Successful embolization of a clinically significant pulmonary arteriovenous malformation

The authors present the clinical case of a 59-year-old female patient with a history of peripheral desaturation, which was detected in the perioperative period 4 years earlier. She reported exertional dyspnea, quantified as grade 2 on the Modified Medical Research Council (mMRC) Dyspnea Scale (walks slower than people of the same age because of dyspnea or has to stop for breath when walking at her own pace), and morning cough with mucoid sputum and denied platypnea, epistaxis, telangiectasias and hemoptysis. A computed chest tomography scan revealed a contrast-enhanced lesion on the right upper lobe with an afferent and two efferent vessels compatible with pulmonary arteriovenous malformation. The transesophageal echocardiogram revealed an important right-left shunt compatible with arteriovenous fistula in the pulmonary circulation. An angiography confirmed the diagnosis and a selective embolization of the afferent artery was performed with resolution of symptoms.

Temperature and microclimate refugia use influence migratory timings of a threatened grassland bird

BACKGROUND

Seasonal changes in resource availability are known to influence the migratory behaviour of animals, including both timing and distance. While the influence of environmental cues on migratory behaviour has been widely studied at the population level, it has rarely been examined at the spatial scale at which individuals experience their environment. Here, we test the hypothesis that individuals exposed to similar large-scale environmental cues may vary in migratory behaviour in response to the different microclimate conditions they experience at fine scales.

METHODS

We combine high-spatial and temporal resolution microclimate and habitat information with GPS tracking data for a partially migratory threatened grassland bird. Data from 47 little bustards (Tetrax tetrax; 67 breeding events) tracked between 2009 and 2019 was used to (i) evaluate individual consistency in migratory behaviour (timing and distance) and (ii) assess whether the local environmental characteristics experienced by individuals - and in particular their use of microclimate refugia - influence distance and timing of migration, from and to the breeding sites.

RESULTS

Migratory distance was consistent for birds tracked over multiple years, while the timing of migration showed high variability among individuals. Departures from breeding areas spanned from May to August, with a few birds remaining in their breeding areas. Vegetation greenness (a proxy for food availability) was positively associated with the time birds spent in the breeding area. The best model also included a positive effect of microclimate refugia availability on breeding season length, although an interaction with temperature suggested that this effect did not occur at the highest relative temperatures. The return date to breeding grounds, although spanning from September to April, was not influenced by the environmental conditions or food availability.

CONCLUSIONS

Food availability, measured by a vegetation greenness proxy, was associated with later migration at the end of the breeding season. Availability of cooler microclimate refugia may also allow for later departures from the breeding sites in all but the hottest conditions. Management measures that increase microclimate refugia availability and provide foraging resources can thus potentially increase the length of the breeding season for this species.

Combining bird tracking data with high-resolution thermal mapping to identify microclimate refugia

Elevated temperatures can have a range of fitness impacts, including high metabolic cost of thermoregulation, hence access to microclimate refugia may buffer individuals against exposure to high temperatures. However, studies examining the use of microclimate refugia, remain scarce. We combined high resolution microclimate modelling with GPS tracking data as a novel approach to identify the use and availability of cooler microclimate refugia (sites > 0.5 °C cooler than the surrounding landscape) at the scales experienced by individual animals. 77 little bustards (Tetrax tetrax) were tracked between 2009 and 2019. The 92,685 GPS locations obtained and their surrounding 500 m areas were characterised with hourly temperature and habitat information at 30 m × 30 m and used to determine microclimate refugia availability and use. We found that the semi-natural grassland landscapes used by little bustards have limited availability of cooler microclimate areas-fewer than 30% of the locations. The use of cooler microclimate sites by little bustards increased at higher ambient temperatures, suggesting that individuals actively utilise microclimate refugia in extreme heat conditions. Microclimate refugia availability and use were greater in areas with heterogeneous vegetation cover, and in coastal areas. This study identified the landscape characteristics that provide microclimate opportunities and shelter from extreme heat conditions. Little bustards made greater use of microclimate refugia with increasing temperatures, particularly during the breeding season, when individuals are highly site faithful. This information can help identify areas where populations might be particularly exposed to climate extremes due to a lack of microclimate refugia, and which habitat management measures may buffer populations from expected increased exposure to temperature extremes.

Cerebral Air Embolism: A Case of a Rare Transthoracic Needle Biopsy Complication

Transthoracic needle biopsy (TNB) is a fundamental procedure in the diagnosis of a wide spectrum of thoracic diseases replacing more invasive surgical procedures. The procedure may be performed with computed tomography (CT) or ultrasound imaging guidance, with CT being the more commonly utilized. Although less invasive than surgery, there is still a complication risk associated with this procedure. These can be local such as pneumothorax, parenchymal hemorrhage, tumor seeding, and hemoptysis, or systemic such as air embolism. The authors report a case of cerebral circulation air embolism as a complication of TNB in a 54-year-old male with suspected lung tumor followed by a brief review of the current literature.

Histologic Features of Colon Biopsies (Geboes Score) Associated With Progression of Ulcerative Colitis for the First 36 Months After Biopsy

BACKGROUND & AIMS

In addition to findings from endoscopy, histologic features of colon biopsies have been associated with outcomes of patients with ulcerative colitis (UC). We investigated associations between Geboes scores (a system to quantify structural changes and inflammatory activity in colon biopsies) and UC progression, and the time period over which this association is valid.

METHODS

We analyzed data from 399 asymptomatic patients with UC enrolled in the ACERTIVE study, followed at 13 inflammatory bowel disease (IBD) centers in Portugal through 31 December 2019. Blood and stool samples were collected and analyzed, and all patients underwent sigmoidoscopy within 24 h of sample collection. We assessed baseline endoscopic status (Mayo endoscopic subscore), histologic features of 2 sigmoid and 2 rectal biopsies (Geboes score), and concentration of fecal calprotectin (FC). The primary outcome was UC progression (surgical, pharmacologic, and clinical events). We generated survival curves for 36 months or less and more than 36 months after biopsy according to Geboes score using the Kaplan-Meier method and compared findings with those from a log rank test. Cox regression was adjusted for Mayo endoscopic subscore, Geboes score, and level of FC; results were expressed as adjusted hazard ratios (HR) with 95% CIs.

RESULTS

Patients with Geboes scores >2B.0, Geboes scores >3.0, or Geboes scores >4.0 had a higher frequency of, and a shorter time to UC progression, than patients with Geboes scores ≤2B.0, Geboes scores ≤3.0, or Geboes score ≤4.0 (P < .001). Disease progression occurred earlier in patients with Geboes scores >2B.0, Geboes scores >3.0, or Geboes scores >4.0 compared with patients with Geboes scores ≤2B.0 (HR, 2.021; 95% CI, 1.158-3.526), Geboes scores ≤3.0 (HR, 2.007; 95% CI, 1.139-3.534), or Geboes scores ≤4.0 (HR, 2.349; 95% CI, 1.269-4.349), respectively, in the first 36 months after biopsy. Similar results were found for patients with concentrations of FC below 150 μg/g.

CONCLUSIONS

We found histologic features of colon biopsies (Geboes score) to be an independent risk factor for progression of UC in the first 36 months after biopsy.

A new bipartite begomovirus naturally infecting Pyrenacantha sp. in Mozambique

A begomovirus was isolated from a Pyrenacantha sp. plant with yellow mosaic symptoms collected in a maize production field in Mozambique. The complete DNA-A and DNA-B components have a genomic organization typical of Old World, bipartite begomoviruses. Based on the current ICTV species demarcation criteria for the genus Begomovirus, the virus isolate, named Pyrenacantha yellow mosaic virus (PyYMV), is a member of a new species, for which the name "Begomovirus pyrenacanthae" is proposed. Alignment of their common regions (CR) indicated a 35-nt insertion in the DNA-A CR. The nt sequence identity between the CRs is only 83% but increases to 96% when the 35-nt insertion is removed from the alignment. This is the first report of a begomovirus naturally infecting Pyrenacantha spp.

Synthetic Cannabinoids JWH-122 and THJ-2201 Disrupt Endocannabinoid-Regulated Mitochondrial Function and Activate Apoptotic Pathways as a Primary Mechanism of In Vitro Nephrotoxicity at In Vivo Relevant Concentrations

The widespread recreational use of synthetic cannabinoids (SCBs) represents a major public health issue, as reports of intoxications and deaths following SCB use rapidly mount up. Specifically, a direct link between SCB use and acute kidney injury (AKI) has been established, although the pathophysiologic mechanisms remain undefined. Here we assessed the in vitro nephrotoxicity of 3 commonly detected and structurally distinct SCBs-AB-FUBINACA, JWH-122, and THJ-2201-in human proximal tubule cells (HK-2), to ascertain potential similarities and/or differences regarding their nephrotoxicity signatures. We showed that 2 of the 3 SCBs tested, namely JWH-122 and THJ-2201, at in vivo relevant concentrations (1 nM-1 μM), triggered apoptotic cell death pathways, mainly through a shared mechanism involving the deregulation of mitochondrial function (ie, with mitochondrial membrane hyperpolarization and increased intracellular ATP levels), as the primary molecular signature of nephrotoxicity mechanism. Noteworthy, no SCB affected cell viability (MTT reduction, lactate dehydrogenase release, Neutral Red inclusion). Use of the cannabinoid receptor (CBR) antagonists SR141716A and SR144528, as well as HEK293T cells, which do not express CBRs, confirmed the involvement of these receptors in SCB-mediated mitochondrial membrane hyperpolarization but not on other events, suggesting an off-target action regulating SCB-induced kidney cell death. Our results further strengthen the relevance of the endocannabinoid system in maintaining mitochondrial function in kidney cells, as we demonstrate that HK-2 incubation with CBR antagonists or inhibitors of endocannabinoid biosynthesis (ie, methyl arachydonyl fluorophosphonate, tetrahydrolipstatin) alone produced deleterious effects similar to those now reported for SCBs. Overall, SCB-induced nephrotoxicity seems to be mainly regulated at the mitochondrial level, but the specific mechanisms involved require further clarification.

Extreme events are more likely to affect the breeding success of lesser kestrels than average climate change

Climate change is predicted to severely impact interactions between prey, predators and habitats. In Southern Europe, within the Mediterranean climate, herbaceous vegetation achieves its maximum growth in middle spring followed by a three-month dry summer, limiting prey availability for insectivorous birds. Lesser kestrels (Falco naumanni) breed in a time-window that matches the nestling-rearing period with the peak abundance of grasshoppers and forecasted climate change may impact reproductive success through changes in prey availability and abundance. We used Normalised Difference Vegetation Index (NDVI) as a surrogate of habitat quality and prey availability to investigate the impacts of forecasted climate change and extreme climatic events on lesser kestrel breeding performance. First, using 14 years of data from 15 colonies in Southwestern Iberia, we linked fledging success and climatic variables with NDVI, and secondly, based on these relationships and according to climatic scenarios for 2050 and 2070, forecasted NDVI and fledging success. Finally, we evaluated how fledging success was influenced by drought events since 2004. Despite predicting a decrease in vegetation greenness in lesser kestrel foraging areas during spring, we found no impacts of predicted gradual rise in temperature and decline in precipitation on their fledging success. Notwithstanding, we found a decrease of 12% in offspring survival associated with drought events, suggesting that a higher frequency of droughts might, in the future, jeopardize the recent recovery of the European population. Here, we show that extreme events, such as droughts, can have more significant impacts on species than gradual climatic changes, especially in regions like the Mediterranean Basin, a biodiversity and climate change hotspot.

An improved protocol for efficient transformation and regeneration of Setaria italica

An efficient and improved transformation method for functional genetics studies in S. italica, being a boon for the Setaria scientific community and for crop improvement. Foxtail millet (Setaria italica) is a short life cycle C4 plant, with sequenced genome, and a potential model plant for C4 species. S. italica is also important on a global food security and healthiness context due to its importance in arid and semi-arid areas. However, despite its importance, there are just few transformation protocols directed to this species. The current protocols reached about 5.5-9% of efficiency, which do not make it a valuable model organism. Different types of explants were used in the above mentioned methods, such as immature and mature inflorescence and shoot apex. However, these techniques have many limitations, such as unavailability of explants throughout the year and a crucial, laborious and considerable time-consuming selection. Aiming a simplified and efficient methodology, we adopted dry mature seeds as explants, which are available in abundance, are constant along the year and well responsive to tissue culture, in addition to a differentiated approach that reaches on an average 19.2% transformation efficiency of S. italica. Thus, we propose a protocol that optimizes the transformation efficiency of this cereal crop allowing a high increase on transformation and regeneration rates. Our transformation protocol provides an interesting tool for Setaria community research as well as enables new strategies for breeding enhanced productivity in the species.

Wind turbines cause functional habitat loss for migratory soaring birds

Wind energy production has expanded to meet climate change mitigation goals, but negative impacts of wind turbines have been reported on wildlife. Soaring birds are among the most affected groups with alarming fatality rates by collision with wind turbines and an escalating occupation of their migratory corridors. These birds have been described as changing their flight trajectories to avoid wind turbines, but this behaviour may lead to functional habitat loss, as suitable soaring areas in the proximity of wind turbines will likely be underused. We modelled the displacement effect of wind turbines on black kites (Milvus migrans) tracked by GPS. We also evaluated the impact of this effect at the scale of the landscape by estimating how much suitable soaring area was lost to wind turbines. We used state-of-the-art tracking devices to monitor the movements of 130 black kites in an area populated by wind turbines, at the migratory bottleneck of the Strait of Gibraltar. Landscape use by birds was mapped from GPS data using dynamic Brownian bridge movement models, and generalized additive mixed modelling was used to estimate the effect of wind turbine proximity on bird use while accounting for orographic and thermal uplift availability. We found that areas up to approximately 674 m away from the turbines were less used than expected given their uplift potential. Within that distance threshold, bird use decreased with the proximity to wind turbines. We estimated that the footprint of wind turbines affected 3%-14% of the areas suitable for soaring in our study area. We present evidence that the impacts of wind energy industry on soaring birds are greater than previously acknowledged. In addition to the commonly reported fatalities, the avoidance of turbines by soaring birds causes habitat losses in their movement corridors. Authorities should recognize this further impact of wind energy production and establish new regulations that protect soaring habitat. We also showed that soaring habitat for birds can be modelled at a fine scale using publicly available data. Such an approach can be used to plan low-impact placement of turbines in new wind energy developments.

Global, regional, and national burden of Alzheimer's disease and other dementias, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND

The number of individuals living with dementia is increasing, negatively affecting families, communities, and health-care systems around the world. A successful response to these challenges requires an accurate understanding of the dementia disease burden. We aimed to present the first detailed analysis of the global prevalence, mortality, and overall burden of dementia as captured by the Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study 2016, and highlight the most important messages for clinicians and neurologists.

METHODS

GBD 2016 obtained data on dementia from vital registration systems, published scientific literature and surveys, and data from health-service encounters on deaths, excess mortality, prevalence, and incidence from 195 countries and territories from 1990 to 2016, through systematic review and additional data-seeking efforts. To correct for differences in cause of death coding across time and locations, we modelled mortality due to dementia using prevalence data and estimates of excess mortality derived from countries that were most likely to code deaths to dementia relative to prevalence. Data were analysed by standardised methods to estimate deaths, prevalence, years of life lost (YLLs), years of life lived with disability (YLDs), and disability-adjusted life-years (DALYs; computed as the sum of YLLs and YLDs), and the fractions of these metrics that were attributable to four risk factors that met GBD criteria for assessment (high body-mass index [BMI], high fasting plasma glucose, smoking, and a diet high in sugar-sweetened beverages).

FINDINGS

In 2016, the global number of individuals who lived with dementia was 43·8 million (95% uncertainty interval [UI] 37·8-51·0), increased from 20.2 million (17·4-23·5) in 1990. This increase of 117% (95% UI 114-121) contrasted with a minor increase in age-standardised prevalence of 1·7% (1·0-2·4), from 701 cases (95% UI 602-815) per 100 000 population in 1990 to 712 cases (614-828) per 100 000 population in 2016. More women than men had dementia in 2016 (27·0 million, 95% UI 23·3-31·4, vs 16.8 million, 14.4-19.6), and dementia was the fifth leading cause of death globally, accounting for 2·4 million (95% UI 2·1-2·8) deaths. Overall, 28·8 million (95% UI 24·5-34·0) DALYs were attributed to dementia; 6·4 million (95% UI 3·4-10·5) of these could be attributed to the modifiable GBD risk factors of high BMI, high fasting plasma glucose, smoking, and a high intake of sugar-sweetened beverages.

INTERPRETATION

The global number of people living with dementia more than doubled from 1990 to 2016, mainly due to increases in population ageing and growth. Although differences in coding for causes of death and the heterogeneity in case-ascertainment methods constitute major challenges to the estimation of the burden of dementia, future analyses should improve on the methods for the correction of these biases. Until breakthroughs are made in prevention or curative treatment, dementia will constitute an increasing challenge to health-care systems worldwide.

FUNDING

Bill & Melinda Gates Foundation.

Phenolic Imidazole Derivatives with Dual Antioxidant/Antifungal Activity: Synthesis and Structure-Activity Relationship

BACKGROUND

Previous publications show that the addition of a phenolic antioxidant to an antifungal agent, considerably enhances the antifungal activity.

OBJECTIVE

Synthesis of novel compounds combining phenolic units with linear or cyclic nitrogencontaining organic molecules with antioxidant/antifungal activity using methodologies previously developed in the group.

METHODS

Several N- [1,2-dicyano-2- (arylidenamino) vinyl]-O-alkylformamidoximes 3 were synthesized and cyclized to 4,5-dicyano-N- (N´-alcoxyformimidoyl)-2-arylimidazoles 4 upon reflux in DMF, in the presence of manganese dioxide or to 6-cyano-8-arylpurines 5 when the reagent was refluxed in acetonitrile with an excess of triethylamine. These compounds were tested for their antioxidant activity by cyclic voltammetry, DPPH radical (DPPH•) assay and deoxyribose degradation assay. The minimum inhibitory concentration (MIC) of all compounds was evaluated against two yeast species, Saccharomyces cerevisiae and Candida albicans, and against bacteria Bacillus subtilis (Gram-positive) and Escherichia coli (Gram negative). Their cytotoxicity was evaluated in fibroblasts.

RESULTS

Among the synthetised compounds, five presented higher antioxidant activity than reference antioxidant Trolox and from these compounds, four presented antifungal activity without toxic effects in fibroblasts and bacteria.

CONCLUSION

Four novel compounds presented dual antioxidant/antifungal activity at concentrations that are not toxic to bacteria and fibroblasts. The active molecules can be used as an inspiration for further studies in this area.

EU protected area network did not prevent a country wide population decline in a threatened grassland bird

Background

Few studies have assessed the effectiveness of the Protected Area networks on the conservation status of target species. Here, we assess the effectiveness of the Portuguese Natura 2000 (the European Union network of protected areas) in maintaining a species included in the Annex I of the Bird Directive, namely the population of a priority farmland bird, the little bustard Tetrax tetrax.

