Assessment of antioxidative activity of lipid- and water-soluble vitamins in human whole blood. Comparative analysis between a biological test and chemical methods

Assessment of the antioxidant activity of vitamins and other compounds is of interest in the understanding of their in vivo effects. In this study, we have investigated the activity of several lipid and water-soluble vitamins in human whole blood. Measurements were carried out using a biological test that enables the evaluation of both red blood cells and plasma resistance against free radical activity induced by 2,2'-azobis (2-amidinopropane)hydrochloride (AAPH). Antioxidant activity of vitamins has been determined by using the biological test versus chemical methods (chemiluminescence, DMPD radical). We have observed strong anti-oxidant potentials for vitamins B6 and B9 with biological tests, but not with chemical methods. At 10 microM, the vitamin B9 efficiency in inhibiting radical-induced red blood cell hemolysis was almost three times higher than vitamin C efficiency and two times higher than alpha-tocopherol efficiency. Antioxidant activity was not observed for vitamins B1 or B2, nor for retinol. The weak activity of beta-carotene still remains to be investigated particularly in relation to oxygen pressure. Our study demonstrated that the biological test is more useful than the chemical methods employed in this instance, for the evaluation of antioxidant capacity of lipophilic and putatively biologically active compounds.     

Beneficial effects of the bioflavonoids curcumin and quercetin on early function in cadaveric renal transplantation: a randomized placebo controlled trial

BACKGROUND: The bioflavonoids quercetin and curcumin are renoprotective natural antioxidants. We wished to examine their effects on early graft function (EF). METHODS: Between September 2002 and August 2004, 43 dialysis dependent cadaveric kidney recipients were enrolled into a study using Oxy-Q which contains 480 mg of curcumin and 20 mg of quercetin, started after surgery and taken for 1 month. They were randomized into three groups: control (placebo), low dose (one capsule, one placebo) and high dose (two capsules). Delayed graft function (DGF) was defined as first week dialysis need and slow function (SGF) as Cr >2.5 mg/dl by day 10. Category variables were compared by chi squared and continuous variables by Kruskal-Wallis. RESULTS: There were four withdrawals: one by patient choice and three for urine leak. The control group had 2/14 patients with DGF vs. none in either treatment group. Incidence of EF was control 43%, low dose 71% and high dose 93% (P=0.013). Serum creatinine was significantly lower at 2 days (control 7.6+/-2.1, low 5.4+/-0.6, high 3.96+/-.35 P=0.0001) and 30 days (control 1.82+/-.16, low 1.65+/-.09, high 1.33 +/-.1, P=0.03). Acute rejection incidence within 6 months was control 14.3%, low dose 14.3% and high dose 0%. Tremor was detected in 13% of high dose patients vs. 46% of others. Urinary HO-1 was higher in bioflavonoid groups. CONCLUSION: Bioflavonoid therapy improved early graft function. Acute rejection and neurotoxicity were lowest in the high dose group. These bioflavonoids improve early outcomes in cadaveric renal transplantation, possibly through HO-1 induction.     

Genitourinary malignancies in solid organ transplant recipients

Malignancy is a recognized complication of transplantation. Genitourinary cancers are the second most common tumors in transplant recipients with prostate cancer and renal cell carcinoma the most common. Unlike the more common skin malignancies, genitourinary tumors have a significant impact on both graft and patient survival. Surgical and radiation treatments need to consider the location of heterotopic transplants and administration of chemotherapy may need alteration in light of immunosuppression being used. The major genitourinary malignancies and their management will be reviewed in this article with emphasis on the concerns that arise in a transplant recipient.     

Effects of head extension on undisturbed upright stance control in humans

The purpose of the present experiment was to investigate whether and how the head extended posture, commonly encountered in many routine activities, affects undisturbed upright stance control mechanisms in humans. Sixteen young healthy adults stood feet together, with their eyes closed and were asked to sway as little as possible in two Neutral and Extended head conditions. Centre of pressure (CP) displacements, recorded using a force platform, were used to compute the motions of the vertical projection of the centre of gravity (CG(v)) and those of the difference CP - CG(v). A time-domain analysis shows increased mean velocity and surface covered by the trajectory of both elementary motions in the Extended head condition. A frequency analysis also reveals increased root mean squares on the CP - CG(v) motions, suggesting increased muscular activity in the Extended head condition. Furthermore, similar changes occur on CG(v) motions. Finally, modelling these trajectories as a fractional Brownian motion process demonstrates increased spatial transition point co-ordinates at which the corrective process is initiated and a more deterministic control mechanism in this corrective process involving CG(v) motions in the Extended head position. Together, the present findings suggest that head extension position yields a reorganisation of the control mechanisms for maintaining undisturbed upright stance.     

