Anatomical Mapping and Density of Merkel Cells in Skin and Mucosae of the Dog

Merkel cells (MCs) are specialized cutaneous receptor cells involved with tactile sense. Although the distribution of MCs has been extensively studied in humans and rodents, their precise distribution and density throughout skin in the dog has not previously been determined. Knowledge of their distribution could facilitate understanding of their functions. By using of immunohistochemistry, density, and anatomical mapping of the MCs population in the dog skin was determined. Assessment of the MCs innervation was also achieved. Different patterns were noted in epidermis, hair follicles, or mucosa, including variable‐sized clusters, linear or horse‐shaped arrangements, and scattered and individualized cells. MCs revealed great variations in density and distribution over the body surface, with the highest numbers in oral mucosa and facial skin. There was no correlation of MCs density with age, sex, type of breed, coat type or pigmentation. Between 41 and 65% of MCs in hairy and glabrous skin and 8–18% of MCs in oral mucosa were in intimate contact with intraepithelial axon terminals. These findings indicate that canine MCs are numerous in sensory receptive areas and may be associated with the tactile sense in the dog. The present article enhances the knowledge of the skin structure in this species. Anat Rec, 299:1157–1164, 2016. © 2016 Wiley Periodicals, Inc.     

Biodiversity and infrastructure interact to drive tourism to and within Costa Rica

Nature-based tourism has potential to sustain biodiversity and economic development, yet the degree to which biodiversity drives tourism patterns, especially relative to infrastructure, is poorly understood. Here, we examine relationships between different types of biodiversity and different types of tourism in Costa Rica to address three questions. First, what is the contribution of species richness in explaining patterns of tourism in protected areas and country-wide in Costa Rica? Second, how similar are the patterns for birdwatching tourism compared to those of overall tourism? Third, where in the country is biodiversity contributing more than other factors to birdwatching tourism and to overall tourism? We integrated environmental data and species occurrence records to build species distribution models for 66 species of amphibians, reptiles, and mammals, and for 699 bird species. We used built infrastructure variables (hotel density and distance to roads), protected area size, distance to protected areas, and distance to water as covariates to evaluate the relative importance of biodiversity in predicting birdwatching tourism (via eBird checklists) and overall tourism (via Flickr photographs) within Costa Rica. We found that while the role of infrastructure is larger than any other variable, it alone is not sufficient to explain birdwatching and tourism patterns. Including biodiversity adds predictive power and alters spatial patterns of predicted tourism. Our results suggest that investments in infrastructure must be paired with successful biodiversity conservation for tourism to generate the economic revenue that countries like Costa Rica derive from it, now and into the future.

