Flat Coatings Research Articles

Canine Histiocytic and Hemophagocytic Histiocytic Sarcomas Display KRAS and Extensive PTPN11/SHP2 Mutations and Respond In Vitro to MEK Inhibition by Cobimetinib.

Histiocytic sarcoma (HS) is a rare and highly aggressive cancer in humans and dogs. In dogs, it has a high prevalence in certain breeds, such as Bernese mountain dogs (BMDs) and flat-coated retrievers. Hemophagocytic histiocytic sarcoma (HHS) is a unique form of HS that presents with erythrophagocytosis. Due to its rareness, the study of HHS is very limited, and mutations in canine HHS patients have not been studied to date. In previous work, our research group identified two major PTPN11/SHP2 driver mutations, E76K and G503V, in HS in dogs. Here, we report additional mutations located in exon 3 of PTPN11/SHP2 in both HS and HHS cases, further supporting that this area is a mutational hotspot in dogs and that mutations in tumors and liquid biopsies should be evaluated utilizing comprehensive methods such as Sanger and NextGen sequencing. The overall prevalence of PTPN11/SHP2 mutations was 55.8% in HS and 46.2% in HHS. In addition, we identified mutations in KRAS, in about 3% of HS and 4% of HHS cases. These findings point to the shared molecular pathology of activation of the MAPK pathway in HS and HHS cases. We evaluated the efficacy of the highly specific MEK inhibitor, cobimetinib, in canine HS and HHS cell lines. We found that the IC50 values ranged from 74 to 372 nM, which are within the achievable and tolerable ranges for cobimetinib. This finding positions cobimetinib as a promising potential candidate for future canine clinical trials and enhances our understanding of the molecular defects in these challenging cancers.

Cryogenic quenching process enhancement through coating and microstructure optimization

In this work, we explore the impact of coatings and microstructures on heat transfer during a cryogenic quenching process. An easily reproducible quenching test is presented as a benchmark for testing different solutions. The study involves two different flat polymeric coatings as well as three porous microstructures. The results show that pairing a low-conductive coating with an appropriate porous surface microstructure on top of a stainless-steel plate can reduce the chill down time, accelerating the transition from room temperature to liquid nitrogen temperature, by a factor of five. High speed video recordings have been used to analyse the quenching process with different coatings and microstructures showing how the suppression of the film boiling regime is the key to enhancing the quenching process.

The effect of body size and inbreeding on cancer mortality in breeds of the domestic dog: a test of the multi-stage model of carcinogenesis.

Cancer is a leading cause of death in domestic dogs. Deaths due to cancer vary widely among breeds, providing an opportunity for testing the multi-stage model of carcinogenesis. This model underpins evolutionary and basic studies of cancer suppression and predicts a linear increase in cancer with breed size, an expectation complicated by bigger breeds having a shorter lifespan (decreasing risk). Using three independent datasets, the weight and lifespan of breeds provided a good fit of lifetime cancer mortality to the multi-stage model, the fit suggesting many canine cancers are initiated by four driver mutations. Of 85 breeds in more than one dataset, only flat-coated retriever showed significantly elevated cancer mortality, with Scottish terrier, Bernese mountain dog and bullmastiff also showing notable risk (greater than 50% over expected). Analysis of breed clades suggested terriers experience elevated cancer mortality. There was no evidence that the lower mass-specific metabolic rate of larger breeds reduced cancer risk. Residuals indicated increased breed inbreeding shortened expected lifespan, but had no overall effect on cancer mortality. The results provide a baseline for identifying increased breed risk for specific cancers and demonstrate that, unless selection promotes increased cancer suppression, the evolution of larger longer-lived animals leads to a predictable increased cancer risk.

Impact of palliative-intent radiotherapy with or without chemotherapy on lameness in flat coat retrievers with localised periarticular histiocytic sarcoma - a retrospective cohort, single institution study.

