Introduction Lumbar dermoid cysts and other occult dysraphisms are sometimes difficult to diagnose. These anomalies are occasionally detected after a nervous central system infection. Case Report ...Previously healthy 10 month-old child, admitted after a first febrile generalized seizure with nuchal rigidity and bulging fontanel. A very small blind lumbar dimple above the 5th lumbar vertebra was noticed. Cerebrospinal fluid (CSF) was consistent with bacterial meningitis and penicillin susceptible Klebliella spp was identified. Brain CT-scan was normal and CSF was sterile after 4 days of ceftriaxone. She completed 21 days of therapy, with clinical improvement. One week after, she was readmitted with fever, lethargy and opisthotonus. Klebsiella oxytoca meningitis was diagnosed and treated for 3 weeks with ceftriaxone and gentamicin, according to antibiotic susceptibility test. Brain and spine magnetic resonance imaging showed a L4-L5 lumbo-sacral intrarachidian dermoid cyst with a fistulous path to skin surface. Surgical closure of fistula was performed on day 23 of therapy. This child is currently under antibiotic chemoprophylaxis with amoxicillin/clavulanate, awaiting removal of dermoid cyst under optimal sterile conditions. Neurological exam and motor development have been normal. Conclusions A strong clinical suspicion is necessary in order to diagnose occult dysraphism and spinal midline cysts, before complications occur. A careful examination of the midline is warranted in all infants, paying special attention to skin pits outside coccigeal area, even if apparently blind. This diagnosis should also be considered in cases of recurrent or unusual bacterial associated central nervous system infections.
Patients bitten by
Loxosceles spiders generally manifest marked local inflammatory reaction and dermonecrosis. This report evaluated edema formation, leukocyte infiltration and release of ...inflammatory mediators at the injection site of
Loxosceles gaucho venom. BALB/c mice were i.d. injected with venom and thereafter paws were disrupted and homogenized to obtain differential counts of migrated cells, as well to assay the levels of cytokines, chemokines and lipid mediators. Increased footpad thickness was detected as soon as 30
min after venom injection, and 24
h later was similar to that of the control group.
Loxosceles venom mildly augmented the recruitment of leukocytes to the footpad in comparison with PBS-injected mice. Moreover, it stimulated the release of IL-6, MCP-1 and KC at 2 and 24
h after venom injection. In addition, higher levels of PGE
2 were detected 30
min after venom injection in comparison with control group. However, the venom failed to increase levels of IL-1β, TNF-α, TXB
2 and LTB
4. Our results demonstrate that
L. gaucho venom evokes an early complex inflammatory reaction, stimulating the secretion of pro-inflammatory cytokines and lipid mediators (PGE
2), and recruiting leukocytes to the footpad which contribute to the local reaction induced by
L. gaucho venom.
Molecular characterization of
Giardia duodenalis
in African countries is relatively scarce. The global understanding of
Giardia
epidemiology is reinforced when more data are available from highly ...endemic countries. In the present study, 50 fecal samples collected from children from Guinea-Bissau were screened for
Giardia
infection. Amplification of the
Giardia ssu
-
rRNA
fragment was achieved for 28 samples (28/50, 56.0 %) of which 23 (23/50, 46.0 %) positive samples for
Giardia
were detected through microscopy. Eighteen samples previous amplified for the
ssu
-
rRNA
locus were amplified for the
bg
gene fragment. Sequence analysis was performed in 26 and 17 samples for the
ssu
-
rRNA
and
bg
gene fragment, respectively. Our results revealed a predominance of assemblage B (22/26, 84.6 %), sequences with high genetic polymorphism among isolates belonging to this assemblage, making impossible the subassemblage determination. Assemblage A was identified in three isolates (3/26, 11.5 %), and our results strongly suggest that two isolates belong to subassemblage A2. This study provides information about
G. duodenalis
genotypes in a rural area of Guinea-Bissau and may contribute for a better understanding of giardiasis epidemiology in this country.
