In vitro evaluation of ablation parameters of normal and fibrous aorta using smooth excimer laser coronary angioplasty

A modified exeimer laser energy delivery system was used to irradiate 100 segments of normal and fibrous aorta in vitro. The laser beam was scanned into 8 fiber bundles consisting of 50 fibers each resulting in a reduction of the applied pulse energy. The total repetition rate was increased to 150 Hz in order to keep the repetition rate per fiber bundle close to 20 Hz and to minimize thermal injury. The results demonstrate that effective ablation (etch rate per 8 pulses > 2.0 μm) occurred at an energy fluency of 50 mJ/mm² in both normal and fibrous aorta. Tissue damage (carbonization, tissue separation, fissures, cracks, and vacuolization) was in a range of 100 ± 28 to 152 ± 30 μm for normal aorta and in a range of 57 ± 35 to 110 ± 39 μm for fibrous aorta. We conclude that effective ablation of normal and fibrous human aorta can be achieved by the application of smooth excimer laser coronary angioplasty. This improvement of excimer laser technology may result in a reduction of shock wave- and cavitation-induced damage leading to a reduction of tissue injury. However, this awaits further in vitro and in vivo confirmation. © 1993 Wiley-Liss, Inc.     

Self-inflicted orbital and intracranial injury with a retained foreign body, associated with psychotic depression: Case report and review

Reports of intracranial self-multilation by psychotic individuals are associated with severe mental disorders, criminality, or both. We describe a psychotically depressed male who drove a ballpoint pen through his right medial canthus and into his intracranial compartment. The patient developed a cavernous sinus syndrome and a traumatic dissection of the cavernous portion of the carotid artery. The pen was removed intraoperatively. Postoperatively, the patient was placed on a course of broad-spectrum antibiotics, antidepressants, and antipsychotic medications, and he has received long-term psychiatric follow-up. The literature related to these unusual cases is reviewed, and relevant surgical, medical, and psychiatric aspects of treatment are discussed.     

Myoblast fusion in Drosophila melanogaster is mediated through a fusion-restricted myogenic-adhesive structure (FuRMAS).

During myogenesis in Drosophila embryos, a prominent adhesive structure is formed between precursor cells and fusion-competent myoblasts (fcms). Here, we show that Duf/Kirre and its interaction partners Rols7 (found in founder myoblasts and growing myotubes) and Sns (found in fcms) are organized in a ring-structure at the contact points of fcms with precursor cells, while cytoskeletal components like F-actin and Titin are centered in this ring in both cell types. The cytoplasmic protein Blow colocalizes with the actin plugs in fcms after cell adhesion. Furthermore, the requirement of additional as yet unidentified components was demonstrated by using mammalian C2C12 myoblasts. In this study, we propose that the fusion-restricted myogenic-adhesive structure (FuRMAS) is pivotal in linking cell adhesion as well as local F-actin assembly and dynamics to downstream events that ultimately lead to plasma membrane fusion. Moreover, we suggest that the FuRMAS may restrict the area of membrane breakdown.     

Deltoid flap combined with fascia lata autograft for rotator cuff defects: a histologic study

The purpose of this study was to compare the histological characteristics of an autogenous fascia lata graft alone and a fascia lata graft combined with a deltoid flap in the reconstruction of rotator cuff tears. Ten New Zealand white rabbits were divided into two groups. Infraspinatus tendon defects (1 × 1 cm) were created in each animal. Reconstruction consisted of either a fascia lata graft alone or a fascia lata graft combined with a distally based deltoid flap. At 3 months, tissue harvest and histological analysis was performed. Compared to the fascia lata graft alone, there was significantly increased remodeling activity and neovascularization in the group that included a deltoid flap. Also, there was pronounced interdigitation at the graft/flap interface in the latter group. A mutually beneficial relationship may exist when an autogenous fascial graft is combined with a functional deltoid flap for reconstructing large rotator cuff defects.     

Biphasic Shocks Compared with Monophasic Damped Sine Wave Shocks for Direct Ventricular Defibrillation during Open Heart Surgery

Background: Biphasic waveform shocks are more effective than monophasic shocks for transchest ventricular defibrillation, atrial cardioversion, and defibrillation with implantable defibrillators but have not been studied for open chest, intraoperative defibrillation. This prospective, blinded, randomized clinical study compares biphasic and monophasic shock effectiveness and establishes intraoperative energy dose-response curves.

Methods: Patients undergoing cardiothoracic surgery with bypass cardioplegia were randomly assigned to the monophasic or biphasic shock group. Ventricular fibrillation occurring after aortic clamp removal was treated with escalating energies of 2, 5, 7, 10, and 20 J until defibrillation occurred. If ventricular fibrillation persisted, a 20-J crossover shock of the other waveform was used.

Results: Cumulative defibrillation success at 5 J, the primary end point of the study, was higher in the biphasic group than in the monophasic group (25 of 50 vs. 9 of 41 defibrillated;P = 0.011). In addition, the biphasic group required lower threshold energy (6.8 vs. 11.0 J;P = 0.003), less cumulative energy (12.6 vs. 23.4 J;P = 0.002), and fewer shocks (2.5 vs. 3.5;P = 0.002). Crossover-shock effectiveness did not differ between groups. Dose-response curves show biphasic shocks to have higher cumulative success rates at all energies tested.     