Histiocytic sarcoma (HS) is a common tumour in flat coat retrievers (FCRs) often affecting periarticular tissues and joints. Palliative-intent radiotherapy, seeks to achieve local tumour control, pain relief and improve limb function. However, the effect of palliative-intent radiotherapy on analgesic levels of dogs with localised HS has not been studied. We hypothesised that palliative-intent radiotherapy could improve lameness in dogs affected by localised HS. This study aimed to assess the impact of palliative-intent radiotherapy on lameness of FCRs with localised HS. A retrospective cohort single institution study was performed. Medical records of FCR dogs with HS that received external beam radiotherapy between 2003 and 2022 were reviewed and included demographic, staging, severity of baseline lameness, therapeutic management and outcome data. Descriptive statistics, McNemar's chi-squared test, Fisher's exact test and Kaplan-Meier analysis were used for statistical analysis. Thirty-nine dogs were included with a median age of 7.2 years, 25 were male and 14 were female. HS was most commonly located in the forelimb (29 dogs, 74.3%), affecting the shoulder joint (19 dogs, 48.7%). Staging was performed in all 39 dogs with 22 (56.4%) dogs having localised HS, six (15.3%) dogs had localised HS with node metastasis and 11 (28.2%) dogs had localised HS with systemic metastasis. All dogs received palliative-intent hypo-fractionated radiation therapy, 32 (82%) dogs showed improvement in lameness. In conclusion, palliative intent radiation treatment has an analgesic effect reducing lameness or clinical signs associated with affected tumour-bearing joints.

Metastatic Cutaneous Langerhans Cell Histiocytosis in a Flat-Coated Retriever Treated with Doxorubicin and Prednisone.

A 2 yr old female intact flat-coated retriever dog was presented for evaluation of a histologically diagnosed cutaneous Langerhans cell histiocytosis of the muzzle with right mandibular nodal metastasis and suspected prescapular lymph node metastasis. Chemotherapy (lomustine 60 mg/m2 by mouth as a single dose) and glucocorticoid therapy (prednisone ∼20 mg/m2 by mouth every 24 hr) were initiated. Progressive disease occurred 21 days after lomustine administration. Doxorubicin (at 30 mg/m2 IV every 3 wk) was administered as a second-line therapy. Prednisone was continued at the same dose. Partial response was noted 1 wk after initiation of doxorubicin and sustained through doxorubicin #2. Complete remission was achieved following doxorubicin #3 (63 days from the start of doxorubicin rescue therapy). Progressive disease was noted after doxorubicin #5, for a total duration of response to doxorubicin of 105 days. Further rescue treatment with vinorelbine at 15 mg/m2 IV was elected. Progressive disease and clinical decline were noted 1 wk after initiation of vinorelbine. The patient was euthanized because of clinical decline 126 days after histopathologic diagnosis and 114 days after chemotherapy treatment was initiated.

Incidence and the risk of occurrence of benign and malignant canine skin tumours in Poland - a five-year retrospective study.

The aim of the study was to compile data on the frequency and distribution of canine skin tumours and determine the risk of these being malignant as opposed to benign. This determination proceeded from tumour histogenesis and gave consideration to the dog's breed, sex, age and the anatomical location of tumours. This retrospective five-year epidemiological study included 3,139 canine skin tumours collected in Poland. A univariable logistic regression analysis was performed to determine the odds ratios (ORs) with 95% confidence intervals (CIs). Microscopic analysis showed a significant predominance of benign tumours (65.02%) as well as mesenchymal and melanocytic tumours (59.57%). The most frequently diagnosed were mast cell tumours, accounting for 13.79% of all skin tumours, and other common tumour types were lipomas (6.40%), haemangiopericytomas (5.96%) and malignant melanomas (4.65%). The risk of malignant versus benign tumours was 1.212 times higher in the female than in the male dogs. A higher risk of development of malignant epithelial tumours was found in boxers (OR 4.091), German shepherds (OR 4.085) and flat-coated retrievers (OR 43.596). A higher risk of development of malignant mesenchymal tumours was found in golden retrievers (OR 4.693), boxers (OR 2.342), bulldogs (OR 3.469) and Maltese (OR 2.757). The results may serve as a reference point for further studies of the complex biology of canine skin tumours.

