Effect of dietary olive oil, corn oil and medium-chain triglycerides on the lipid composition of rat red blood cell membranes

The effects of dietary olive oil, corn oil and medium-chain triglycerides (MCT) on factors that characterized erythrocyte membrane lipid fluidity were studied. Weanling rats were fed for 3 or 5 wk high fat diets (10%) containing olive oil, corn oil or a mixture of MCT with olive oil or corn oil. Total phospholipids and phosphatidylcholine of erythrocyte ghosts obtained from olive oil-fed animals, as compared to those fed corn oil, showed an increase in long-chain polyunsaturated fatty acids (PUFA) of the (n-6) and (n-3) series and a decrease in saturated fatty acids. The addition of MCT to the olive oil diet induced an increase in palmitic, palmitoleic and delta-5,8,11-eicosatrienoic acids and a decrease in long-chain PUFA of the (n-6) series in erythrocyte membrane phospholipids. Conversely, rats fed a mixture of MCT and corn oil, as compared to those fed exclusively corn oil, showed increase in long-chain PUFA of the (n-6) and (n-3) series, with no changes in saturated fatty acid levels. The cholesterol/phosphorus molar ratio showed only a slight increase with MCT supplementation. Olive oil feeding induced important changes in fatty acid composition of erythrocyte membrane phospholipids as compared to corn oil feeding without modifying the cholesterol/phosphorus ratio and MCT feeding slightly affected red blood cell membrane lipid composition.     

Experimental axonopathy induced by immunization with campylobacter jejuni lipopolysaccharide from a patient with guillain‐barré syndrome

Campylobacter jejuni (C. jejunj) infection is the most common antecedent in the axonal variant of Guillain‐Barré syndrome (GBS). Antibodies against nerve gangliosides found in GBS patients recognize cross‐reactive epitopes in the lipopolysaccharide (LPS) of C. jejuni. This led to the molecular mimicry hypothesis of GBS. We immunized eleven rabbits with a LPS extracted from HS:19 C. jejuni strain isolated from a patient with GBS and complete Freund's adjuvant (CFA)(group I). In a second experiment we immunized seven rabbits with LPS, CFA and keyhole limpet hemocyanin (KLH)(group II). All group I rabbits developed high titers of anti‐LPS, anti‐GM1, anti‐GD1b antibodies and lower titers of anti‐GD1a. One rabbit, 50 days after initial inoculation, showed tremor and weakness. All rabbits of group II developed high titres of antiganglioside antibodies and six animals showed weakness 59–113 days after initial inoculation. Two rabbits died. Pathology showed mild to moderate, tendentially grouped, axonal degeneration in sciatic nerves of four out of five animals. Control rabbits of group I (immunized with CFA only) did not develop antibodies, controls of group II (immunized with CFA + KLH) developed low titers of IgG anti‐GM1. None developed neurological signs or showed axonal degeneration. C. jejuni LPS is a potent B‐cell stimulator capable to induce a strong antiganglioside response in rabbits. However, to induce the neuropathy is crucial to employ KLH, a glycoprotein known to stimulate both humoral and cellular responses. This animal model reproduces the pathogenetic process hypothesized in axonal GBS with antiganglioside antibodies post C. jejuni infection.     

Disorders of perfusion of the anterior segment of the eye

Background: We have investigated the vascular perfusion of a wide variety of conditions of the anterior segment using fluorescein angiography.
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process.     

Postoperative radiation therapy in the management of lung cancer

Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate.     

Assessing the validity of an ELISA test for the serological diagnosis of human fascioliasis in different epidemiological situations

Objectives To improve the diagnosis of human fascioliasis caused by Fasciola hepatica and Fasciola gigantica, we evaluated the diagnostic accuracy of an enzyme‐linked immunosorbent assay (ELISA), with Fasciola antigen from the adult liver fluke, for the detection of IgG against fascioliasis in human sera. Methods The sera of 54 fascioliasis cases, originating from three endemic areas, were used in this evaluation: (i) a hyperendemic F. hepatica area where humans usually shed a great number of parasite eggs in faeces (11 sera); (ii) an epidemic F. hepatica area where humans usually shed small amounts of parasite eggs (24 sera) and (iii) an overlap area of both Fasciola species and where human shedding of parasite eggs in faeces is usually scarce or non‐existent (19 sera). One hundred and sixty‐eight patients with other parasitic infections and 89 healthy controls were also analysed. Results The respective sensitivity and specificity of this assay were 95.3% (95% confidence intervals, 82.9–99.2%) and 95.7% (95% confidence intervals, 92.3–97.5%). No correlation between egg output and the OD450 values of the F. hepatica IgG ELISA test was observed. Conclusions This test could be used both as an individual serodiagnostic test for human fascioliasis when backed up by a compatible clinical history together with a second diagnostic technique for other cross‐reactive helminth infections, and in large‐scale epidemiological studies of human fascioliasis worldwide.     

High frequency of Fredrickson's phenotypes IV and IIb in Brazilians infected by human immunodeficiency virus

Background  

Human immunodeficiency virus (HIV) infection is very prevalent in Brazil. HIV therapy has been recently associated with coronary heart disease (CHD). Dyslipidemia is a major risk factor for CHD that is frequently described in HIV positive patients, but very few studies have been conducted in Brazilian patients evaluating their lipid profiles.     

Hematologic and immunomodulatory effects of an interleukin-1 receptor antagonist coinfusion during low-dose endotoxemia in healthy humans

Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra.