Multiple paternity in a wild population of Armadillidium vulgare: influence of infection with Wolbachia?

Female multiple mating has been extensively studied to understand how nonobvious benefits, generally thought to be of genetic nature, could overcome heavy costs such as an increased risk of infection during mating. However, the impact of infection itself on multiple mating has rarely been addressed. The interaction between the bacterium Wolbachia and its terrestrial crustacean host, Armadillidium vulgare, is a relevant model to investigate this question. In this association, Wolbachia is able to turn genetic males into functional females (i.e. feminization), thereby distorting the sex ratio and decreasing the number of available males at the population scale. Moreover, in A. vulgare, females have been shown to mate multiply under laboratory conditions and males prefer uninfected females over infected ones. Additionally, different Wolbachia strains are known to infect A. vulgare and these strains differ in their transmission rate and virulence. All these elements suggest a potential impact of different Wolbachia strains on multiple mating. To investigate this assumption, we collected gravid females in a wild A. vulgare population harbouring both uninfected females and females infected with one of two different Wolbachia strains (wVulM and wVulC) and performed paternity analyses on the obtained broods using microsatellite markers. We demonstrate that (i) multiple paternity is common in this wild population of A. vulgare, with a mean number of fathers of 4.48 ± 1.24 per brood and (ii) females infected with wVulC produced broods with a lower multiple paternity level compared with females infected with wVulM and uninfected ones. This work improves our knowledge of the impact of infections on reproductive strategies.

Perioperative pain management in hip arthroscopy; what options are there?

Hip arthroscopy is a fast growing orthopedic field of expertise. As in any field of surgery adequate postoperative pain management regimes are of utmost importance. The purpose of this review is to provide an overview of current knowledge on anesthetic options for perioperative pain management for hip arthroscopy. We searched the Pubmed/Medline and Embase database for literature and included 10 studies for our analysis. Because of the variety of pain scales and different ways of measured pain no meta-analysis could be performed and a descriptive review is performed. There are several types of pain regimens that can mostly be divided in two groups: local anesthetics and nerve blocks. Included studies show a rather large variation in reported visual analogue scale scores, post anesthesia care unit admission time and opioid usage. There are several anesthetic options available for hip arthroscopy. Different studies use different dosages, anesthetic regimens and different protocols; this partly explains the differences between studies with similar techniques. Peripheral nerve blocks seems promising but regarding current literature no clear recommendation can be made about what the best perioperative pain management option is, an overview of all reported techniques is given.

Hip arthroscopy in obese, a successful combination?

Discussion persists about the outcome and results of hip arthroscopy in obese patients. Hip arthroscopy gained popularity over time. A current discussion is if obese patients can reach similar results after surgery compared with non-obese. To our knowledge, this is the first systematic review of literature about hip arthroscopy and obesity. We searched the Pubmed/Medline databases for literature and included three studies that compared the outcome of hip arthroscopy between different BMI groups. We extracted and pooled the data. For continues data a weighted mean difference was calculated, for dichotomous variables a weighted odds ratio (OR) was calculated using Review Software Manager. Heterogeneity of the included studies was calculated using I(2) statistics. Data were extracted from two studies. In the Obese group, there was significant more conversion to total hip replacement or resurfacing hip replacement (OR = 2.21, 95% CI 1.07-4.56) and more re-arthroscopy (OR = 4.68, 95% CI 1.41-15.45). Any reoperation occurred more often in the obese group (OR = 2.87, 95% CI 1.53-5.38). In the Non Arthritic Hip Score obese scored lower than the non-Obese group [10.9 (-14,6 to 7.1)]. For the modified Harris Hip Score the score is - 6,6, according to the MCID this difference is clinically relevant. For both scores obese show lower outcomes but similar improvement after hip arthroscopy. Regarding a higher chance of needing a re-operation and lower subjective outcome scores obesity appears to have a negative influence on the outcome of hip arthroscopy.

Pyrenean ptarmigans decline under climatic and human influences through the Holocene.

In Europe, the Quaternary is characterized by climatic fluctuations known to have led to many cycles of contraction and expansion of species geographical ranges. In addition, during the Holocene, historical changes in human occupation such as colonization or abandonment of traditional land uses can also affect habitats. These climatically or anthropically induced geographic range changes are expected to produce considerable effective population size change, measurable in terms of genetic diversity and organization. The rock ptarmigan (Lagopus muta) is a small-bodied grouse occurring throughout Northern hemispheric arctic and alpine tundra. This species is not considered threatened at a continental scale, but the populations in the Pyrenees are of concern because of their small population size, geographical isolation and low genetic diversity. Here, we used 11 microsatellites to investigate genetic variations and differentiations and infer the overall demographic history of Pyrenean rock ptarmigan populations. The low genetic variability found in these populations has been previously thought to be the result of a bottleneck that occurred following the last glacial maximum (i.e., 10,000 years ago) or more recently (i.e., during the last 200 years). Our results clearly indicate a major bottleneck affecting the populations in the last tenth of the Holocene. We discuss how this decline can be explained by a combination of unfavorable and successive events that increased the degree of habitat fragmentation.

Transferability of microsatellite markers among economically and ecologically important galliform birds.

We used the partially sequenced genomes of the turkey and chicken to find a large number of microsatellite markers. We then characterized 10 polymorphic microsatellite markers developed by cross-species amplification from economically and ecologically important birds to various European sub-species of the grey partridge. Even though we used cross-species amplification, a high degree of polymorphism was conserved in all microsatellite markers. Cross-species amplification from birds of economic and ecological interest, such as chicken and turkey, could be an attractive approach to develop microsatellite markers and to use these to manage wild and captive populations of other galliforms, such as the grey partridge.

