Role of Zr loading into In2O3 catalysts for the direct conversion of CO2/CO mixtures into light olefins

The effect of the ZrO₂ content on the performance (activity, selectivity, stability) of In₂O₃-ZrO₂ catalyst has been studied on the hydrogenation of CO₂/CO mixtures. This effect is a key feature for the viability of using In₂O₃-ZrO₂/SAPO-34 tandem catalysts for the direct conversion of CO₂ and syngas into olefins via oxygenates as intermediates. The interest of co-feeding syngas together with CO₂ resides in jointly valorizing syngas derived from biomass or wastes (via gasification) and supplying the required H₂. The experiments of methanol synthesis and direct synthesis of olefins, with In₂O₃-ZrO₂ and In₂O₃-ZrO₂/SAPO-34 catalysts, respectively, have been carried out under the appropriate conditions for the direct olefins synthesis (400 °C, 30 bar, H₂/CO_X ratio = 3) in an isothermal fixed bed reactor at low space time values (kinetic conditions) to evaluate the behavior and deactivation of the catalysts. The Zr/In ratio of 1/2 favors the conversion of CO₂ and CO_X, attaining good oxygenates selectivity, and prevents the sintering attributable to the over-reduction of the In₂O₃ (more significant for syngas feeds). The improvement is more remarkable in the direct olefins synthesis, where the thermodynamic equilibrium of methanol formation is displaced, and methanation suppressed (in a greater extent for feeds with high CO content). With the In₂O₃-ZrO₂/SAPO-34 tandem catalysts, the conversion of CO_x almost 5 folds respect oxygenates synthesis with In₂O₃-ZrO₂ catalyst, meaning the yield of the target products boosts from ∼0.5% of oxygenates to >3% of olefins (selectivity >70%) for mixtures of CO₂/CO_X of 0.5, where an optimum performance has been obtained.

'Candidatus Neoehrlichia mikurensis' in Europe

'Candidatus Neoehrlichia mikurensis' is an uncultured emerging bacterium that is provisionally included in the family Anaplasmataceae. In Europe, it is transmitted by Ixodes ricinus ticks. Rodents are the reservoirs. It is widely distributed in mammals (both wild and domestic) and birds. It causes an inflammatory disease in humans with underlying diseases, but the microorganism also affects immunocompetent individuals in which asymptomatic infection has been recognized. A high degree of suspicion and the use of molecular tools are needed for the correct diagnosis. Efforts to cultivate it and to investigate its pathogenesis should be a priority.

IgE to α-Gal in Foresters and Forest Workers From La Rioja, North of Spain

OBJECTIVE

To investigate the prevalence of and factors associated with the presence of α-gal-specific IgE in a risk group of foresters and forest workers from La Rioja, Spain and in a control group.

METHODS

The study population comprised 169 workers and 100 individuals who did not recall having had tick bites. A questionnaire including demographic data and number of tick bites per year was completed by a physician. α-Gal sIgE was assessed using ImmunoCAP with serum samples that had been taken in 2010. In 2015, second serum specimens were taken from all but 1 of the workers, who had positive specific IgE to α-gal in 2010. These new samples were tested for IgE to the α-gal epitope and to mammalian meat.

RESULTS

The prevalence of positive sIgE to α-gal was 15% in the risk population and 4% in the control population. α-Gal sIgE positivity was associated with the number of tick bites per year and with seniority. Thirteen out of 21 patients sensitized to α-gal in 2010 showed positive specific IgE to α-gal in serum samples from 2015. Eleven had specific IgE to mammalian meat, but none reported symptoms of meat allergy.

CONCLUSIONS

The prevalence of α-gal sIgE antibodies in this risk population was higher than in the control group and was associated with the number of tick bites per year and with seniority. None of the workers sensitized to mammalian meat developed meat allergy, possibly owing to the low levels of sIgE to α-gal.

