Attempts to use breeding approaches in Aedes aegypti to create lines with distinct and stable relative Wolbachia densities.

Wolbachia is an insect endosymbiont being used for biological control in the mosquito Aedes aegypti because it causes cytoplasmic incompatibility (CI) and limits viral replication of dengue, chikungunya, and Zika viruses. While the genetic mechanism of pathogen blocking (PB) is not fully understood, the strength of both CI and PB are positively correlated with Wolbachia densities in the host. Wolbachia densities are determined by a combination of Wolbachia strain and insect genotype, as well as interactions with the environment. We employed both artificial selection and inbreeding with the goal of creating lines of Ae. aegypti with heritable and distinct Wolbachia densities so that we might better dissect the mechanism underlying PB. We were unable to shift the mean relative Wolbachia density in Ae. aegypti lines by either strategy, with relative densities instead tending to cycle over a narrow range. In lieu of this, we used Wolbachia densities in mosquito legs as predictors of relative densities in the remaining individual's carcass. Because we worked with outbred mosquitoes, our findings indicate either a lack of genetic variation in the mosquito for controlling relative density, natural selection against extreme densities, or a predominance of environmental factors affecting densities. Our study reveals that there are moderating forces acting on relative Wolbachia densities that may help to stabilize density phenotypes post field release. We also show a means to accurately bin vector carcasses into high and low categories for non-DNA omics-based studies of Wolbachia-mediated traits.

SARS-CoV-2 transmission dynamics in the urban-rural interface.

OBJECTIVES: As the world responds to the coronavirus outbreak, the role of public health in ensuring equitable health care that considers the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) dynamics in rural communities is still a challenge. The same suppression and mitigation measures have been implemented homogeneously, ignoring the differences between urban and rural areas. We propose an epidemiological model and simulate the dynamics of SARS-CoV-2 in urban and rural areas considering the interaction between these regions. STUDY DESIGN: This was a population modeling study. METHODS: A compartmental epidemiological model was formulated to simulate the transmission of SARS-CoV-2 in urban and rural areas. We use the model to investigate the impact of control strategies focused on the urban-rural interface to contain the epidemic size of SARS-CoV-2 in rural areas. RESULTS: Considering five different levels for the exposition rate in urban areas and keeping intrarural and urban-rural exposition rates fixed, the preventive measures reduce the size and delay the peak for the urban infectives. The response of infected individuals and cumulative deaths in rural areas upon changes in the urban dynamics was small but not negligible. On the other hand, preventive measures focused on the urban-rural interface impact the number of infected individuals and deaths in rural areas. CONCLUSIONS: The maintenance of SARS-CoV-2 in rural areas depends on the interaction of individuals at the urban-rural interface. Thus, restrictive measures established by the governments would not be required within rural areas. We highlight the importance of focused preventive measures on the urban-rural interface to reduce the exposure and avoid the transmission of SARS-CoV-2 to rural communities.

Effect of clay and guishe-ash as substrate on Lycopersicon esculentum germination and production.

The effect of biomass ash and clay on tomato plants (Lycopersicon esculentum) in greenhouse conditions from germination to production was studied. Biomass ash is a waste obtained from thermal treatment of guishe (a by-product of natural fiber), and clay is collected from local soils. Several trials were performed to assess the influence of the addition of clay and guishe-ash on seeds germination, seedling growth, and production yield. The decrease in the values of these variables was considered an indicator of toxicity. The obtained results showed that based clay/ash materials positively affect germination (average ∼90% and six materials allow obtaining 90%) and seedlings growth (an increase of ∼20% in height and more than 50% in fresh air corpuscular weight). However, applying these materials on the production stage induces minor positive effects on fruit diameter, locule number, pericarp thickness, and the number of seeds per fruit. Also, adverse effects (first harvest yield, number of fruits, fresh mass of ripe fruits, lycopene content) were observed. To valorize biomass ash, its combination with other materials such as clay could be an alternative to improve tomato production.

The concern to attend the growing demand for food has promoted the use of different kinds of materials as enhancers of plant growth and crop productivity. Among the materials that have been applied in crops are the wastes of biomass thermochemical processes, such as biochar and ashes. This work highlights the importance of evaluating the effect of applying a residue (guishe-ash) to a crop before promoting its use.