Long-term neuroretinal full-thickness transplants in a large animal model of severe retinitis pigmentosa

Background The purpose of this study was to explore neuroretinal transplantation in a large animal model of severe retinitis pigmentosa and to establish graft development, long-term survival, graft-host integration, and effects on the host retina. Methods Rhodopsin transgenic pigs, aged 6 months, received in one eye a fetal full-thickness neuroretinal sheet in the subretinal space by means of vitrectomy and retinotomy. Six months postoperatively, eyes were studied in the light microscope and with immunohistochemical markers. Full-field electroretinography (ERG) was performed at 4 and 6 months. Results Laminated grafts with well-organized photoreceptors, rod bipolar cells, and Müller cells were found in five of six eyes. Neuronal connections between graft and host retina were not seen. In the five eyes containing a graft, the number of surviving rods in the host retina was significantly higher compared with unoperated eyes. The ERG did not reveal any significant difference in b-wave amplitude between operated and control eyes, but the cone-derived response in operated eyes increased significantly from 4 to 6 months while the rod response in control eyes decreased significantly. Conclusions Fetal full-thickness neuroretina can be transplanted safely to an eye with severe retinal degeneration. In their major part, the transplants develop a normal laminated morphology and survive for at least 6 months. Graft and host retinal neurons do not form connections. Retinal function in the host is reduced initially by the surgical trauma, but the presence of a well-laminated graft counteracts this effect and rescues rods from degeneration. Supported by The Foundation Fighting Blindness (grant# C-NC02-798-0078), The Faculty of Medicine, University of Lund, The Swedish Research Council, The Princess Margaretas Foundation for Blind Children, The 2nd ONCE International Award for New Technologies for the Blind.     

Impairment of bone turnover in elderly women with hip fracture

Summary Hip fracture is one of the most severe consequences of osteoporosis affecting aged women. However, abnormalities of bone turnover responsible for bone loss in this condition have not been clearly defined. To further evaluate the bone metabolic status of women sustaining hip fracture, we have prospectively measured serum osteocalcin as a marker of bone formation and urinary excretion of pyridinoline (Pyr) and deoxypyridinoline (D-pyr) cross-links as markers of bone collagen degradation in 174 independently living women (80 ± 8 years) within a few hours after a hip fracture. Comparison was made with 77 age-matched controls (80 ± 5 years) and 17 premenopausal women (39 ± 3 years). In addition 15 of the patients were followed with daily measurements during the first postoperative week. At the time of admission osteocalcin was 20% lower in the fractured women compared to the elderly controls (7.6 ± 3.8 vs. 9.5 ± 4.5 nglml,P = 0.001). Pyr and D-pyr were 36% and 40% higher, respectively (P = 0.0001), than in elderly controls and 85% and 76% higher than in premenopausal controls (P = 0.0001). Serum osteocalcin did not correlate with the cortisol level measured at the same time (r = 0.03, ns), nor with serum albumin and creatinine. Serum osteocalcin remained unchanged within 18 hours after fracture, whereafter it progressively decreased until the third postoperative day. No correlation was noted between the excretion of pyridinoline cross-links and the time elapsed from fracture.These data suggest that the abnormal levels of osteocalcin and pyridinolines are unrelated to traumatically induced acute changes, but reflect abnormalities of bone turnover existing prior to the fracture. Thus, hip-fracture patients have biochemical evidence of decreased bone formation and increased bone resorption when compared to age-matched controls. We suggest that these abnormalities may play a role in the decrease of the bone mass and the consequently increased bone fragility that characterize the osteoporotic hip fracture in the elderly.     

Education of the aged in a residential setting--motivation for participation of "educational novices" within the scope of a "bring" structure

Every inhabitant aged 60 years and over in a working class district in Kassel (N = 568) was visited and invited to discussion groups (topics were "growing old", "health", "care" and others) and to excursion activities. 10% of the people were interested; 7% actually took part. In comparison with a control group of participants from other districts, it was shown that it is possible to mobilize some of those people who have had low-level schooling and only a little experience of further education.     

CGP 6809 — A new nitrosoureido-sugar derivative with activity in human tumor xenografts

Summary CGP 6809 [ethyl-6-deoxy-3,5-di-O-methyl-6-(3-methyl-3-nitrosoureido)--d-glucofuranoside] is a new methylnitrosoureido-sugar derivative that has been shown to be active against a broad spectrum of transplantable tumours in mice and rats [14]. We investigated the anti-tumour effect of CGP 6809 in ten selected, human tumour xenograft lines growing s. c. in nude mice. The p. o. administration of 125 mg/kg per day for 10–15 days was less toxic (lethality 12% in tumour-bearing nude mice) than the i. p. injection of 62.5 mg/kg per day (lethality 22%). The anti-tumour effect was similar for both application routes; two large bowel cancers responded to treatment with CGP 6809, rectal cancer CXF 158 showed a remission, and the rapidly growing, undifferentiated colonic cancer CXF 280 exhibited a transient no-change. Furthermore, remissions were observed in the epidermoid lung cancer LXF 322 and in thyroid cancer 117. Tumour progression was found in another epidermoid lung cancer and in three stomach cancers, one melanoma, and one soft tissure sarcoma. CGP 6809 is a promising new agent for clinical trials, especially for large bowel and epidermoid lung cancer.Supported in part by grant PTB 8467 from the Bundesminister für Forschung und Technologie, Bonn, FRG