Relationship of alternans of monophasic action potential and conduction delay inside the ischemic border zone to serious ventricular arrhythmia during acute myocardial ischemia in dogs

We studied the relationship of conduction delay and monophasic action potential (MAP) at an ischemic border zone to serious ventricular arrhythmia (VA). Measurements were made in 36 adult mongrel dogs 15 minutes after occlusion of the left anterior descending coronary artery. We recorded MAPs and bipolar electrograms simultaneously inside and outside the ischemic border zone in the dog hearts. Of the 36 dogs, 24 that had favorable MAP recordings were chosen and were divided into two groups according to an occurrence of VA. In group A (n = 12), an onset time of VA was 5.1 +/- 0.8 minutes after ischemia, while in group B (n = 12) VA did not occur during ischemia. The conduction delay at the ischemic border zone was significantly greater from 3 minutes after ischemia in group A than in group B. MAP alternans, defined as the difference in duration of two consecutive MAPs inside the ischemic border, was marked in group A but mild in group B. Duration of a small MAP of alternans was markedly shorter than that of a corresponding MAP outside the ischemic border in both groups, but was followed by VA in group A. Duration of a large MAP was markedly prolonged compared with that of a corresponding MAP outside the ischemic border in seven dogs of group A and in only one dog of group B (p less than 0.01), and was followed by VA in seven dogs of group A. Our results suggest that the mechanism of VA is due not only to reentry but also to an injury current flowing from ischemic to nonischemic tissues, because VA was preceded by conduction delay and by a difference in MAP durations when comparing regions inside and outside the ischemic border.     

Inhibition of lens epithelial cell migration at the intraocular lens optic edge: role of capsule bending and contact pressure

PURPOSE: To evaluate the inhibitory effect of a sharp intraocular lens (IOL) optic edge, a sharp capsule bend, and contact pressure between the optic edge and posterior capsule on lens epithelial cell (LEC) migration. SETTING: Department of Ophthalmology, Kyorin University, Tokyo, Japan. METHODS: This in vitro laboratory study evaluated a tumble-polished convex-plano IOL (CP group), an AcrySof IOL (Alcon) with a sharp edge (AS group), a new IOL with a round ridge (RR group), and a new IOL with a sharp ridge (SR group). The 2 new IOLs have high ridges and high angled loops that create firm contact between the ridge and posterior capsule. After sham cataract surgery, an IOL and a capsular tension ring (CTR) were implanted in the capsular bag of rabbit eyes. The extracted capsular bags containing the CTR and IOL were cultured. The inhibitory effect of each IOL on cell migration was analyzed. Furthermore, LEC migration on the posterior capsule was compared in culture between capsules having a sharp right angle and those with gradually curving bends. RESULTS: The inhibitory effect on cell migration was statistically greatest in the SR group followed by the RR, AS, and CP groups. A sharp capsule bend did not inhibit cell migration. CONCLUSIONS: The results suggest that inhibition of cell migration at the optic edge is regulated by the degree of contact pressure between the optic edge and posterior capsule. A sharp capsule bend might indicate strong contact but does not in itself inhibit cell migration.     

Vitrectomy for endophthalmitis after cataract surgery

PURPOSE: To identify risk factors of poor visual outcome with vitrectomy for early-onset endophthalmitis after cataract surgery. PATIENTS AND METHODS: Clinical records of 29 consecutive eyes with endophthalmitis developing within 6 weeks after cataract surgery and that underwent therapeutic vitrectomy between June 1996 and April 2001 were retrospectively reviewed. Twenty-two of the eyes received intravitreal injections of vancomycin and ceftazidime at the time of vitrectomy, and all patients received intravenous antibiotics. Eyes were divided into two groups; group A consisted of 22 eyes with a final visual acuity of 0.2 or greater, and group B consisted of 7 eyes with a final visual acuity of less than 0.2. RESULTS: Fifteen eyes (52%) in group A achieved a visual acuity of 0.5 or better and 8(28%) achieved a visual acuity of 1.0, while 4 eyes in group B developed phthisis bulbi. For eyes with a preoperative visual acuity of hand motions or worse, there was no correlation between final visual acuity and preoperative visual acuity. The overall culture-positive rate was 57%. In group A, methicillin-resistant Staphylococcus epidermidis was identified in 6 eyes, methicillin-resistant Staphylococcus aureus (MRSA) in 3 eyes and enterococcus in 2 eyes. In group B, alpha-hemolytic streptococcus (AHS) was identified in 4 eyes, aspergillus in 1 eye, and MRSA in 1 eye. All isolates were sensitive to vancomycin with the exception of the aspergillus. AHS infection appeared to be associated with wound failure from the initial cataract surgery and a poor visual outcome. Among 3 of the eyes that developed phthisis bulbi, intravitreal injection of antibiotics was not performed. CONCLUSION: Early vitrectomy and intravitreal injection of vancomycin may improve visual outcomes, but infection with AHS may be associated with cataract surgery wound failure and poor visual outcomes.     

