The contemporary role of antioxidant therapy in attenuating liver ischemia-reperfusion injury: a review.

Oxidative stress is an important factor in many pathological conditions such as inflammation, cancer, ageing and organ response to ischemia-reperfusion. Humans have developed a complex antioxidant system to eliminate or attenuate oxidative stress. Liver ischemia-reperfusion injury occurs in a number of clinical settings, including liver surgery, transplantation, and hemorrhagic shock with subsequent fluid resuscitation, leading to significant morbidity and mortality. It is characterized by significant oxidative stress but accompanied with depletion of endogenous antioxidants. This review has 2 aims: firstly, to highlight the clinical significance of liver ischemia-reperfusion injury, the underlying mechanisms and the main pathways by which the antioxidants function, and secondly, to describe the new developments that are ongoing in antioxidant therapy and to present the experimental and clinical evidence about the role of antioxidants in modulating hepatic ischemia-reperfusion injury.     

In vitro stability of a novel compliant poly(carbonate-urea)urethane to oxidative and hydrolytic stress.

Poly(ester)urethane and poly(ether)urethane vascular grafts fail in vivo because of hydrolytic and oxidative degradative mechanisms. Studies have shown that poly(carbonate)urethanes have enhanced resistance. There is still a need for a viable, nonrigid, small-diameter, synthetic vascular graft. In this study, we sought to confirm this by exposing a novel formulation of compliant poly(carbonate-urea)urethane (CPU) manufactured by an innovative process, resulting in a stress-free. Small-diameter prosthesis, and a conventional poly(ether)urethane Pulse-Tec graft known to readily undergo oxidation in a variety of degradative solutions, and we assessed them for the development of oxidative and hydrolytic degradation, changes in elastic properties, and chemical stability. To simulate the in vivo environment, we used buffered solutions of phospholipase A(2) and cholesterol esterase; solutions of H(2)O(2)/CoCl(2), t-butyl peroxide/CoCl(2) (t-but/CoCl(2)), and glutathione/t-butyl peroxide/CoCl(2) (Glut/t-but/CoCl(2)); and plasma fractions I-IV, which were derived from fresh human plasma centrifuged in poly(ethylene glycol). To act as a negative control, both graft types were incubated in distilled water. Samples of both graft types (100 mm with a 5.0-mm inner diameter) were incubated in these solutions at 37 degrees C for 70 days before environmental scanning electron microscopy, radial tensile strength and quality control, gel permeation chromatography, and in vitro compliance assessments were performed. Oxidative degradation was ascertained from significant changes in molecular weight with respect to a control on all Pulse-Tec grafts treated with t-but/CoCl(2), Glut/t-but/CoCl(2), and plasma fractions I-III. Pulse-Tec grafts exposed to the H(2)O(2)/CoCl(2) mixture had significantly greater compliance than controls incubated in distilled water (p < 0.001 at 50 mmHg). No changes in molecular weight with respect to the control were observed for the CPU samples; only those immersed in t-but/CoCl(2) and Glut/t-but/CoCl(2) showed an 11% increase in molecular weight to 108,000. Only CPU grafts treated with the Glut/t-but/CoCl(2) mixture exhibited significantly greater compliance (p < 0.05 at 50 mmHg). Overall, results from this study indicate that CPU presents a far greater chemical stability than poly(ether)-urethane grafts do.     

Coronary atherosclerosis of the donor heart--impact on early graft failure.