Isolation of Rickettsia amblyommatis in HUVEC line

Rickettsia amblyommatis, formerly named Rickettsia amblyommii and ‘Candidatus Rickettsia amblyommii’ is an intracellular bacterium belonging to the spotted fever group Rickettsia. It is highly prevalent in Amblyomma americanum and in other Amblyomma spp. throughout the Western Hemisphere. R. amblyommatis has been cultivated in chicken fibroblast, primary embryonated chicken eggs, Vero cells and arthropod-derived cells. Because of the affinity of rickettsiae to invade vascular endothelial cells, we tried to isolate R. amblyommatis from a nymph of Amblyomma cajennense s.l. collected in Saltillo (Coahulia, Mexico) using human umbilical vein endothelial cells (HUVEC). One tick half was analysed by ompA PCR and was found to be positive for R. amblyommatis. The other half was selected for in vitro culture of Rickettsia spp. It was triturated in 1 mL of endothelial cell growth medium with 1% antibiotic–antimycotic solution, and the homogenate was inoculated into a HUVEC line. Culture was maintained at 33°C in endothelial cell growth medium plus 2 mM l-glutamine and 2% fetal calf serum, with 5% CO_2. The medium was changed weekly. Culture was checked by Gimenez stain for Rickettsia-like intracellular organisms. After 48 days of incubation, Rickettsia-like organisms were observed in HUVEC. PCR assays and sequencing of ompA gene in the culture suspension showed 100% identity with R. amblyommatis. This isolate was successfully established in HUVEC, and it has been deposited in the collection of the Center of Rickettsioses and Arthropod-Borne Diseases, Infectious Diseases Department, Hospital San Pedro–Center of Biomedical Research from La Rioja, Logroño, Spain. The HUVEC line is a useful tool for the isolation of R. amblyommatis.

Rickettsia conorii is a potent complement activator in vivo and combined inhibition of complement and CD14 is required for attenuation of the cytokine response ex vivo

Mediterranean spotted fever caused by Rickettsia conorii is a potentially lethal disease characterized by vascular inflammation affecting multiple organs. Studies of R. conorii so far have focused on activation of inflammatory cells and their release of inflammatory cytokines, but complement activation has not been investigated in R. conorii-infected patients. Here, we performed a comprehensive analysis of complement activation markers and the soluble cross-talking co-receptor CD14 (sCD14) in plasma from R. conorii-infected patients. The clinical data were supplemented with ex vivo experiments where the cytokine response was characterized in human whole blood stimulated with R. conorii. Complement activation markers at the level of C3 (C3bc, C3bBbP) and terminal pathway activation (sC5b-9), as well as sCD14, were markedly elevated (p <0.01 for all), and closely correlated (p <0.05 for all), in patients at admission compared with healthy matched controls. All tested markers were significantly reduced to baseline values at time of follow up. Rickettsia conorii incubated in human whole blood was shown to trigger complement activation accompanied by release of the inflammatory cytokines interleukin-1β (IL-1β), IL-6, IL-8 and tumour necrosis factor. Whereas inhibition of either C3 or CD14 had only a minor effect on released cytokines, combined inhibition of C3 and CD14 resulted in significant reduction, virtually to baseline levels, of the four cytokines (p <0.05 for all). Our data show that complement is markedly activated upon R. conorii infection and complement activation is, together with CD14, responsible for a major part of the cytokine response induced by R. conorii in human whole blood.

Detection of tick-borne Anaplasma bovis, Anaplasma phagocytophilum and Anaplasma centrale in Spain

The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes species of medical and veterinary importance. The presence of Anaplasma spp. in ticks from birds, as well as in Haemaphysalis punctata (Ixodida: Ixodidae) specimens collected from cattle and vegetation in northern Spain was investigated. A total of 336 ticks from birds [174 Ixodes frontalis (Ixodida: Ixodidae), 108 H. punctata, 34 Hyalomma marginatum (Ixodida: Ixodidae), 17 Ixodes ricinus (Ixodida: Ixodidae) and three Ixodes spp.], and 181 H. punctata specimens collected from cattle (n = 71) and vegetation (n = 110) were analysed. Anaplasma bovis was detected in five H. punctata, including two from birds (1.9%) and three from vegetation (2.7%). Four I. frontalis (2.3%) (one co-infected with 'Candidatus Midichloria mitochondrii') and one I. ricinus (5.9%) removed from birds, as well as four H. punctata (5.6%) collected from cattle showed Anaplasma phagocytophilum infection. In addition, Anaplasma centrale was found in two H. punctata, one from a cow (1.4%) and the other from vegetation (0.9%). This study represents the first evidence of the presence of A. bovis in European ticks, and reports the first detection of A. bovis and A. centrale in H. punctata, and the first finding of A. phagocytophilum and 'Ca. Midichloria mitochondrii' in I. frontalis.

Evaluation of IgG antibody response against Rickettsia conorii and Rickettsia slovaca in patients with DEBONEL/TIBOLA

The aim of the study was to determine the IgG antibody response to spotted fever group Rickettsia (SFGR) R. conorii and R. slovaca, and its specificity and sensitivity in patients with DEBONEL/TIBOLA. A prospective study of 31 patients with DEBONEL was carried out from January 2001 to May 2004. The SFGR serology testing (IgG IFA) for the diagnosis of DEBONEL/TIBOLA showed 61% sensitivity and 100% specificity. The R. slovaca antigen allowed the diagnoses in 18 of the 31 patients (58%), and 17 patients (55%) were diagnosed with this disease using R. conorii antigen. Therefore, using R. slovaca as antigen did not improve the sensitivity of the assay.

Human Anaplasmosis: The First Spanish Case Confirmed by PCR

We report a case of human anaplasmosis (HA) fulfilling the confirmation criteria: epidemiologic data and clinical picture compatible with HA; presence of a morulae within polymorphonuclear leukocyte; and positive PCR assay for Anaplasma phagocytophilum: This case report shows the presence of HA in Spain.

Rickettsia slovaca Infection: DEBONEL/TIBOLA

This study describes the epidemiological, clinical, and microbiological characteristics of a new tick-borne disease in Spain-Dermacentor-borne necrosis erythema lymphadenopathy (DEBONEL). The clinical presentations include an eschar at the site of the tick bite, surrounded by an erythema and painful regional lymphadenopathy. The disease appears during the colder months and its vector is Dermacentor marginatus (D. marginatus). From January 1990 to December 2004, 54 patients presented at Hospital of La Rioja with these clinical and epidemiological data. The ratio of females to males was 32/22. The average age was 37 years. In all cases tick bites were located on the upper body (90% on the scalp). The median incubation period was 4.7 days. Signs and symptoms were mild in all cases. Only a small number of patients presented mild and nonspecific abnormalities in a complete blood cell count and mild elevation of erythrocyte sedimentation rates and C-protein reactive and liver enzyme levels. Serological evidence of acute rickettsiosis was observed in 19 patients (61%). In 29% sera tested by polymerase chain reactions (PCRs) were positive. The sequence obtained from a PCR product revealed 98% identity with Rickettsia sp. strains RpA4, DnS14, and DnS28. All ticks removed from patients were PCR-positive. Sequencing showed 8 of them identified as R. slovaca and 2 as Rickettsia sp. strains RpA4, DnS14, and DnS28.

Prevalence of Spotted Fever Group Rickettsia Species Detected in Ticks in La Rioja, Spain

Our objective was to learn the prevalence of spotted fever group (SFG) Rickettsia detected in ticks in La Rioja, in the north of Spain. From 2001 to 2005, 496 ticks representing 7 tick species were analysed at the Hospital de La Rioja. Ticks were removed from humans with or without rickettsial syndrome (n = 59) or collected from mammals (n = 371) or from vegetation by dragging (n = 66). The presence of SFG Rickettsia in these ticks was investigated by semi-nested PCR (ompA gene) and sequencing. A phylogenetic tree using Clustal method (neighbor-joining) was constructed with these data. Only 3 of 170 Hyalomma marginatum ticks carried SFG Rickettsia. Sequencing analysis demonstrated the presence of Rickettsia aeschlimannii (1.8%). Furthermore, Rickettsia massiliae and BAR29 were found in 3 of 120 Rhipicephalus sanguineus specimens (2.5%). In contrast, 81 of 83 tested Dermacentor marginatus ticks were PCR-positive (97%). Rickettsia slovaca (40.6%) and Rickettsia sp. strains RpA4, DnS14, DnS28 and JL-02 (59.3%) were found within this tick species. No SFG Rickettsia was detected using ompA primers when Ixodes ricinus, Rhipicephalus bursa, Rhipicephalus turanicus, Rhipicephalus eversti eversti, Hyalomma detritum scupense and Rhipicephalus sp. were analyzed. We detected 17.5% of ticks associated with different SFG Rickettsia: R. aeschlimannii, R. massiliae, BAR29, R. slovaca and Rickettsia sp. strains RpA4, DnS14, DnS28 and JL-02. Their presence has to be taken into account since most of them have been recognized as human pathogens.

Effect of Antibiotic Treatment in Patients with DEBONEL/TIBOLA

DEBONEL/TIBOLA is a tick-borne acute/sub-acute infection transmitted in our environment by Dermacentor marginatus and mainly caused by Rickettsia slovaca. The aim of our study was to know the effect of starting early treatment in the course of the DEBONEL/TIBOLA.

Detection of a Non-Pathogenic Variant of Anaplasma phagocytophilum in Ixodes ricinus from La Rioja, Spain

Our aim was to identify variants of Anaplasma phagocytophilum 16S rRNA gene sequences among products amplified from Ixodes ricinus collected in La Rioja, Spain. A. phagocytophilum AP-variant 1, reported as non-pathogenic, was detected in 12 samples (two adults and ten nymphs). This finding could justify the low incidence of human anaplasmosis in our area, despite the high prevalence of A. phagocytophilum in ticks.

