Genetic differentiation across North America in the generalist moth Heliothis virescens and the specialist H. subflexa

The two moth species Heliothis virescens (Hv) and H. subflexa (Hs) are closely related, but have vastly different feeding habits. Hv is a generalist and an important pest in many crops in the USA, while Hs is a specialist feeding only on plants in the genus Physalis. In this study, we conducted a comparative population genetic analysis to assess whether and how generalist and specialist life styles are reflected in differences in population structures. In Hv 98% of the total variation occurred within populations. The overall differentiation (F(ST) ) between regions was 0.006 and even lower between years (0.0039) and hosts (0.0028). Analyses of population structure suggest that all individuals form one genetically homogeneous population, except for at most 12 individuals (6%) that diverged from this cluster. Population homogeneity likely results from the high mobility of Hv and its generalist feeding behaviour. Hs exhibited substantially more population structure. Even though 96% of the total variation was attributable to within-population variability, F(ST) -values between Hs populations were 10 times higher than between Hv populations. Hs populations showed significant isolation by distance. Analyses of Hs population structure suggest at least two subpopulations and thus some degree of metapopulation structure. We speculate that the patchy distribution of Physalis- the exclusive food source of Hs - contributes to differences in population structure between these closely related species. The finding that the specialist shows more population differentiation than the generalist corroborates the notion that host specialization is not an evolutionary dead end but a dynamic trait.

Polycyclic aromatic hydrocarbons in lake sediments from the High Tatras

European alpine lake systems are used as indicators of air quality over the continent. Preliminary data showed high polycyclic aromatic hydrocarbons (PAH) loads in the High Tatras (Eastern Europe) in comparison to other mountain regions. Here, insight on the spatial distribution of PAH is provided from analysis of top-core sediments of 27 alpine lakes distributed along the High Tatras. Top-core sediment concentrations were higher than those in deep-cores, and they were higher than those observed in other European high mountain regions. The PAH profiles were uniform and comparable to those observed in aerosols and snow, indicating that atmospheric deposition was the predominant PAH input pathway to the lakes. Good agreement between estimated atmospheric deposition and sedimentation fluxes was observed. However, in several lakes in the western range higher sediment fluxes may correspond to higher PAH depositions levels. The higher concentrations may also reflect inputs from potential emission source areas.

Analysis of the moderating effect of self-efficacy domains in different points of the dementia caregiving process

INTRODUCTION

Studies analyzing the moderator role of self-efficacy have centered their attention on the relationship between stressors and distress. However, drawing upon the stress and coping model, the moderator effects of self-efficacy may appear in the relationship between other key elements of the stress process.

OBJECTIVES AND METHOD

The purpose of this study was to analyze, in a sample of 167 dementia family caregivers, (1) the moderating effect of self-efficacy for managing behavioral problems on the relationship between frequency of behavioral problems and burden; and (2) the moderating effect of self-efficacy for controlling upsetting thoughts on the relationship between burden and caregivers' distress (depression and anxiety).

RESULTS

While no support has been found for the hypothesis that self-efficacy for managing behavioral problems moderates the relationship between frequency of behavioral problems and burden, our findings support the moderator role of self-efficacy for controlling upsetting thoughts in the relationship between burden and distress. No differences in distress measures are found between caregivers with high and low scores on self-efficacy for controlling upsetting thoughts when they report low levels of burden. However, when the levels of burden are high, caregivers with high self-efficacy for controlling upsetting thoughts report significantly lower levels of distress than caregivers with low self-efficacy for controlling upsetting thoughts.

CONCLUSION

Self-efficacy for controlling upsetting thoughts may be particularly effective for caregivers who report high burden scores, attenuating the impact of burden on caregivers' distress (depression and anxiety).

Mortality risk factors in patients with zygomycosis: a retrospective and multicentre study of 25 cases

AIM

To investigate mortality risk factors in patients with zygomycosis.

PATIENTS AND METHODS

Retrospective case history review of patients diagnosed with proven zygomicosis in 17 centres in Spain. We compared demographics and risk factors in patients who survived, and in those who died.

