Source inference of exogenous gamma-hydroxybutyric acid (GHB) administered to humans by means of carbon isotopic ratio analysis: novel perspectives regarding forensic investigation and intelligence issues.

γ-Hydroxybutyric acid (GHB) is an endogenous short-chain fatty acid popular as a recreational drug due to sedative and euphoric effects, but also often implicated in drug-facilitated sexual assaults owing to disinhibition and amnesic properties. Whilst discrimination between endogenous and exogenous GHB as required in intoxication cases may be achieved by the determination of the carbon isotope content, such information has not yet been exploited to answer source inference questions of forensic investigation and intelligence interests. However, potential isotopic fractionation effects occurring through the whole metabolism of GHB may be a major concern in this regard. Thus, urine specimens from six healthy male volunteers who ingested prescription GHB sodium salt, marketed as Xyrem(®), were analysed by means of gas chromatography/combustion/isotope ratio mass spectrometry to assess this particular topic. A very narrow range of δ(13)C values, spreading from -24.810/00 to -25.060/00, was observed, whilst mean δ(13)C value of Xyrem(®) corresponded to -24.990/00. Since urine samples and prescription drug could not be distinguished by means of statistical analysis, carbon isotopic effects and subsequent influence on δ(13)C values through GHB metabolism as a whole could be ruled out. Thus, a link between GHB as a raw matrix and found in a biological fluid may be established, bringing relevant information regarding source inference evaluation. Therefore, this study supports a diversified scope of exploitation for stable isotopes characterized in biological matrices from investigations on intoxication cases to drug intelligence programmes.

A note on the stading stock and production of microplankton off the coast of Peru as determined by particle counting

Analiza el método de conteo de particulas usado para determinar las distribución de particulas suspendidas en un rango de 2 -102 um

Small RNA as global regulator of carbon catabolite repression in Pseudomonas aeruginosa.

In the metabolically versatile bacterium Pseudomonas aeruginosa, the RNA-binding protein Crc is involved in catabolite repression of a range of degradative genes, such as amiE (encoding aliphatic amidase). We found that a CA-rich sequence (termed CA motif) in the amiE translation initiation region was important for Crc binding. The small RNA CrcZ (407 nt) containing 5 CA motifs was able to bind the Crc protein with high affinity and to remove it from amiE mRNA in vitro. Overexpression of crcZ relieved catabolite repression in vivo, whereas a crcZ mutation pleiotropically prevented the utilization of several carbon sources. The sigma factor RpoN and the CbrA/CbrB two-component system, which is known to maintain a healthy carbon-nitrogen balance, were necessary for crcZ expression. During growth on succinate, a preferred carbon source, CrcZ expression was low, resulting in catabolite repression of amiE and other genes under Crc control. By contrast, during growth on mannitol, a poor carbon source, elevated CrcZ levels correlated with relief of catabolite repression. During growth on glucose, an intermediate carbon source, CrcZ levels and amiE expression were intermediate between those observed in succinate and mannitol media. Thus, the CbrA-CbrB-CrcZ-Crc system allows the bacterium to adapt differentially to various carbon sources. This cascade also regulated the expression of the xylS (benR) gene, which encodes a transcriptional regulator involved in benzoate degradation, in an analogous way, confirming this cascade's global role.

Establishment of new crops for the production of natural rubber.

Natural rubber is a unique biopolymer of strategic importance that, in many of its most significant applications, cannot be replaced by synthetic alternatives. The rubber tree Hevea brasiliensis is the almost exclusive commercial source of natural rubber currently and alternative crops should be developed for several reasons, including: a disease risk to the rubber tree that could potentially decimate current production, a predicted shortage of natural rubber supply, increasing allergic reactions to rubber obtained from the Brazilian rubber tree and a general shift towards renewables. This review summarizes our knowledge of plants that can serve as alternative sources of natural rubber, of rubber biosynthesis and the scientific gaps that must be filled to bring the alternative crops into production.

Growth, crown structure and seed production of birch seedlings, grafts and micropropagated plants

Summary

Production of calves following nonsurgical transfer of fresh and refrigerated bovine demi-embryos

Selostus: Vasikoiden tuottaminen tuoreilla ja kylmäsäilytetyillä halkaistuilla alkioilla

Production of Pseudomonas aeruginosa Intercellular Small Signaling Molecules in Human Burn Wounds

Pseudomonas aeruginosa has developed a complex cell-to-cell communication system that relies on low-molecular weight excreted molecules to control the production of its virulence factors. We previously characterized the transcriptional regulator MvfR, that controls a major network of acute virulence functions in P. aeruginosa through the control of its ligands, the 4-hydroxy-2-alkylquinolines (HAQs)-4-hydroxy-2-heptylquinoline (HHQ) and 3,4-dihydroxy-2-heptylquinoline (PQS). Though HHQ and PQS are produced in infected animals, their ratios differ from those in bacterial cultures. Because these molecules are critical for the potency of activation of acute virulence functions, here we investigated whether they are also produced during human P. aeruginosa acute wound infection and whether their ratio is similar to that observed in P. aeruginosa-infected mice. We found that a clinically relevant P. aeruginosa isolate produced detectable levels of HAQs with ratios of HHQ and PQS that were similar to those produced in burned and infected animals, and not resembling ratios in bacterial cultures. These molecules could be isolated from wound tissue as well as from drainage liquid. These results demonstrate for the first time that HAQs can be isolated and quantified from acute human wound infection sites and validate the relevance of previous studies conducted in mammalian models of infection.

