Rapid communication: a vegetable oil extract restores redox status in fibroblasts from psoriatic patients.

Psoriasis is an inflammatory skin disease that affects 2-5% of the worldwide population. It is a chronic immune-mediated hyperproliferative inflammatory skin disease of unknown etiology, characterized by the appearance of sore patches of thick, red skin with silvery scales.

Nitrite and nitrate as electron acceptors for biological sulphide oxidation.

Autotrophic denitrification with sulphide using nitrate (R1) and nitrite (R2) as electron acceptor was investigated at bench scale. Different solids retention times (SRT) (5 and 20 d) have been tested in R1 while R2 was operated at SRT=13 d. The results indicated that the process allows complete sulphide removal to be achieved in all tested conditions. Tested sulphide loads were estimated from the H2S produced in a pilot-scale anaerobic digester treating vegetable tannery primary sludge; nitrogen loads originated from the nitrification of the supernatant. Average nitrogen removal efficiencies higher than 80% were observed in all the tested conditions once steady state was reached. A maximum specific nitrate removal rate equal to 0.35 g N-NO3- g VSS(-1) d(-1) was reached in R1. Due to sulphide limitation, incomplete denitrification was observed and nitrite and thiosulphate tend to accumulate especially in the presence of variable environmental conditions in both R1 and R2. Lower SRT caused higher NO2accumulated/NO3reduced ratios (0.22 and 0.24, with SRT of 5 d and 20 d, respectively) using nitrate as electron acceptor in steady-state condition. Temperature decrease caused sudden NO2accumulated/NO3reduced ratio increase in R1 and NO2- removal decrease in R2.

Ionospheric redistribution during geomagnetic storms.

[1]The abundance of plasma in the daytime ionosphere is often seen to grow greatly during geomagnetic storms. Recent reports suggest that the magnitude of the plasma density enhancement depends on the UT of storm onset. This possibility is investigated over a 7year period using global maps of ionospheric total electron content (TEC) produced at the Jet Propulsion Laboratory. The analysis confirms that the American sector exhibits, on average, larger storm time enhancement in ionospheric plasma content, up to 50% in the afternoon middle-latitude region and 30% in the vicinity of the high-latitude auroral cusp, with largest effect in the Southern Hemisphere. We investigate whether this effect is related to the magnitude of the causative magnetic storms. Using the same advanced Dst index employed to sort the TEC maps into quiet and active (Dst<-100 nT) sets, we find variation in storm strength that corresponds closely to the TEC variation but follows it by 3-6h. For this and other reasons detailed in this report, we conclude that the UT-dependent peak in storm time TEC is likely not related to the magnitude of external storm time forcing but more likely attributable to phenomena such as the low magnetic field in the South American region. The large Dst variation suggests a possible system-level effect of the observed variation in ionospheric storm response on the measured strength of the terrestrial ring current, possibly connected through UT-dependent modulation of ion outflow.

Venous thromboembolism and hypercoagulability in splenectomized patients with thalassaemia intermedia.

Thromboembolic phenomena have been described in patients with thalassaemia intermedia and major, although there are relatively few epidemiological data on the overall frequency of these complications. To obtain more insight into the risk and mechanism of venous thromboembolism in thalassaemia, the aims of this study were: (i) to establish retrospectively the prevalence of thromboembolic events in a large group of adults with thalassaemia intermedia and major during a follow up period of 10 years; (ii) to measure in subgroups of these patients sensitive markers of activation of coagulation and fibrinolysis enzymes; and (iii) to look for possible procoagulant mechanisms. A high prevalence of thromboembolic events was found, particularly in splenectomized patients with thalassaemia intermedia (29%). These patients had high plasma levels of markers of coagulation and fibrinolysis activation. Furthermore, thalassaemic red cells and erythroid precursors from splenectomized patients with thalassaemia intermedia had an enhanced capacity to generate thrombin. To evaluate the role of splenectomy per se on procoagulant activity, we evaluated the capacity to form thrombin in healthy individuals who had been splenectomized for trauma. They produced the same amount of thrombin as non-splenectomized controls. In conclusion, the results of this study show the existence of a hypercoagulable state in splenectomized patients with thalassaemia intermedia and that their red and erythroid cells are capable of acting as activated platelets in thrombin generation.

Drug impurities: problems and regulations.

The matter of impurities is a frequently debated issue, mainly focused on the validation of the analytical methods and on the toxicology of potential impurities. In the first part of the review, the classification, the source and the chemical aspects of impurities are briefly considered according to the current international regulations. A special attention is given to the analytical control, in both qualitative and quantitative terms, of unexpected impurities arising from changes in the manufacturing process or by degradation. The thresholds for identification and qualification of impurities in new drug substances and in new drug products are examined together with the safety studies, when required. Finally, the acceptance limits for four classes of residual solvents are also reported.

Forensic evaluation of HUMCD4: an Italian database.

The YTTTC pentanucleotide short tandem repeat polymorphism HumCD4 was studied in an Italian population sample. PCR products were compared to an allelic ladder by manual PAGE and silver staining. A total of 6 alleles ranging from 5 to 12 repeats were represented in the analysed sample, of which 3 alleles (10, 6 and 5 repeats) were predominant and displayed a combined frequency of 0.91. Successful amplification was obtained from different sources such as blood and urine stains, teeth and paraffin embedded tissues. Results were also determined in cases of severely degraded DNA. We consider that the HUMCD4 polymorphism may be a useful tool for individual identification, paternity testing, population studies and have also employed this locus to monitor engraftment of bone marrow transplantation.