Venoms of spiders and snakes contain toxins extremely active and, thus, provide a natural source for the development of new biotechnological tools. Among the diversity of toxins present in the venom ...of spiders from genus Loxosceles, the phospholipases D (PLDs) show high hydrolytic activity upon lysophosphatidylcholine (LPC) and sphingomyelin (SM), generating bioactive phospholipids such as cyclic phosphatidic acid (cPA). Since this mediator has been shown to play a major role in complex signaling pathways, including inhibition of tumor cells, the PLDs may hold the key to learn how toxins could be used for therapeutic purposes. However, the strong platelet aggregation of PLDs and their lack of selectivity impose a major limitation. On the other hand, disintegrins present in the venoms of Viperidae snakes are a potent inhibitor of platelet aggregation and possess high affinity and specificity to molecules called integrins that are highly expressed in some tumor cells, such as murine melanoma B16F10. Therefore, disintegrins might be suitable molecules to carry the PLDs to the malignant cells, so both toxins may work synergistically to eliminate these cells. Thus, in this work, a recombinant PLD from Loxosceles gaucho spider was recombinantly fused to a disintegrin from Echis carinatus snake to form a hybrid toxin called Rechistatin. This recombinant toxin was successfully expressed in bacteria, showed binding activity in B16F10 murine melanoma cells and exerted a synergistic cytotoxicity effect on these cells. Therefore, the approach presented in this work may represent a new strategy to explore new potential applications for spider PLDs.
•Hybrid toxin Rechistatin suppressed platelet aggregation at higher doses.•Rechistatin was able to bind to murine B16F10 melanoma cells.•Rechistatin showed cytotoxicity on B16F10 melanoma cells.
Summary
Background
The fear of side‐effects has led to strict regulations preventing a more widespread use of specific immunotherapy (SIT) in some countries, in spite of the low risk of systemic ...reactions (SRs) reported in well‐controlled studies. The goal of the study was to carry out a prospective and multi‐centric trial to evaluate the safety, risk factors and compliance degree of commercially available SIT.
Materials and methods
The study was carried out in 14 allergy departments from Spain. Four‐hundred and eighty‐eight patients with rhinitis and/or asthma were submitted to treatment with biologically standardized allergen extracts commercially available. They were administered following the European Academy of Allergy and Clinical Immunology guidelines.
Results
Four hundred and twenty‐three patients (86.7%) completed the treatment and remained under control at the end of the trial. Out of 17 526 administered doses, 17 368 doses (99.1%) were not associated with a reaction. Eighteen patients (3.7%) experienced 53 (0.3% of the doses) SRs. All immediate SRs were mild or moderate and responded well to ordinary treatment measures. There were no fatal reactions, anaphylactic shock or life‐threatening reactions. A higher ratio of SRs was found among asthmatic and dust mite allergic patients, although multi‐variable logistic analysis did not demonstrate any risk factor associated with SRs. There was also a subgroup of patients at risk for recurrent reactions, and therefore 40% of SRs had been avoided if the maximal number of SRs had been previously limited to only three SRs.
Conclusions
This multi‐centric study showed that SIT was a safe treatment with a very good compliance. Future guidelines of SIT should limit the maximal number of SRs.
Many radiation detectors make use of an electric field to drift the electrons that result from the absorption of the incoming radiation. Previous simulation studies have demonstrated that, in gas ...detectors, the fact that charged particles exchange energy with the field leads to a degradation of the system's spectroscopic capabilities. New geometries based on opposite electric fields may reduce this effect, as somehow, a compensation of the energy that is gained/lost from/to the field is achieved. In this communication, the performance of several xenon-based radiation detectors with these novel geometries was assessed using the Monte Carlo code PENELOPE. At energies of 100 and 200 keV, and considering 1, 2, 4 and 8 regions with opposite electric fields, the simulation results indicate that the degradation associated with the drift electric field can be reduced and that this achievement is more noticeable for higher photon energies. In what concerns the absorption of 200 keV photons, when considering a detector with 8 regions, rather than one with a standard geometry, it has been observed a decrease of 81% in the FWHM of the gaussian curve describing the peak that corresponds to full energy absorption events.
