In planta expression of a mature Der p 1 allergen isolated from an Italian strain of Dermatophagoides pteronyssinus

European (Dermatophagoides pteronyssinus) and American (Dermatophagoides farinae) house dust mite species are considered the most common causes of asthma and allergic symptoms worldwide. Der p 1 protein, one of the main allergens of D. pteronyssinus, is found in high concentration in mites faecal pellets, which can became easily airborne and, when inhaled, can cause perennial rhinitis and bronchial asthma. Here we report the isolation of the Der p 1 gene from an Italian strain of D. pteronyssinus and the PVX-mediated expression of its mature form (I-rDer p 1) in Nicotiana benthamiana plants. Human sera from characterized allergic patients were used for IgE binding inhibition assays to test the immunological reactivity of I-rDer p 1 produced in N. benthamiana plants. The binding properties of in planta produced I-rDer p 1 versus the IgE of patients sera were comparable to those obtained on Der p 1 preparation immobilized on a microarray. In this paper we provide a proof of concept for the production of an immunologically active form of Der p 1 using a plant viral vector. These results pave the way for the development of diagnostic allergy tests based on in planta produced allergens.

Tracing the biological origin of animal glues used in paintings through mitochondrial DNA analysis

We report the development of a suitable protocol for the identification of the biological origin of binding media on tiny samples from ancient paintings, by exploitation of the high specificity and high sensitivity offered by the state-of-the art DNA analysis. In particular, our aim was to molecularly characterize mitochondrial regions of the animal species traditionally employed for obtaining glues. The model has been developed using aged painting models and then tested to analyze the organic components in samples from the polychrome terracotta Madonna of Citerna by Donatello (1415-1420), where, by GC-MS and FTIR spectroscopy, animal glues and siccative oils were identified. The results obtained are good in terms of both sensibility and specificity of the method. First of all, it was possible to confirm that Donatello used animal glue for the preparation of the painted layers of the Madonna of Citerna and, specifically, glue derived from Bos taurus. Data obtained from sequencing confirm that each sample contains animal glue, revealing that it was mostly prepared from two common European taurine lineages called T2 and T3. There is one remarkable exception represented by one sample which falls into a surviving lineage of the now extinct European aurochs.

Exposure to cadmium-contaminated soils increases allergenicity of Poa annua L. pollen

BACKGROUND

Pollution is considered as one main cause for the increase of allergic diseases. Air pollutants may cause and worsen airway diseases and are probably able to make pollen allergens more aggressive. Previous studies looked at traffic-related air pollution, but no data about the effects of polluted soils on pollen allergens are available. We aimed to assess the effects of plant exposure to cadmium-contaminated soil on allergenicity of the annual blue grass, Poa annua L, pollen.

METHODS

Poa plants were grown in soil contaminated or not contaminated (control) with cadmium. At flowering, mature pollen was analyzed by microscopy, to calculate the percentage of pollen grains releasing cytoplasmic granules, and by proteomic techniques to analyze allergen proteins. Allergens were identified by sera from grass pollen-allergic patients and by mass spectrometry.

RESULTS

Pollen from Cd-exposed plants released a higher amount of allergenic proteins than control plants. Moreover, Cd-exposed pollen released allergens-containing cytoplasmic grains much more promptly than control pollen. Group 1 and 5 allergens, the major grass pollen allergens, were detected both in control and Cd-exposed extracts. These were the only allergens reacting with patient's sera in control pollen, whereas additional proteins strengthening the signal in the gel region reacting with patient's sera were present in Cd-exposed pollen. These included a pectinesterase, a lipase, a nuclease, and a secretory peroxydase. Moreover, a PR3 class I chitinase-like protein was also immunodetected in exposed plants.

CONCLUSION

Pollen content of plants grown in Cd-contaminated soils is more easily released in the environment and also shows an increased propensity to bind specific IgE.