The tourism sector is well-poised to generate win–win approaches to biodiversity conservation and sustainable development given its nonextractive nature and its dependence on scenic beauty (1). However, for sustainable tourism to succeed as a strategy for biodiversity conservation, the role that biodiversity plays in driving tourism patterns needs to be better understood. On one hand, wildlife and nature motivate a significant portion of global tourism (2), and protected areas with higher species richness tend to attract more tourists and yield higher economic benefits (3). On the other hand, tourism hotspots also tend to occur in places where more human-built infrastructure (e.g., hotels, roads, and airports) enables access (4, 5). Studies have reached mixed conclusions on the relative importance of biodiversity and accessibility for tourism, and little is known about how they work in concert (6–11). Given the potential negative impacts of infrastructure on biodiversity conservation, their relative contributions to tourism deserves explicit study, particularly in developing countries where both biodiversity conservation and sustainable development are urgently needed (7, 12).Drivers of tourism patterns across landscapes have been explored through questionnaire surveys and structured interviews that ask tourists about their affinity for landscape features (13–15) and through spatial models that predict recreation using photographs (e.g., geographically weighted regression, MaxEnt) (16, 17). Recently, geo-tagged photographs and species lists shared on social media platforms have become popular tools for tourism-focused research (18–22). These studies, however, typically focus narrowly on the role of single taxa (22, 23) and landscape attributes without accounting for species diversity (14, 20), or they focus only on the role of infrastructure as a driver of tourism (5). Recent advances in satellite Earth observations make it possible to capture more of the ecosystem heterogeneity that can drive variability in species distributions, compared to more conventional modeling based on land cover (24–26). An integrated approach is needed, linking species richness of multiple taxa along with infrastructure variables, both modeled and mapped through high resolution Earth observations. Such an approach could be scaled up to larger regions and applied globally, helping to identify where biodiversity is playing a significant role in driving tourism, such that governments and the tourism sector can prioritize investments in biodiversity conservation.Here, we ask three questions in the iconic case of Costa Rica. First, what is the contribution of species richness (of vertebrate taxa) in explaining patterns of tourism in protected areas and also country-wide? Second, how similar are the patterns for birdwatching tourism compared to those of overall tourism? Third, where in the country is biodiversity contributing more than other factors to birdwatching tourism and to overall tourism? We predict that vertebrate species richness is more important for driving tourism in protected areas than in the rest of the country, because nature-seeking tourists often go to protected areas to find wildlife (3). We also expect that birdwatching tourism is predicted by richness of threatened and endemic bird species rather than total species richness, given birdwatchers’ preferences for rare birds (27). We predict a saturating relationship between species richness and tourism, because beyond a large number of species additional species are unlikely to contribute more to tourism (28). Finally, we predict that national-level tourism is better explained by infrastructure (such as roads and hotels) and distance to water than by biodiversity, because tourists going to Costa Rica often seek activities such as surfing and relaxing in beach resorts (29, 30). We predict nonlinear effects of proximity to roads and water, because a place is deemed inaccessible if it is further away from roads, and a beach tourist destination is also either close to water or not a destination at all. Access diminishes rapidly over a few miles (31).To answer our research questions, we analyze patterns of tourism at two different spatial scales. First, we analyze tourism patterns in protected areas only. Many protected areas provide reliable data on visitation rates and biodiversity tends to be higher inside than outside protected areas (29). However, given that they are often visited by tourists who are already interested in biodiversity, protected areas are not representative of all tourism patterns (30). Second, we evaluate the relative importance of biodiversity to all tourism across Costa Rica (excluding offshore islands). Investigating tourism across the whole nation may give a better understanding of how biodiversity contributes to tourism writ large and not only for tourists with a predisposition for finding wildlife. At both the protected area and national scales, we use a modified MaxEnt model that integrates species distribution models for 66 terrestrial vertebrate species (including amphibians, reptiles, and mammals) and 699 bird species, based on remotely sensed climate and habitat variables, with spatial patterns of infrastructure (hotel density and distance to roads) and distance to water. We measure tourism in two ways for both scales: using eBird checklists as a proxy for birdwatching (32), and using Flickr photographs as a proxy for all international and domestic tourism (19).Costa Rica is an ideal country to explore these questions because tourism represents 7% of the national gross domestic product and employs 3% of the working population directly and a further 9% indirectly (33). Approximately 70% of all international visitors to Costa Rica state that the wildlife, dramatic scenery, and opportunities for adventure sports are the main motivation for visiting the country (33, 34). However, the importance of biodiversity as a factor that influences tourism to, or domestically within, the country has not been evaluated (apart from very local studies) (35, 36). The Central Bank of Costa Rica is currently piloting a nature-based tourism account under the United Nations System of Environmental Economic Accounts (UN SEEA). The state of the art with this methodology is to attribute value to different ecosystems, which may vary widely in their biodiversity. Understanding the relationships between biodiversity and tourism in Costa Rica is a key step toward maintaining the vibrant ecotourism industry and can serve as an example for other biodiverse nations that often look to Costa Rica as a leader in sustainable development (37).     