Repeated injections of 131I-rituximab show patient-specific stable biodistribution and tissue kinetics

Purpose It is generally assumed that the biodistribution and pharmacokinetics of radiolabelled antibodies remain similar between dosimetric and therapeutic injections in radioimmunotherapy. However, circulation half-lives of unlabelled rituximab have been reported to increase progressively after the weekly injections of standard therapy doses. The aim of this study was to evaluate the evolution of the pharmacokinetics of repeated ¹³¹I-rituximab injections during treatment with unlabelled rituximab in patients with non-Hodgkins lymphoma (NHL).Methods Patients received standard weekly therapy with rituximab (375 mg/m²) for 4 weeks and a fifth injection at 7 or 8 weeks. Each patient had three additional injections of 185 MBq ¹³¹I-rituximab in either treatment weeks 1, 3 and 7 (two patients) or weeks 2, 4 and 8 (two patients). The 12 radiolabelled antibody injections were followed by three whole-body (WB) scintigraphic studies during 1 week and blood sampling on the same occasions. Additional WB scans were performed after 2 and 4 weeks post ¹³¹I-rituximab injection prior to the second and third injections, respectively.Results A single exponential radioactivity decrease for WB, liver, spleen, kidneys and heart was observed. Biodistribution and half-lives were patient specific, and without significant change after the second or third injection compared with the first one. Blood T_1/2, calculated from the sequential blood samples and fitted to a bi-exponential curve, was similar to the T_1/2 of heart and liver but shorter than that of WB and kidneys. Effective radiation dose calculated from attenuation-corrected WB scans and blood using Mirdose3.1 was 0.53+0.05 mSv/MBq (range 0.48–0.59 mSv/MBq). Radiation dose was highest for spleen and kidneys, followed by heart and liver.Conclusion These results show that the biodistribution and tissue kinetics of ¹³¹I-rituximab, while specific to each patient, remained constant during unlabelled antibody therapy. RIT radiation doses can therefore be reliably extrapolated from a preceding dosimetry study.     

Transfusion free surgery: single institution experience of 27 consecutive liver transplants in Jehovah's Witnesses

BACKGROUND: Despite the risks associated with transfusion, the medical community continues to view blood as a safe and abundant product. In this article, we provide an effective strategy to accomplish orthotopic liver transplantation without transfusion. STUDY DESIGN: From June 1999 through July 2004, 27 liver transplantations were performed in Jehovah's Witness patients at the USC-University Hospital (24 adults, 3 children). Nineteen of these were living donor (LD) and eight were deceased donor (DD) liver transplants. Preoperative blood augmentation with erythropoietin and iron was achieved. At induction, all LD and six of eight DD recipients underwent acute normovolemic hemodilution (ANH), and the operation was conducted under conditions of moderate anemia. Cell scavenging techniques were used. Acute normovolemic hemodilution and salvaged blood were returned as needed during bleeding or on completion of transplantation. RESULTS: The preoperative liver disease severity score was higher in the deceased donor group. We had 100% graft and patient survivals in the LD group, and 75% in the DD recipients. Two DD recipients died. The remaining are all alive and well, with a mean followup of 965 days (range 266 to 1,979 days) in the LD group and 624 days (range 119 to 1,132 days) in the DD group. CONCLUSIONS: Preoperative blood augmentation and acute normovolemic hemodilution provide a safe cushion against operative blood loss. Elective living donor liver transplantation allows full implementation of a transfusion-free strategy in the setting of early hepatic failure, portal hypertension, and anemia. This feat is an important step toward global standardization of transfusion-free surgical practice and an important response to widespread blood shortages and transfusion risks.     

How to deal with difficult microsurgical end-to-side anastomoses

Although unexplained thrombotic failures still exist, the majority of free-flap failures are due to identifiable technical failures, indicating that an excellent operative technique remains the key point. However, some clinical circumstances, such as damaged or deeply located vessels, are related to a higher thrombotic risks, demanding refinements of the microsurgical procedure to avoid higher failure rates. We reviewed 195 free flaps in the lower leg in order to quantify these situations and how we dealt with them. In total, six flaps were performed with a T-interposition to cope with difficult end-to-side anastomoses on damaged vessels. In two cases, the use of a funnel-shaped vein graft facilitated difficult end-to-side anastomoses in the popliteal area. The authors believe that these refinements of microsurgery should not be first-choice procedures, but they have proven to be a useful tool for certain microsurgical reconstructions.     

Early left ventricular function recovery after trap-door coronary transfer repair of ALCAPA in an adult patient

Anomalous origin of the left coronary from the pulmonary artery (ALCAPA) is a rare congenital malformation, which may result in myocardial infarction, congestive heart failure, and sudden death if left untreated. Despite frequently advanced pathologic changes, there seems to be significant potential for the recovery of myocardial function in individuals with left ventricular dysfunction after the establishment of physiologic coronary circulation, particularly in the pediatric population. Reports of ALCAPA repair in adulthood are scarce and little information exists regarding the response of the left ventricle to revascularization in this age group. In this report, repair of ALCAPA in a significantly symptomatic adult patient with ventricular dysfunction is described, leading to an early recovery of left ventricular function.