The effect of excluding ungulates on the abundance of ixodid ticks on wild rabbit (Oryctolagus cuniculus)

Tick abundance depends heavily on host density, so reducing access to the host should reduce tick populations in a determined area. In this study we compared the Parasitic Index (PI = average number of ticks per rabbit) of two wild rabbit populations separated 16 years ago by a fence keeping ungulates from moving freely. Two areas were selected (closed and open) wherein 50 wild rabbits per area were sampled for ticks. The PI in the open area (PI = 989.62) was significantly higher than in the closed area (PI = 515.40). Hyalomma lusitanicum Koch was globally the most abundant species, followed by Rhipicephalus pusillus Gil Collado, Rhipicephalus bursa Canestrini and Fanzago, Haemaphysalis hispanica Gil Collado, Rhipicephalus sanguineus s.l. Latreille and Ixodes ventalloi Gil Collado. Differences between areas varied depending on the species. The number of H. hispanica, R. bursa and R. pusillus were significantly more abundant on rabbits in the closed area, whereas H. lusitanicum predominated in the open area. Ungulates in the open area may have played an important role as the main or alternative host for ticks and/or drawing some tick species away from rabbits. In the closed area other reasons such as inter-specific competition could have influenced the tick abundance. These results show a clear reduction in tick abundance for at least 16 years as well as influenced species distribution.

In vitro feeding of Hyalomma lusitanicum ticks on artificial membranes

In vitro feeding of ticks (Acari: Ixodidae) is an important means to study the biology of ticks and their vectorial capacity. Here, we have adapted the tick Hyalomma lusitanicum Koch to previously published silicone-based membranes for in vitro feeding. For comparison purposes data on pre-oviposition, oviposition and hatching from females engorged on animals were used. A total of 68 engorged females out of 169 were obtained; feeding duration and feeding behaviour were similar to that of ticks on live host animals, although the final weight achieved for membrane-fed ticks was lower than that of their animal-fed counterparts. Comparison of the time taken for egg production and hatching showed that pre-oviposition was faster for membrane-fed ticks (16 days) than for animal-fed ticks (36 days), whereas the duration of oviposition-hatching was the same for the two feeding methods (34 days). We also observed that seasonality has an influence on tick feeding success: the conditions in Spring/Summer accelerated the tick life cycle. It is concluded that relatively large numbers of homogeneous laboratory-raised Hyalomma ticks can be produced without feeding them on experimental animals.

Outcome of Patients with Venous Thromboembolism and Factor V Leiden or Prothrombin 20210 Carrier Mutations During the Course of Anticoagulation

BACKGROUND

Individuals with factor V Leiden or prothrombin G20210A mutations are at a higher risk to develop venous thromboembolism. However, the influence of these polymorphisms on patient outcome during anticoagulant therapy has not been consistently explored.

METHODS

We used the Registro Informatizado de Enfermedad TromboEmbólica database to compare rates of venous thromboembolism recurrence and bleeding events occurring during the anticoagulation course in factor V Leiden carriers, prothrombin mutation carriers, and noncarriers.

RESULTS

Between March 2001 and December 2015, 10,139 patients underwent thrombophilia testing. Of these, 1384 were factor V Leiden carriers, 1115 were prothrombin mutation carriers, and 7640 were noncarriers. During the anticoagulation course, 160 patients developed recurrent deep vein thrombosis and 94 patients developed pulmonary embolism (16 died); 154 patients had major bleeding (10 died), and 291 patients had nonmajor bleeding. On multivariable analysis, factor V Leiden carriers had a similar rate of venous thromboembolism recurrence (adjusted hazard ratio [HR], 1.16; 95% confidence interval [CI], 0.82-1.64), half the rate of major bleeding (adjusted HR, 0.50; 95% CI, 0.25-0.99) and a nonsignificantly lower rate of nonmajor bleeding (adjusted HR, 0.66; 95% CI, 0.43-1.01) than noncarriers. Prothrombin mutation carriers and noncarriers had a comparable rate of venous thromboembolism recurrence (adjusted HR, 1.00; 95% CI, 0.68-1.48), major bleeding (adjusted HR, 0.75; 95% CI, 0.42-1.34), and nonmajor bleeding events (adjusted HR, 1.10; 95% CI, 0.77-1.57).