RESULTS

We identified twenty-five patients with proven zygomycosis. The primary site of infection was rhino-orbito-cerebral (28%) and disseminated (20%) or cutaneous/soft infections (20%) of the patients. Eleven patients (44%) received preemptive or empirical antifungal treatment; of these patients, 4 received liposomal amphotericin B, 1 received amphotericin B lipid complex, and 6 received other antifungals. The overall mortality rate was 72%. In the univariate analysis factors associated with an increased risk of death were the presence of a haematological malignancy (P=.03), neutropenia (P=.03) and monocytopenia (P=.008).

CONCLUSION

Our study supports previous research that has documented a high mortality rate among patients with invasive zygomycosis, especially among those with an underlying haematological malignancy, and the need for a rapid initiation of an effective antifungal treatment.

[Histopathological findings and biomarker analysis in cutaneous graft-versus-host disease ]

Graft-versus-host disease (GVHD) remains the greatest source of morbidity-mortality in allogenic transplant patients. Although in most cases the more easily obtainable clinical and laboratory test parameters suffice to confirm the diagnosis and establish the stage of the disease biopsies of the affected organ are sometimes needed. At present there is great Interest in the study of factors allowing a prognosis of the course and type of response to treatment in patients with CVHD. In this sense, It would be necessary to objectively Identify and validate biomarkers capable of predicting biological or pathological processes in patients with cVHD. To this effect we have performed serial analyses of skin tissue using peripheral blood and tissue biomarkers in a prospective observational study conducted in three transplant centers. The still preliminary results Indicate that certain histopathological findings classically attributed to CVHD ore also seen in patients not clinically affected by the disease--this probably being related to other physiopathological phenomena occurring during transplantation. The study of these findings, combined with biomarker analysis, will allow improved understanding of the underlying etiopathogenesis, as well as the definition of new diagnostic, prognostic and response-evaluating criteria.

[Carotid revascularisation using angioplasty and stent in 134 consecutive cases in a reference hospital: a risky technique?]

INTRODUCTION

Carotid revascularisation (CR) using angioplasty and stent (ASC) is an effective procedure in the prevention of ischaemic stroke, but with a controversial morbidity and mortality in the different studies conducted in this field.

METHODS

The results of the ASCs performed in the Virgen de la Arrixaca University Hospital (Murcia) between January 2006 and April 2009 were analysed (epidemiology, indication, grade of residual stenosis and procedure complications). All patients subjected to ASC were pre-selected and followed up by neurologists, and they followed a strict medical protocol for performing the procedure. All ASCs were performed by a team consisting of two surgeons, an anaesthetist and a nurse.

RESULTS

A total of 134 ASC were performed. The mean age of our patients was 72.7 years, with the large majority (75%) being male. The most prevalent diseases were, high blood pressure (81%), smoking (66.4%), and diabetes (38.1%). The most common indications for CR were symptomatic carotid stenosis with a level of stenosis of 75-99%, either in the left (33.6%) or right (32.1%), followed by asymptomatic stenosis combined with risk factors (11.2% in the left side and 10.4% in the right side). A level of stenosis less than 30% was achieved in 132 of the 134 ASC (98.5%). performed. Five patients (3.7%) had complications associated with the procedure, of which four were different clinical presentations of a re-perfusion syndrome and one an asymptomatic thrombosis of the stent.

CONCLUSIONS

ASC is a complex technique that must be performed by appropriately trained specialists. The performing a minimum number of procedures per year and an admission protocol controlled by Neurology are essential conditions for a low rate of complications. Under these conditions, the morbidity and mortality of the technique is no higher than that of endarterectomy.

[Quantitative salivary gland scintigraphy in head and neck cancer patients following radiotherapy]

OBJECTIVE

To assess the role of quantitative salivary gland scintigraphy (SGS) in the detection of functional impairment of salivary glands in patients with head and neck cancer treated with radiotherapy (RT).

MATERIAL AND METHODS

We studied 19 patients (17 men), mean age 62.4 years (44-75). Three studies were performed to each patient: baseline, 3 and 18 months after RT. SGS was acquired for 25 minutes following injection of 3.7 MBq/kg of (99m)Tc-pertechnetate with lemon juice at the end of minute 15. Excretion fraction (EF), counts per minute/pixel/MBq (CMPM) and uptake percentage were obtained from time-activity curves from ROIs placed over parotid (PG) and submandibular glands (SMG) and related to the doses received by the PG.

