A limited survey of aflatoxin B1 contamination in Indonesian palm kernel cake and copra meal sampled from batches

Samples from large (100–200 tons) batches of palm kernel cake (PKC, n?=?20) and copra meal (CM, n?=?13) were collected at production facilities of four Indonesian feed mill manufacturers and analysed for aflatoxin B₁ (AFB₁) by ELISA. Recoveries using spiked samples ranged from 86 to 113 %, with relative standard deviations of <9 % (PKC) and <6 % (CM). All batches were positive for AFB₁: in PKC, at levels of 5.8–93.1 μg/kg (mean 49 μg/kg), and in CM, at levels of 1.1–147 μg/kg (mean 38.1 μg/kg). AFB₁ levels were, in most batches, below the maximum level (100 μg/kg) recommended by the National Standardisation Agency, Republic of Indonesia. However, about half of the batches exceeded both the European Union and USA regulations for AFB₁ in animal feed. In conclusion, serious efforts are necessary to control production, storage and shipment of palm kernel cake and copra meal for feed purposes, and clearly not only for products intended for export but also to reduce AFB₁ levels in domestic Indonesian feed.     

Influence of long-term diesel fuel pollution on nitrite-oxidising activity and population size of nitrobacter spp in soil

Previous investigations have shown that ammonia oxidation is not inhibited by diesel fuel in a soil with a long history of contamination contrary to a non-contaminated soil. As a consequence, ammonia oxidation does not constitute a limited step in nitrification process (Appl. Environ. Microbiol. 65 (1999) 4008). Moreover, this type of soil also has had the opportunity to develop an abundant microbial population able to metabolise the diesel hydrocarbons. Whether the properties of soil with a long history of diesel fuel contamination may affect the activity of nitrite-oxidising bacteria was investigated. It was observed that re-exposure of soil to diesel fuel apparently stimulated the proliferation of nitrite-oxidising bacteria, as determined by most probable number (MPN) culture technique and MPN-polymerase chain reaction technique. The potential of nitrite-oxidising activity in soil treated with diesel fuel was about 4 times higher than in the control without addition. In the presence of diesel fuel and ammonium, the potential nitrite-oxidising activity was 40% higher than in presence of ammonium only. However, in the presence of hydrocarbon only, low proliferation of Nitrobacter was observed, probably because the heterotrophic bacteria were strongly limited by lack of nitrogen and did not produce sufficient organic metabolites that could be used by the Nitrobacter cells.     

Whole cell nuclear magnetic resonance characterization of two photochemically active states of the photosynthetic reaction center in heliobacteria

Applying photo-CIDNP (photochemically induced dynamic nuclear polarization) MAS (magic-angle spinning) nuclear magnetic resonance to whole cells of Heliobacillus (Hb.) mobilis, we demonstrate that heliobacterial reaction centers are operational in two different states as indicated by the occurrence of a light-induced spin-correlated radical pair. A culture maintained anaerobically is called "Braunstoff" (German for "brown substance"). After exposure to oxygen, Braunstoff is converted to "Grünstoff" ("green substance") as indicated by a color change due to the conversion of BChl g to Chl a(F). It is shown that electron transfer occurs symmetrically via both branches of cofactors in both forms. The donor and acceptor cofactors remain identical and unchanged upon conversion, while the intermediate accessory cofactors are transformed from BChl g to Chl a(F). The donor triplet state in Braunstoff is localized on the special pair donor and lives for 100 μs, demonstrating the absence of nearby carotenoids. In Grünstoff, the donor triplet becomes mobile and appears to be formed on an accessory cofactor.     