Dermacentor-borne necrosis erythema and lymphadenopathy: clinical and epidemiological features of a new tick-borne disease

This paper describes the epidemiological and clinical features of a tick-borne disease differing somewhat from other tick-borne diseases found previously in Spain. All patients were bitten by Dermacentor marginatus or a large tick. The clinical features include a crustaceous or necrotic lesion at the site of the tick's attachment, surrounded by an erythema (erythema migrans-like) and painful regional lymphadenopathies. The probable aetiological agent is Rickettsia slovaca. Similar cases have been reported in other European countries.

Clonal diversity among erythromycin-resistant beta-haemolytic Streptococcus isolates in La Rioja, Spain

OBJECTIVE

To analyse clonal diversity in 72 erythromycin-resistant beta-haemolytic streptococci.

METHODS

Clonal relationships were studied for streptococci of groups A (GAS, n = 30), B (GBS, n = 34), C (GCS, n = 4) and G (GGS, n = 4) by means of PFGE. Streptococcal isolates were obtained from a 450-bed hospital in Spain during the following periods: GAS (1996-2001), GBS (1999-2001), GCS and GGS (1997-2000).

RESULTS

Twenty-two of the 30 GAS isolates showed the M resistance phenotype and harboured the mef(A) gene. Five unrelated PFGE patterns were identified among these 22 GAS isolates. Sixteen of them, obtained during four different years of the study, showed one of the two predominant PFGE patterns. The remaining eight GAS isolates showed the MLSB resistance phenotype, and four unrelated PFGE patterns were detected. All but one erythromycin-resistant GBS showed the MLSB resistance phenotype, and an erm gene was identified in all cases [erm(B) or erm(A)]. Twenty-two unrelated PFGE patterns were demonstrated among 25 GBS with the MLSB resistance phenotype; the remaining eight MLSB GBS isolates could not be typed by PFGE. The eight erythromycin-resistant GGS and GCS isolates of this study presented seven unrelated PFGE patterns. GGS and GCS strains showed an MLSB resistance phenotype and had the erm(A) gene.

CONCLUSIONS

High clonal diversity was detected in this series of erythromycin-resistant GBS, whereas lower diversity was seen in the GAS isolates.

Immunocytochemical characterization of adenohypophyseal cells in the greater weever fish (Trachinus draco)

The adenohypophysis of the greater weever fish (Trachinus draco) was studied using histochemical and immunocytochemical methods. The adenohypophysis comprised the rostral pars distalis (RPD), the proximal pars distalis (PPD), and the pars intermedia (PI). Neurohypophysis showed a patent hypophyseal stalk which was divided into several branches intermingled with the adenohypophysis. Salmon prolactin (PRL)-immunoreactive (ir) cells, arranged in follicles, resided in the RPD and the most rostral part of the ventral PPD. Human adrenocorticotropin (ACTH)-ir cells were located in the RPD between PRL-ir cells and the neurohypophyseal processes. Salmon and seabream somatotropin (GH)-ir cells were located in both the dorsal and the ventral PPD. Some GH-ir cells were seen in surrounding and in contact with neurohypophyseal branches, whereas other isolated or clustered GH-ir cells were embedded in adenohypophyseal cells of the PPD. In addition, isolated or clustered GH-ir cells were also detected in the tissue of the PPD covering the most rostral part of PI. Only one class of salmon and carp gonadotropin (GTH)-ir cells was detected. Isolated or clustered GTH-ir cells resided in both the dorsal and the ventral PPD and were seen surrounding the PI and in the tissue of the PPD covering the most rostral part of PI. In addition, a few scattered GTH-ir cells were observed in the ventral RPD. Scattered groups of thyrotropin (TSH)-ir cells were present in the anteroventral PPD. Salmon and seabream somatolactin (SL)-ir and bovine melanotropin (MSH)-ir cells were intermingled surrounding the neurohypophyseal tissue. SL-ir cells were negative to periodic acid-Schiff technique. MSH-ir cells showed a very weak immunoreactivity to anti-human ACTH((1-24)) serum. In addition to the PI location, few isolated or clustered SL- and MSH-ir cells were observed in the dorsal PPD.