Percutaneous tibial nerve stimulation in patients with severe low anterior resection syndrome: randomized clinical trial.

BACKGROUND: Treatment of low anterior resection syndrome (LARS) is challenging. Percutaneous tibial nerve stimulation (PTNS) can improve select bowel disorders. An RCT was conducted to assess the efficacy of PTNS compared with sham stimulation in patients with severe LARS. METHOD: This was a multicentre, double-blind RCT. Patients with major LARS score were allocated to receive PTNS or sham therapy (needle placement simulation without nerve stimulation). The study included 16 sessions of 30 min once a week for 12 consecutive weeks, followed by four additional sessions once a fortnight for the following 4 weeks. The primary endpoint was efficacy of PTNS defined by the LARS score 12 months after treatment. Secondary endpoints included faecal incontinence, quality of life (QoL), and sexual function. RESULTS: Between September 2016 and July 2018, 46 eligible patients were assigned randomly in a 1 : 1 ratio to PTNS or sham therapy. Baseline characteristics were similar. LARS scores were reduced in both groups, but only patients who received PTNS maintained the effect in the long term (mean(s.d.) score 36.4(3.9) at baseline versus 30.7(11.5) at 12 months; P = 0.018; effect size -5.4, 95 per cent c.i. -9.8 to -1.0), with a mean reduction of 15.7 per cent at 12-month follow-up. The faecal incontinence score was improved after 12 months in the PTNS group (mean(s.d.) score 15.4(5.2) at baseline versus 12.5(6.4) at 12 months; P = 0.018). No major changes in QoL and sexual function were observed in either group. There was no therapy-associated morbidity. Three patients discontinued the study, but none owing to study-related issues. CONCLUSION: PTNS has positive effects in some patients with major LARS, especially in those with faecal incontinence. Registration number: NCT02517853 (http://www.clinicaltrials.gov).

Comparison of the third molar maturity index (I3M) between left and right lower third molars to assess the age of majority: a multi-ethnic study sample.

The diagnostic accuracy of the I3M to assess the legal age of 18 years has already been tested in several specific-population samples. The left lower third molar has been extensively used for discriminating between minors and adults. This research aimed to compare the usefulness of lower third molar maturity indexes, from both left and right side (I3ML and I3MR), in samples originating from four distinct continents in order to examine possible differences in their accuracy values. For this purpose, a sample of 10,181 orthopantomograms (OPGs), from Europe, Africa, Asia and America, was analysed and previously scored in other studies. The samples included healthy subjects with no systemic disorders with both third molars and clear depicted root apices. Wilcoxon Signed Rank test for left and right asymmetry did not show any significant differences. Data about sensitivity, specificity, predictive values, likelihood ratio and accuracy were pooled together and showed similar results for I3ML and I3MR, respectively. In addition, all these quantities were high when only the I3MR was considered to discriminate between adults and minors. The present referable database was the first to pool third molar measurements using panoramic radiographs of subjects coming from different continents. The results highlighted that both I3ML and I3MR are reliable indicators for assessing the legal age of 18 years old in those jurisdictions where this legal threshold has been set as the age of majority.

Management of early gestations with low beta-human chorionic gonadotropin conceived by assisted reproductive technologies: performance of M4 predictive model.

OBJECTIVES: To assess the safety and performance of the M4 model for classifying as high risk or low risk for ectopic pregnancy (EP) pregnancies conceived by assisted reproductive technologies (ART) that present with low beta-human chorionic gonadotropin (ß-hCG) concentration in early gestation. METHODS: This was a prospective cohort study of 243 pregnancies conceived by ART with low ß-hCG levels (5-50 IU/L) at 4 + 0 to 4 + 2 weeks' gestation. After subsequent ß-hCG testing at 48 h, pregnancies were classified according to the M4 model into the following categories: (i) high risk, probable EP/persistent pregnancy of unknown location (PPUL), when the risk for EP was ≥ 5%; (ii) low risk, probable intrauterine pregnancy (IUP), when the risk of EP was < 5% and the likelihood of IUP was greater than that of a failed pregnancy of unknown location (FPUL); and (iii) low risk, probable FPUL, when the risk of EP was < 5% and the likelihood of a FPUL was greater than that of an IUP. The predictive performance of the M4 model for EP and its ability to discriminate between high- and low-risk pregnancies was assessed using the final pregnancy outcome at 11 to 13 weeks of gestation as reference, which was classified as EP/PPUL, FPUL or IUP. RESULTS: The sensitivity and specificity of the M4 model in detecting a high-risk pregnancy (EP/PPUL) were 60.0% (95% CI, 43.6-74.4%) and 79.8% (95% CI, 73.8-84.7%), respectively. The area under the receiver-operating-characteristics curve of the M4 model for discriminating between high-risk and low-risk (FPUL/IUI) pregnancies was 0.72 (95% CI, 0.62-0.81). The model had a positive likelihood ratio of 2.97 (95% CI, 2.03-4.36) and a negative likelihood ratio of 0.50 (95% CI, 0.33-0.76). The kappa index was 0.30 (95% CI, 0.16-0.43), indicating a low degree of agreement between the model classification and the final diagnosis. No serious adverse events related directly to the application of the M4 model were observed, although 14 pregnancies classified ultimately as high risk had been categorized initially as low risk by the M4 model. Of these, seven resolved with expectant management, five with methotrexate (MTX) and two required laparoscopic surgery (one after failure of medical treatment with MTX and one after deviation from the follow-up protocol). There were no cases of EP/PPUL with additional complications or need for blood or other blood product transfusion. Of the 243 ART pregnancies with low ß-hCG concentration in early gestation, only 47 (19.3%) had an IUP, half (24/47) of which had an early miscarriage, resulting in only 9.5% (23/243) cases having an ongoing pregnancy. CONCLUSIONS: Application of the M4 model in pregnancies conceived by ART with low ß-hCG concentration in early gestation showed limited capacity in classifying them as being at low or high risk for EP, therefore, its use in pregnancies of this type is not recommended. No serious adverse events or complications related to the use of the model were observed. These pregnancies have a low probability of ending in an IUP as well as a high rate of early miscarriage. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Analysis of phenanthrene degradation by Ascomycota fungi isolated from contaminated soil from Reynosa, Mexico.

Polycyclic aromatic hydrocarbons (PAHs) are organic compounds generated mainly by anthropogenic sources. They are considered toxic to mammals, since they have carcinogenic, mutagenic and genotoxic properties, among others. Although mycoremediation is an efficient, economical and eco-friendly technique for degrading PAHs, the fungal degradation potential of the phylum Ascomycota has not been widely studied. In this work, we evaluated different fungal strains from the polluted soil of 'La Escondida' lagoon in Reynosa, Mexico to know their potential to degrade phenanthrene (PHE). Forty-three soil isolates with the capacity to grow in the presence of PHE (0·1% w/v) were obtained. The fungi Aspergillus oryzae MF13 and Aspergillus flavipes QCS12 had the best potential to degrade PHE. Both fungi germinated and grew at PHE concentrations of up to 5000 mg l-1 and degraded 235 mg l-1 of PHE in 28 days, with and without an additional carbon source. These characteristics indicate that A. oryzae MF13 and A. flavipes QCS12 could be promising organisms for the remediation of sites contaminated with PAHs and detoxification of recalcitrant xenobiotics.

Prognostic factors in patients with primary cutaneous anaplastic large cell lymphoma: a multicentric, retrospective analysis of the Spanish Group of Cutaneous Lymphoma.

BACKGROUND: Reliable prognostic factors for patients with primary cutaneous anaplastic large cell lymphoma (PCALCL) are lacking. OBJECTIVE: To identify prognostic factors for specific survival in patients with PCALCL. METHODS: Using the convenience sampling method, patients with PCALCL diagnosed from May 1986 to August 2017 in 16 University Departments were retrospectively reviewed. RESULTS: One hundred eight patients were included (57 males). Median age at diagnosis was 58 years. All of them showed T1-3N0M0 stages. Seventy per cent of the cases presented with a solitary lesion, mostly at the limbs. Complete response rate after first-line treatment was 87%, and no advantage was observed for any of them (surgery, radiotherapy, chemotherapy or other approaches). Nodal and visceral progression rate was 11% and 2%, respectively. 5-year specific survival (SSV) reached 93%; 97% for T1 patients and 84% for T2/T3 patients (P = 0.031). Five-year SSV for patients developing early cutaneous relapse was 64%; for those with late or no relapse, 96% (P = 0.001). Estimated median SSV for patients showing nodal progression was 103 months (95% CI: 51-155 months); for patients without nodal progression, estimated SSV did not reach the median (P < 0.001). Nodal progression was an independent predictive parameter for shorter survival (P = 0.011). CONCLUSION: Multiple cutaneous lesions at presentation, early skin relapse and nodal progression portrait worse prognosis in patients with PCALCL.

Factors associated with impairment in gait speed in older people with clinically normal gait. A cross-sectional study.

BACKGROUND: Health professionals commonly use gait speed in the evaluation of functional status in older people. However, only a limited number of studies have assessed gait speed in the absence of disorders of gait, using confounding factors and exclusion criteria coming from studies conducted in younger people. Our study aims to analyse which factors are associated with gait speed in older people with normal clinical gait. METHODS: An observational cross-sectional study was conducted in 119 community-dwelling residents without relevant comorbidities (Charlson index < 2), preserved function (Barthel > 85) and normal gait by visual exploration. Exclusion criteria included suffering from any illness that could modify the characteristics of gait, terminal status or the presence of an acute medical illness in the past 3 months. We used a stepwise linear regression of several variables (sociodemographic characteristics, cognition, body composition, drugs, falls, sarcopenia, frailty and physical activity) on 6-metre gait speed. RESULTS: The mean age was 78 years (range 70-96 years) and 71.4% were women. Variables that remained associated with gait speed in the multivariate final model were age (B = - 0.020, p < 0.001); gender (B = - 0.184, p < 0.001); waist-to-height ratio (B = - 0.834, p = 0.002); number of falls (B = - 0.049, p = 0.003) and the number of Fried's frailty criteria (B = - 0.064, p = 0.019). CONCLUSION: Falls, frailty and the waist-to-height ratio modify gait speed in older people with normal gait. Studies analysing the potential effect of several factors on gait speed should consider them as confounding factors.

Incidence of milk leakage after dry-off in European dairy herds, related risk factors, and its role in new intramammary infections.

The incidence of milk leakage (ML) after dry-off (DO) and related risk factors was studied in 1,175 dairy cows from 41 commercial herds in 8 European countries: Belgium, Czech Republic, Denmark, France, Germany, Italy, the Netherlands, and Spain. Milk leakage was assessed twice for 30 s each during 3 visits at 20 to 24 h, 30 to 34 h, and 48 to 52 h after DO. Information related to dry-cow management and udder health was collected at herd and cow level, including individual somatic cell count (ISCC) from test-day controls and occurrence of clinical mastitis cases from DO until 30 d in lactation. Mixed-effect logistic regression analyses were used to identify possible risk factors for ML and to study the association between ML and new intramammary infections. Intramammary infections were defined as clinical mastitis cases during the dry period and in the first 30 d in lactation or a rise in ISCC from before to after the dry period (threshold: 200,000 cells/mL) or both. Milk leakage was observed in 24.5% of the cows between 20 and 52 h after DO, where the herd incidence varied between 0.0 and 77.8%. The reduction in number of milkings in the weeks before DO had statistically significant effect on the ML incidence. When the milking frequency was reduced from 3 times/d to 2 or maintained at twice a day, cows had 11 (95% CI = 3.43-35.46) or 9 (95% CI = 1.85-48.22) times higher odds of leaking milk, respectively, compared with cows where the milking frequency was reduced from twice to once a day. Also, the milk production 24 h before DO was associated with ML incidence. Hence, cows with a milk production between 13 and 21 L or above 21 L had 2.3 (95% CI = 1.48-3.53) and 3.1 (95% CI = 1.79-5.3) times higher odds of leaking milk, respectively, compared with cows with a milk production below 13 L. A higher ML incidence was present in the group of cows with an average ISCC in the last 3 mo before DO ≥200,000 cells/mL (odds ratio = 1.7; 95% CI = 1.13-2.41) compared with cows with an average ISCC <100,000 cells/mL. Quarters with ML tended to have 2.0 times higher odds of developing clinical mastitis compared with quarters not leaking milk. Cows with ML tended to have 1.5 times higher odds of intramammary infections (i.e., an increase of ISCC or clinical mastitis) compared with cows without ML.

Evaluation of anthelmintic drugs against egg development of rumen flukes recovered from cattle raised in the humid tropics of Mexico.

Paramphistomosis is a parasitic disease endemic in ruminants nearly worldwide. In the present study, an in vitro screening of the main anthelmintics used in Mexico was carried out to determine the mean lethal dose for rumen fluke eggs from cattle in a humid, warm region. Rumen flukes were obtained from cattle slaughtered in the states of Tabasco and Chiapas in Mexico. Eggs were collected using a 37-µm sieve and quantified. Then, an in vitro incubation study was performed: 100 eggs were placed into the wells of polystyrene microtiter plates. Anthelmintic products were tested on the eggs at concentrations ranging from 0.0015 to 3.0 mg/ml for rafoxanide, 0.0025 to 10.20 mg/ml for nitroxinil and 0.0015 to 3 mg/ml for closantel to determine the median lethal dose (LD50) and maximum lethal dose (LD99). A control group (water) was included in each plate. Three different species of rumen flukes (Calicophoron brothriophoron, Calicophoron clavula and Paramphistomum cervi) belonging to five isolates were identified. Nitroxinil had the highest efficacy against rumen fluke eggs, with an LD50 of 0.11 to 65 µg/ml, whereas rafoxanide showed the lowest efficacy with an LD50 ranging from 500 to 1713 µg/ml. Closantel showed high variability in the LD50 among the different analysed isolates (17 to 122 µg/ml). The evaluated flukicidal drugs presented differential efficacy against the development of rumen fluke eggs. The efficacy of the drugs will vary depending on the geographical area of origin of the animals.

Resistive switching control for conductive Si-nanocrystals embedded in Si/SiO2 multilayers.

In this paper, we report on the enhanced control of resistive switching in multilayer Si/SiO2 structures, which permit the formation of Si nanocrystals with a typical size of 5.88 nm and overall good shape homogeneity. The deposition of a different number of Si and SiO2 bilayers (6, 8 and 10) allowed control of SET/RESET voltages in negative bias ranges 4.5-10 V and 6.3-13 V for six- and ten-bilayer devices, respectively. The corresponding resistance ratio between ON/OFF states varied in the ranges 107-105 for the aforementioned number of bilayers. Based on the result of XPS measurements, we suggest that the resistive switching in the studied system occurs due to the formation and annihilation of Si-Si and Si-O bonds, which serve as conductive pathways and isolating material, respectively.

Factors associated with pregnancy desire among adolescent women in five Latin American countries: a multilevel analysis.

OBJECTIVE: To explore demographic, socio-economic, and reproductive factors associated with pregnancy desire among adolescents in five Latin American countries. DESIGN: Secondary analysis using nationally representative, cross-sectional data from UNICEF Multiple Indicator Cluster Surveys (MICS). SETTING: Cuba, the Dominican Republic, El Salvador, Mexico, and Panama. POPULATION: Adolescents 15-19 years old who were pregnant or mothers (n = 4207). METHODS: Chi-square tests, simple linear regressions, and multilevel Poisson regression models were used to estimate associations between individual- and country-level factors associated with pregnancy desire among adolescents. MAIN OUTCOME MEASURES: Desire for pregnancy among adolescents who were pregnant or had given birth in the last 2 years. RESULTS: The proportion of adolescents who reported they desired their last pregnancy ranged from 79.3% in Cuba to 37.6% in Panama; approximately half the adolescents in Mexico, El Salvador, and the Dominican Republic desired their last pregnancy. The multilevel analysis shows that pregnancy desire was more likely among adolescent women who were less educated [prevalence ratio (PR) = 0.97, 95% confidence interval (CI) 0.96-0.98], older (PR = 1.39, 95% CI 1.04-1.09), married or cohabiting with a partner (PR = 0.70, 95% CI 0.53-0.93), and had low parity (PR = 0.67, 95% CI 0.58-0.76). CONCLUSIONS: Adolescents with less education, who are older, married or cohabiting, and with low parity were more likely to desire their pregnancy. These data constitute evidence that, in conjunction with qualitative and implementation research, can be used to better design services for adolescents so they can exercise their sexual and reproductive rights, and plan healthier and more satisfying futures. FUNDING: All the databases used on the performance of this study are open access. We did not receive any funding for the present analysis. TWEETABLE ABSTRACT: Parity and marital status showed the strongest association with adolescent pregnancy desire in five Latin American countries.