Effect of saquinavir/ritonavir on P-glycoprotein activity in healthy volunteers using digoxin as a probe.

BACKGROUND: Saquinavir and ritonavir, both human immunodeficiency virus-1 protease inhibitors, also inhibit the adenosine triphosphate-dependent efflux pump P-glycoprotein (P-gp), which is located at a variety of anatomic sites, including the human intestine. P-gp plays an important role in the absorption, distribution and elimination of numerous drugs. This study investigated the inhibitory potential of multiple administrations of ritonavir-boosted saquinavir at the target therapeutic dose of 1,000 mg saquinavir/100 mg ritonavir twice daily on the pharmacokinetics of oral digoxin, a model P-gp substrate that is predominantly excreted as unchanged drug in the urine. METHODS: In an open-label, 1-sequence, 2-period crossover study, a single digoxin dose of 0.5 mg was administered orally on Day 1. From Days 11 through 26, participants received oral administration of saquinavir/ritonavir 1,000/100 mg twice daily. A second dose of digoxin was administered on Day 24. Blood and urine sampling for pharmacokinetic analyses of digoxin was performed at scheduled time points on Days 1 - 4 and Days 24 - 27. Serial blood samples were drawn to determine plasma levels of saquinavir and ritonavir on Days 21 - 24. Adverse event reports were collected. RESULTS: Of the 17 enrolled participants (9 males and 8 females) who received at least one dose of study medication, 16 completed the study. Two weeks of pretreatment with ritonavir and saquinavir resulted in a 1.27-fold increase in digoxin Cmax (90% confidence interval (1.05 - 1.54)) and a 1.49-fold increase in AUC0-72 (90% CI (1.32 - 1.69)). Renal clearance decreased by a factor 0.88 from 111 to 97.3 ml/min while digoxin half-life increased from 37.0 to 45.3 h. The unbound fraction of digoxin was almost unaffected. The changes in digoxin renal clearance and exposure (AUC0-72) following 2 weeks of treatment with saquinavir/ritonavir were found to be more pronounced among female participants compared with males. Plasma concentrations of saquinavir/ritonavir at trough and at 4 h postdose were within the expected ranges for each gender, with female participants showing higher concentrations than male participants. All three treatments were well tolerated, with no serious adverse events noted. Despite the higher digoxin exposure among females compared to males following saquinavir/ritonavir administration, overall safety profiles were similar. On electrocardiographic readings, a trend of a longer PR interval was noted with triple combination of agents. CONCLUSIONS: Pretreatment with saquinavir/ritonavir 1,000/100 mg twice daily increased digoxin exposure most likely via P-gp-inhibition. Given the relatively narrow therapeutic window of digoxin, caution should be exercised when these three drugs are administered together. It is recommended to reduce digoxin doses and to monitor digoxin serum concentrations.

Cross-species amplification tests and diversity analysis using 56 PCR markers in Dactylis glomerata and Lolium perenne.

We report results of cross-species amplification in Dactylis glomerata and Lolium perenne of 12 simple sequence repeats (SSRs) isolated from Lolium multiflorum×Festuca glaucescens, 42 SSRs from Festuca arundinacea and two sequence tagged sites from Oryza sativa. We compared the transferability and diversity between D. glomerata and L. perenne, which are important forage crops. While Nei's gene diversity values were equivalent in both species (from 0.14 to 0.92), the mean number of allele per locus was more important in D. glomerata than in L. perenne (5.45 vs. 4.50). These markers will be used for analysing population structure in grassland populations under agronomic practices.

[Retinopathy of prematurity in Denmark 1974-1991. Analysis of the data from the Danish Registry of Diseases]. / Praematuritetsretinopati i Danmark 1974-1991. En analyse fra Det Danske Synsregister.

This study deals with registered Danish children with visual handicap due to retinopathy of prematurity (ROP) born between 1974 and 1991. There are 141 such children, corresponding to a frequency of 13.1 per 100.000 liveborn. The data was analysed for trends in time by chronologically subdividing the material into thirds, each group comprising 47 subjects. Birth weight and gestational age showed a decline over the period, median values in the three groups in chronological order being respectively 1.250 g, 1.100 g, and 960 g and 30, 28, and 27 weeks. Associated CNS handicaps were recorded in 17, 38, and 34%. Visual impairment was severe in all groups, the median corrected acuity of the better eye being below 1/60. Geographically there was a significant shift from an even distribution nationwide towards there being a preponderance of severe ROP cases in the Copenhagen area.

Retinopathy of prematurity 1974-91. An analysis of the Danish Register for the Visually Impaired.

Registration of visual impairment is compulsory in Denmark for the age group 0-17 years. With birth years 1974-91 141 subjects were in the register with retinopathy of prematurity as basic disease, giving a frequency of 13.1 per 100 000 liveborn. Compared with other countries this is a high figure, and the trend over the period is a slight annual increase. Further analysing the data for trends in time the material was subdivided chronologically into thirds, each group comprising 47 subjects. Birth weight and gestational age showed a decline: median values in the three groups were 1250, 1100, and 960 g, and 30, 28, and 27 weeks, respectively. Associated CNS handicaps were recorded in 17, 38, and 34%. Visual impairment was serious in all groups, the median corrected acuity of the better eye being below 1/60. Geographically there was a striking shift towards a Copenhagen area preponderance of heavy ROP cases, with one of the two NICUs to account for the main part of registered cases in the most recent period.