Preparation of Molybdenum Coatings by Molten Salt Electrodeposition in Na3AlF6-NaF-Al2O3-MoO3 System

In this paper, electrodeposition of a molybdenum coating was conducted in Na3AlF6-NaF-Al2O3-MoO3 molten salts at 930 °C to investigate the availability of preparation of thick molybdenum coatings. The effects of current density and electrodeposition time on the morphology of the produced molybdenum coating were studied. With the increase of current density (10~70 mA·cm−2), the coating thickness was increased from 10 μm to 30 μm, with all the current efficiency above 97%. Under a current density of 30 mA/cm2, with the rise of electrodeposition time (10~60 min), three stages of the deposit growth were observed, including the formation of a large number of fine crystals, transformation into fibrous morphology and well-developed faceted grains. The formation of a large number of fine crystals at the initial stage of the electrodeposition could facilitate electroplating molybdenum coatings with good quality at higher current density and longer duration. Thus electrodeposition at a current density of 100 mA·cm−2 for 3 h has been performed, resulting in the preparation of relatively flat, dense, and coherent molybdenum coatings with a thickness of 140 μm on a nickel substrate, with a current efficiency above 85%. It is anticipated that the electrodeposition of molybdenum coatings in the present molten system is suitable for electroplating thick molybdenum coatings.

Immobilization of Phaffia rhodozyma cells in biopolymer for enhanced Cr(VI) bioremediation

The presented study investigated the use of Phaffia rhodozyma cells immobilized in natural biopolymer for improved bioremediation of toxic chromium compounds from aqueous solutions. Cells were immobilised in the shape of spheres (PRS) and flat coatings (PRC) with the use of sodium alginate. The bioremediation process was conducted through sorption and the reduction of Cr(VI). The biosorption was best described by the Langmuir isotherm model (R2 = 0.982, 0.985, 0.992 for Free cells, PRS and PRC, respectively) and for the kinetics, the Weber-Morris for unmodified cells and pseudo-second order model for PRS/PRC was the best fit according to the correlation coefficient (R2 >0.9). Fourier-transform infrared spectroscopy (FTIR) analysis showed that the sorption process is probably of chemical nature. The reduction of Cr(VI) to Cr(III) was carried out by the result of the difference between values obtained from colorimetry with the 1,5-diphenylcarbazide (DPC)–Cr(VI) complex and overall Cr concentration obtained from atomic absorbance spectrometry. The P. rhodozyma was able to detoxicate chromate up to 99%. The comparison of immobilization shapes showed that PRC has higher bioremediation properties than PRS by about 15% in terms of chromium removal from aqueous solutions. The 3 cycles of adsorption/desorption without decrease in efficiency showed that the PRS and PRC can be used multiple times for the removal of chromium ions from environment.

Prevalence of dog erythrocyte antigen 1 in a population of dogs tested in California.

Multiple studies have evaluated the breed-specific prevalence of dog erythrocyte antigen (DEA) 1 in various geographic regions. However, few large-scale studies exist that describe breed prevalence of DEA 1 in the United States. From January 2000 to October 2020, 6469 dogs had their RBC antigen type determined and were included in the study. The overall prevalence of DEA 1 in all dogs was 61.2%. Of 50 breeds with sample sizes ≥20, 8 breeds had a high prevalence (≥90%) of DEA 1-positive blood type: Basset Hound, Bernese Mountain Dog, Brittany, Dachshund, Miniature Pinscher, Miniature Schnauzer, Pug, and Rottweiler. Four breeds had a high prevalence (≥90%) of DEA 1-negative blood type: Boxer, English Bulldog, Flat-Coated Retriever, and French Bulldog. Numerous breeds with a sample size <20 and ≥5 were found to have 100% prevalence of a DEA 1 blood type, although these findings need to be confirmed with a larger sample size. No statistical difference in any breed based on sex was found. The results in this study are consistent with previously reported data in other countries. Knowledge of regional breed differences in DEA 1 prevalence can help to improve selection and recruitment of appropriate blood donor dogs.

Flat Absorber Black PEO coatings on Ti6Al4V for spacecraft thermal control application

Black appearance and flat absorber, i.e., high solar absorptance (αs) and high IR emittance (εir) surfaces, are essential for optical benches and optical mounts in astronomical and scientific payloads/spacecraft. Generally, these optical benches and optical mounts are fabricated by Ti6Al4V alloy due to its superior mechanical and thermal properties. However, bare Ti6Al4V is restricted for spacecraft thermal control applications due to its low emittance, intermediate absorptance, and moderate corrosion resistance behaviors. Hence, plasma electrolytic oxidation (PEO) technique was utilized to develop black and flat absorber coatings on bare Ti6Al4V alloy. Sodium silicate (SS), sodium hypophosphate (SHP), and potassium fluoride (KF) were used for the preparation of the electrolytic bath. Process parameters such as current density, duty cycle, frequency, the concentration of electrolytes, and duration were judiciously altered to get uniform PEO coatings with the flat absorbing property. Six numbers of PEO coatings were finally chosen for further in-depth characterizations as they showed adequate flat absorbing property. The phase composition, microstructure, roughness, and wettability of those PEO coatings were thoroughly studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), profilometry, and water contact angle measuring techniques, respectively. Thermo-optical properties viz., εir and αs of the coatings were recorded by portable IR emissometer and solar reflectometer, respectively, and electrical sheet resistance was measured by two probe method. The Nanomechanical properties of the coatings, such as modulus (E) and nanohardness (H), were evaluated by the nanoindentation technique. The PEO coatings were also investigated with respect to potentiodynamic polarization to investigate corrosion resistance of the PEO coatings. The highest εir value of PEO coating was achieved as 0.87 for a 20% duty cycle with a combination of SS + SHP electrolytes, while the maximum αs value was achieved as 0.83 for the same 20% duty cycle with a combination of SS + SHP + KF electrolytes.

Evaluation of Left Ventricular Function in Healthy Retrievers Using Standard and 2D Speckle-Tracking Echocardiography.

Simple SummaryStandard echocardiography is an essential diagnostic tool for the assessment of cardiac performance in healthy and diseased animals. Two-dimensional speckle-tracking echocardiography is an advanced echocardiographic technique that is useful for the assessment of myocardial function. Factors such as dog breed, age, and body weight (BW) are known to influence the echocardiographic parameters. This study aimed to evaluate the effect of breed, age, and BW on the echocardiographic parameters in healthy Retrievers, including Flat-coated, Golden, and Labrador Retrievers. The results showed that there were no significant associations between breed and echocardiographic parameters. On the other hand, they revealed that left ventricular dimensions increased with BW. Furthermore, parameters including peak aortic blood flow velocity, trans-mitral rapid ventricular filling flow, the ratio of trans-mitral rapid ventricular filling flow to atrial contraction, and global radial strain were influenced by age.Standard echocardiography is vital for the assessment of cardiac performance in healthy and diseased animals. Similarly, two-dimensional speckle-tracking echocardiography (2D-STE) is an advanced echocardiographic technique that is becoming increasingly important for the assessment of myocardial function. Breeds, age, and body weight (BW) are known to be important factors affecting the echocardiographic parameters; therefore, the aim of this study was to evaluate the effect of breed, age, and BW on the echocardiographic parameters in three breeds of clinically healthy Retrievers. A total of 46 Retrievers, including 16 Flat-coated Retrievers (FR), 16 Golden Retrievers (GR), and 14 Labrador Retrievers (LR) were included in the study. The comparison of the breeds revealed significant differences in the LV wall thickness of FR and GR, although further analysis using MLR showed that the differences were most likely associated with BW, similarly to the other LV dimensions. Functional parameters, including ejection fraction, fractional shortening, and left-atrial-to-aortic ratio, were independent of breed, age, and BW. On the other hand, peak aortic blood flow velocity, trans-mitral rapid ventricular filling flow, and the ratio of trans-mitral rapid ventricular filling flow to atrial contraction were influenced by age. The 2D-STE-derived radial and circumferential strain parameters were independent of breed, age, and BW, except for global strain in the radial direction.

Comparison of the Clinical Characteristics of Histiocytic Sarcoma in Bernese Mountain Dogs and Flat-Coated Retrievers.

Simple SummaryHistiocytic sarcoma (HS) is a malignant hematopoietic tumor. It can affect any organ in the body and, therefore, can have a broad spectrum of clinical presentations. So far, no complete overview exists of the array of clinical aspects of HS in specific dog breeds in large groups. Therefore, we investigated the clinical characteristics of HS in a population of Bernese Mountain Dogs (BMD; n = 365) and Flat-Coated Retrievers (FCR; n = 289), which are two of the most affected dog breeds. The dogs were selected from veterinary pathology services, and each dog’s clinical and diagnostic characteristics were retrospectively collected. Localized HS was reported significantly more frequently in the FCR (60.6%) than in the BMD (39.2%), and disseminated HS was recorded significantly more frequently in the BMD (60.8%) than in the FCR (39.4%). Lameness as a clinical symptom was observed more frequently in the FCR, predominant in the front legs. With blood examination, the BMD had significantly more often leukocytosis and thrombocytopenia, while no difference in the occurrence of anemia was observed. Strikingly hypercalcemia was only observed in 15 BMD and in none of the FCR in which blood examination was performed. The new information provided in this study can aid the diagnostic process and allow for prompt treatment recommendations.Histiocytic sarcoma (HS) is an aggressive malignant tumor of histiocytes, which can affect almost any organ in the body and is characterized by a broad array of tumor locations and clinical presentations. So far, no complete overview exists of the array of clinical aspects of HS in specific dog breeds in large groups. Therefore, we investigated the clinical characteristics of HS in a population of Bernese Mountain Dogs (BMD; n = 365) and Flat-Coated Retrievers (FCR; n = 289), which are two of the most affected dog breeds. Cases were selected from databases from different pathology services, and clinical information was retrospectively collected for each case. Localized HS was reported significantly more frequently in the FCR (60.6%) than in the BMD (39.2%), and disseminated HS was recorded significantly more frequently in the BMD (60.8%) than in the FCR (39.4%). Lameness was seen more often in FCR than in BMD, and the vast majority (78.1%) of LHS leading to lameness was located in the front legs in the FCR, while in the BMD, there was a more even distribution. BMD had significantly more often leukocytosis and thrombocytopenia, even corrected for the type of HS, than FCR. No significant difference in the frequency of anemia was recorded between BMD and FCR. In those dogs in which blood examination was performed, hypercalcemia was diagnosed in 15 BMD, while none of the FCR had hypercalcemia. The new information provided in this study can aid the diagnostic process and allow for prompt treatment recommendations.

Fabrication of TiB2 coatings by electrophoretic deposition of synthesized TiB2 nanoparticles in molten salts

This paper presents a novel process for preparation of TiB2 coatings, which is a combination of synthesis of TiB2 nanoparticles by borothermal reduction of TiO2 in molten NaCl–KCl–AlF3 system and subsequent electrophoretic deposition of the as-synthesized TiB2 nanoparticles in the same molten salts system. The electrophoretic deposition under various cell voltages was carried out, which resulted in preparation of dense and relatively flat TiB2 coatings. The effect of applied cell voltages on the electrophoretic deposition rate and mechanical properties of produced TiB2 coatings has been presented. The thickness of the coatings increased with the rise of cell voltages due to elevated migration and deposition rate of TiB2 nanoparticles. The hardness of the fabricated TiB2 coatings was assessed by nanoindentation, indicating that the values of hardness and elastic modulus increased with elevated electrophoretic voltages, which probably has an influence on the structure of the TiB2 coatings. Under the cell voltage of 1.2 V, the values of hardness and elastic modulus could reach 32.4 ± 1.2 GPa and 420.2 ± 23.9 GPa, respectively. This proposed process should also be applied for preparation of additional types of transition metal diboride coatings.

Survey investigating the reasons why UK-based gundogs ceased working between 2010 and 2019.

To determine the longevity of the working life of gundogs in the UK, whether owners' considered retirement was premature and to identify risk factors associated with such work. A web-based survey seeking owner information as to the longevity of their dogs' working life and why they were retired, euthanised or died. The sample population is six hundred sixty-five dogs. The median age at which Springer spaniels stopped work was 11 years and for Cocker spaniels, it was 9 years. The median age for Labrador retrievers was 10 years; for Golden retrievers, 11 years and Flat-coated retrievers, 9.5 years. Cocker spaniels stopped work at a significantly younger age than Springer spaniels (p=0.0003) or Labrador retrievers (p=0.0407). There was no significant difference between the other major breeds. The majority of owners (54.3%) were satisfied with the working lifespan of their dog. Seventy per cent of dogs were retired, the three most prevalent reasons being lameness (25.2%), old age (23.7%) and deafness (7.8%). Forty-four dogs died (6.6%) and 158 (24%) were euthanised, with cancer (58%) being the most common reason. No work-related issues were identified and gundogs appear to have similar causes of mortality to the general canine population.

