Smooth muscle cells (SMCs) from prosthetic vascular grafts constitutively secrete higher levels of collagen than aortic SMCs. Lipid oxidation products accumulate in grafts, and we postulated that they stimulate SMC production of collagen. The effect of oxidized low-density lipoprotein (oxLDL) on type I collagen secretion by aortic and graft SMCs was compared. SMCs isolated from the canine thoracic aorta or Dacron thoracoabdominal grafts (n = 10) were incubated with native LDL or oxLDL (0-400 microg cholesterol/ml) for 72 h. Type I collagen in the conditioned medium was measured by ELISA. OxLDL increased collagen production by graft SMCs from 4.1 +/- 0.3 to 11.0 +/- 0.4 ng/microg DNA and by aortic SMCs from 2.3 +/- 0.1 to 3.5 +/- 0.2 ng/microg DNA. Native LDL had little effect. LY-83583, a superoxide generator, stimulated a dramatic increase in collagen secretion by graft SMCs and a smaller but significant elevation by aortic SMCs. OxLDL has been shown to increase PDGF production by graft SMCs, and PDGF can stimulate collagen production. Anti-PDGF antibody inhibited the increase in collagen production by graft SMCs that was stimulated by oxLDL, implicating PDGF as one mechanism of oxLDL-induced collagen production. Lipid oxidation products that accumulate in prosthetic vascular grafts can cause an oxidative stress that stimulates PDGF production by graft SMCs that in turn stimulates collagen production, contributing to the progression of intimal hyperplasia.

Absood, Afaf, Akira Furutani, Tsutomu Kawamura, and Linda M. Graham. Differential PDGF secretion by graft and aortic SMC in response to oxidized LDL.

The present study was conducted to evaluate the degree of stress in patients induced by minimally invasive cardiac surgery (MICS) in comparison with that caused by conventional cardiac surgery. We did this by assessing the incidence of systemic inflammatory response syndrome (SIRS). A total of 48 adult patients who underwent surgery for single valve disease were included in this study, 27 of whom underwent conventional surgery and 21 MICS. We evaluated the stress inflicted on the patients in these two groups by analyzing the duration and degree of SIRS and the level of C-reactive protein (CRP). SIRS was assessed by measuring body temperature, heart rate, respiratory rate, and white blood cell counts. There were no significant differences in the operating times, perfusion times, or aorta clamp times between the two groups; and the mean volume of blood transfusion did not differ significantly either. There was no significant difference in the incidence of SIRS or the mean duration of SIRS between the two groups. The CRP levels did not differ significantly between the two groups. Thus although MICS is superior to conventional cardiac surgery in that only a small skin incision is required, the stress experienced by the patient may be the same as that experienced by the patient undergoing conventional cardiac surgery.

No abstract

A multicentre study of ABO incompatible kidney transplantation using Biosynsorb was started in Japan in November 1989. A total of 51 cases were registered comprising 23 cases of A incompatibility, 26 cases of B incompatibility and two cases of AB incompatibility. The .removal of antibodies (IgG and lgM) was carried out using Biosynsorb in 16 cases, plasmapheresis in four cases and use of both combined in 31 cases. The treatment using Biosynsorb was repeated 3.4 times on average. Serum titres of anti-A (IgG and lgM) antibodies decreased to 4.9 ± 5.0 and 2.7 ± 1.7 and for anti-B titres decreased to 2.8 ± 3.5 and 2.4 ± 3.2. Rejection was found in 33 cases: hyperacute one, accelerated acute five, and acute 27. In two cases rejection was developed concomitantly with a steep elevation in antibody titres. Three patients died, two with functioning grafts. Eight grafts were lost. Patient and graft survivals at 2 years were 94.1% and 84.3%, respectively. From these results it is concluded that: 1. Biosynsorb and plasmapheresis are effective in removing anti-A and anti-B antibodies; 2. graft and patient survivals are similar to those in ABO compatible cases; 3. anti-A and anti-B titres less than 16 are recommended at the time of transplantation; 4. anti-A and anti-B titres higher than 128 may be considered as a risk factor for rejection in the early stages after transplantation.