Methods

We measured the effectiveness of the Natura 2000 by comparing population trends across time (2003–2006 and 2016) in 51 areas, 21 of which within 12 Special Protection Areas (SPA) that were mostly designated for farmland bird conservation and another 30 areas without EU protection.

Results

Overall, the national population is estimated to have declined 49% over the last 10–14 years. This loss was found to be proportionally larger outside SPA (64% decline) compared to losses within SPA (25% decline). However, the absolute male density decline was significantly larger within SPA .

Discussion

In spite of holding higher population densities and having prevented habitat loss, we conclude that Natura 2000 was not effective in buffering against the overall bustard population decline. Results show that the mere designation of SPA in farmland is not enough to secure species populations and has to be combined with agricultural policies and investment to maintain not only habitat availability but also habitat quality.

Inhalation of Bacterial Cellulose Nanofibrils Triggers an Inflammatory Response and Changes Lung Tissue Morphology of Mice

In view of the growing industrial use of Bacterial cellulose (BC), and taking into account that it might become airborne and be inhaled after industrial processing, assessing its potential pulmonary toxic effects assumes high relevance. In this work, the murine model was used to assess the effects of exposure to respirable BC nanofibrils (nBC), obtained by disintegration of BC produced by Komagataeibacter hansenii. Murine bone marrow-derived macrophages (BMMΦ) were treated with different doses of nBC (0.02 and 0.2 mg/mL, respectively 1 and 10 μg of fibrils) in absence or presence of 0.2% Carboxymethyl Cellulose (nBCMC). Furthermore, mice were instilled intratracheally with nBC or nBCMC at different concentrations and at different time-points and analyzed up to 6 months after treatments. Microcrystaline Avicel-plus® CM 2159, a plant-derived cellulose, was used for comparison. Markers of cellular damage (lactate dehydrogenase release and total protein) and oxidative stress (hydrogen peroxidase, reduced glutathione, lipid peroxidation and glutathione peroxidase activity) as well presence of inflammatory cells were evaluated in brochoalveolar lavage (BAL) fluids. Histological analysis of lungs, heart and liver tissues was also performed. BAL analysis showed that exposure to nBCMC or CMC did not induce major alterations in the assessed markers of cell damage, oxidative stress or inflammatory cell numbers in BAL fluid over time, even following cumulative treatments. Avicel-plus® CM 2159 significantly increased LDH release, detected 3 months after 4 weekly administrations. However, histological results revealed a chronic inflammatory response and tissue alterations, being hypertrophy of pulmonary arteries (observed 3 months after nBCMC treatment) of particular concern. These histological alterations remained after 6 months in animals treated with nBC, possibly due to foreign body reaction and the organism’s inability to remove the fibers. Overall, despite being a safe and biocompatible biomaterial, BC-derived nanofibrils inhalation may lead to lung pathology and pose significant health risks.

Higgs EFT for 2HDM and beyond

We discuss the validity of the Standard Model Effective Field Theory (SM EFT) as the low-energy effective theory for the two-Higgs-doublet Model (2HDM). Using the up-to-date Higgs signal strength measurements at the LHC, one can obtain a likelihood function for the Wilson coefficients of dimension-6 operators in the EFT Lagrangian. Given the matching between the 2HDM and the EFT, the constraints on the Wilson coefficients can be translated into constraints on the parameters of the 2HDM Lagrangian. We discuss under which conditions such a procedure correctly reproduces the true limits on the 2HDM. Finally, we employ the SM EFT to identify the pattern of the Higgs boson couplings that are needed to improve the fit to the current Higgs data. To this end, one needs, simultaneously, to increase the top Yukawa coupling, decrease the bottom Yukawa coupling, and induce a new contact interaction of the Higgs boson with gluons. We comment on how these modifications can be realized in the 2HDM extended by new colored particles.

Delivery of LLKKK18 loaded into self-assembling hyaluronic acid nanogel for tuberculosis treatment

Tuberculosis (TB), a disease caused by the human pathogen Mycobacterium tuberculosis, recently joined HIV/AIDS on the top rank of deadliest infectious diseases. Low patient compliance due to the expensive, long-lasting and multi-drug standard therapies often results in treatment failure and emergence of multi-drug resistant strains. In this scope, antimicrobial peptides (AMPs) arise as promising candidates for TB treatment. Here we describe the ability of the exogenous AMP LLKKK18 to efficiently kill mycobacteria. The peptide's potential was boosted by loading into self-assembling Hyaluronic Acid (HA) nanogels. These provide increased stability, reduced cytotoxicity and degradability, while potentiating peptide targeting to main sites of infection. The nanogels were effectively internalized by macrophages and the peptide presence and co-localization with mycobacteria within host cells was confirmed. This resulted in a significant reduction of the mycobacterial load in macrophages infected in vitro with the opportunistic M. avium or the pathogenic M. tuberculosis, an effect accompanied by lowered pro-inflammatory cytokine levels (IL-6 and TNF-α). Remarkably, intra-tracheal administration of peptide-loaded nanogels significantly reduced infection levels in mice infected with M. avium or M. tuberculosis, after just 5 or 10 every other day administrations. Considering the reported low probability of resistance acquisition, these findings suggest a great potential of LLKKK18-loaded nanogels for TB therapeutics.

Antimicrobial peptides as novel anti-tuberculosis therapeutics

Tuberculosis (TB), a disease caused by the human pathogen Mycobacterium tuberculosis, has recently joined HIV/AIDS as the world's deadliest infectious disease, affecting around 9.6 million people worldwide in 2014. Of those, about 1.2 million died from the disease. Resistance acquisition to existing antibiotics, with the subsequent emergence of Multi-Drug Resistant mycobacteria strains, together with an increasing economic burden, has urged the development of new anti-TB drugs. In this scope, antimicrobial peptides (AMPs), which are small, cationic and amphipathic peptides that make part of the innate immune system, now arise as promising candidates for TB treatment. In this review, we analyze the potential of AMPs for this application. We address the mechanisms of action, advantages and disadvantages over conventional antibiotics and how problems associated with its use may be overcome to boost their therapeutic potential. Additionally, we address the challenges of translational development from benchside to bedside, evaluate the current development pipeline and analyze the expected global impact from a socio-economic standpoint. The quest for more efficient and more compliant anti-TB drugs, associated with the great therapeutic potential of emerging AMPs and the rising peptide market, provide an optimal environment for the emergence of AMPs as promising therapies. Still, their pharmacological properties need to be enhanced and manufacturing-associated issues need to be addressed.