Unsuccessful search for DNA transfer from transgenic plants to bacteria in the intestine of the tobacco horn worm, <Emphasis Type="Italic">Manduca sexta</Emphasis>

DNA transfer from transgenic plants to native intestinal bacteria and introduced Acinetobacter BD413 was assessed in the gut of the tobacco horn worm (Manduca sexta). The marker was kanamycin resistance gene (nptII), and tobacco carrying the nptII gene in the chloroplasts served as the donor. We detected neither whole gene transfer to native bacteria, nor transfer of fragments of nptII to Acinetobacter, using a marker exchange assay. This negative result was attributed to a heat-labile activity that degraded DNA in the feces, probably DNAase. Nevertheless, a few intact leaf cells survived transit through the gut, and DNA extracted from feces did transform Acinetobacter, albeit at lower frequencies than DNA extracted from leaves.     

Effects of the FcRn developmental pharmacology on the pharmacokinetics of therapeutic monoclonal IgG antibody in pediatric subjects using minimal physiologically-based pharmacokinetic modelling

The aim of this study was to investigate neonatal Fc receptor (FcRn) concentration developmental pharmacology in adult and pediatric subjects using minimal physiologically-based pharmacokinetic (mPBPK) modelling. Three types of pharmacokinetic (PK) data for three agents (endogenous/exogenous native IgG, bevacizumab and palivizumab) were used. The adult group contained six subjects with weights from 50 to 100 kg. For pediatric subjects, seven age groups were assumed, with five subjects each having the weight of 95%, 75%, 50%, 25% and 5% percentile of the population. A first evidence-based rating system to evaluate the quality of the source data used to derive pediatric-specific mPBPK model parameter was proposed. A stepwise approach was used to examine the best combination of age/weight effect on the parameters of the mPBPK model in adult and pediatric subjects. IgG synthesis rate (K_syn), extravasation rate (ER) and FcRn were fitted simultaneously to the PK of bevacizumab and native-IgG in both adult and pediatric. All fitting showed good fits based on the graphs and the coefficient of variation of the fitted parameters (< 50%). Estimated weight-normalized K_syn increased while weight-normalized FcRn and ER decreased with increasing age. The age and weight effect on FcRn were successfully estimated from the data. The final mPBPK model developed with native IgG and bevacizumab was able to predict the PK of palivizumab in pediatric subjects. Implementation of the mPBPK model enables us to analyze the relationships of age, weight, FcRn, ER and K_syn in both adult and pediatric subject. This information may benefit the understanding of complex interaction between the FcRn developmental pharmacology and PK parameters, and improve the prediction of the antibody disposition in pediatric subjects.     

Acidic hyaluronidase activity is present in mouse sperm and is reduced in the absence of SPAM1: Evidence for a role for hyaluronidase 3 in mouse and human sperm

The molecular mechanisms underlying sperm penetration of the physical barriers surrounding the oocyte have not been completely delineated. Although neutral‐active or “reproductive” hyaluronidases (hyases), exemplified by Sperm Adhesion Molecule 1 (SPAM1), are thought to be responsible for hyaluronan digestion in the egg vestments and for sperm‐zona binding, their roles in mouse sperm have been recently questioned. Here we report that acidic “somatic” Hyaluronidase 3 (HYAL3), a homolog of SPAM1 with 74.6% structural similarity, exists in two isoforms in human (～47 and ～55 kDa) and mouse (～44 and ～47 kDa) sperm, where it resides on the plasma membrane over the head and midpiece. Mouse isoforms are differentially distributed in the soluble (SAP), membrane (MBP), and acrosome‐reacted (AR) fraction where they are most abundant. Comparisons of zymography of Hyal3 null and wild‐type (WT) AR and MBP fractions show significant HYAL3 activity at pH 3 and 4, and less at pH 7. At pH 4, a second acid‐active hyase band at ～57 kDa is present in the AR fraction. HYAL3 activity was confirmed using immunoprecipitated HYAL3 and spectrophotometry. In total proteins, hyase activity was higher at pH 6 than at 4, where Spam1 nulls had significantly (P < 0.01) diminished activity implicating an acidic optima for murine SPAM1. Although fully fertile, Hyal3 null sperm showed delayed cumulus penetration and reduced acrosomal exocytosis. HYAL3 is expressed in epididymal tissue/fluid, from where it is acquired by caudal mouse sperm in vitro. Our results reveal concerted activity of both neutral‐ and acid‐active hyaluronidases in sperm. Mol. Reprod. Dev. 77: 759–772, 2010. © 2010 Wiley‐Liss, Inc.     

