l-Carnitine and Long-Chain Acylcarnitines are Positively Correlated with Ambulatory Blood Pressure in Humans: The SABPA Study

The prevalence of hypertension in sub-Saharan Africa is increasing rapidly, and treatment remains challenging. Although the use of l-carnitine in treatment has received much attention, studies reporting on physiological l-carnitine levels in hypertensives are limited. Our aim was to determine physiological levels of l-carnitine and acylcarnitines in African and Caucasian men, and to investigate associations between ambulatory blood pressure (BP) and carnitine levels. Participants included 101 African and 101 Caucasian teachers. Ambulatory BP measurements were conducted, and l-carnitine and acylcarnitine levels determined. African men showed significantly higher systolic BP (p < 0.001), diastolic BP (p < 0.001) and l-carnitine levels (p = 0.01). In both ethnic groups, partial regression analyses revealed a positive association between BP and l-carnitine, although in Caucasians it was with systolic (r = 0.20, p = 0.045), and in Africans with diastolic BP (r = 0.23, p = 0.023). After adjusting for confounders, an independent positive association between systolic (R ² = 0.37, β = 0.12, p = 0.041) and diastolic BP (R ² = 0.39, β = 0.14, p = 0.018) and l-carnitine and long-chain acylcarnitines (R ² = 0.38, β = 0.17, p = 0.005 and R ² = 0.39, β = 0.15, p = 0.011) were found, independent of ethnicity. Physiological l-carnitine levels were not only higher in Africans than in Caucasians but also above the expected reference range. Despite promising results on l-carnitine (and its short-chain derivatives) in hypertension treatment regimens, our findings paradoxically show that elevated BP is significantly associated with higher physiological l-carnitine and long-chain acylcarnitine levels.     

Adsorbed phosphate additives for interrogating the nature of interparticles forces in kaolin clay slurries via rheological yield stress

Unimin’s kaolin clay slurry displayed a maximum yield stress that is not located at the point of zero charge or at low zeta potential. Adsorbed phosphate additives at sufficient concentration caused this yield stress to reduce to zero. The clear implication of these two results is that the particle interactions contributing to the maximum yield stress must be due to unlike charged or positive–negative charge attraction. The adsorbed negatively charged phosphate additives neutralised the positively charge sites of the clay particles causing the suspension to be completely dispersed and the yield stress to disappear. The monophosphate additive is less effective in dispersing the slurries. Based on charge concentration of additives, the pyrophosphate, triphosphate and polyphosphate appeared to be equally as effective in dispersing the clay slurries. The yield stress-DLVO force model that predicts a linear relationship between yield stress and square of zeta potential with a negative slope, is obeyed by the kaolin slurries with adsorbed phosphate additives. However, with the slurry without phosphate additive it displayed three linear relationships with negative and positive slopes. The negative slope relationships were located in the low and high zeta potential regions while the positive slope relationship was found in between these regions.     

Case-control study of mesothelioma in South Africa

BACKGROUND: South Africa has, uniquely, mined, transported, and used crocidolite, amosite, and chrysotile. A multicenter case-control study was done in South Africa to examine the details of asbestos exposure in cases and controls, and to calculate relative risks for level of certainty of asbestos exposure, nature of exposure (e.g., environmental, occupational) and fiber type. METHODS: Cases and controls (one cancer and one medical per case) were collected by six study centers from referral hospitals, and exposure information was collected by interviewing cases and controls in life. RESULTS: One hundred and twenty-three cases were accepted into the study. None had purely chrysotile exposure. Twenty-three cases had mined Cape crocidolite; three had mined amosite; and three Transvaal crocidolite plus amosite. A minimum of 22 of the cases had exclusively environmental exposure, 20 were from the NW Cape crocidolite mining area. The relative risks associated with environmental exposure in the NW Cape (crocidolite) were larger than for environmental exposure in the NE Transvaal (amosite and crocidolite): 21.9 vs. 7.1 and 50.9 vs. 12.0 for the cancer control and medical control datasets, respectively. CONCLUSIONS: The results confirm the importance of environmental exposure in the Cape crocidolite mining area, the relative paucity of cases linked to amosite, the rarity of chrysotile cases and are consistent with a fiber gradient in mesotheliomagenic potential for South African asbestos with crocidolite > amosite > chrysotile.     

Changes in the tocopherol content of almond,pecan and macadamia kernels during storage

The individual tocopherols present in almond, pecan and macadamia nuts were determined by HPLC. Changes in tocopherol content during 16-months' storage at 30°C and 55% relative humidity were related to keeping quality. The large amount of total tocopherols, mainly α-tocopherol, in almonds accounted for their good storage ability. Pecan nuts with less total tocopherols and mainly γ-tocopherol became rancid after 4 months' storage and macadamia nuts, with practically no tocopherols, were rancid after 2 months' storage. Total tocopherol content decreased in all nuts during storage, possibly as a result of its inhibitory function during auto-oxidation.     