CONCLUSIONS

During the anticoagulation course, factor V Leiden carriers had a similar risk for venous thromboembolism recurrence and half the risk for major bleeding compared with noncarriers. This finding may contribute to decision-making regarding anticoagulation duration in selected factor V Leiden carriers with venous thromboembolism.

The Clinical Course of Venous Thromboembolism May Differ According to Cancer Site

BACKGROUND

We hypothesized that the clinical course of venous thromboembolism in patients with active cancer may differ according to the specificities of primary tumor site.

AIM AND METHODS

We used data from RIETE (international registry of patients with venous thromboembolism) to compare the clinical venous thromboembolism-related outcomes during the course of anticoagulation in patients with one of the 4 more frequent cancers (breast, prostate, colorectal, or lung cancer).

RESULTS

As of September 2014, 3947 cancer patients were recruited, of whom 938 had breast, 629 prostate, 1189 colorectal, and 1191 lung cancer. Overall, 55% had metastatic disease (42%, 36%, 53%, and 72%, respectively). During the course of anticoagulant therapy (mean duration, 139 days), the rate of thromboembolic recurrences was similar to the rate of major bleeding in patients with breast (5.6 [95% confidence interval (CI), 3.8-8.1] vs 4.1 [95% CI, 2.7-5.9] events per 100 patient-years) or colorectal cancer (10 [95% CI, 7.6-13] vs 12 [95% CI, 9.4-15] per 100 patient-years). In contrast, in patients with prostate cancer, the rate of venous thromboembolic recurrences was half the rate of major bleeding (6.9 [95% CI, 4.4-10] vs 13 [95% CI, 9.2-17] events per 100 patient-years), whereas in those with lung cancer, the rate of thromboembolic recurrences was twofold higher than the rate of major bleeding (27 [95% CI, 22-23] vs 11 [95% CI, 8.6-15] per 100 patient-years).

CONCLUSIONS

Significant differences in the clinical profile of venous thromboembolic-related outcomes were observed according to the site of cancer. These findings suggest the development of cancer-specific anticoagulant strategies as an area for further research.

Mapping natural radioactivity of soils in the eastern Canary Islands

The Canary Islands archipielago (Spain) comprises seven main volcanic islands and several islets that form a chain extending for around 500 km across the eastern Atlantic, between latitudes 27°N and 30°N, with its eastern edge only 100 km from the NW African coast. The administrative province of Las Palmas comprises the three eastern Canary Islands (Lanzarote, Fuerteventura and Gran Canaria). An extensive study of terrestrial gamma dose rates in surface soils has been carried out to cover the entire territory of the province (4093 km²). The average outdoor gamma dose rate in air at 1 m above ground is 73 nGyh^-1 at Gran Canaria, 32 nGyh^-1 at Fuerteventura, and 25 nGyh^-1 at Lanzarote. To complete the radiological characterization of this volcanic area, 350 soil samples at 0-5 cm depth were collected to cover all the geologic typologies of the islands. These samples were measured using high resolution gamma spectrometry to determine the activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K. The average values obtained were 25.2 Bq/kg, 28.9 Bq/kg, and 384.4 Bq/kg, respectively. Maps of terrestrial gamma activity, effective dose, and activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K for the region have been developed through the use of geostatistical interpolation techniques. These maps are in accord with the geology of the islands.

Stress, Coping, and Personality in Patients with Epicrania Fugax, and Their Relation to the Clinical Characteristics of Pain

Objective

The aim of the present work is to analyze certain psychological features in a group of patients diagnosed with Epicrania fugax (EF; that has been recently included in the appendix of the International Classification of Headache Disorders, third edition, beta version), as well as their association with diverse demographic and clinical characteristics of the sample.