Radiolytically induced one-electron reduction of artemisinin in H2O/ethanol (1:1 v/v) solution: a pulse radiolysis study

The aim was to obtain information on the one-electron reduction of the antimalarial natural drug artemisinin (ART). The pulse radiolysis of ART in H(2)O/ethanol (EtOH) (1:1 v/v) solution was studied in the absence and presence of the so-called redox indicators N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD), Fe(CN)6(4-), 1,1'-dimethyl-4,4'-bipyridinium dichloride (methyl viologen, MV(2+)) and Fe(CN)6(3-). In an argon-purged solution, ART reacts with solvated electrons (es(-)) with k=4.4 x 10(9) dm(3) mol(-1) s(-1) generating an absorption band rising in the ultraviolet region similar to the spectrum of the CH3(*)CHOH radical. The species originating from the reaction between ART and es(-) do not show any appreciable reactivity toward Fe(CN)6(4-), TMPD, MV(2+) and Fe(CN)6(3-). The experiments performed in the presence of ART and MV(2+) have provided strong support to the idea that the first species obtained from the addition of the electron, which is believed to occur at the endoperoxide group level, undergoes a rapid (k on the order of 10(8) s(-1) or higher) intramolecular rearrangement to give species, most likely carbon-centred radicals, that show some reactivity towards the methyl viologen radical cation (MV(*+)).

Regional anesthesia for carotid endarterectomy: a comparison between ropivacaine and levobupivacaine

BACKGROUND

This study compares ropivacaine and levobupivacaine when administered for cervical plexus block. The authors therefore compared the arterial pressure profile and the incidence of hypotension between drugs.

METHODS

Forty-eight patients scheduled for carotid artery surgery (American Society of Anesthesiologists [ASA] 2-3) were randomly assigned to receive levobupivacaine or ropivacaine (24 patients each). Neurological status, arterial pressure profile and control of postoperative pain were the main observed parameters. All patients had severe carotid stenosis (>80%) and/or had suffered transient ischemic attacks (TIAs) or preoperative strokes. The same team performed anesthesia and surgery for carotid endarterectomy; the cervical block was performed according to Moore's technique.Arterial pressure, heart rate and S(a)O(2p) were monitored continuously with particular regard to T0 (baseline), T1 (immediately before carotid clamping), T2 (immediately before declamping) and T3 (at the end of the procedure). Hypotension was defined as the fall of arterial systolic pressure 30% below baseline or less than 100 mmHg.

RESULTS

Arterial pressure fell significantly in both groups at T1 with respect to T0 (P<0.0001). Levobupivacaine patients showed higher mean arterial pressure on T0 (112+/-12 mmHg versus 103+/-7 mmHg; P<0.05), thus suggesting a more pronounced vasodilator effect, as confirmed by the larger drop of arterial diastolic pressure (P=0.007). An absolute 6% difference of hypotension-related drug was recorded with levobupivacaine (19%) as compared with ropivacaine (13%) (P=0.28).

CONCLUSIONS

Levobupivacaine has a greater vasodilatory effect than ropivacaine. Its higher incidence of hypotension, although not statistically significant, suggests ropivacaine as the drug of choice for cervical plexus block.

Investigations of 5S rDNA of Vitis vinifera L.: sequence analysis and physical mapping

Here we report the first results of a study of 5S rDNA of Vitis vinifera . 5S rDNA sequences from seven genotypes were amplified by PCR, cloned, and sequenced. Three types of repeats were found. Two variants, denominated long repeat and short repeat, appeared to be the main components of the 5S rDNA of this species, since they were found in all genotypes analyzed. They differed markedly from each other in both the length and the nucleotide composition of the spacers. The third variant, classified as DEL short repeat, differs from the short repeat owing to a large deletion in the spacer region. It appears to be the most recent repeat type, since it was identified in only one genotype. The organization of the 5S rDNA repeat unit variants was investigated by amplifying the genomic DNA with primers designed on the sequence of the long and short spacers. The PCR-amplified fragments showed that the long repeat is associated with the other two repeats, indicating that in V. vinifera different repeat units coexist within the same tandem array. FISH analysis demonstrated that 5S rRNA genes are localized at a single locus. The variability of 5S rDNA repeats is discussed in relation to the putative allopolyploid origin of V. vinifera.

