Tailor made plasmin substrates as potential diagnostic tool to test for mastitis

Plasmin is a protease in milk, which concentration is increased during mastitis. The aim of the study was design and characterize short, tailor made fluorogenic substrates for plasmin to see differences in plasmin activity in healthy milk compared to mastitic milk. According to the specificity matrix of plasmin, containing 125 currently known plasmin substrates, six novel plasmin specific substrates were designed and characterized. Eight other substrates were insensitive for plasmin, which was in line with our expectations. The plasmin-sensitive substrates showed no cross-reactivity with proteases from mastitogenic bacteria in vitro. A proof of concept to distinguish healthy milk from mastitic milk is described. Potentially, these substrates present a rapid alternative to the currently established methodologies to detect mastitis in milk.     

The group self

Although people often tend to consider themselves and others as unique individuals, there are many situations in which they think, feel, and act primarily as group members. This can bring out the best in them, as when they are inspired to help fellow citizens in need, or the worst, as when they show hostility against others simply because they represent another religious or ethnic group. Understanding when and why the group self becomes more important than the individual self, and how this affects people's thoughts, feelings, and behaviors, can help to prevent and redirect unwelcome aspects of human behavior by addressing them at the appropriate level of self.     

Asymmetric segregation of polarized antigen on B cell division shapes presentation capacity

During the activation of humoral immune responses, B cells acquire antigen for subsequent presentation to cognate T cells. Here we show that after mouse B cells accumulate antigen, it is maintained in a polarized distribution for extended periods in vivo. Using high-throughput imaging flow cytometry, we observed that this polarization is preserved during B cell division, promoting asymmetric antigen segregation among progeny. Antigen inheritance correlates with the ability of progeny to activate T cells: Daughter cells receiving larger antigen stores exhibit a prolonged capacity to present antigen, which renders them more effective in competing for T cell help. The generation of progeny with differential capacities for antigen presentation may have implications for somatic hypermutation and class switching during affinity maturation and as B cells commit to effector cell fates.     

Anaplastic atypical myeloma with extensive cutaneous involvement in a dog

A 7-year-old, male, mixed breed dog was referred to the Veterinary Teaching Hospital at Kitasato University because of anorexia, lameness and multiple cutaneous lesions. Observation of bone marrow plasmacytosis, osteolytic bone lesions, serum myeloma protein and cutaneous infiltration of myeloma cells led us to a diagnosis of multiple myeloma (MM) with cutaneous involvement. Polymerase chain reaction and sequence analysis for the rearranged genes of immunoglobulin and T-cell receptor demonstrated that the neoplastic cells found in skin lesions or bone marrow are of B-lymphocyte lineage and share a common original precursor cell. The dog was treated with UW-Madison protocol or melphalan/prednisone protocol and survived 175 days. This is rare case of anaplastic MM with cutaneous involvement in dog.     

Constraints using the liquid fraction from roadside grass as a bio-based fertilizer

Background

Roadside grass cuttings are currently considered a waste product due to their association with road sweepings as contaminated waste, therefore, their potential as a biofertilizer is understudied.

Aim

This study aimed to determine whether grass liquid fraction (GLF) collected from a roadside verge in Maldegem, Belgium, and pressed using a screw press was suitable as a biofertilizer.

Methods

The characterization of the heavy metal content of the GLF was conducted using an ICP-OES. From May to September 2019, a pot experiment was set up using a randomized block design to compare tomato plant growth, yield, and nutrition for GLF-treated plants to two commercial fertilizers and tap water as a control.

Results

The heavy metal content of the GLF was below the maximum permissible concentrations (MPCs) for organic fertilizers as set out by the European Comission fertilizer regulation 1069/2009 and 1107/2009 (European Comission, 2019). However, despite having a fairly well-balanced nutrient content (0.1% N, 0.04% P₂O₅, and 0.2% K₂O), GLF had a negative effect on the growth, root weight, and yield of the tomato plants, killing six out of ten plants. GLF also promoted mold growth in the soil of some plants. Since the GLF was uncontaminated, heavy metal toxicity did not cause the negative effect.

Conclusions

Previous research showed that liquid fractions from some plants negatively affect the growth of others due to allelopathic chemicals; this, together with the stimulation of fungal growth, could have caused the negative effects observed. Future experiments will investigate the herbicidal property of GLF and possible treatments to potentially recover the nutrients contained within the GLF for application as a biofertilizer.     

Development and validation of a short questionnaire to assess sodium intake

OBJECTIVES: To develop and validate a short food-frequency questionnaire to assess habitual dietary salt intake in South Africans and to allow classification of individuals according to intakes above or below the maximum recommended intake of 6 g salt day-1. DESIGN: Cross-sectional validation study in 324 conveniently sampled men and women. METHODS: Repeated 24-hour urinary Na values and 24-hour dietary recalls were obtained on three occasions. Food items consumed by >5% of the sample and which contributed > or =50 mg Na serving-1 were included in the questionnaire in 42 categories. A scoring system was devised, based on Na content of one index food per category and frequency of consumption. RESULTS: Positive correlations were found between Na content of 35 of the 42 food categories in the questionnaire and total Na intake, calculated from 24-hour recall data. Total Na content of the questionnaire was associated with Na estimations from 24-hour recall data (r = 0.750; P < 0.0001; n = 328) and urinary Na (r = 0.152; P = 0.0105; n = 284). Urinary Na was higher for subjects in tertile 3 than tertile 1 of questionnaire Na content (P < 0.05). Questionnaire Na content of <2400 and > or =2400 mg day-1 equated to a reference cut-off score of 48 and corresponded to mean (standard deviation) urinary Na values of 145 (68) and 176 (99) mmol day-1, respectively (P < 0.05). Sensitivity and specificity against urinary Na > or =100 and <100 mmol day-1 was 12.4% and 93.9%, respectively. CONCLUSION: A 42-item food-frequency questionnaire has been shown to have content-, construct- and criterion-related validity, as well as internal consistency, with regard to categorising individuals according to their habitual salt intake; however, the devised scoring system needs to show improved sensitivity.