Design

Case-control.

Method

Perceived Stress Scale (PSS), Stress Coping (COPE), Big Five Personality Traits (NEO-FFI), Depression (BDI-II), and Trait Anxiety (STAI) were evaluated in 23 patients with EF and 23 matched healthy controls. Differences between EF patients and controls were analyzed using the Mann-Whitney U test. Differences in psychological features as a function of the demographic and clinical characteristics were examined using one-way Analysis of Variance (ANOVA), Mann-Whitney U test, or Pearson's correlations.

Results

The two groups differed significantly from each other in Denial, Trait anxiety, and Depression. Low-frequency epicrania patients scored significantly higher than controls in Perceived stress, Neuroticism, Denial, Self-blame, Trait anxiety, and Depression and higher than high-frequency EF in Venting.

Conclusions

The results initially suggest the absence of substantial differences between patients suffering of EF and healthy controls. On the contrary, low-frequency EF patients show a distinctive "negative (unhealthy) psychological profile," in opposition to high-frequency EF patients. This circumstance highlights the potential need to consider low- frequency EF patients as a target for psychological intervention in combination with the most common medical procedures. Longitudinal studies are necessary to correctly elucidate the influence of these psychological variables on the course of EF.

Datos morfométricos de Trypanosoma evansi en carpinchos (Hydrochaeris hydrochaeris) de Chaco, Argentina

El objetivo del trabajo fue verificar la existencia de variaciones morfométricas de Trypanosoma evansi en Hydrochaeris hydrochaeris criados en cautiverio en Chaco, Argentina. Para ello se efectuaron mediciones de variables biométricas de 52 ejemplares de T. evansi provenientes de carpinchos. Se reconocieron dos variaciones morfométricas del parásito, delgadas y rechonchas. Las dimensiones de ambas formas se compararon con los resultados obtenidos en T. evansi de carpinchos del amazonas peruano. Los resultados revelaron diferencias significativas en todas las variables sometidas a estudio (p<0,05). Se concluye que al parasitar a H. hydrochaeris, T. evansi presenta dimensiones morfométricas diferentes a las halladas en Perú, variando inclusive en el mismo animal.

Venous thromboembolism in centenarians: Findings from the RIETE registry

BACKGROUND

The balance between the efficacy and safety of anticoagulant therapy in patients aged ≥100years receiving anticoagulant therapy for venous thromboembolism (VTE) is uncertain.

METHODS

We used data from the RIETE (Registro Informatizado Enfermedad TromboEmbólica) database to assess the rate of VTE recurrences, bleeding events, and mortality appearing during the course of anticoagulant therapy in VTE patients aged ≥100years.

RESULTS

Of 61,173 patients enrolled in RIETE as of January 2016, 47 (0.08%) were aged ≥100years. Of these, 10 (21%) were men, 21 (45%) presented with pulmonary embolism (PE), and 26 with deep vein thrombosis alone. Overall, 35 patients (74%) had severe renal insufficiency, 14 (30%) chronic heart failure, 30 (64%) anemia, 16 (34%) were taking antiplatelets, and 6 (13%) corticosteroids or non-steroidal anti-inflammatory drugs. Most patients (95%) were treated initially with low-molecular-weight heparin (LMWH) (mean daily dose, 168±42IU/kg). Then, 14 (30%) switched to vitamin K antagonists and 29 (62%) kept receiving long-term LMWH therapy (mean, 148±51IU/kg/day). During the course of anticoagulant therapy (mean duration, 139days), mortality was high (15/47; 32%). Two patients died of PE (initial PE one, recurrent PE one) and 5 (11%) had minor bleeding, but no major bleeding was reported.

CONCLUSIONS

Among patients with acute VTE aged ≥100years, the risk of VTE recurrences during the course of anticoagulation outweighed the risk of bleeding. Our data suggest the use of standard anticoagulant therapy in this patient population, even if they have severe renal insufficiency.