First-line treatment in lymphomatoid papulosis: a retrospective multicentre study.

BACKGROUND: Data regarding response to treatment in lymphomatoid papulosis (LyP) are scarce. AIM: To assess the daily clinical practice approach to LyP and the response to first-line treatments. METHODS: This was a retrospective study enrolling 252 patients with LyP. RESULTS: Topical steroids, methotrexate and phototherapy were the most common first-line treatments, prescribed for 35%, 20% and 14% of the patients, respectively. Complete response (CR) was achieved in 48% of treated patients. Eczematous lesions significantly increased relative risk (RR) of not achieving CR (RR = 1.76; 95% CI 1.16-2.11). Overall median time to CR was 10 months (95% CI 6-13 months), and 78% of complete responders showed cutaneous relapse; both results were similar for all treatment groups (P > 0.05). Overall estimated median disease-free survival (DFS) was 11 months (95% CI 9-13 months) but DFS for patients treated with phototherapy was 23 months (95% CI 10-36 months; P < 0.03). Having the Type A LyP variant (RR = 2.04; 95% CI 0.96-4.30) and receiving a first-line treatment other than phototherapy (RR = 5.33; 95% CI 0.84-33.89) were significantly associated with cutaneous early relapse. Of the 252 patients, 31 (13%) had associated mycosis fungoides unrelated to therapeutic approach, type of LyP or T-cell receptor clonality. CONCLUSIONS: Current epidemiological, clinical and pathological data support previous results. Topical steroids, phototherapy and methotrexate are the most frequently prescribed first-line treatments. Although CR and cutaneous relapse rates do not differ between them, phototherapy achieves a longer DFS. Presence of Type A LyP and use of topical steroid or methotrexate were associated with an increased risk of early relapse.

Attentional influences on memory formation: A tale of a not-so-simple story.

Is there a learning mechanism triggered by mere expectation violation? Is there some form of memory enhancement inherent to an event mismatching our predictions? Across seven experiments, we explore this issue by means of a validity paradigm. Although our manipulation clearly succeeded in generating an expectation and breaking it, the memory consequences of that expectation mismatch are not so obvious. We report here evidence of a null effect of expectation on memory formation. Our results (1) show that enhanced memory for unexpected events is not easily achieved and (2) call for a reevaluation of previous accounts of memory enhancements based on prediction error or difficulty of processing. Limitations of this study and possible implications for the field are discussed in detail.

Factors associated with ever use of mammography in a limited resource setting. A mixed methods study.

OBJECTIVE: To evaluate facilitators and barriers influencing mammography screening participation among women. DESIGN: Mixed methods study. SETTING: Three hospital catchment areas in Hidalgo, Mexico. PARTICIPANTS: Four hundred and fifty-five women aged 40-69 years. INTERVENTION: Three hundred and eighty women completed a survey about knowledge, beliefs and perceptions about breast cancer screening, and 75 women participated in semi-structured, in-person interviews. Survey data were analyzed using logistic regression; semi-structured interviews were transcribed and analyzed using elements of the grounded theory method. MAIN OUTCOME MEASURE: Women were categorized as never having had mammography or having had at least one mammogram in the past. RESULTS: From survey data, having had a Pap in the past year was associated with ever having had breast screening (odds ratio = 2.15; 95% confidence interval 1.30-3.54). Compared with never-screened women, ever-screened women had better knowledge of Mexican recommendations for the frequency of mammography screening (49.5% vs 31.7% P < 0.001). A higher percentage of never-screened women perceived that a mammography was a painful procedure (44.5% vs 33.8%; P < 0.001) and feared receiving bad news (38.4% vs 22.2%; P < 0.001) compared with ever-screened women. Women who participated in semi-structured, in-person interviews expressed a lack of knowledge about Mexican standard mammographic screening recommendations for age for starting mammography and its recommended frequency. Women insured under the 'Opportunities' health insurance program said that they are referred to receive Pap tests and mammography. CONCLUSIONS: Local strategies to reduce mammogram-related pain and fear of bad news should work in tandem with national programs to increase access to screening.