Antifungal activity of Paraguayan plants used in traditional medicine

The antifungal activity of aqueous, dichloromethane and methanol extracts from 14 Paraguayan plants used in traditional medicine for the treatment of skin diseases was assayed in vitro by the agar disk diffusion method against 11 fungal strains comprising several filamentous fungi and yeasts. Among them, the dichloromethane extracts of Acanthospermum australe, Calycophyllum multiflorum, Geophila repens and Tabebuia avellanedae, as well as the aqueous and methanol extracts of the latter, showed the highest activity.

Macrolide resistance genes in Enterococcus spp

Seventy-eight isolates of different Enterococcus species (E. faecalis, n = 27; E. faecium, n = 23; E. durans, n = 8; E. avium, n = 6; E. hirae, n = 9; E. gallinarum, n = 3; and E. casseliflavus, n = 2) with a variety of erythromycin resistance phenotypes were examined for the presence of macrolide resistance genes (ermA, ermB, ermC, ermTR, mefA/E, and msrA). Positive PCR amplifications of ermB were obtained for 39 of 40 highly erythromycin-resistant Enterococcus isolates (MICs, >128 microg/ml) of different species; the remaining highly resistant E. faecium isolate was positive for PCR amplification of ermA but was negative for PCR amplification of the ermB and ermC genes. For all enterococcal strains for which erythromycin MICs were < or =32 microg/ml PCRs were negative for erm methylase genes. For all E. faecium isolates PCR amplified products of the expected size of 400 bp were obtained when msrA primers were used, with the results being independent of the erythromycin resistance phenotype. All the other enterococcal species gave negative results by msrA PCRs. Sequencing of the msrA PCR products from either erythromycin-susceptible, low-level-resistant, or highly resistant E. faecium strains showed that the amplicons did not correspond to the msrA gene described for Staphylococcus epidermidis but corresponded to a new putative efflux determinant, which showed 62% identity with the msrA gene at the DNA level and 72% similarity at the amino acid level. This new gene was named msrC.

In vitro activities of ketolide HMR3647, macrolides, and other antibiotics against Lactobacillus, Leuconostoc, and Pediococcus isolates

Testing of susceptibility to 13 antibiotics was performed with 90 isolates of Lactobacillus, Leuconostoc, and Pediococcus. MICs at which 90% of the isolates tested were inhibited by HMR3647, erythromycin, and ciprofloxacin were 0.015, 0.125 and 32 microg/ml, respectively. The penicillin MIC was > or = 16 microg/ml against 26.2% of the studied Lactobacillus sp. isolates and 50% of Lactobacillus plantarum. HMR3647 showed excellent activity against these genera.

Macrolide resistance phenotypes and mechanisms of resistance in Streptococcus pyogenes in La Rioja, Spain

One hundred and thirty seven consecutive clinical Streptococcus pyogenes isolates were evaluated for macrolide-lincosamide-streptogramin resistance (MLS). Forty of these isolates were resistant to erythromycin (29.2%), 36 of them showed the new M resistance phenotype (erythromycin resistant and clindamycin susceptible) and four isolates had the MLS(B) resistance phenotype (erythromycin and clindamycin resistant). In all 36 isolates with the M resistance phenotype, the mef gene was identified by polymerase chain reaction (PCR). In two of the four S. pyogenes isolates with the MLS(B) phenotype, both ermB and ermTR genes were found; negative results were obtained with the other two isolates which might possess a new mechanism of high level resistance against erythromycin not previously described. In summary, a high rate of erythromycin resistance was found in S. pyogenes isolates and the active efflux pump mediated by the mef gene was the mechanism most frequently involved.

In vitro activity of the new ketolide HMR3647 in comparison with those of macrolides and pristinamycins against Enterococcus spp

Ninety-four erythromycin-susceptible and 107 erythromycin-resistant enterococcal strains (MIC of >/=512 microgram/ml) were inhibited by the ketolide HMR3647 at MICs of </=0.007 to 0.06 and 0.03 to 8 microgram/ml, respectively. Eighteen vanA-positive isolates and 29 high-level-penicillin-resistant isolates, all of them erythromycin resistant, were inhibited by HMR3647 at an MIC range of 0.015 to 4 microgram/ml. The new ketolide has excellent activity against Enterococcus species.

Compared contralateral application of topical nitroglycerin on purpura fulminans

In cases of purpura fulminans (PF), various treatments have been used to prevent the cutaneous involvement and extensive skin necrosis that can be both disfuguring and debilitating. In this article, we present a case where improvement in the progression of purpuric areas was accomplished by topical administration of nitroglycerin (TNG), as evidenced by comparison with symmetrical contralateral areas not so treated.