Laccase immobilization on bacterial nanocellulose membranes: Antimicrobial, kinetic and stability properties

This work studied the physical immobilization of a commercial laccase on bacterial nanocellulose (BNC) aiming to identify the laccase antibacterial properties suitable for wound dressings. Physico-chemical analysis demonstrates that the BNC structure is manly formed by pure crystalline Iα cellulose. The pH optimum and activation energy of free laccase depends on the substrate employed corresponding to pH 6, 7, 3 and 57, 22, 48kJmol(-1) for 2,6-dimethylphenol (DMP), catechol and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), respectively. The Michaelis-Menten constant (Km) value for the immobilized laccase (0.77mM) was found to be almost double of that of the free enzyme (0.42mM). However, the specific activities of immobilized and free laccase are similar suggesting that the cage-like structure of BNC allows entrapped laccase to maintain some flexibility and favour substrate accessibility. The results clearly show the antimicrobial effect of laccase in Gram-positive (92%) and Gram-negative (26%) bacteria and cytotoxicity acceptable for wound dressing applications.

Improved burn wound healing by the antimicrobial peptide LLKKK18 released from conjugates with dextrin embedded in a carbopol gel

Antimicrobial peptides (AMPs) are good candidates to treat burn wounds, a major cause of morbidity, impaired life quality and resources consumption in developed countries. We took advantage of a commercially available hydrogel, Carbopol®, a vehicle for topical administration that maintains a moist environment within the wound site. We hypothesized that the incorporation of LLKKK18 conjugated to dextrin would improve the healing process in rat burns. Whereas the hydrogel improves healing, LLKKK18 released from the dextrin conjugates further accelerated wound closure, and simultaneously improving the quality of healing. Indeed, the release of LLKKK18 reduced oxidative stress and inflammation (low neutrophil and macrophage infiltration and pro-inflammatory cytokines levels). Importantly, it induced a faster resolution of the inflammatory stage through early M2 macrophage recruitment. In addition, LLKKK18 stimulated angiogenesis (increased VEGF and microvessel development in vivo). Moreover, collagen staining evaluated by Masson's Trichrome was visually much more intense after treatment with LLKKK18, suggesting higher collagen deposition. Overall, we generated an effective, safe and inexpensive formulation that maintains a moist environment in the wound, easy to apply and remove, and with potential to prevent infection due to the presence of an antimicrobial peptide. These findings propel us to further study this LLKKK18-containing formulation, setting the foundations towards a potential therapeutic approach for burn wound treatment.

STATEMENT OF SIGNIFICANCE

This work presents a newly developed formulation that holds great potential as a therapeutic approach for burn treatment. It is based on the sustained delivery of an antimicrobial peptide - LLKKK18 - from conjugates with dextrin, after degradation of dextrin backbone upon exposure to wound α-amylases. Conjugates were further embedded in Carbopol®, a commercially available hydrogel, suitable for topical administration and that provides a moist environment to the wound. Overall, we obtained an efficient, safe and non-expensive formulation that improves burn wound healing, maintains a moist environment within the wound, is easy to apply-and-remove, and has potential to prevent infection due to the presence of an antimicrobial peptide. Importantly, this is the first time the wound healing ability of LLKKK18 is demonstrated and that its main mechanisms of action are identified.

Mosaic-level inference of the impact of land cover changes in agricultural landscapes on biodiversity: a case-study with a threatened grassland bird

Changes in land use/land cover are a major driver of biodiversity change in the Mediterranean region. Understanding how animal populations respond to these landscape changes often requires using landscape mosaics as the unit of investigation, but few previous studies have measured both response and explanatory variables at the land mosaic level. Here, we used a “whole-landscape” approach to assess the influence of regional variation in the land cover composition of 81 farmland mosaics (mean area of 2900 ha) on the population density of a threatened bird, the little bustard (Tetrax tetrax), in southern Portugal. Results showed that ca. 50% of the regional variability in the density of little bustards could be explained by three variables summarising the land cover composition and diversity in the studied mosaics. Little bustard breeding males attained higher population density in land mosaics with a low land cover diversity, with less forests, and dominated by grasslands. Land mosaic composition gradients showed that agricultural intensification was not reflected in a loss of land cover diversity, as in many other regions of Europe. On the contrary, it led to the introduction of new land cover types in homogenous farmland, which increased land cover diversity but reduced overall landscape suitability for the species. Based on these results, the impact of recent land cover changes in Europe on the little bustard populations is evaluated.

Adenoma incidence decreases under the effect of polypectomy

AIM: To investigate whether, under the influence of polypectomy, the incidence of adenoma decreases with age.

METHODS: Consecutive patients with colonic adenomas identified at index colonoscopy were retrospectively selected if they had undergone three or more complete colonoscopies, at least 24 mo apart. Patients who had any first-degree relative with colorectal cancer were excluded. Data regarding number of adenomas at each colonoscopy, their location, size and histological classification were recorded. The monthly incidence density of adenomas after the index examination was estimated for the study population, by using the person-years method. Baseline adenomas were excluded from incidence calculations but their characteristics were correlated with recurrence at follow-up, using the χ² test.

RESULTS: One hundred and fifty-six patients were included (109 male, mean age at index colonoscopy 56.8 ± 10.3 years), with follow-up that ranged from 48 to 232 mo. No significant correlations were observed between the number, the presence of villous component, or the size of adenomas at index colonoscopy and the presence of adenomas at subsequent colonoscopies (P = 0.49, 0.12 and 0.78, respectively). The incidence of colonic adenomas was observed to decay from 1.4% person-months at the beginning of the study to values close to 0%, at 12 years after index colonoscopy.

CONCLUSION: Our results suggest the sporadic formation of adenomas occurs within a discrete period and that, when these adenomas are removed, all neoplasia-prone clones may be extinguished.

Physical therapy intervention (PTI) increases plasma brain-derived neurotrophic factor (BDNF) levels in non-frail and pre-frail elderly women

Biomarkers are important factors in the identification of the frail elderly (higher risk of developing disease) and in assessing the impact of PTI. On the other hand, BDNF has been related to neuroprotection in a series of central nervous system diseases in older age. The levels of BDNF in groups of elderly women classified according to Fried phenotype (non-frail and pre-frail) were compared. We assessed the impact of a PTI on BDNF levels. A convenience sample of 48 elderly women was randomly selected. The PTI group was composed by 20 elderly women selected from this group. Plasma neurotrophic factors, such as BDNF, glial-derived neutrophic factor (GDNF), and nerve growth factor (NGF) were measured by enzyme-linked immunosorbent assay (ELISA). Timed-up-and-go (TUG) test, hand-grip and work/body weight were evaluated before and after the intervention. Plasma concentrations of BDNF were significantly higher in non-frail in comparison to pre-frail elderly women. After the PTI, higher levels of BDNF were found in elderly women (before 351±68 pg/ml and after 593±79 pg/ml; p<0.001). Both groups had an increase in BDNF levels after the PTI. The low levels of BDNF in pre-frail elderly women suggest that this neurotrophic factor may be a key pathophysiological mediator in the syndrome of frailty. The fact that PTI increased BDNF levels in both groups suggests that it may be possible to modify this phenotype.

Di(hetero)arylamines in the benzo[b]thiophene series as novel potent antioxidants

The damaging consequences of oxidative stress are known to be involved in several pathologies. So, the development of new drugs that can aid cells to cope with excessive levels of free radicals still assumes great relevance. Here, we investigated the antioxidant properties of four novel di(hetero)arylamines (named MJQ1, MJQ3, MJQ4 and MJQ5), sharing a common benzo[b]thiophene nucleus (an indole analogue), against oxidative damage induced to H9c2 myoblasts. Cell proliferation, evaluated by the sulforhodamine B assay, was not compromised by the presence of any of these compounds for concentrations below 50 μM (at 24 h) and 1 μM (72 h). Moreover, all of them showed a dose-dependent protective effect against tert-butylhydroperoxide (t-BHP)-induced cell death for concentrations in the nanomolar range. Their ability to scavenge free radicals seems to account for their protective effects, as they were able to prevent almost completely, at 25 nM, t-BHP-induced intracellular ROS formation, assessed by DCF fluorescence. Furthermore, their relatively high partition coefficient values are indicative of their ability to easily permeate lipid membranes and act intracellularly. Additionally, these novel diarylamines led to a reduction, between 60-70%, of the amount of DNA strand breaks induced by t-BHP, evaluated by the Comet assay, and lipid peroxidation (TBARS assay) induced by the oxidant pair ascorbate/iron. In all these parameters, which show their ability to prevent the oxidation of the main biomolecules, their protective role was superior to the traditional antioxidant Trolox. Although the mechanisms underlying the action of these diarylamines are currently under investigation, the data obtained so far reveals their high pharmacological potential as antioxidant molecules.

Free radicals in the regulation of damage and cell death - basic mechanisms and prevention

Reactive oxygen (ROS) and nitrogen (RNS) species are known to accumulate intracellularly due to both exogenous and/or endogenous factors. In normal physiological conditions, these reactive species are maintained in an equilibrium state by the cells' antioxidant defence systems. In addition, they are recognised to play important roles in several physiological functions. However, when an imbalance in the equilibrium between oxidants and antioxidants occurs in favour of the former, we come to a situation defined as oxidative stress. ROS/RNS can cause damage to all biomolecules (namely proteins, lipids and DNA) and ultimately participate in the regulation of mechanisms leading to cell death, being implicated in the etiology of several pathologies (like neurodegenerative and cardiovascular diseases). To cope with oxidative stress, cells possess effective enzymatic (e.g. superoxide dismutase, catalase, glutathione peroxidase) and non-enzymatic (e.g. glutathione, thioredoxin, coenzyme Q) antioxidant systems. In addition, several compounds present in plants and vegetables (e.g. vitamins C and E, polyphenols) have been described to react with free radicals. However, some drawbacks associated to these natural compounds are in part responsible for the undergoing development of novel synthetic compounds capable of acting as antioxidants and protect cells against oxidative stress-induced cell death. Here, we review the basic mechanisms of ROS/RNS formation, as well as their interaction with biomolecules and regulation of cell death, in order to identify possible drug targets. We also report the importance of natural antioxidant systems and the ongoing research leading to the development of more powerful and effective antioxidant drugs.

Oxidative DNA damage protection and repair by polyphenolic compounds in PC12 cells

Biological systems are frequently exposed to excessive reactive oxygen species, causing a disturbance in the cells natural antioxidant defence systems and resulting in damage to all biomolecules, including nucleic acids. In fact, oxidative DNA damage is described as the type of damage most likely to occur in neuronal cells. In this study, three polyphenolic compounds, luteolin, quercetin and rosmarinic acid, were investigated for their protective effects against oxidative DNA damage induced in PC12 cells, a neuronal cell model. Although luteolin and quercetin prevented the formation of strand breaks to a greater extent than rosmarinic acid, this last one presented the highest capacity to repair strand breaks formation. In addition, rosmarinic acid was the only compound tested that increased the repair of oxidized nucleotidic bases induced with the photosensitizer compound [R]-1-[(10-chloro-4-oxo-3-phenyl-4H-benzo[a]quinolizin-1-yl) carbonyl]-2-pyrrolidine-methanol (Ro 19-8022). The activity of repair enzymes was indicated by the in vitro base excision repair assay, using a cell-free extract obtained from cells previously treated with the compounds to incise DNA. The protective effect of rosmarinic acid was further confirmed by the increased expression of OGG1 repair gene, observed through real time RT-PCR. The data obtained is indicative that rosmarinic acid seems to act on the intracellular mechanisms responsible for DNA repair, rather than by a direct effect on reactive oxygen species scavenging, as deducted from the effects observed for luteolin and quercetin. Therefore, these results suggest the importance of these polyphenols, and in particular rosmarinic acid, as protectors of oxidative stress-induced DNA damage that commonly occurs in several pathological conditions, such as neurodegenerative diseases.

A comparative study between two central veins for the introduction of totally implantable venous access devices in 1201 cancer patients

INTRODUCTION AND AIMS

The Subclavian vein has been traditionally the vein of choice for central venous catheterization by general surgeons. Alternative settings for the introduction of totally implantable venous access devices (TIVAD) and the search for lower rates of morbidity led to the choice of other central veins. This study compares two different venous accesses, the subclavian (SC) versus the internal jugular (IJ), in terms of early and late morbidity.

PATIENTS AND METHODS

This is a prospective, non-randomized, observational, uni-institutional (tertiary cancer centre) study. From March 2003 to March 2006, 1231 TIVADs were placed (1201 patients), in an ambulatory operating room, under vital signs and EKG monitoring, using local anaesthesia and without perioperative radiological control.

RESULTS

Of the 1231 TIVAD, 617 were inserted via the SC and 614 via the IJ vein. The two groups (SC vs. IJ) were comparable as to general patient characteristics. Immediate complications were more frequent in the SC than in the IJ approach (respectively, 5.0% vs. 1.5%; p<0.001); Catheter malposition occurred in 2.3% when using the SC vein and in 0.2% for the IJ (p=0.001). Long term morbidity was also more frequent in the SC than in the IJ group (respectively, 15.8%, 87/551, vs. 7.6%, 39/512; p<0.001). Venous thrombosis developed in 2.0% of patients with an SC TIVAD as compared to 0.6% with an IJ TIVAD (p=0.044). Catheter malfunction was significantly dependent on the vein used: SC - 9.4% vs. IJ - 4.3% (p=0.001).

CONCLUSIONS

Our results support the preferential use of the Internal Jugular vein for the insertion of TIVAD.

Oxidative stress protection by newly synthesized nitrogen compounds with pharmacological potential

In this study we used new nitrogen compounds obtained by organic synthesis whose structure predicted an antioxidant potential and then an eventual development as molecules of pharmacological interest in diseases involving oxidative stress. The compounds, identified as FMA4, FMA5, FMA7 and FMA8 differ in the presence of hydroxyl groups located in the C-3 and/or C-4 position of a phenolic unit, which is possibly responsible for their free radicals' buffering capacity. Data from the DPPH discoloration method confirm the high antiradical efficiency of the compounds. The results obtained with cellular models (L929 and PC12) show that they are not toxic and really protect from membrane lipid peroxidation induced by the ascorbate-iron oxidant pair. The level of protection correlates with the drug's lipophilic profile and is sometimes superior to trolox and equivalent to that observed for alpha-tocopherol. The compounds FMA4 and FMA7 present also a high protection from cell death evaluated in the presence of a staurosporine apoptotic stimulus. That protection results in a significant reduction of caspase-3 activity induced by staurosporine which by its turn seems to result from a protection observed in the membrane receptor pathway (caspase-8) together with a protection observed in the mitochondrial pathway (caspase-9). Taken together the results obtained with the new compounds, with linear chains, open up perspectives for their use as therapeutical agents, namely as antioxidants and protectors of apoptotic pathways. On the other hand the slight pro-oxidant profile obtained with the cyclic structures suggests a different therapeutic potential that is under current investigation.

Kinetics of eosinophil and IgE-mast cell changes following infection with Angiostrongylus costaricensis in Wistar rats

Human abdominal angiostrongyliasis is a severe eosinophilic disease caused by Angiostrongylus costaricensis. Previous studies have demonstrated that wild rodents are critically involved as definitive hosts to this nematode in nature. In this study, we have evaluated the susceptibility of Wistar rats (Rattus norvegicus) to A. costaricensis infection. Kinetics of parasitological and pathological changes, including the number of adult worms recovered from mesenteric arteries, and of IgE, mast cell and eosinophil levels in several compartments have been assessed. The oral inoculation of third-stage larvae (L3) into adult Wistar rats led to a marked accumulation of worms in the branches of the mesenteric arteries 25 and 50 days post-inoculation. Intense bone marrow eosinophilia ranging from 7 to 50 days was accompanied by marked accumulation of eosinophils in the blood, peritoneal and bronchoalveolar spaces. Eosinophilic periarteritis, oedema and granuloma in the intestinal and lung tissues were also histologically evident. Total serum IgE and specific anti-parasite IgE peaked at 25 days post-infection, as measured by ELISA and by the passive cutaneous anaphylaxis test, respectively. At that time point, there was a drastic reduction in the number of intact mast cells in the peritoneal effluent. These findings indicate that Wistar rats are permissive to A. costaricensis infection. IgE-mast cell activation and massive tissue eosinophil infiltration are marked features in the process and are likely to play a crucial role in the immune-response evoked by this parasite.

Late-onset corticohippocampal neurodepletion attributable to catastrophic failure of oxidative phosphorylation in MILON mice

We generated mitochondrial late-onset neurodegeneration (MILON) mice with postnatal disruption of oxidative phosphorylation in forebrain neurons. They develop normally and display no overt behavioral disturbances or histological changes during the first 5 months of life. The MILON mice display reduced levels of mitochondrial DNA and mitochondrial RNA from 2 and 4 months of age, respectively, and severely respiratory chain-deficient neurons from 4 months of age. Surprisingly, these respiratory chain-deficient neurons are viable for at least 1 month without showing signs of neurodegeneration or major induction of defenses against oxidative stress. Prolonged neuronal respiratory chain deficiency is thus required for the induction of neurodegeneration. Before developing neurological symptoms, MILON mice show increased vulnerability to excitotoxic stress. We observed a markedly enhanced sensitivity to excitotoxic challenge, manifest as an abundance of terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling (TUNEL) reactive cells after kainic acid injection, in 4-month-old MILON mice, showing that respiratory chain-deficient neurons are more vulnerable to stress. At approximately 5-5.5 months of age, MILON mice start to show signs of disease, followed by death shortly thereafter. The debut of overt disease in MILON mice coincides with onset of rapidly progressive neurodegeneration and massive cell death in hippocampus and neocortex. This profound neurodegenerative process is manifested as axonal degeneration, gliosis, and abundant TUNEL-positive nuclei. The MILON mouse model provides a novel and powerful tool for additional studies of the role for respiratory chain deficiency in neurodegeneration and aging.

