, GLUT2 mRNA levels in the liver were elevated in obesity and diabetes, although this regulatory event occurred independently from circulating insulin or glucose concentrations.

The expression of five facilitative glucose transporter genes, GLUT1 (erythrocyte type), GLUT2 (liver type), GLUT3 (brain type), GLUT4 (muscle/fat type), and GLUT5 (small intestine type), was examined in human cancer tissues of the digestive system by RNA blotting analysis. The amounts of the GLUT1, GLUT2, and GLUT3 transcripts were elevated in most cancer tissues studied, although the expression of the GLUT2 gene is primarily restricted to the liver. On the other hand, mRNA levels of GLUT4 and GLUT5 were below sensitivity in all cancer tissues examined. These results suggest that over-expression of GLUT1 and GLUT3 might be closely related with tissue development and that the acceleration of glucose uptake by transformed cells may result, at least in part, from the increase in the expression of these two glucose transporters.

Gene expression of liver facilitated glucose transporter was rapidly induced during the liver regenerating process in rats. It reached maximum of 2.7 times at 8 hr of the regenerating course and returned to normal by 48 hr. The protein synthesis inhibitor, cycloheximide, did not interfere with the increased gene expression of liver facilitated glucose transporter. By contrast, erythrocyte/brain-type glucose transporter mRNA could not be detected in the livers of partially hepatectomized rats and sham-operated rats. The plasma glucose levels were transiently increased within 2 hr of the regenerative course and then decreased to a nadir at 4 hr. These results suggest that the increased gene expression of liver facilitated glucose transporter contributes to the decrease in plasma glucose levels.

We have studied the role of vitamin D in the regulation of gastrin and gastric somatostatin secretion from the isolated perfused rat stomach. In Ca-deficient vitamin D-deficient rats (Ca(-)D(-) group), the basal and bombesin-stimulated gastrin and gastric somatostatin release (basal IRGa, basal IRS, sigma delta IRGa, and sigma delta IRS) all were significantly lower than in Ca-replete vitamin D-replete rats (Ca(+)D(+) group), and also lower than in Ca-replete vitamin D-deficient rats (Ca(+)D(-) group) except for the basal IRGa. In the Ca(+)D(-) group, the basal IRGa and IRS, and sigma delta IRS were not significantly lower than in the Ca(+)D(+) group. Although there was no significant impairment in basal IRGa, sigma delta IRGa in the Ca(+)D(-) group was significantly lower than in the Ca(+)D(+) control group. Thus, the gastrin and gastric somatostatin secretion from the Ca-deficient vitamin D-deficient rats were impaired. In addition, the impaired gastrin and gastric somatostatin secretions seem to be caused not only by a decrease in serum Ca but also by the reduced effect of the vitamin D on the G and gastric D cells.

The right gastroepiploic artery (GEA) was studied angiographically and histologically to determine its suitability for coronary artery bypass grafting. One hundred celiac angiograms demonstrated that the right GEA has the appropriate size (diameter less than 1.5 mm, 4%; 1.5 to 2 mm, 29%; more than 2 mm, 67%) and length (less than half of the greater curvature, 5%; more than half of the greater curvature, 95%; more than two-thirds of the greater curvature, 34%) for use as an in situ graft. A stenotic lesion of a GEA was observed in only 1 angiogram. Histological examination of a right GEA from 5 patients who had undergone gastrectomy demonstrated no evidence of arteriosclerosis. Encouraged by these results, we performed a coronary artery bypass reoperation utilizing an in situ right GEA graft in 2 women. Postoperative angiograms showed good patency of those grafts. The patients recovered well and were free from angina.

An experiment was performed to examine whether the acute increase in insulin release induced by oral glucose ingestion is associated with alterations in pancreatic preproinsulin mRNA (PImRNA) levels. Rats either fed ad libitum or after overnight fast were used. Fasted rats were administered glucose orally in a conscious, unrestrained state. Pancreatic RNA was extracted and the relative level of PImRNA was determined by dot blot analysis with a cloned rat preproinsulin I cDNA probe. In fasted animals PImRNA levels decreased compared with those of fed animals and showed no significant changes after acute glucose administration, while blood glucose and plasma insulin increased rapidly to maximum values at 15 min after glucose administration. Although the transcription rate was not directly measured in this experiment, it is possible that the rapid increase in insulin release from the beta cell under physiological conditions is controlled by post-transcriptional regulations.

2[2-(4.5-Dihydro-1H-imidazol-2-yl)-1-phenylethyl] pyridine dihydrochloride sesquihydrate (DG-5128) is an alpha 2-specific-adrenergic antagonist. We have studied the effect of DG-5128 on insulin and somatostatin release from the isolated perfused rat pancrease. DG-5128 stimulated somatostatin and insulin release not only at a low glucose concentration but also at a high glucose concentration. These findings suggest that an alpha 2-adrenergic receptor plays an important role in the regulation of insulin and somatostatin secretion.

ATP and AMP were immediately converted into ADP by intact cells of Escherichia coli in the presence of Mg2+, while ADP was also rapidly converted into ATP and AMP under the same conditions. Adenylate kinase was released when E. coli cells were converted to spheroplasts by treatment with lysozyme-EDTA or osmotic shock. Adenylate kinase activities detected in the cytoplasm, periplasm and membrane fractions were approximately 58%, 36% and 6% of the total cellular activity, respectively. These results indicate that adenylate kinase in E. coli occurs in the periplasm as well as the cytoplasm.

Two patients with both coronary artery disease and leg ischemia were successfully treated with a combined revascularization procedure. Coronary arteries were bypassed with in situ internal mammary artery grafts, and bilateral femoral arteries were bypassed with expanded polytetrafluoroethylene grafts descended from the ascending aorta through the preperitoneal abdominal wall tunnel. Both patients recovered well and experienced no angina or claudication.

The low-power ultrasonic aspirator was used for the dissection of the internal mammary artery (IMA) in 20 patients undergoing coronary artery bypass grafting. Harvesting time was shorter and the amount of bleeding was less than with the ordinary method. The short-term patency rate (1 to 6 months) for those IMA grafts was 95% (19 of 20 remained patent). These results have encouraged us to use the ultrasonic aspirator routinely for IMA dissection.