OBJECTIVE: Due to the shortage of donor hearts, the criteria for organ acceptability have been considerably extended and donor grafts with coronary atherosclerosis are among those offered. This study evaluated whether and to what degree pre-existing coronary atherosclerosis may be acceptable. METHODS: A total of 1253 consecutive HTx recipients were investigated retrospectively for donor-transmitted coronary atherosclerosis (DCAS). Donor-transmitted coronary atherosclerosis was defined as focal atherosclerosis with stenosis of at least 50%. Inclusion criteria were absence of pre-HTx angiogram but performance of angiogram or autopsy within 6 months after heart transplantation. Kaplan-Meier analysis and log-rank test were used. RESULTS: Eighty-five out of 1253 (6.8%) cases were excluded, since coronary evaluation was not performed within 6 months (n=45) or hearts had undergone pre-transplant angiography (n=40). In 1086 patients no donor-transmitted coronary atherosclerosis was found (NDCAS group) and in 82 patients (7%) donor-transmitted coronary atherosclerosis was diagnosed by angiography (n=49) or autopsy (n=33). Single-vessel donor-transmitted coronary atherosclerosis was found in 53/82 patients (DCAS1 group) and double- or triple-vessel donor-transmitted coronary atherosclerosis in 26/82 patients (DCAS2/3 group). Three of the 82 patients with donor-transmitted coronary atherosclerosis were excluded since the autopsy report was unclear regarding degree of atherosclerosis. Early after heart transplantation the 30-day mortality in the NDCAS and DCAS1 groups was 12.2% versus 13.2% whereas in the DCAS2/3 group it was 61.5%. Beyond the first year the annual decrease with and without donor-transmitted coronary atherosclerosis (single-vessel disease) is comparable. CONCLUSIONS: Donor screening without coronary angiogram overlooks significant atherosclerotic lesions in a considerable number of cases (7.0%). Therefore, angiographic donor screening should be performed. Donor grafts with single-vessel coronary atherosclerosis may be accepted as marginal hearts; however, in our opinion, revascularisation (CABG, PTCA) should be considered. Grafts with two- or even three-vessel coronary atherosclerosis seem to have a serious risk for early graft failure. Beyond the first year the outcome of healthy grafts and grafts with donor-transmitted coronary atherosclerosis seems to be comparable.     

Near fatal infection of a patient with a left ventricular assist device due to unrecognized fetal death.

We report on an unusual case of a young female patient who received an implantable LVAD after unsuccessful emergency coronary bypass surgery following acute myocardial infarction. After LVAD placement, it became evident that the patient had been pregnant. She had to undergo gynaecological surgery during mechanical support to remove the deceased fetus.     

Linear birefringence measurements of the in vitro human cornea

This paper presents results of an in vitro investigation of the optical anisotropy of the human cornea. Computer controlled imaging polarimetry and the Jones formalism were used to investigate the distribution of the birefringence and the azimuth angle across the surface of 12 corneas taken from the corneal bank. Each map of the birefringence and the azimuth angle has no rotational symmetry and is different for each cornea. The minimal value of the birefringence always appears in the corneal centre and varies from 9 to 43 degrees for different corneas. Birefringence of the cornea increases monotonically more than one order in the direction of the corneal periphery. Close to the centre of the cornea the azimuth angle is almost constant and varies significantly away from the optical part of the cornea.     

Heterotopic cervical salivary gland tissue in a family with probable branchio-otorenal syndrome

Heterotopic cervical salivary gland tissue was found in a 4-yr-old girl with branchial and otologic abnormalities. Her mother and sister also had heterotopic cervical salivary tissue in association with anomalies that suggest the branchio-otorenal (BOR) syndrome. Heterotopic cervical salivary gland tissue may result from abnormal branchial development.     

Effect of tissue fixatives on telomere length determination by quantitative PCR

Telomere length is a well established marker of cellular senescence and thus biological age. Quantitative PCR allows the determination even from very low amounts of tissue by using telomere specific and single copy gene primers. Comparing a directly processed tissue sample to a 4% formaldehyde fixed one showed a significantly reduced efficiency of PCR reactions (mainly in single copy gene experiments) in a storage time-dependent manner resulting in an artificial increase in reported relative telomere length. This effect was not seen when the tissue was stored in RNA later solution. In summary, telomere length determination from formaldehyde fixed material by quantitative PCR is not a reliable method. Unfortunately therefore, many easily accessible tissue samples from pathology laboratories are unsuitable for this technique.     

Elastofibroma dorsi has distinct cytomorphologic features, making diagnostic surgical biopsy unnecessary: cytomorphologic study with clinical, radiologic, and electron microscopic correlations

Elastofibroma dorsi (EFD) is a relatively rare soft tissue mass, probably of reactive nature. The lesion is typically located near the inferior margin of the scapula or between the inferior part of scapula and the chest wall in elderly women. Although location of the tumor together with the age/sex of the patients and radiologic findings is often suggestive of the diagnosis, tissue examination has been considered necessary to confirm the diagnosis. Although the histologic features of EFD are well known, there are only four single case reports of the cytologic findings in the English language literature. We describe the cytologic features of EFD in five patients with correlations to clinical, radiologic, histologic, and electron microscopic findings. The current study suggests that the fine-needle aspiration (FNA) features are highly diagnostic, permitting a firm diagnosis of EFD in a typical clinical setting and eliminating the need for preoperative histologic examination.