Modulation of eotaxin formation and eosinophil migration by selective inhibitors of phosphodiesterase type 4 isoenzyme

1. This study was undertaken to investigate the possible contribution of the blockade of eotaxin generation to the anti-eosinophilotactic effect of phosphodiesterase (PDE) type 4 inhibitors. In some experiments, the putative synergistic interaction between PDE type 4 inhibitors and the beta2-agonist salbutamol was also assessed. 2. Sensitized guinea-pigs aerosolized with antigen (5% ovalbumin, OVA) responded with a significant increase in eotaxin and eosinophil levels in the bronchoalveolar lavage fluid (BALF) at 6 h. Eosinophil recruitment was inhibited by both PDE type 4 inhibitors rolipram (5 mg kg(-1), i.p.) and RP 73401 (5 mg kg(-1), i.p.) treatments. In contrast, only rolipram inhibited eotaxin production. 3. Sensitized rats intrapleurally challenged (i.pl.) with antigen (OVA, 12 microg cavity(-1)) showed a marked eosinophil infiltration at 24 h, preceded by eotaxin generation at 6 h. Intravenous administration of a rabbit anti-mouse eotaxin antibody (0.5 mg kg(-1)) significantly reduced allergen-evoked eosinophilia in this model. 4. Local pretreatment with rolipram (40 microg cavity(-1)) or RP 73401 (40 microg cavity(-1)) 1 h before challenge reduced eosinophil accumulation evaluated in the rat pleural effluent, but only the former was active against eotaxin generation. The inhibitors of PDE type 3 (SK&F 94836) and type 5 (zaprinast) failed to alter allergen-evoked eosinophil recruitment in rats. 5. Local injection of beta2-agonist salbutamol (20 microg cavity(-1)) inhibited both eosinophil accumulation and eotaxin production following pleurisy. The former was better inhibited when salbutamol and rolipram were administered in combination. 6. Treatment with rolipram and RP 73401 dose-dependently inhibited eosinophil adhesion and migration in vitro. These effects were clearly potentiated by salbutamol at concentrations that had no effect alone. 7. Our findings indicate that although rolipram and RP 73401 are equally effective in inhibiting allergen-induced eosinophil infiltration only the former prevents eotaxin formation, indicating that PDE 4 inhibitors impair eosinophil accumulation by mechanisms independent of eotaxin production blockade.

Increased in vivo apoptosis in cells lacking mitochondrial DNA gene expression

We have attempted to determine whether loss of mtDNA and respiratory chain function result in apoptosis in vivo. Apoptosis was studied in embryos with homozygous disruption of the mitochondrial transcription factor A gene (Tfam) and tissue-specific Tfam knockout animals with severe respiratory chain deficiency in the heart. We found massive apoptosis in Tfam knockout embryos at embryonic day (E) 9.5 and increased apoptosis in the heart of the tissue-specific Tfam knockouts. Furthermore, mtDNA-less (rho(0)) cell lines were susceptible to apoptosis induced by different stimuli in vitro. The data presented here provide in vivo evidence that respiratory chain deficiency predisposes cells to apoptosis, contrary to previous assumptions based on in vitro studies of cultured cells. These results suggest that increased apoptosis is a pathogenic event in human mtDNA mutation disorders. The finding that respiratory chain deficiency is associated with increased in vivo apoptosis may have important therapeutic implications for human disease. Respiratory chain deficiency and cell loss and/or apoptosis have been associated with neurodegeneration, heart failure, diabetes mellitus, and aging. Furthermore, chemotherapy and radiation treatment of cancer are intended to induce apoptosis in tumor cells. It would therefore be of interest to determine whether manipulation of respiratory chain function can be used to inhibit or enhance apoptosis in these conditions.

Using kaon regeneration to probe the quark mixing parameter cos2beta in B --> psiK decays

We suggest a novel method to determine the sign of cos2beta in the decays B --> psiK, by creating interference between K(L) and K(S) final states via "regeneration," that is propagation through a matter target region to convert some K(L) to K(S). The determination of this quantity resolves an ambiguity between beta and 90 degrees -beta that remains after the standard measurements of sin2beta and may turn out to be important in resolving whether the result is in agreement with standard model predictions or indicates the presence of new physics. We find the measurement is feasible at a B factory, but requires several years of high-luminosity running with a regeneration target affecting a significant fraction of the detector.

Impaired insulin secretion and beta-cell loss in tissue-specific knockout mice with mitochondrial diabetes

Mitochondrial dysfunction is an important contributor to human pathology and it is estimated that mutations of mitochondrial DNA (mtDNA) cause approximately 0.5-1% of all types of diabetes mellitus. We have generated a mouse model for mitochondrial diabetes by tissue-specific disruption of the nuclear gene encoding mitochondrial transcription factor A (Tfam, previously mtTFA; ref. 7) in pancreatic beta-cells. This transcriptional activator is imported to mitochondria, where it is essential for mtDNA expression and maintenance. The Tfam-mutant mice developed diabetes from the age of approximately 5 weeks and displayed severe mtDNA depletion, deficient oxidative phosphorylation and abnormal appearing mitochondria in islets at the ages of 7-9 weeks. We performed physiological studies of beta-cell stimulus-secretion coupling in islets isolated from 7-9-week-old mutant mice and found reduced hyperpolarization of the mitochondrial membrane potential, impaired Ca(2+)-signalling and lowered insulin release in response to glucose stimulation. We observed reduced beta-cell mass in older mutants. Our findings identify two phases in the pathogenesis of mitochondrial diabetes; mutant beta-cells initially display reduced stimulus-secretion coupling, later followed by beta-cell loss. This animal model reproduces the beta-cell pathology of human mitochondrial diabetes and provides genetic evidence for a critical role of the respiratory chain in insulin secretion.

Complex genetic counselling and prenatal analysis in a woman with external ophthalmoplegia and deleted mtDNA

Single large mitochondrial DNA deletions (DeltamtDNA) are usually spontaneously occurring and cause a wide variety of symptoms, ranging from severe infantile multisystem disorders to adult onset progressive external ophthalmoplegia (PEO). There is always heteroplasmy with a mixture of normal and mutant mtDNA and the levels usually vary widely between tissues. There is at present insufficient scientific basis for accurate genetic counselling of women with DeltamtDNA, but it is reasonable to assume that DeltamtDNA can be transmitted if it is present in the female germ cells. Here, we present the results of prenatal analysis in a woman with DeltamtDNA and PEO. No DeltamtDNA was detected by Southern blot and PCR analyses of chorionic villi from the first trimester of pregnancy, in cord blood obtained at birth or in peripheral blood from the child at six months of age. This makes it unlikely that the child will develop a severe infantile mitochondrial disorder due to transmission of high levels of DeltamtDNA. However, the complex mitochondrial genetics and the limited access to human tissues makes it impossible to exclude transmission of low levels of DeltamtDNA that possibly could cause disease later in life.

Merkel cell carcinoma of the eyelid: a case report

A 22-year-old woman who presented with a tumour of the upper eyelid with clinical, histological, immunohistochemical and ultrastructural features of a Merkel cell carcinoma is reported. This is a unique case of Merkel cell carcinoma in such a young patient. This neuroendocrine tumour is typically found in the elderly. It can grow rapidly, has the potential for local recurrence and early metastatic spread. The authors recommend wide resection of the primary site, which proved effective in this case.