A case of advanced gastric cancer successfully treated by neoadjuvant chemotherapy with CPT-11, CDDP and 5-FU

A patient with advanced gastric cancer was treated with combined administration of CPT-11 CDDP and 5-FU before operation. CPT-11 was given intravenously at a dose of 30 mg/m2/day on day 1 and day 8. At the same time, 5 mg/m2/day CDDP and 350 mg/m2/day 5-FU were infused for 2 weeks. The patient experienced no other adverse reaction than a mild degree of nausea. Histological examination of the resected specimen revealed complete disappearance of cancer cells both in the stomach and the regional lymphnodes.     

Are there any differences in acute adverse reactions among five low-osmolar non-ionic iodinated contrast media?

Objectives  

The differences regarding adverse reactions in different low-osmolar non-ionic contrast media had not been investigated previously. Thus, the aims of this study were to identify differences in the incidence of adverse reactions in five different low-osmolar non-ionic contrast media.     

Miyake‐Apple view of inner side of sclerotomy during microincision vitrectomy surgery

Purpose: To examine the inner surface of the sclerotomy during microincision vitrectomy surgery by Miyake‐Apple view. Methods: The anterior half of porcine eyes was attached to a transparent acrylic plate with cyanoacrylate glue. Then, either a 23‐gauge or a 25‐gauge trocar‐cannula was inserted through the sclera obliquely. The inner surface of the entrance site was observed posteriorly by Miyake‐Apple view. These images were compared with the endoscopic view of two patients who underwent vitreous surgery for an epiretinal membrane. Results: When the trocar‐cannula was inserted obliquely, the Miyake‐Apple view showed that the ciliary epithelium at the sclerotomy site was stretched. When the trocar‐cannula was inserted vertically, the ciliary epithelium was folded, and the folds remained even after the trocar was removed. Vitreous strands were seen incarcerated into the sclerotomy site. In human eyes, a folding of the ciliary epithelium was not clearly seen with the endoscopic view but the incarcerated vitreous was seen. Conclusion: The Miyake‐Apple view provided a precise, in vivo, observation of the inner surface of the entry site. It disclosed the morphological stress on the ciliary epithelium by the sclerotomy.     

Evaluation of the acute adverse reaction of contrast medium with high and moderate iodine concentration in patients undergoing computed tomography

Purpose The aim of this prospective study was to evaluate and compare acute adverse reactions between contrast medium containing moderate and high concentrations of iodine in patients undergoing computed tomography (CT). Materials and methods A total of 945 patients undergoing enhanced CT were randomly assigned to receive one of two doses of contrast medium. We then prospectively investigated the incidence of adverse reactions. Iopamidol was used as the contrast medium, with a high concentration of 370 mg I/ml and a moderate concentration of 300 mg I/ml. The frequency of adverse reactions, such as pain at the injection site and heat sensation, were determined. Results Acute adverse reactions were observed in 2.4% (11/458) of the moderate-concentration group compared to 3.11% (15/482) of the high-concentration group; there was no significant difference in incidence between the two groups. Most adverse reactions were mild, and there was no significant difference in severity. One patient in the high-concentration group was seen to have a moderate adverse reaction. No correlation existed between the incidence of adverse reactions and patient characteristics such as sex, age, weight, flow amount, and flow rate. The incidence of pain was not significantly different between the two groups. In contrast, the incidence of heat sensation was significantly higher in the high-concentration group. Conclusions The incidence and severity of acute adverse reactions were not significantly different between the two groups, and there were no severe adverse reactions in either group. Part of this article was presented at the 63rd annual meeting of the Japan Radiological Society     

Reversal of diminished inhibitory sensory gating in cocaine addicts by a nicotinic cholinergic mechanism.

Cocaine addiction, as with other stimulant abuse, produces psychotic symptoms. Although often moderate to mild in severity, these symptoms are, nevertheless, associated with poorer over-all outcome. Recent studies suggest diminished nicotinic cholinergic neurotransmission as a mechanism of a physiological deficit found in schizophrenia, failure of auditory sensory inhibition. Diminished inhibitory sensory gating also occurs in cocaine addicts, probably because of their increased catecholaminergic neurotransmission, which blocks the inhibition. In the present study, 11 cocaine addicts in the first week of detoxification were recorded electrophysiologically, after which the effects of 6 mg of nicotine gum, were assessed in a double-blind placebo-controlled crossover design. The test was repeated 10 days later. Treatment with nicotine, but not placebo, briefly reversed the inhibitory abnormality on both test days. Although nicotine itself may not be a desirable therapeutic agent, because desensitization of nicotinic receptors limits the time course of its effect, the study identifies a previously unexploited therapeutic target for new drug development for the neuropsychiatric sequelae of cocaine addiction.