RESULTS

EF showed a significant reduction from the baseline to the 3 months study (p<0.001) for the PG and SMG and from the baseline to the 18 months study for the SMG (p<0.001). A significant improvement of EF was seen from the 3 months to the 18 months study for the PG (p<0.05). CMPM did not change significantly from the baseline to the 3 months and 18 months studies for the PG and showed a significant reduction (p<0.01) for the SMG from the baseline to 18 months study. The uptake percentage did not change significantly between studies. A moderate association was observed between the doses to PG and the 3m study parameters.

CONCLUSIONS

EF was more sensitive than uptake in assessing post-RT impairment of salivary function. In addition, it reflected functional recovery of parotid glands over time.

[Epidemiology and clinical presentation of Panton-Valentin leukocidin positive methicillin-resistant Staphylococcus aureus]

INTRODUCTION

the aim of our study was to review the epidemiology and clinical manifestations of infections due to Panton-Valentine leukocidin-positive methicillin-resistant Staphylococcus aureus (PVL-MRSA).

MATERIAL AND METHODS

Medical history of patients infected by MRSA-PVL admitted to our hospital from January 2007 to July 2009 was reviewed. PVL and the type of cromosomic cassette were determined in all strains by PCR.

RESULTS

A total of 37 cases were included. Seventy percent were males and the median age was 39 years. Sixtytwo percent were Spanish, 14 (37.8%) were HIV-positive and 11 (29.7%) were homosexual. The source of the infection was the skin and soft tissue in 36 cases and pneumonia in 1. Sixteen patients were hospitalized, 5 had bacteremia and 5 developed septic metastasis. The relapse rate was 24% (9 cases). The prevalence during the study period was 11.2% of all MRSA isolated (37 out of 329). All the strains had a cromosomic cassette type IV and were susceptible to cotrimoxazole, rifampin, vancomyin, daptomycin and linezolid. The MIC of vancomycin, measured by E-test, was ≥ 1.5 mg/L in 28 out of 34 cases (82.3%).

CONCLUSIONS

Eleven percent of the MRSA strains isolated in our hospital are PVL positive. In general, skin and soft tissue infections are the most common and bacteremia or septic metastasis are frequent. In contrast to previous Spanish studies, more cases are observed in patients born in Spain and the infections are more severe.

Electrical and pharmacological manipulations of the nucleus accumbens core impair synaptic plasticity in the dentate gyrus of the rat

The interest on the physiology of the nucleus accumbens (NAcc) has grown in recent years given its relationship to addictive behaviours, and the possibility to treat them by interacting with NAcc function. We have shown that the prior stimulation of the core region blocks induction of long-term potentiation (LTP) at the dentate gyrus in anaesthetized rats, while the shell facilitated it. In the present study we have confirmed and expanded those results testing the effects of core and shell stimulation in freely moving rats, as well as the effect of blocking D1 receptors in the NAcc. Our results show that shell stimulation had no effect on baseline recordings of the field excitatory postsynaptic potential (fEPSP) or the population spike amplitude (PSA) for 24 h. Core stimulation did not modify baseline-fEPSP, but significantly depressed PSA up to 8 h. LTP maintenance was not modified; neither by core nor shell stimulation after its induction, but LTP induction was impaired (both in the fEPSP and PSA) by core stimulation 15 min before induction. Shell stimulation showed a slight facilitating effect. Previous, topical application of a dopaminergic-receptor antagonist (SCH23390) into the NAcc produced a significantly depressed baseline fEPSP and PSA, as well as LTP measured in both components of the evoked potentials. Our results confirm a dual role of stimulation of NAcc sub-regions on hippocampal baseline synaptic transmission, and LTP induction when activated before induction. In contrast, stimulation of the NAcc had no influence on an already ongoing dentate gyrus LTP. A role for dopaminergic innervation to the NAcc, modifying susceptibility for synaptic plasticity outside the NAcc is also suggested by our results.