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Preservation of intercostal arteries during thoracic aortic procedures reduces the risk of post-operative paraparesis. The origins of the intercostal arteries are visible on pre-operative computed tomography angiography (CTA), but rarely on intra-operative angiography. The purpose of this report is to suggest an image fusion technique for intra-operative localisation of the intercostal arteries during thoracic endovascular repair (TEVAR).

Background and Aims: This retrospective study was undertaken to examine the risks associated with obstruction of the coeliac trunk in the process of treating aneurysms with endografting.Material and Methods: 120 patients were treated by endografting for aneurysmal disease. Of these, a subgroup of 9 patients had their celiac trunk covered. If possible, a preoperative angiography was performed to evaluate collateral flow from the superior mesenteric artery. This was considered to predict the risk for ischemia.Results: None of the patients had any severe clinical event of the celiac trunk occlusion or clinical signs of intestinal ischemia. Three patients had transient increase of liver enzymes.Conclusions: In cases where the distal landing zone of the descending thoracic aorta is to short for endografting, covering of the celiac trunk may be an option if no other surgical alternative is apparent. Preoperative angiography to visualise the presence of collateral vessels from the superior mesenteric artery is recommended.

Brazilian plants are potential sources of useful edible and medicinal plants. Hydromethanolic extracts prepared from 54 medicinal plants used in folk medicine to treat infections were screened for antiviral properties against five different viruses (HSV-1, HSV-2, poliovirus type 2, adenovirus type 2 and VSV). Fifty-two percent of the plant extracts exhibited antiviral activity against one or more tested viruses. More specifically, 42.6 % showed activity against HSV-1 (herpes simplex virus type 1), 42.6 % against HSV-2 (herpes simplex virus type 2), 26 % against poliovirus and 24 % against VSV (vesicular stomatitis virus). None of the extracts was active against adenovirus. Trixis praestans(Vell.) Cabr. and Cunila spicataBenth. extracts were further characterized for antiviral activity.

Objective:: to assess the representativity of small vascular samples with regard to the expression of six important factors in atherosclerotic vessels. Materials:: circumferential frozen sections of iliac and femoral arteries (n = 9) from patients undergoing reconstructive bypass surgery. Methods:: immunohistochemistry with antibodies against macrophages (CD68), tumour necrosis factor alpha, tissue factor, tissue plasminogen activator, urokinase plasminogen activator and plasminogen activator inhibitor type 1. The distribution of these antigens was characterised by computer assisted image analysis. Antigen positive area in randomly chosen samples of varying size was compared with antigen positive area in the whole vessel transections. Results:: marked heterogeneity was found with respect to the expression of these factors in atherosclerotic vessels. The representativity of samples was highly dependent on the size of the samples. PAI-1 was more evenly expressed compared to the other antigens Conclusions:: estimates of the expression of these factors based on small samples from atherosclerotic arteries are unreliable.

The Herpes simplex virus type 1 primosome consists of three subunits that are the products of the UL5, UL8, and UL52 genes. The heterotrimeric enzyme has DNA-dependent ATPase, helicase, and primase activities. Earlier studies show that a subassembly consisting of the UL5 and UL52 gene products was indistinguishable from the heterotrimeric enzyme in its helicase and primase activities. We demonstrate here that the UL8 protein is required for the helicase activity of the UL5/52 subassembly on long duplex DNA substrates (>30 nucleotides) with a single-stranded DNA loading site fully coated with the virus-encoded single strand DNA binding protein, ICP8. The Escherichia coli single strand DNA binding protein cannot substitute for ICP8, suggesting a specific physical interaction between ICP8 and the UL8 protein. Surface plasmon resonance measurements demonstrated an interaction between ICP8 and the UL5/52/8 heterotrimer but not with the UL5/52 subassembly or the UL8 protein alone. At a subsaturating level of ICP8, the UL5/52 subassembly does show helicase activity, suggesting that the subassembly can bind to single-stranded DNA but not to ICP8-coated DNA.

Objective: To study the mechanisms by which haemodynamic function improves following long saphenous vein-saving surgery.Design: Cohort study.Patients: Twenty patients, 14 women and six men, with primary varicose veins.Interventions: Varicose vein surgery by the long saphenous vein-saving technique.Main outcome measures: Preoperative investigation by physical examination, strain-gauge plethysmography, phlebography and measurements of the long saphenous vein diameter at four different locations using high-resolution, real-time ultrasound. Three months following vein-saving surgery, the patients were reassessed with physical examination, strain-gauge plethysmography and measurements of the long saphenous vein diameter.Results: All patients but one showed excellent or good results following surgery. The preoperative diameter of the long saphenous vein was reduced by 40% at four different levels in the operated legs (p<0.01). The venous return time of the same legs increased 2.4 times (p<0.001). The decrease of the long saphenous vein diameter correlated positively with the increase in venous return time (t-50), (r=0.50, p=0.04).Conclusion: The results suggest that the development of incompetent perforators is an early major event in the formation of primary varicose veins. The results also suggest that the long saphenous vein valvular incompetence in varicose veins is attributable to venous wall dilatation rather than degeneration of the valves. The results support the hypothesis that the improvement in haemodynamic function following long saphenous vein-saving surgery is due, at least partly, to a reduction of the long saphenous vein diameter, which in turn tends to restore valvular competence.