Contrasting thermal strategies of montane Neotropical bats at high elevations.

In the Neotropics, captive vespertilionid bats substantially reduce their metabolic rate at low ambient temperatures, similar to their temperate counterparts, whereas the ability of phyllostomids to lower metabolic rate seems to be more limited, even in mountain species. Nevertheless, field data on the thermal behaviour of syntopic individuals from these two families is lacking. Consequently, we aimed to test whether torpor was more common and deeper in vesper bats compared to leaf-nosed bats by studying skin temperature (Tsk) variation in individuals experiencing the same environmental conditions at a mountain area. Bats experienced ambient temperatures below 15 °C. Average Tsk was 10 °C in Myotis oxyotus gardneri (Vespertilionidae) during the day, while Sturnira burtonlimi (Phyllostomidae) regulated diurnal Tsk above 30 °C. Constant food availability may explain why diurnal Sturnira burtonlimi pay the high energetic cost required to remain normothermic and to defend a wide Ta-Tsk gap but further studies are needed to elucidate additional strategies that may be employed by these bats to reduce the energetic demands of normothermy. Our study shows that the contrasting thermal strategies and torpor use adopted by vespertilionid insectivores and phyllostomid frugivores in captive settings also occur in free-ranging conditions, thus providing a basis to develop further studies with predictions more accurately rooted in field data.

Quantitative real-time PCR (qPCR) for the detection and quantification of dactylogyrid parasites infecting Lutjanus guttatus.

Severe infections of the spotted rose snapper Lutjanus guttatus resulting from dactylogyrid monogeneans present a risk to aquaculture. Currently, the diagnosis of this infection requires the morphological identification and manual quantification of parasites. Based on the characterization of the 28S rRNA gene of dactylogyrid species present in L. guttatus, specific primers were designed for real-time polymerase chain reaction (qPCR) using EvaGreen® chemistry. The standard curve method estimated the number of dactylogyrids accurately. A total of 85 gill samples from cage-cultured fish infected with dactylogyrids were analysed. The estimated number of dactylogyrids using this molecular method was very similar to the manual count that was performed initially. The standardized qPCR approach will be helpful as a complementary method for the early routine monitoring of dactylogyrid infections and for epidemiological studies in which a high number of fish must be studied.

The legacy of Columbus in American horse populations assessed by microsatellite markers.

Criollo horse populations descend from horses brought from the Iberian Peninsula over the period of colonization (15th to 17th century). They are spread throughout the Americas and have potentially undergone genetic hybridization with other breeds in the recent past. In this study, 25 autosomal microsatellites were genotyped in 50 horse breeds representing Criollo populations from 12 American countries (27 breeds), breeds from the Iberian Peninsula (19), one breed each from France and Morocco and two cosmopolitan horse breeds (Thoroughbred and Arabian). The genetic relationships among breeds identified five clusters: Celtic; Iberian; North American with Thoroughbred influence; most Colombian breeds; and nearly all other Criollo breeds. The group of "all other Criollo breeds" had the closest genetic relationship with breeds originating from the Iberian Peninsula, specifically with the Celtic group. For the whole set of Criollo breeds analysed, the estimated genetic contribution from other breeds was approximately 50%, 30% and 20% for the Celtic, Iberian and Arab-Thoroughbred groups, respectively. The spatial distribution of genetic diversity indicates that hotspots of genetic diversity are observed in populations from Colombia, Ecuador, Brazil, Paraguay and western United States, possibly indicating points of arrival and dispersion of Criollo horses in the American continent. These results indicate that Criollo breeds share a common ancestry, but that each breed has its own identity.