Comparison of B-mode and Doppler ultrasonographic findings with histologic features of benign and malignant superficial lymph nodes in dogs

OBJECTIVE: To compare and correlate B-mode and color Doppler ultrasonographic characteristics with histopathologic findings of benign and malignant superficial lymph nodes in dogs. STUDY POPULATION: 50 superficial lymph nodes that were normal, abnormally large on physical examination, or represented regional lymph nodes draining an area of suspected primary malignancy in 30 dogs. PROCEDURES: Before excision, lymph nodes were evaluated via B-mode and color Doppler ultrasonography to assess size, echogenicity, presence of a hilus, acoustic transmission, and vascular flow. Formalin-fixed, paraffin-embedded tissue sections of excised lymph nodes were stained with H&E and examined for the presence and extent of necrosis, fibrosis, fat, metastases, and tissue heterogeneity. To assess vascularity, the number and distribution of vessels stained by the Verhoeff van Gieson technique were recorded. RESULTS: In superficial lymph nodes, a varied echogenicity corresponded to tissue heterogeneity. The ultrasonographic detection of a hilus was associated with the presence of fibrous tissue, fat, or both in the hilar region. Acoustic enhancement corresponded to presence of areas of intranodal necrosis. There was significant correlation between both the distribution and the number of vessels detected via ultrasonography and that detected by histopathology. The amount of flow estimated via ultrasonography was typically higher than that estimated via histologic examination. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that histopathologic changes in canine lymph nodes have associated ultrasonographic changes and suggest that lymph node ultrasonography has an important role in the evaluation of lymph nodes in dogs in general and in dogs with neoplastic disease in particular.     

Variation of extractives content in heartwood and sapwood of Eucalyptus globulus trees

The variation in extractives content in sapwood and heartwood was investigated among 12 trees in each of four commercial plantations of Eucalyptus globulus in central Portugal. The study was carried out at the 15% height level and extractions used successively dichloromethane, ethanol and water. At all sites, heartwood had significantly more extractives than sapwood, on average 3.8 and 2.4%, respectively. Most extractives consisted of ethanol soluble material (on average 52% of total extractives). Among the sites, there was a statistically significant difference in the content of extractives but the most important source of variation was the within-tree variation between sapwood and heartwood. Differences in the content of extractives were also observed among trees. A strong relation between extractives content and heartwood proportion was found. The potential loss of pulp yield and problems associated with accumulation of extractives are directly related to the heartwood proportion in the eucalypt stems. Forest management should take into account heartwood development and selection for minimising heartwood extractives.     

Assessing heavy metal contamination in soils of the Zagreb region (Northwest Croatia) using multivariate geostatistics

The assessment of soil contamination and location of pollution sources represent a crucial issue in soil remediation. Topsoil samples were collected in the Zagreb area (Northwest Croatia) and the total contents of trace and major elements were determined. A multivariate geostatistical analysis was used to estimate soil chemical composition variability. Factorial Kriging Analysis (FKA) was used to investigate the scale-dependent correlation structure of some variables by modelling co-regionalization of ten chemical variables, co-kriging specific factors and mapping them. The FKA provided two regionalized factors at different spatial scales of variability: the first factor at shorter range for Zn, Pb, Cd, Cu and Ni indicated different sources of anthropogenic contamination, whereas Ca (mainly loading on the longer range factor) was related to the lithology and parent material composition. The methodology used has proved to be a useful tool to separate geological and anthropogenic causes of variation in soil heavy metal content and to identify common pollution sources.     

Cellular structure and chemical composition of cork from the Chinese cork oak (Quercus variabilis)

Quercus variabilis Blume, the Chinese cork oak, is an oak species with a thick cork outer bark. The cork is exploited at a limited scale in China and considered of lower quality than the commercial cork from Quercus suber. We studied an industrial cork granulate feedstock of Q. variabilis in relation to cellular structure and chemical composition and compared it to Q. suber cork under a material’s perspective. The cork of Q.variabilis has 1.1 % ash, 9.6 % extractives, 34.8 % suberin and 19.1 % lignin. The monosaccharide composition with shows a predominance of hemicelluloses: glucose 42.8 % of total neutral sugars, xylose 27.5 %, arabinose 15.4 %, galactose 9.0 %, mannose 4.0 %, rhamnose 1.2 %. The FT-IR spectrum shows the indicative peaks of suberin. The composition is overall similar to that of Q. suber cork. Q. variabilis cork has the typical cellular characteristics of bark cork tissues with a regular and radially aligned structure of cells without intercellular voids. Solid volume fraction was estimated at approximately 16 %. Compared with Q. suber, the Q. variabilis cork cells are smaller, the cell wall undulation and the overall row alignment less homogeneous, the cell surface is irregular and the solid volume proportion higher. The characteristics of Q. variabilis cork support its use as a cellular material for sealing, insulation and energy absorption, but the overall quality is lower than that of Q. suber cork. The negative impact of the higher density and structural lower uniformity at tissue and cell level should be evaluated for processing and product performance.     

