Bilateral iatrogenic [corrected] maxillary fractures after dental treatment in two aged horses

This clinical report describes two horses with bilateral maxillary fractures following dental treatment. The fractures occurred during dental treatment by a veterinarian, and both had rostral, transverse, and complete bilateral maxillary fractures with instability and minimal displacement. The fractures were repaired using bilateral intraoral wiring with the patients under general anesthesia. The postoperative period was without complications and the fractures healed as expected. Maxillary fractures during or after routine dental treatment are rare, but can occur, especially in older horses. Appropriate sedation and, if necessary, regional nerve blocks might reduce the risk of iatrogenic fractures of the maxilla. General anesthesia must be considered for tooth extraction in horses that are difficult to restrain.

Introgression in peripheral populations and colonization shape the genetic structure of the coastal shrub Armeria pungens

The coastal shrub Armeria pungens has a disjunct Atlantic-Mediterranean distribution. The historic range expansion underlying this distribution was investigated using the nuclear internal transcribed spacer region, three plastid regions (namely trnL-F, trnS-fM and matK) and morphometric data. A highly diverse ancestral lineage was identified in southwest Portugal. More recently, two areas have been colonized: (1) Corsica and Sardinia, where disjunct Mediterranean populations have been established as a result of the long-distance dispersal of Portuguese genotypes, and (2) the southern part of the Atlantic range, Gulf of Cadiz, where a distinct lineage showing no genetic differentiation among populations occurs. Genetic consequences of colonization seem to have been more severe in the Gulf of Cadiz than in Corsica-Sardinia. Although significant genetic divergence is associated with low plastid diversity in the Gulf of Cadiz, in Corsica-Sardinia, the loss of plastid haplotypes was not accompanied by divergence from disjunct Portuguese source populations. In addition, in its northernmost and southernmost populations, A. pungens exhibited evidence for ancient or ongoing introgression from sympatric congeners. Introgression might have created novel genotypes able to expand beyond the latitudinal margins of the species or, alternatively, these genotypes may be the result of surfing of alleles from other species in demographic equilibrium into peripheral populations of A. pungens. Our results highlight the evolutionary significance of genetic drift following the colonization of new areas and the key role of introgression in range expansion.

Endoscopic scoring of the tracheal septum in horses and its clinical relevance for the evaluation of lower airway health in horses

REASONS FOR PERFORMING STUDY

Although endoscopic scoring of the tracheal septum thickness is used as a diagnostic tool for evaluation of lower airway disease, its clinical relevance and reliability have never been critically assessed in the horse.

OBJECTIVES

To investigate if septum thickness scores (STS) are reliable and serve as a clinically useful indicator of lower airway disease status and/or inflammation.

METHODS

The variance of STS attributable to the horse, observer and changes over time was determined. The distribution of STS in a population of clinically normal horses and correlations of STS with age, gender, as well as mucus accumulation and cell differentials of tracheobronchial secretions and bronchoalveolar lavage fluid were investigated. Effects of altered pulmonary ventilation, induced by different drugs, on STS were assessed. Finally, STS of horses affected with recurrent airway obstruction (RAO) were compared to those of clinically normal horses.

RESULTS

Recorded STS showed excellent intra- and satisfactory interobserver agreement Established clinical, endoscopic and cytological measures of lower airway inflammation, i.e. mucus accumulation scores and airway neutrophilia, did not correlate with STS. In horses age > or = 10 years, septum scores were significantly higher (P = 0.022) than in younger horses. Septum thickness scores did not differ significantly between clinically normal and RAO-affected horses both in exacerbation and in remission. Horses with markedly increased breathing effort (i.e. with metacholine- or lobeline hydrochloride-challenge), often differed markedly (up to 1.9 scores), but the average of end-inspiratory and end-expiratory STS did not differ from baseline STS.

CONCLUSIONS AND CLINICAL RELEVANCE

Endoscopic STS are a reproducible measure, but STS did not correlate with clinical, endoscopic and cytological findings indicative of RAO or inflammatory airway disease.

Comparison of infectious complications during induction/consolidation chemotherapy versus allogeneic hematopoietic stem cell transplantation

Induction/consolidation chemotherapy and allogeneic hematopoietic stem cell transplantation (HSCT) for hematological malignancies are associated with treatment-related risks such as infections. The predominant types of infections are blood stream infections (BSIs) and respiratory tract infections. We prospectively compared infectious complications after induction/consolidation chemotherapy versus allogeneic HSCT in a directly comparable setting with both groups being hospitalized on the same ward. From July 2003 until June 2008, 492 hospitalizations of 321 patients took place; 237 chemotherapies and 255 HSCTs were performed. We observed 49 (20.7%) BSIs, 70 (29.5%) pneumonias and 11 (4.6%) probable or proven invasive mould infections in the chemotherapy group. In the HSCT group we detected 70 (27.5%) BSIs, 71 (27.8%) pneumonias and 14 (5.4%) probable or proven invasive mould infections. There was a trend toward more transfers to the intensive care unit (OR 1.61; 95%CI 0.95-2.72; P=0.074) and BSIs (OR 1.45; 95%CI 0.95-2.22; P=0.079) after HSCT; 44 (13.7%) patients died. In-hospital mortality was significantly higher in the HSCT group (OR 2.39; 95%CI 1.22-4.68; P=0.010). We conclude that the risk of pneumonia and invasive mould infection is comparable after induction/consolidation chemotherapy and allogeneic HSCT. However, there was a trend for more BSIs and intensive care unit stays and a higher mortality in the latter.

Phylogeography and host race differentiation in the European mistletoe (Viscum album L.)