Nanostructured Zirconium‐Oxide Bioceramic Coatings Derived from the Anodized Al/Zr Metal Layers

AbstractHere, zirconium‐oxide ceramic coatings comprising arrays of 3D nanostructures are electrochemically synthesized, ranging in shape, size, spacing, and population density, termed as the nanomounds (ø≈65 nm), nanopillars (ø≈130 nm), and nanostumps (ø≈220 nm). The nanostructured coatings, alongside a flat ZrO2 anodic film, are explored as a potential biomaterial in experiments with Saos‐2 cells. All coatings reveal no cytotoxicity to living cells. The population density and spreading area of the cells, being the largest on the flat film, slightly decrease with increasing nanostructure dimensions. The cells progressively proliferate on all the surfaces, the nanomounds and, especially, nanopillars promoting the best viabilities and proliferation rates. The flat, nanomound, and nanopillar coatings promote the well‐defined organizations of actin filaments across the entire cell bodies with no disruption in the cytoskeletal network and the mature large dash‐shaped focal adhesions. The highest activity of alkaline phosphatase and the biggest deposition of a mineralization‐competent extracellular matrix occur on the nanopillar array, the other nanostructures showing a better result than the flat coating, though. The differences, paradoxes, and regularities in the cell responses are explained through the detailed consideration of the coating morphologies, surface chemistries, and processes at the cell/surface interfaces.

Multi-omics approach identifies germline regulatory variants associated with hematopoietic malignancies in retriever dog breeds.

Histiocytic sarcoma is an aggressive hematopoietic malignancy of mature tissue histiocytes with a poorly understood etiology in humans. A histologically and clinically similar counterpart affects flat-coated retrievers (FCRs) at unusually high frequency, with 20% developing the lethal disease. The similar clinical presentation combined with the closed population structure of dogs, leading to high genetic homogeneity, makes dogs an excellent model for genetic studies of cancer susceptibility. To determine the genetic risk factors underlying histiocytic sarcoma in FCRs, we conducted multiple genome-wide association studies (GWASs), identifying two loci that confer significant risk on canine chromosomes (CFA) 5 (Pwald = 4.83x10-9) and 19 (Pwald = 2.25x10-7). We subsequently undertook a multi-omics approach that has been largely unexplored in the canine model to interrogate these regions, generating whole genome, transcriptome, and chromatin immunoprecipitation sequencing. These data highlight the PI3K pathway gene PIK3R6 on CFA5, and proximal candidate regulatory variants that are strongly associated with histiocytic sarcoma and predicted to impact transcription factor binding. The CFA5 association colocalizes with susceptibility loci for two hematopoietic malignancies, hemangiosarcoma and B-cell lymphoma, in the closely related golden retriever breed, revealing the risk contribution this single locus makes to multiple hematological cancers. By comparison, the CFA19 locus is unique to the FCR and harbors risk alleles associated with upregulation of TNFAIP6, which itself affects cell migration and metastasis. Together, these loci explain ~35% of disease risk, an exceptionally high value that demonstrates the advantages of domestic dogs for complex trait mapping and genetic studies of cancer susceptibility.

Electrochemical preparation of W coatings in Na2WO4-WO3-ZrO2 molten salt

In this paper, the flat tungsten coatings with uniform grains were prepared via electrolytic tungsten at 1173 K in ternary molten salt system formed by tungstate, tungsten oxide and different mass fractions of ZrO2. Dense tungsten coatings containing the second phase of ZrO2 were obtained by constant direct current electrodeposition in molten salt, and the coatings have preferential growth orientation along the (2 1 1) crystal plane. These coatings were characterized via X–ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and laser scanning confocal microscope (LSCM). The results show that W-ZrO2 coating obtained at Na2WO4-WO3-ZrO2. In addition, the existence of zirconia in molten salt reduced the coating roughness from 13.567 μm to 3.017 μm, the current efficiency was lost from 84.15% to 70.76%, and the grains became fine and uniform. What’s more, the mechanical properties and thermal cycle performance of the coating have been effectively improved. To further illustrate the electrochemical process, the electrochemical behavior of tungsten ions and zirconium ions during the electrodeposition was investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV). The results indicated that the reduction reactions of tungsten ions and zirconium ions are divided into two steps, and the reaction processes are as follows: W(VI) → W(IV) → W, Zr(IV) → Zr(II) → Zr.