Therapeutic strategies involving survivin inhibition in cancer

Survivin is a small protein that belongs to the inhibitor of apoptosis protein family. It is abundantly expressed in tumors compared with adult differentiated tissues, being associated with poor prognosis in many human neoplasms. This apoptotic inhibitor has a relevant role in both the promotion of cancer cell survival and in the inhibition of cell death. Consequently, aberrant survivin expression stimulates tumor progression and confers resistance to several therapeutic strategies in a variety of tumors. In fact, efficient survivin downregulation or inhibition results in spontaneous apoptosis or sensitization to chemotherapy and radiotherapy. Therefore, all these features make survivin an attractive therapeutic target to treat cancer. Currently, there are several survivin inhibitors under clinical evaluation, although more specific and efficient survivin inhibitors are being developed. Moreover, novel combination regimens targeting survivin together with other therapeutic approaches are currently being designed and assessed. In this review, recent progress in the therapeutic options targeting survivin for cancer treatment is analyzed. Direct survivin inhibitors and their current development status are explored. Besides, the major signaling pathways implicated in survivin regulation are described and different therapeutic approaches involving survivin indirect inhibition are evaluated. Finally, promising novel inhibitors under preclinical or clinical evaluation as well as challenges of developing survivin inhibitors as a new therapy for cancer treatment are discussed.     

Genotoxicity and cytotoxicity of sevoflurane in two human cell lines in vitro with ionizing radiation

Objective:

To determine the in vitro toxicity of different concentrations of sevoflurane in cells exposed to X-ray.

Methods:

The genotoxic effects of sevofluorane were studied by means of the micronucleus test in cytokinesis-blocked cells of irradiated human lymphocytes. Subsequently, its cytotoxic effects on PNT2 (normal prostate) cells was determined using the cell viability test (MTT) and compared with those induced by different doses of X-rays.

Results:

A dose- and time-dependent cytotoxic effect of sevofluorane on PNT2 cells was determined (p >0.001) and a dose-dependent genotoxic effect of sevofluorane was established (p >0.001). Hovewer, at volumes lower than 30 μL of sevofluorane at 100%, a non-toxic effect on PNT2 cells was shown.

Conclusion:

Sevofluorane demonstrates a genotoxic capacity as determined in vitro by micronucleus test in cytokinesis-blocked cells of irradiated human lymphocytes.     

Comparative evaluation of the new version of the INNO-LiPA Mycobacteria and genotype Mycobacterium assays for identification of Mycobacterium species from MB/BacT liquid cultures artificially inoculated with Mycobacterial strains

The performance of two DNA line probe assays, a new version of INNO-LiPA Mycobacteria (Innogenetics, Ghent, Belgium) and the GenoType Mycobacterium (Hain Diagnostika, Nehren, Germany), were evaluated for identification of mycobacterial species isolated from liquid cultures. Both tests are based on a PCR technique and designed for simultaneous identification of different mycobacterial species by reverse hybridization and line probe technology. The INNO-LiPA Mycobacteria v2 targeting the 16S-23S rRNA gene spacer region was developed for the simultaneous identification of 16 different mycobacterial species. The GenoType Mycobacterium, which targets the 23S rRNA gene, allows simultaneous identification of 13 mycobacterial species. Both tests were evaluated on 110 mycobacterial strains belonging to 22 different mycobacterial species (20 reference strains, 83 clinical strains, and 4 Mycobacterium kansasii strains isolated from tap water) that were previously inoculated into MB/BacT bottles. The sensitivity of both methods, defined as the number of positive results obtained with the Mycobacterium genus probe together with an interpretable result on the number of samples tested was 110 of 110 (100%) for INNO-LiPA and 102 of 110 (92.7%) for GenoType. For samples with interpretable results, INNO-LiPA was able to correctly identify 109 of 110 samples (99.1%), whereas the GenoType correctly identified 100 of 102 samples (98.0%). Both tests were easy to perform, rapid, and reliable when applied to mycobacterial identification directly from MB/BacT bottles.     