The herpes simplex virus type 1 (HSV-1) origin binding protein, OBP, is a DNA helicase specifically stimulated by the viral single strand DNA-binding protein, ICP-8. The stimulation is dependent on direct protein-protein interactions between the C-terminal domain of OBP, delta OBP, and ICP 8 (Boehmer, P.E., Craigie, M.C., Stow, N.D., and Lehman, I.R. (1994) J. Biol. Chem. 269, 29329-29334). We have now observed that this interaction is dramatically influenced by the nature of the DNA ligand. Stable complexes between delta OBP, ICP 8, and double-stranded DNA, presented either as a specific duplex oligonucleotide or a restriction fragment containing the HSV-1 origin of replication, oriS, can be detected by gel chromatography and gel electrophoresis. In contrast, a single-stranded oligonucleotide, oligo(dT)65, will completely disrupt the complex between delta OBP and ICP 8. We therefore suggest that the interaction between delta OBP and ICP 8 serves to position the single strand DNA-binding protein with high precision onto single-stranded DNA at a replication fork or at an origin of DNA replication.

The origin-binding protein (OBP) from herpes simplex virus 1 is a member of the SF2 helicase superfamily and is required for the initiation of DNA synthesis from a viral origin of DNA replication (oriS). The high-affinity binding sites for OBP in oriS, boxes I and II, are separated by an A+T-rich spacer. We used the gel retardation technique to examine the influence of this spacer sequence on the formation of a specific complex, referred to as complex II, between OBP and oriS. The formation of this OBP-oriS complex was greatly promoted by adenosine 5'-[gamma-thio]triphosphate and other nucleotide cofactors. Surprisingly, oriS constructs where the spacer sequence had been altered with approximately half of a helical turn (+4 or -6 base pairs) supported the formation of a more stable complex II than the wild-type origin. DNase I footprinting experiments showed that the cooperative binding of OBP to boxes I and II was affected by the length of the spacer sequence in the same way. In contrast, the ability of oriS-containing plasmids to replicate was most efficient with wild-type oriS. This paradox can be resolved if it is assumed that an ATP-dependent cooperative binding of OBP to properly spaced recognition sequences in oriS is required to induce a conformational change of DNA, thereby facilitating initiation of DNA replication.

A retrospective interhospital study of 171 surgically treated patients with atherosclerotic abdominal aortic aneurysm is presented (Örebro and Göteborg). Elective resection of the aneurysm was performed in 94 of the patients and emergency resection because of rupture or suspected rupture of the aneurysm in 77 cases. the mortality within the first postoperative month was 16% in the electively operated patients and 49% in the emergency operated patients. During the last 3 years, the mortality rate among electively operated patients was considerably lower (10%). the five-year survival rate was more than 50% in the electively operated patients. the main difference in long-term survival rate between emergency and electively operated patients was dependent on the primary mortality. the cause of late death was usually not related to the operation of the aneurysm, but to other manifestations of generalized atherosclerotic disease. the results seem to justify the conclusion that atherosclerotic abdominal aortic aneurysm should be resected irrespective of size and symptoms, unless the patient has symptoms of severe arterial hypertension and/or generalized atherosclerosis.

The rate of unwinding of duplex DNA by the herpes simplex virus type 1 (HSV-1)-encoded helicase-primase (primosome) was determined by measuring the rate of appearance of single strands from a circular duplex DNA containing a 40-nucleotide 5' single-stranded tail, i.e. a preformed replication fork, in the presence of the HSV-1 single strand DNA-binding protein, infected cell protein 8 (ICP8). With this substrate, the rate at low ionic strength was highly sensitive to Mg2+ concentration. The Mg2+ dependence was a reflection of both the requirement for ICP8 for helicase activity and the ability of ICP8 to reverse the helicase reaction as a consequence of its capacity to anneal homologous single strands at Mg2+ concentrations in excess of 3 mM. The rate of unwinding of duplex DNA by the HSV-1 primosome was also determined indirectly by measuring the rate of leading strand synthesis with a preformed replication fork as template in the presence of the T7 DNA polymerase. The value of 60-65 base pairs unwound/s by both methods is consistent with the rate of 50 base pairs/s estimated for the rate of fork movement in vivo during replication of pseudorabies virus, another herpesvirus. Interaction with the helicase-primase did not increase its helicase activity.