The 235U neutron-induced cross section is widely used as reference cross section for measuring other fission cross sections, but in the resonance region it is not considered as an IAEA standard ...because of the scarce experimental data covering the full region. In this work, we deal with a new analysis of the experimental data obtained with a detection setup based on parallel plate ionization chambers (PPACs) at the CERN n_TOF facility in the range from 1 eV to 10 keV. The relative cross section has been normalised to the IAEA value in the region between 7.8 and 11 eV, which is claimed as well-known. Comparison with the ENDF/B-VII evaluation and the IAEA reference file from 100 eV to 10 keV are provided.
Intestinal parasites, both helminths and protozoa, are commonly found in domestic animals, and the possible transmission of enteric parasites from dogs and cats to humans may constitute a global ...potential health risk worldwide. In the present study, we analysed 148 stool samples from dogs (
n
=
126) and cats (
n
=
22) collected from animal shelters and veterinary clinics, in the district of Évora, Portugal. Microscopic examination confirmed that
Giardia was the most frequent parasite in the studied population (34/148; 23%). Other parasites such as
Ancylostoma sp.,
Isospora spp.,
Toxocara,
Trichuris spp.,
Toxascaris and
Toxoplasma were also found. Furthermore, molecular characterization of
Giardia duodenalis analysis targeting the small subunit ribosomal RNA (
ssu-rRNA) was performed revealing the presence of host-specific (C and D) and zoonotic assemblages (A and B). This work points out to the importance of protozoan parasites in companion animals, and reanalyses the need for parasite prophylaxis.
The photopeak shift in High Pressure Xe (HPXe) gamma ray detectors due to the energy acquired/lost by the photoelectric and Compton electrons, from the electric field applied in the drift region, is ...calculated using the PENELOPE code for gamma rays from several radioactive sources. The implications of this effect in HPXe detectors are discussed, namely for TPCs for double beta decay of 136 Xe studies.
This work aimed to investigate mechanisms underlying the inflammatory response caused by Potamotrygon motoro stingray venom (PmV) in mouse paws. Pre-treatment of animals with a mast cell ...degranulation inhibitor (cromolyn) diminished edema (62% of inhibition) and leukocyte influx into the site of PmV injection. Promethazine (histamine type 1 receptor antagonist) or thioperamide (histamine type 3 and 4 receptor antagonist) also decreased edema (up to 30%) and leukocyte numbers, mainly neutrophils (40–50 %). Cimetidine (histamine type 2 receptor antagonist) had no effect on PmV-induced inflammation. In the RBL-2H3 lineage of mast cells, PmV caused proper cell activation, in a dose-dependent manner, with release of PGD2 and PGE2. In addition, the role of COXs products on PmV inflammatory response was evaluated. Indomethacin (COX-1/COX-2 inhibitor) or etoricoxib (COX-2 inhibitor) partially diminished edema (around 20%) in PmV-injected mice. Indomethacin, but not etoricoxib, modulated neutrophil influx into the site of venom injection. In conclusion, mast cell degranulation and histamine, besides COXs products, play an important role in PmV-induced reaction. Since PmV mechanism of action remains unknown, hindering accurate treatment, clinical studies can be performed to validate the prescription of antihistaminic drugs, besides NSAIDs, to patients injured by freshwater stingrays.
•Mast cells degranulation and histamine contribute to edema and cell influx induced by P. motoro venom.•H1 and H3/H4 histamine receptors participate in P. motoro venom inflammatory reaction.•P. motoro venom directly causes activation of mast cells in vitro.•Cyclooxygenases products also contribute to the inflammatory response induced by P. motoro venom.
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