High frequency of altered HLA class I phenotypes in invasive breast carcinomas

We studied 105 tumor samples obtained from patients diagnosed as having breast carcinomas for HLA class I and II (DR) antigen expression, using a panel of mAbs defining HLA-monomorphic, locus-specific and allele-specific determinants. Peripheral blood lymphocytes from patients were also typed for HLA alleles. The results indicated total HLA class I losses in 55 patients (52.3%), HLA-A locus losses in four patients (3.8%), HLA-B locus losses in eight patients (7.6%), and A, B, locus losses in 10 patients (9.5%). The remaining 28 patients whose tissues reacted positively with monomorphic- and locus-specific mAbs were tested for HLA allelic losses using several anti-HLA mAbs defining A2, A3, A9, B8, B12, etc. Of these 28 patients, 16 (57%) showed one or more losses of HLA reactivity. These results indicated that in 88.5% of patients we detected a particular HLA-altered tumor phenotype. The downregulation of HLA class I antigens in breast carcinomas may thus be more frequent than previously reported, and patients without HLA class I downregulation may be the exception rather than the rule. It cannot be ruled out that HLA alterations are present in some of the 12 patients with an apparently normal HLA phenotype, as some HLA alleles could not be studied because of the lack of appropriate mAbs. These HLA alterations could represent an important step associated with tumor invasion, conferring to the tumor cells the ability to escape from T-lymphocyte recognition.     

Multi-day radon signals with a radioactive decay limb -- occurrence and geophysical significance.

Multi-day signals, generally with duration of 2-10 days, are a prominent temporal variation type of radon (Rn) in geogas in the unsaturated zone. Rare multi-day Rn signals have been found which are characterized by: (a) a declining limb lasting up to 10 days which conforms to the radioactive decay of Rn, (b) recurs at the same location and (c) is recorded in diverse situations-volcanic and seismogenic. It suggested that a Rn blob is injected at a lower level on a steady upward flow of geogas whereby the rise and final fall of the signal are attributed to the edges of the blob while the central Rn-decay segment records the passing of the decaying blob itself. Rn-decay signals are a small subset of multi-day Rn signals which are considered as highly irregular and unusable for the understanding of geophysical processes. In difference, it is concluded that multi-day Rn signals are probably proxies of subtle geodynamic processes at upper crustal levels and are therefore significant for studying such processes.     

Bradicardia en la demencia frontotemporal

Introduction

Numerous regions of the brain, such as the medial frontal cortex, orbitofrontal cortex, insula, and amygdala, participate in the autonomic control of cardiovascular functions such as heart rate. The degenerative process in frontotemporal dementia (FTD) involves the listed anatomical structures and may therefore produce dysautonomic cardiovascular symptoms.

Aim

To observe whether or not non-cardiogenic bradycardia was more frequent in a group of patients with FTD than in subjects with mild cognitive impairment or dementia of a different aetiology.

Patients and method

Once patients with primary cardiac arrhythmia were excluded, we registered the heart rates of 258 patients with cognitive symptoms (36 with FTD, 22 with Alzheimer disease, 23 with vascular dementia, 10 with other dementias, and 167 with non-dementia cognitive impairment).

Results

Bradycardia (< 60 beats/minute) was significantly more frequent in patients with FTD. This difference remained significant after excluding subjects undergoing treatment with a potentially bradycardic effect. Bradycardia was more prevalent in behavioural FTD cases than in cases of the aphasic variant, and we detected a trend toward higher frequency among patients with more pronounced right hemisphere atrophy. Moreover, mean systolic blood pressure in FTD patients was lower than in other participants, and systolic hypotension (< 120 and < 100 mm Hg) was more prevalent.

Conclusion

Bradycardia was more frequent in the FTD sample than in other patients with cognitive symptoms. Further investigations will be necessary before we may consider bradycardia to be a sign supporting diagnosis of FTD or its behavioural variant.