In planta production of two peptides of the Classical Swine Fever Virus (CSFV) E2 glycoprotein fused to the coat protein of potato virus X

BACKGROUND

Classical Swine Fever (CSFV) is one of the most important viral infectious diseases affecting wild boars and domestic pigs. The etiological agent of the disease is the CSF virus, a single stranded RNA virus belonging to the family Flaviviridae. All preventive measures in domestic pigs have been focused in interrupting the chain of infection and in avoiding the spread of CSFV within wild boars as well as interrupting transmission from wild boars to domestic pigs. The use of plant based vaccine against CSFV would be advantageous as plant organs can be distributed without the need of particular treatments such as refrigeration and therefore large areas, populated by wild animals, could be easily covered.

RESULTS

We report the in planta production of peptides of the classical swine fever (CSF) E2 glycoprotein fused to the coat protein of potato virus X. RT-PCR studies demonstrated that the peptide encoding sequences are correctly retained in the PVX construct after three sequential passage in Nicotiana benthamiana plants. Sequence analysis of RT-PCR products confirmed that the epitope coding sequences are replicated with high fidelity during PVX infection. Partially purified virions were able to induce an immune response in rabbits.

CONCLUSION

Previous reports have demonstrated that E2 synthetic peptides can efficiently induce an immunoprotective response in immunogenized animals. In this work we have showed that E2 peptides can be expressed in planta by using a modified PVX vector. These results are particularly promising for designing strategies for disease containment in areas inhabited by wild boars.

Living Donor Liver Transplantation and Management of Portal Venous Pressure

Small-for-size syndrome occurs in the presence of a reduced mass of liver that is insufficient to maintain normal liver function. It has been speculated that this dysfunction is principally associated with graft exposure to excessive portal perfusion. The aim of these cases was to evaluate the efficacy of octreotide, a splanchnic vasoconstrictor, and esmolol, a selective beta-blocker, to modify the portal perfusion in the postoperative phase after left living related liver transplantation (LRLT). Four patients who underwent left LRLT with graft-to-recipient weight ratios of 0.60 +/- 0.24 were studied with a catheter placed in a jejunal vein. We observed high basal values of hepatic venous pressure gradient (HVPG) and portal vein flow (PVF). Octreotide infusion decreased HVPG, an effect that was more pronounced when it was combined with esmolol. The administration of both drugs was also associated with an improvement in portal vein oxygen saturation. Despite variation in PVF, the plasma disappearance rate of indocyanin green did not change during the infusion of the two drugs. In conclusion, octreotide and esmolol infusion allowed a manipulation of portal vein pressure that should be measured in left LRLT using a small-for-size graft.

Opioid-related side-effects after intrathecal morphine: a prospective, randomized, double-blind dose-response study

BACKGROUND AND OBJECTIVE

The aim of this prospective, randomized, double-blind investigation was to assess the dose-effect characteristics of postoperative nausea and vomiting after intrathecal administration of small doses of morphine (from 0.015 to 0.25 mg) in opioid-naïve, non-surgical patients.

METHODS

With Ethic Committee approval and written informed consent 144 opioid-naïve patients suffering from non-cancerous chronic back-pain, and receiving intrathecal morphine as diagnostic test for their chronic pain, were randomly allocated to receive intrathecal injection of 0.015 mg (Group I, n=25), 0.03 mg (Group II, n=30), 0.06 mg (Group III, n=31) or 0.25 mg (Group IV, n=33) morphine. The control group consisted in 25 further patients not included in the dose-effect study and receiving a placebo injection of normal saline in the interspinous ligament. A blinded observer recorded the occurrence of pruritus, nausea, vomiting, urinary retention and respiratory depression (respiratory rate<6 bpm) at 2, 4 and 24 h after injection.

RESULTS

Clinically significant pain relief was observed in all patients receiving intrathecal morphine but only six patients (25%) of the control group (P=0.0005). The incidence of pruritus was lower in patients of Groups III (6%) and IV (3%) than in Groups I (12%) and II (20%) (P=0.002). The incidence of nausea and vomiting was higher at 2- and 4-h observation times, and decreased 24 h after intrathecal injection. Surprisingly, nausea was more frequent in Groups I (56%) and II (50%) than in Groups III (33%) and IV (24%) (P=0.0005). Vomiting was higher in patients receiving morphine than in control group, but without differences among the four doses. No urinary retention was observed in the control group, while 2 h after intrathecal injection urinary retention was observed in 20-40% of cases, and decreased to less than 10% 24 h after spinal injection without differences among the four doses.