Efficient Screening of Marine Extracts for Protease Inhibitors by Combining FRET Based Activity Assays and Surface Plasmon Resonance Spectroscopy Based Binding Assays

The screening of extracts from marine organisms is a widely used strategy to discover new drug leads. A common problem in the screening process is the generation of false positive hits through unspecific effects from the complex chemical composition of the crude extracts. In this study, we explored a combination of a fluorescence resonance energy transfer (FRET) based activity assay and a surface plasmon resonance (SPR) based binding assay to avoid this problem. An aqueous extract was prepared from rest raw material of the Norwegian spring spawning herring, and further fractionated by methanol solubility and solid phase extraction. FRET based activity assays were used to determine the influence of each extract on the activity of different proteases. Several extracts showed more than 50% inhibition. The inhibition mechanisms were elucidated by SPR based competition experiments with known inhibitors. For the secreted aspartic proteases 1, 2, 3 and HIV-1 protease, the results indicated that some extracts contain inhibitors interacting specifically with the active site of the enzymes. The study shows that a combination of an activity assay and an SPR based binding assay is a powerful tool to identify potent inhibitors in marine extracts. Furthermore, the study shows that marine vertebrates offer an interesting source for new bioactive compounds, although they have rarely been explored for this purpose.     

Extracts of Peels and Seeds of Five Varieties of Brazilian Jabuticaba Present High Capacity to Deactivate Reactive Species of Oxygen and Nitrogen

Plant Foods for Human Nutrition - Jabuticaba has a high concentration of phenolic compounds, which have a significant antioxidant capacity. Methodologies have been developed to evaluate the ability...     

Identification of unreported putative new bovine papillomavirus types in Brazilian cattle herds

The amplification by degenerate primers FAP59/FAP64 and sequencing allowed the detection of 15 putative new BPV types in cutaneous warts as well as in healthy skin. Four of these isolates were recently recognized as new BPV types (BPV-7, -8, -9, and -10) after determination of their complete genome sequences. In Brazil, investigations involving the definition of BPV types present in skin warts are still rare. The aim of the current study was to identify the BPV types associated with cutaneous papillomatosis observed in Brazilian cattle herds. Twenty-two cutaneous papilloma specimens were submitted to PCR assay employing the FAP primer pair. All PCR products with approximately 480 bp were submitted to direct sequencing. Cloning was performed for the amplicons which prior analysis revealed as putative new BPV types. From 16 cutaneous lesions, BPV-1, -2, and -6 were identified in two, six, and eight papilloma specimens, respectively. In addition, four putative new BPV types were identified in other six skin warts, and then designated as BPV/BR-UEL2 to -5. The detection of the BPV-1, -2, and -6 types in skin wart specimens supports the existence of these BPV types throughout the Brazilian cattle herd. In addition, the identification of four putative new BPV types is the first report of the presence of different BPV types in the American continent.     

Dasatinib inhibition of cSRC prevents the migration and metastasis of canine mammary cancer cells with enhanced Wnt and HER signalling

Human epidermal growth factor 2 (HER2) overexpression leads to aggressive mammary tumour growth. Although the prognosis of HER2⁺ tumours in humans is greatly improved using biologicals, therapy resistance, which may be caused by increased phosphatidyl‐3‐kinase (PI3K), rous sarcoma proto‐oncogene (cSRC) or wingless‐type MMTV integration site family (Wnt) activity, is a major concern. A recent analysis of 12 canine mammary cell lines showed an association between HER2/3 overexpression and phosphatase and tensin homologue (PTEN) deletion with elevated Wnt‐signalling. Wnt‐activity appeared to be insensitive to phosphatidyl‐3‐kinase (PI3K) inhibitors but sensitive to Src‐I1. We hypothesized that Wnt activation, was caused by HER2/3‐activated cSRC activation. The role of HER2/3 on Wnt signalling was investigated by silencing HER2/3 expression using specific small interfering RNA (siRNAs). Next, the effect of an epidermal growth factor receptor (EGFR)/HER2 tyrosine kinase inhibitor on Wnt activity and migration was investigated and compared to other tyrosine kinase inhibitors (TKIs) of related signalling pathways. Finally, two TKIs, a cSRC and a PI3K inhibitor, were investigated in a zebrafish xenograft model. Silencing of HER1‐3 did not inhibit the intrinsic high Wnt activity, whereas the HER kinase inhibitor afatinib showed enhanced Wnt activity. The strongest inhibition of Wnt activity and cell viability and migration was shown by cSRC inhibitors, which also showed strong inhibition of cell viability and metastasis in a zebrafish xenograft model. HER2/3 overexpression or HER2/3‐induced cSRC activation is not the cause of enhanced Wnt activity. However, inhibition of cSRC resulted in a strong inhibition of Wnt activity and cell migration and metastasis. Further studies are needed to unravel the mechanism of cSRC activation and cSRC inhibition to restore sensitivity to HER‐inhibitors in HER2/3‐positive breast cancer.     

Behavioral and physiological evaluation of sows raised in outdoors systems in the Brazilian semiarid region

Tropical Animal Health and Production - The objective of this study was to evaluate the biochemical, behavioral, and physiological parameters in pregnant sows of native and improved crossbreeds...