Body temperature and thermoregulation of Komodo dragons in the field

Komodo dragons from hatchlings (≈0.1 kg) to adults (≤80 kg) express the full magnitude of varanid species size distributions. We found that all size groups of dragons regulated a similar preferred body temperature by exploiting a heterogeneous thermal environment within savanna, forest and mangrove habitats. All dragons studied, regardless of size, were able to regulate a daytime active body temperature within the range 34–35.6 °C for 5.1–5.6 h/day. The index of effectiveness of thermoregulation (a numerical rating of thermoregulatory activity) was not different among size groups of dragons. However, the index of closeness of thermoregulation, which rates the variability of body temperature, suggests a greater precision for regulating a preferred body temperature for medium compared to small and large dragons. Reference copper cylinders simulating small, medium and large Komodo dragons heated and cooled at the same rate, whereas actual dragons of all size groups heated faster than they cooled. Larger dragons heated and cooled more slowly than smaller ones. The mean operative environmental temperatures of copper cylinders representing medium sized dragons were 42.5, 32.0 and 29.4° C for savannah, forest and mangrove habitats, respectively. The index for average thermal quality of a habitat as measured by the absolute difference between operative environmental temperature and the dragon’s thermal range suggests the forest habitat offers the highest thermal quality to dragons and the savannah the lowest. The percent of total daytime that the operative environmental temperature was within the central 50% of the body temperatures selected by dragons in a thermal gradient (Phillips, 1984) was 45%, 15%, and 9% for forest, mangrove and savannah, respectively. Forest habitat offers the most suitable thermal environment and provides the greatest number of hours with conditions falling within the dragon’s thermal activity zone.     

Row for Your Life: A Century of Mortality Follow-Up of French Olympic Rowers

Background/Aim

Strenuous endurance training required to participate in the highest sports level has been associated with deleterious effects on elite athletes'' health and cardiac abnormalities. We aimed to describe overall mortality and main causes of deaths of male French rowers participating in at least one Olympic Game (OG) from 1912 to 2012 in comparison with the French general population.

Methods

Identity information and vital status of French Olympic rowers were validated by National sources from 1912 to 2013 (study''s endpoint) among 203 rowers; 52 out of 255 (20.3%) were excluded because their vital statuses could not be confirmed. Main causes of deaths were obtained from the National registry from 1968 up to 2012. Overall and disease-specific mortalities were calculated through standardised mortality ratios (SMRs) with its 95% confidence intervals (CIs). The overall mortality was calculated for the whole rowers'' cohort (PT) and for two periods apart: (P1) including rowers from 1912 to 1936 OG, a cohort in which all rowers have deceased and (P2) considering rowers from 1948 to 2012 OG.

Results

Among the 203 rowers analysed, 46 died before the study''s endpoint, mainly from neoplasms (33%), cardiovascular diseases (21%) and external causes (18%). PT demonstrates a significant 42% lower overall mortality (SMR: 0.58, 95% CI: 0.43–0.78, p<0.001), P1 a 37% reduction (SMR: 0.63, 95% CI: 0.43–0.89, p = 0.009) and P2 a 60% reduction (SMR: 0.40, 95% CI: 0.23–0.65, p<0.001) compared with their compatriots. Mortality due to cardiovascular diseases is significantly reduced (SMR: 0.41, 95% CI: 0.16–0.84, p = 0.01) among rowers.

Conclusions

French Olympic rowers benefit of lower overall mortality compared with the French general population. Among rowers'' main causes of death, cardiovascular diseases are reduced in relation to their compatriots. Analytical studies with larger samples are needed to understand the reasons for such reductions.