CONCLUSIONS

The onset and incidence of minor opioid-related side-effects after intrathecal morphine administration do not depend on its dose, occurring with even very small doses of morphine. Accordingly, they can be considered as a patient-dependent effect of the drug, suggesting the presence of a primary dose-independent excitatory component that might be related to the theory of the bimodal activation of opioid receptors. The very low incidence major respiratory depression prevents us from drawing any conclusion about the dose-effect relationship for this side-effect, and further properly powered studies should be advocated to evaluate major respiratory depression after spinal morphine.

Alfalfa Mob 1-like genes are expressed in reproductive organs during meiosis and gametogenesis

Mps-one-binder (Mob) proteins play an important role in chromosome separation and cell plate formation in yeast. We cloned two Mob 1-like genes from alfalfa (Medicago sativa L.) and show that one gene is constitutively expressed while the other is expressed only in flower buds during sporogenesis and gametogenesis. For the analysis of gene expression during reproduction in alfalfa wild-types and apomeiotic mutants, a specific antisense riboprobe was designed for MsMob 1 transcripts and a polyclonal antibody was raised against MsMob 1 proteins. In situ mRNA localization as well as protein immunolocalization proved that MsMob1-like genes are specifically expressed in degenerating megaspores of normal ovules and in enlarged megaspore mother cells and embryo sacs of apomeiotic ovules. Gene products were also found in microspore tetrads at the beginning of pollen development as well as in tapetum cells of anthers undergoing programmed cell death to allow pollen dispersal at maturity. Overall results suggest that MsMob 1-like genes can play a key role during the reproductive pathway in plants.

SERK and APOSTART. Candidate genes for apomixis in Poa pratensis

Seed production generally requires the mating of opposite sex gametes. Apomixis, an asexual mode of reproduction, avoids both meiotic reduction and egg fertilization. The essential feature of apomixis is that an embryo is formed autonomously by parthenogenesis from an unreduced egg of an embryo sac generated through apomeiosis. If apomixis were well understood and harnessed, it could be exploited to indefinitely propagate superior hybrids or specific genotypes bearing complex gene sets. A more profound knowledge of the mechanisms that regulate reproductive events would contribute fundamentally to understanding the genetic control of the apomictic pathway. In Poa pratensis, we isolated and characterized two genes, PpSERK (SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE) and APOSTART. These full-length genes were recovered by rapid amplification of cDNA ends and their temporal and spatial expression patterns were assessed by reverse transcription-polymerase chain reaction and in situ hybridization, respectively. The expression of PpSERK and APOSTART differed in apomictic and sexual genotypes. Their putative role in cell-signaling transduction cascades and trafficking events required during sporogenesis, gametogenesis, and embryogenesis in plants is reported and discussed. We propose that, in nucellar cells of apomictic genotypes, PpSERK is the switch that channels embryo sac development and that it may also redirect signaling gene products to compartments other than their typical ones. The involvement of APOSTART in meiosis and programmed cell death is also discussed.

Isolation of candidate genes for apomixis in Poa pratensis L

The essential feature of apomixis is that an embryo is formed autonomously by parthenogenesis from an unreduced egg of an embryo sac generated through apomeiosis. The genetic constitution of the offspring is, therefore, usually identical to the maternal parent, a trait of great interest to plant breeders. If apomixis were well understood and harnessed, it could be exploited to indefinitely propagate superior hybrids or specific genotypes bearing complex gene sets. A fundamental contribution to the understanding of the genetic control of the apomictic pathway could be provided by a deep knowledge of molecular mechanisms that regulate the reproductive events. In Poa pratensis the cDNA-AFLP method of mRNA profiling allowed us to visualize a total of 2248 transcript-derived fragments and to isolate 179 sequences that differed qualitatively or quantitatively between apomictic and sexual genotypes at the time of flowering when the primary stages of apomixis occur. Three ESTs were chosen for further molecular characterization because of their cDNA-AFLP expression pattern and BLAST information retrieval. The full-lengths of the newly isolated genes were recovered by RACE and their temporal expression patterns were assessed by RT-PCR. Their putative role in cell signaling transduction cascades and trafficking events required during sporogenesis, gametogenesis and embryogenesis in plants is reported and discussed.