Seasonal dynamics of ixodid ticks on wild rabbits Oryctolagus cuniculus (Leporidae) from Central Spain

Rabbit Hemorrhagic Disease and Myxomatosis caused a decline in the rabbit population in the second half of the last century. Despite some recovery, the risk of vector-borne disease is present and thus the importance of controlling vector populations. In the current study, we describe the ixodid tick fauna in wild rabbit in a natural reserve in Ciudad Real (Central Spain) during the course of two 3-year periods (2007-2009 and 2012-2014). Of all the ticks collected on average 72.5 % were larvae, 24.4 % nymphs and 3.1 % adults, although the percentage varied monthly. Seven tick species were identified: Hyalomma lusitanicum Koch (Parasitic indicator [PI] = number of ticks per examined rabbit = 96.47), Rhipicephalus pusillus Gil Collado (PI = 47.37), Haemaphysalis hispanica Gil Collado (PI = 12.15), Ixodes ventalloi Gil Collado (PI = 0.65), R. bursa Canestrini and Fanzago (PI = 0.18), R. sanguineus Latreille (PI = 0.11), Dermacentor marginatus Sulzer (PI = 0.01). In spring and summer, most abundant were larvae of H. lusitanicum, followed by immature stages of R. pusillus and Ha. hispanica. In autumn, the main tick species were nymphs of I. ventalloi whereas in winter adults of Ha. hispanica were more numerous. Rhipicephalus pusillus was present all year long, although not always in high percentage. PI of other species (R. bursa, R. sanguineus and D. marginatus) were too low to be representative. The seasonal dynamics of ticks on wild rabbit defined in this study could be useful to design species-specific control strategies.

Control of Hyalomma lusitanicum (Acari: Ixodidade) Ticks Infesting Oryctolagus cuniculus (Lagomorpha: Leporidae) Using the Entomopathogenic Fungus Beauveria bassiana (Hyocreales: Clavicipitaceae) in Field Conditions

Entomopathogenic fungi are widely used to control arthropods not just in agricultural settings but also in Veterinary Medicine and Public Health. These products have been employed to control tick populations and tick-borne diseases. The effectiveness of these control measures not only depends on the fungi, but also on the tick species and environmental conditions. In Mesomediterranean areas, tick species are adapted to extreme climatic conditions and it is therefore especially important to develop suitable tick control strategies. The aim of this study was to evaluate the effectiveness of a new method of tick control which entails the application of a commercial strain of Beauveria bassiana (Balsamo, Vuillemin) on wild rabbit burrows under field conditions. Aqueous solutions of the product were applied using a mist blower sprayer into 1,717 burrows. Two trials were performed, one in spring and the other in summer. The parasitic index (PI) was calculated for 10 rabbits per treatment per time point on day +30, +60, and +90 posttreatment and efficiency was calculated by comparing the PI for ticks in treated and untreated rabbits. A total of 20,234 ixodid ticks were collected. Hyalomma lusitanicum Koch, 1844 was the most abundant tick feeding on rabbits. Treatment significantly reduced the PI in spring (by 78.63% and 63.28% on day +30 and +60, respectively; P < 0.05), but appeared to be less effective in summer, with a marginally significant tick reduction of 35.72% on day +30 (P = 0.05). Results suggest that the efficacy of applications inside burrows could be temperature-dependent and that such applications could be an economic alternative to rabbit tick control during at least two months using a diluted solution of B. bassiana conidia.