DNA typing from human faeces.

A method has been developed for the forensic analysis of faeces by DNA amplification and direct sequencing of a polymorphic segment of mitochondrial DNA. Starting from as little as 10 mg wet weight of faeces, DNA was extracted by a variety of protocols and amplified using primers specific to hypervariable region 1 of the mitochondrial control region. The resulting amplification products were sequenced in solid phase using an automated DNA sequencer. In total, mtDNA sequences were generated from the faeces of nine Caucasians and compared with sequences generated from their respective blood samples. Sequences of faeces and blood samples from the same individual were identical in every case, but a range of 1-10 nucleotide differences was observed between individuals, with an average sequence variation of approximately 4.88 per 400 bp. Of the various extraction protocols assessed in this study, greatest success rates were achieved using magnetisable beads to bind and purify the DNA. STR analysis of DNA extracted from faeces was not routinely possible.

Analysis of a short tandem repeat locus on chromosome 19 (D19S253).

A tetranucleotide tandem repeat locus on chromosome 19 (D19S253) was analysed. PCR products were detected by denaturing polyacrylamide gels with fluorescent-based technology. This study has confirmed a polymorphism with 9 alleles ranging from 209 to 241 bp with a simple repeat structure arranged from 7 to 15 repeats. Family studies confirmed mendelian inheritance of alleles. The efficiency on DNA extracted from bloodstains and cigarette butts has been evaluated. The protocol has shown sensitivity and reproducibility.

HLA-DQA1 and amelogenin coamplification: a handy tool for identification.

A protocol for HLA-DQA1 and gender identification by single amplification is described. The use of the commercial HLA-DQA1 amplification kit (Perkin Elmer) permits a positive response for sex determination by adding primers for a short sequence on the first intron of Amelogenin gene. The suggested amplification protocol results in PCR products easily and clearly detectable on ethidium bromide stained agarose gel or silver stained polyacrylamide gel. In both gels the HLA-DQA1 observations at 242-239 bp are accomplished with a single band at 106 bp in females and a doublet 112-106 bp in males. HLA-DQA1 reverse dot-blot hybridization is unaffected by the presence of X and Y amplified fragments.

Individual identification of flood victims by DNA polymorphisms and autopsy findings.

On September 23rd 1993 Genova was flooded by heavy rainstorms and 4 people disappeared, including an elderly couple. Four days later a partially skeletonized body was found floating near the coast. No visual identification was possible. Autopsy findings were consistent with the medical history of a possible victim. DNA was extracted from a muscle sample and compared to paraffin embedded prostatic gland fragment taken by surgery. A positive identification could be made. On October 11th the body of a decomposed and partially skeletonized female was found. The visual identification was also uncertain and no clinical records were available. A blood sample from the son was obtained for maternal identification by the polymerase chain reaction.

Forensic application of a rapid and quantitative DNA sex test by amplification of the X-Y homologous gene amelogenin.

Gender identification of forensic samples was determined by amplifying a segment of the X-Y homologous gene amelogenin. Using a single pair of primers spanning part of the first intron, 106 bp and 112 bp PCR products were generated from the X and Y homologues respectively, which were then resolved by agarose gel electrophoresis. This test enabled as little as 20 pg of DNA from severely degraded bones to be amplified and typed in a single tube reaction. Furthermore, using dye-labelled primers, it was possible to quantitate, by automated fluorescence detection, the relative yields of X and Y-specific PCR products generated from mixtures of male and female DNA. The versatility of this sex test was further demonstrated by co-amplifying with the HLA-DQA1 Amplitype kit in a combined gender/identity DNA test.

A rapid and quantitative DNA sex test: fluorescence-based PCR analysis of X-Y homologous gene amelogenin.

A rapid, simple and reliable sex test that entails PCR amplification of a segment of the X-Y homologous gene amelogenin has been developed. We used a single pair of primers spanning part of the first intron which generated 106-bp and 112-bp PCR products from the X and Y homologues, respectively, that can be analyzed simply by agarose gel electrophoresis. Less than 1 ng of template DNA is required for gender assignment, and the test has been automated by the fluorescent tagging of the PCR products that are then quantitated during electrophoresis by automated fluorescence-detection technology. Quantitation enables sex chromosome aneuploidy to be determined, and the amelogenin intron sequence can also be co-amplified with several highly polymorphic microsatellite loci, thereby providing a combined gender/identity DNA test.

HLA-DQA1 allele and genotype frequencies in a northern Italian population.

HLA-DQA1 typing of 227 randomly selected Northern Italian people by the use of polymerase chain reaction are reported. The combined use of commercial Amplitype HLA-DQalpha system and four sequence-specific oligonucleotide probes allows the definition of 8 alleles and 36 genotypes, arranged according to World Health Organisation nomenclature. Seven of these genotypes are not observed among the analyzed samples. Allele frequencies range from 1.5 to 35.7% and genotype observations do not deviate significantly from Hardy-Weinberg equilibrium; observed heterozygosity is 0.8238 with an allelic diversity value of 0.79 and the power of discrimination is 0.925. Our Italian population sample shows differences from other Caucasian samples both for allele and genotype frequencies. This locus typing for the 8 defined alleles provides a rapid and sensitive method in individual identification and paternity investigation.