Safety characterstics of the MARS nuclear plant

New design criteria in the field of small and medium sized nuclear reactors will be illustrated; particular consideration will be given to the reactor MARS (Multipurpose Advanced Reactor, Inherently Safe) now under development at the Department of Energetics, University of Rome.An analysis of plant behaviour during a Station Black-out accident has been performed using the computer program RELAP 5/Mod. 2.     

Intravenous immunoglobulin prophylaxis in neonates on artificial ventilation

The efficacy of the prophylactic use of intravenous immunoglobulin (Ig) was evaluated in a double-blind placebo-controlled trial of 21 pairs of ventilated neonates weighing more than 1,500 g. Each infant received 0.4 g/kg/day of intravenous Ig or a similar volume of placebo daily for 5 days. Criteria used to assess the efficacy of intravenous Ig were the number of infections, the duration of ventilation therapy and time to clinical recovery. There were no significant differences in the treated and placebo groups with regard to the frequency of positive blood cultures (28.6% and 14.3%), endotracheal cultures (57.1% and 66.7%) and abnormal white cell counts (52.4% and 57.1%). On entry to the study there was no significant difference in IgG levels between the treated (974.5 mg/dl; SD 575.3) and placebo groups (818 mg/dl; SD 516.9). However, on day 6 the treated group had a mean level of 1,400.3 mg/dl (SD 426.7) versus 710.9 mg/dl (SD 377.4) in the placebo group (P < 0.05). Clinical improvement occurred within 3 days in both groups. Ventilatory support was required for 11.8 days (SD 8.3) in the treated and 11.8 days (SD 7.3) in the placebo group. Both groups required 3-4 antibiotic treatments over a period of 14-15 days. Two patients died in the treated and 4 in the placebo group, with 1 infant in each group developing bronchopulmonary dysplasia. The patients who recovered did so within 14 days. Analyses of subgroups of patients with different diagnoses revealed no differences except a trend suggesting fewer infections in term babies treated with intravenous Ig. The organisms cultured in the intravenous Ig groups were Pseudomonas, Klebsiella, Escherichia coli and Staphylococcus and in the placebo group Pseudomonas, Klebsiella and Enterobacter. The above has shown that, except for a trend in the older neonates, intravenous Ig is not of prophylactic benefit in ventilated neonates. Newer adjuncts in immunotherapy such as hyperimmune gammaglobulin or monoclonal antibodies may prove of greater value in the treatment of neonatal sepsis.     

Analysis of the inducer-responsive CAR1 upstream activation sequence (UASI) and the factors required for its operation

Induced production of arginase (CAR1) enzyme activity and steady-state CAR1 mRNA in Saccharomyces cerevisiae requires wild-type ARG80/ARGRI and ARG81/ARGRII gene products. We demonstrate here that these gene products, along with that of the MCM1 gene, are required for the inducer-dependent UAS_I-A, UAS_I-B and UAS_I-C elements to function but they are not required for operation of inducer-independent CAR1 UAS_C1 or UAS_C2M. Through the use of single and multiple point mutations, the CAR1 UAS_I-B and UAS_I-C elements were demonstrated to be at least 23 bp in length. Moreover, simultaneous mutation of both ends of an elements gave stronger phenotypes than mutations at either end. The center of the element was more sensitive to mutation than were the ends.     

Automated serum peptide profiling using novel magnetic C18 beads off-line coupled to MALDI-TOF-MS

Serum peptide profiling by MS is an emerging approach for disease diagnosis and biomarker discovery. A magnetic bead‐based method for off‐line serum peptide capture coupled to MALDI‐TOF‐MS has been recently introduced. However, the reagents are not available to the general scientific community. Here, we developed a protocol for serum peptide capture using novel magnetic C18 beads, and automated the procedure on a high‐throughput magnetic particle processor. We investigated bead equilibration, peptide binding and peptide elution conditions. The method is evaluated in terms of peaks counts and reproducibility of ion intensities in control serum. Overall, the DynaBead‐RPC18‐based serum sample processing protocol reported here is reproducible, robust and allows for the detection of ?200 peptides at m/z 800–4000 of serum that was allowed to clot for 1 h. The average intra‐experiment %CV of normalized ion intensities for crude serum and 0.5% TFA/0.15% n‐octyl glucoside‐treated serum, respectively, were 12% (range 2–38%) and 10% (3–21%) and the inter‐experiment %CVs were 24% (10–53%) and 31% (10–59%). Importantly, this method can be used for serum peptide profiling by anyone in possession of a MALDI‐TOF instrument. In conjunction with the KingFisher® 96, the whole serum peptide capture procedure is high‐throughput (?20 min per isolation of 96 samples in parallel), thereby facilitating large‐scale disease profiling studies.