Structural Metastability and Quantum Confinement in Zn1-xCoxO Nanoparticles

This paper investigates the electronic structure of wurtzite (W) and rock-salt (RS) Zn1-xCoxO nanoparticles (NPs) by means of optical measurements under pressure (up to 25 GPa), X-ray absorption, and transmission electron microscopy. W-NPs were chemically synthesized at ambient conditions and RS-NPs were obtained by pressure-induced transformation of W-NPs. In contrast to the abrupt phase transition in W-Zn1-xCoxO as thin film or single crystal, occurring sharply at about 9 GPa, spectroscopic signatures of tetrahedral Co(2+) are observed in NPs from ambient pressure to about 17 GPa. Above this pressure, several changes in the absorption spectrum reveal a gradual and irreversible W-to-RS phase transition: (i) the fundamental band-to-band edge shifts to higher photon energies; (ii) the charge-transfer absorption band virtually disappears (or overlaps the fundamental edge); and (iii) the intensity of the crystal-field absorption peaks of Co(2+) around 2 eV decreases by an order of magnitude and shifts to 2.5 eV. After incomplete phase transition pressure cycles, the absorption edge of nontransformed W-NPs at ambient pressure exhibits a blue shift of 0.22 eV. This extra shift is interpreted in terms of quantum confinement effects. The observed gradual phase transition and metastability are related to the NP size distribution: the larger the NP, the lower the W-to-RS transition pressure.

Long term study of ixodid ticks feeding on red deer (Cervus elaphus) in a meso-Mediterranean climate

Red deer (Cervus elaphus L.) are very valuable in trophy-hunting but also contribute to the preservation of natural areas. They are affected by many parasites and pathogens, including hard ticks that are not only important parasites themselves but can also act as vectors and/or reservoirs of pathogens. Tick phenology is complex insofar as population dynamics depend on environmental conditions, vegetation, host availability and their own intrinsic characteristic. Ticks were collected monthly from January 2007 to December 2014 from red deer on a natural reserve located in a meso-Mediterranean environment in Central Spain. A total of 8978 specimens of ixodid ticks were recovered with a mean Parasitization Index of 65.06 ticks/deer. Red deer were infected the whole year round with a summer-spring pattern and two secondary peaks in February and October. The main species was Hyalomma lusitanicum Koch followed by Rhipicephalus bursa Canestrini and Fanzago, Rhipicephalus pusillus Gil Collado, Dermacentor marginatus Sulzer and Ixodes ricinus L. Hyalomma lusitanicum has a complex life cycle in which several generations initiate their cycle at different times throughout the year, most probably lasting more than 1 year. We also describe the ability of nymphs to feed on large ungulates even though their habitual host is wild rabbit.

β-Catenin is required for T-cell leukemia initiation and MYC transcription downstream of Notch1

Notch activation is instrumental in the development of most T-cell acute lymphoblastic leukemia (T-ALL) cases, yet Notch mutations alone are not sufficient to recapitulate the full human disease in animal models. We here found that Notch1 activation at the fetal liver (FL) stage expanded the hematopoietic progenitor population and conferred it transplantable leukemic-initiating capacity. However, leukemogenesis and leukemic-initiating cell capacity induced by Notch1 was critically dependent on the levels of β-Catenin in both FL and adult bone marrow contexts. In addition, inhibition of β-Catenin compromised survival and proliferation of human T-ALL cell lines carrying activated Notch1. By transcriptome analyses, we identified the MYC pathway as a crucial element downstream of β-Catenin in these T-ALL cells and demonstrate that the MYC 3' enhancer required β-Catenin and Notch1 recruitment to induce transcription. Finally, PKF115-584 treatment prevented and partially reverted leukemogenesis induced by active Notch1.

Macroscopic Degeneracy of Zero-Mode Rotating Surface States in 3D Dirac and Weyl Semimetals under Radiation

We investigate the development of novel surface states when 3D Dirac or Weyl semimetals are placed under circularly polarized electromagnetic radiation. We find that the hybridization between inverted Floquet bands opens, in general, a gap, which closes at so-called exceptional points found for complex values of the momentum. This corresponds to the appearance of midgap surface states in the form of evanescent waves decaying from the surface exposed to the radiation. We observe a phenomenon reminiscent of Landau quantization by which the midgap surface states get a large degeneracy proportional to the radiation flux traversing the surface of the semimetal. We show that all of these surface states carry angular current, leading to an angular modulation of their charge that rotates with the same frequency of the radiation, which should manifest in the observation of a macroscopic chiral current in the irradiated surface.