Mistletoes are bird dispersed, hemi-parasitic shrubs infecting a large number of woody host plants. Chloroplast fragment length polymorphisms were used to study genetic differentiation among presumed host races, population genetic structure, and to elucidate the postglacial migration history of mistletoe (Viscum album) across the entire natural distribution range in Europe. The populations sampled belong to four closely related taxa, three of which are widely distributed and differ in their host trees, whereas a fourth taxon is rare and endemic to the Island of Crete. The molecular analysis of chloroplast DNA variation supported the distinction of these four taxa. We further found evidence for phylogeographical structure in each of the three widely distributed host races. Independent of host race, mistletoe haplotypes from Turkey were distinct and distant from those found elsewhere in Europe, suggesting that highly differentiated populations, and possibly new taxa, exist at the range limit of the species.

Silene as a model system in ecology and evolution

The genus Silene, studied by Darwin, Mendel and other early scientists, is re-emerging as a system for studying interrelated questions in ecology, evolution and developmental biology. These questions include sex chromosome evolution, epigenetic control of sex expression, genomic conflict and speciation. Its well-studied interactions with the pathogen Microbotryum has made Silene a model for the evolution and dynamics of disease in natural systems, and its interactions with herbivores have increased our understanding of multi-trophic ecological processes and the evolution of invasiveness. Molecular tools are now providing new approaches to many of these classical yet unresolved problems, and new progress is being made through combining phylogenetic, genomic and molecular evolutionary studies with ecological and phenotypic data.

Efficient molecular sexing in dioecious Silene latifolia and S. dioica and paternity analysis in F(1) hybrids

Two polymerase chain reaction-based assays have been developed that work in combination with an efficient DNA extraction protocol to rapidly and reliably determine sex in the dioecious plant species Silene latifolia and S. dioica. In addition, one of the assays allows assessing paternity in the F(1) generation of intra- and interspecific matings involving the two species.

A population genomic analysis of species boundaries: neutral processes, adaptive divergence and introgression between two hybridizing plant species

Little is known about the nature of species boundaries between closely related plant species and about the extent of introgression as a consequence of hybridization upon secondary contact. To address these topics we analyzed genome-wide differentiation between two closely related Silene species, Silene latifolia and S. dioica, and assessed the strength of introgression in sympatry. More than 300 AFLP markers were genotyped in three allopatric and three sympatric populations of each species. Outlier analyses were performed separately for sympatric and allopatric populations. Both positive and negative outlier loci were found, indicating that divergent and balancing selection, respectively, have shaped patterns of divergence between the two species. Sympatric populations of the two species were found to be less differentiated genetically than allopatric populations, indicating that hybridization has led to gene introgression. We conclude that differentiation between S. latifolia and S. dioica has been shaped by a combination of introgression and selection. These results challenge the view that species differentiation is a genome-wide phenomenon, and instead support the idea that genomes can be porous and that species differentiation has a genic basis.

Genetic structure of hybrid zones between Silene latifolia and Silene dioica (Caryophyllaceae): evidence for introgressive hybridization

Natural hybrid zones provide a valuable tool to study introgressive hybridization, because they can contain a wide variety of genotypes that result from many generations of recombination. Here we used molecular markers and morphological variation to describe the structure of two natural hybrid zones between Silene latifolia and Silene dioica in the Swiss Alps. Populations in both hybrid zones consisted of few intermediate hybrids and were dominated by backcross hybrids. The latter were also found in the parental populations at the margins of the hybrid zones. Out of 209 amplified fragment length polymorphism (AFLP) markers scored in 390 individuals, only 7 (3.3%) were species specific. These results indicate that introgression between S. dioica and S. latifolia is extensive, and that hybrid zones act as bridges to gene flow between these two species. Analysis of linkage disequilibrium identified few populations in which hybridization is ongoing, whereas in most populations linkage disequilibrium has eroded. Where hybridization is ongoing, strong changes in species-specific marker frequencies and morphological traits were observed. Plastid introgression into the hybrid zone was found to be bidirectional, but only the S. latifolia plastid haplotype was found in a nuclear S. dioica background. This unidirectional plastid introgression from S. latifolia into S. dioica is most likely due to pollen-flow from S. dioica onto S. latifolia, and results in plastid capture. Comparisons between the molecular and the morphological hybrid indices revealed that morphology in this study system is useful for identifying hybrids, but not for detailed analysis of hybrid zone structure.

Legionella bozemanii, an elusive agent of fatal cavitary pneumonia

A 67-year-old patient died of Legionella bozemanii pneumonia with negative urinary antigen and negative serology. Cystic lesions in pneumonia of unknown origin should lead to the differential diagnosis of L. bozemanii infections.

Optimierung der chirurgischen Händedesinfektion

For more than 110 years hands of surgeons have been treated before a surgical procedure in order to reduce the bacterial density. The kind and duration of treatment, however, has changed significantly over time. Recent scientific evidence suggests a few changes with the aim to optimize both the efficacy and the dermal tolerance. Aim of this article is the presentation and discussion of new insights in surgical hand disinfection. A hand wash should be performed before the first disinfection of a day, ideally at least 10 min before the beginning of the disinfection as it has been shown that a 1 min hand wash significantly increases skin hydration for up to 10 min. The application time may be as short as 1.5 min depending on the type of hand rub. Hands and forearms should be kept wet with the hand rub for the recommended application time in any case. A specific rub-in procedure according to EN 12791 has been found to be suitable in order to avoid untreated skin areas. The alcohol-based hand rub should have a proven excellent dermal tolerance in order to ensure appropriate compliance. Considering these elements in clinical practice can have a significant impact to optimize the high quality of surgical hand disinfection for prevention of surgical site infections.