Identification of common predisposing loci to hematopoietic cancers in four dog breeds.

Histiocytic sarcoma (HS) is a rare but aggressive cancer in both humans and dogs. The spontaneous canine model, which has clinical, epidemiological, and histological similarities with human HS and specific breed predispositions, provides a unique opportunity to unravel the genetic basis of this cancer. In this study, we aimed to identify germline risk factors associated with the development of HS in canine-predisposed breeds. We used a methodology that combined several genome-wide association studies in a multi-breed and multi-cancer approach as well as targeted next-generation sequencing, and imputation We combined several dog breeds (Bernese mountain dogs, Rottweilers, flat-coated retrievers, and golden retrievers), and three hematopoietic cancers (HS, lymphoma, and mast cell tumor). Results showed that we not only refined the previously identified HS risk CDKN2A locus, but also identified new loci on canine chromosomes 2, 5, 14, and 20. Capture and targeted sequencing of specific loci suggested the existence of regulatory variants in non-coding regions and methylation mechanisms linked to risk haplotypes, which lead to strong cancer predisposition in specific dog breeds. We also showed that these canine cancer predisposing loci appeared to be due to the additive effect of several risk haplotypes involved in other hematopoietic cancers such as lymphoma or mast cell tumors as well. This illustrates the pleiotropic nature of these canine cancer loci as observed in human oncology, thereby reinforcing the interest of predisposed dog breeds to study cancer initiation and progression.

A facile strategy for fabricating self-sealing dense coating grown in-situ on porous silicon nitride ceramics

This present work explores initially the feasibility of producing in-situ surface oxidized coating on porous silicon nitride (Si3N4) ceramics. Theoretical prediction identifies the applied conditions of self-sealing strategy and oxidation time required to form dense coating. Experimentally, the porous Si3N4 ceramics with different pore structures were selected to fabricate in-situ oxidized coatings. The phase compositions, microstructures and mechanical properties of the porous Si3N4 ceramics were investigated before and after oxidation. The results show that flat and dense coatings are prevailed in all samples, which consist of amorphous SiO2 and its precipitates besides dominant Si3N4 phase. The strengthened substrate and strengthening effect of coating are the essential mechanisms associated with the improved mechanical properties. Self-sealing method seems to offer an inexpensive and efficient route to prepare coating on porous Si3N4 ceramics.

Prevalence of Canine Hip Dysplasia in Switzerland Between 1995 and 2016-A Retrospective Study in 5 Common Large Breeds.

Canine hip dysplasia (CHD) is a genetic disease, modulated by epigenetic and environmental factors. To decrease the prevalence of CHD, the hip joints of many pure breed dogs are radiographed to identify dysplastic dogs not qualified for breeding. It has been shown that both, prevalence and severity of CHD may be reduced on the basis of phenotypic i.e., radiographic selection of breeding animals. The method has been used in many countries for over 50 years. In the present study, severity and prevalence of CHD in five common large breeds in Switzerland were evaluated since 1995. Both, prevalence and severity of CHD dropped in each breed between the periods 1995–1999 and 2010–2016. The prevalence decreased in Golden Retrievers from 25 to 9% and in Labrador Retrievers from 16 to 3%, respectively. In the Flat-Coated Retriever, prevalence in general was low, decreasing from 6 to 3%. In the Bernese mountain dog and the German shepherd dog, a decrease from 21 to 12% and from 46 to 18%, respectively, was observed. However, the rather low overall rate of radiographed dogs (Retrievers: 11 to 18%, Bernese Mountain dogs: 23% and German Shepherd dogs: 31%) does not allow to draw reliable conclusions regarding the true prevalence of CHD for the entire population of these breeds in Switzerland.