In vitro production of cattle blastocysts in chemically defined medium with or without insulin supplementation

Selostus: Insuliinin vaikutus naudan blastokystien tuottamiseen in vitro kemiallisesti tunnetussa liuoksessa

The evolution of recent research on Catalan literature through the production of PhD theses: a bibliometric and social network analysis

Introduction. This paper studies the situation of research on Catalan literature between 1976 and 2003 by carrying out a bibliometric and social network analysis of PhD theses defended in Spain. It has a dual aim: to present interesting results for the discipline and to demonstrate the methodological efficacy of scientometric tools in the humanities, a field in which they are often neglected due to the difficulty of gathering data. Method. The analysis was performed on 151 records obtained from the TESEO database of PhD theses. The quantitative estimates include the use of the UCINET and Pajek software packages. Authority control was performed on the records. Analysis. Descriptive statistics were used to describe the sample and the distribution of responses to each question. Sex differences on key questions were analysed using the Chi-squared test. Results. The value of the figures obtained is demonstrated. The information obtained on the topic and the periods studied in the theses, and on the actors involved (doctoral students, thesis supervisors and members of defence committees), provide important insights into the mechanisms of humanities disciplines. The main research tendencies of Catalan literature are identified. It is observed that the composition of members of the thesis defence committees follows Lotka's Law. Conclusions. Bibliometric analysis and social network analysis may be especially useful in the humanities and in other fields which are lacking in scientometric data in comparison with the experimental sciences.

Non invasive transcutaneous blood carboxyhemoglobine level: reliability in victims of carbon monoxide poisoning

Introduction: Carbon monoxide (CO) poisoning is one of the mostcommon causes of fatal poisoning. Symptoms of CO poisoning arenonspecific and the documentation of elevated carboxyhemoglobin(HbCO) levels in arterial blood sample is the only standard ofconfirming suspected exposure. The treatment of CO poisoning requiresnormobaric or hyperbaric oxygen therapy, according to the symptomsand HbCO levels. A new device, the Rad-57 pulse CO-oximeter allowsnoninvasive transcutaneous measurement of blood carboxyhemoglobinlevel (SpCO) by measurement of light wavelength absorptions.Methods: Prospective cohort study with a sample of patients, admittedbetween October 2008 - March 2009 and October 2009 - March 2010,in the emergency services (ES) of a Swiss regional hospital and aSwiss university hospital (Burn Center). In case of suspected COpoisoning, three successive noninvasive measurements wereperformed, simultaneously with one arterial blood HbCO test. A controlgroup includes patients admitted in the ES for other complaints (cardiacinsufficiency, respiratory distress, acute renal failure), but necessitatingarterial blood testing. Informed consent was obtained from all patients.The primary endpoint was to assess the agreement of themeasurements made by the Rad-57 (SpCO) and the blood levels(HbCO).Results: 50 patients were enrolled, among whom 32 were admittedfor suspected CO poisoning. Baseline demographic and clinicalcharacteristics of patients are presented in table 1. The median age was37.7 ans ± 11.8, 56% being male. Median laboratory carboxyhemoglobinlevels (HbCO) were 4.25% (95% IC 0.6-28.5) for intoxicated patientsand 1.8% (95% IC 1.0-5.3) for control patients. Only five patientspresented with HbCO levels >= 15%. The results disclose relatively faircorrelations between the SpCO levels obtained by the Rad-57 and thestandard HbCO, without any false negative results. However, theRad-57 tend to under-estimate the value of SpCO for patientsintoxicated HbCO levels >10% (fig. 1).Conclusion: Noninvasive transcutaneous measurement of bloodcarboxyhemoglobin level is easy to use. The correlation seems to becorrect for low to moderate levels (<15%). For higher values, weobserve a trend of the Rad-57 to under-estimate the HbCO levels. Apartfrom this potential limitation and a few cases of false-negative resultsdescribed in the literature, the Rad-57 may be useful for initial triageand diagnosis of CO.

Production of fungal volatile organic compounds in bedding materials

Selostus: Haihtuvien orgaanisten yhdisteiden muodostuminen kuivikkeissa

Enzymatic activity and mineralization of carbon and nitrogen in soil cultivated with coffee and green manures

There are great concerns about degradation of agricultural soils. It has been suggested that cultivating different plant species intercropped with coffee plants can increase microbial diversity and enhance soil sustainability. The objective of this study was to evaluate enzyme activity (urease, arylsulfatase and phosphatase) and alterations in C and N mineralization rates as related to different legume cover crops planted between rows of coffee plants. Soil samples were collected in a field experiment conducted for 10 years in a sandy soil in the North of Paraná State, Brazil. Samples were collected from the 0-10 cm layer, both from under the tree canopy and in-between rows in the following treatments: control, Leucaena leucocephala, Crotalaria spectabilis, Crotalaria breviflora, Mucuna pruriens, Mucuna deeringiana, Arachis hypogaea and Vigna unguiculata. The soil was sampled in four stages of legume cover crops: pre-planting (September), after planting (November), flowering stage (February) and after plant residue incorporation (April), from 1997 to 1999. The green manure species influenced soil enzyme activity (urease, arylsulfatase and phosphatase) and C and N mineralization rates, both under the tree canopy and in-between rows. Cultivation of Leucaena leucocephala increased acid phosphatase and arilsulfatase activity and C and N mineralization both under the tree canopy and in-between rows. Intercropped L. leucocephala increased urease activity under the tree canopy while C. breviflora increased urease activity in-between rows.