Inferring an animal's environment through biologging: quantifying the environmental influence on animal movement.

BACKGROUND: Animals respond to environmental variation by changing their movement in a multifaceted way. Recent advancements in biologging increasingly allow for detailed measurements of the multifaceted nature of movement, from descriptors of animal movement trajectories (e.g., using GPS) to descriptors of body part movements (e.g., using tri-axial accelerometers). Because this multivariate richness of movement data complicates inference on the environmental influence on animal movement, studies generally use simplified movement descriptors in statistical analyses. However, doing so limits the inference on the environmental influence on movement, as this requires that the multivariate richness of movement data can be fully considered in an analysis. METHODS: We propose a data-driven analytic framework, based on existing methods, to quantify the environmental influence on animal movement that can accommodate the multifaceted nature of animal movement. Instead of fitting a simplified movement descriptor to a suite of environmental variables, our proposed framework centres on predicting an environmental variable from the full set of multivariate movement data. The measure of fit of this prediction is taken to be the metric that quantifies how much of the environmental variation relates to the multivariate variation in animal movement. We demonstrate the usefulness of this framework through a case study about the influence of grass availability and time since milking on cow movements using machine learning algorithms. RESULTS: We show that on a one-hour timescale 37% of the variation in grass availability and 33% of time since milking influenced cow movements. Grass availability mostly influenced the cows' neck movement during grazing, while time since milking mostly influenced the movement through the landscape and the shared variation of accelerometer and GPS data (e.g., activity patterns). Furthermore, this framework proved to be insensitive to spurious correlations between environmental variables in quantifying the influence on animal movement. CONCLUSIONS: Not only is our proposed framework well-suited to study the environmental influence on animal movement; we argue that it can also be applied in any field that uses multivariate biologging data, e.g., animal physiology, to study the relationships between animals and their environment. SUPPLEMENTARY INFORMATION: Supplementary information accompanies this paper at 10.1186/s40462-020-00228-4.

Low essential fatty acid and B-vitamin status in a subgroup of patients with schizophrenia and its response to dietary supplementation.

We assessed essential fatty acid (EFA) and B-vitamin status, together with their determinants, in 61 patients with schizophrenia and established whether those with poor status responded biochemically to the appropriate dietary supplements. As a group, the patients had high erythrocyte saturated fatty acids (FAs), monounsaturated FA and low polyunsaturated FA of the omega3 and omega6 series. Patients reporting not to take vitamin supplements had low vitamin B12 and high homocysteine. Homocysteine variance proved best explained by folate in both the total group and male patients, and by vitamins B12 and B6 in females. Alcohol consumption and duration of illness are risk factors for low polyunsaturated FA status (< P2.5 of reference range), while male gender and absence of fish consumption predict hyperhomocysteinemia (> P97.5 of reference range). Two patients exhibited biochemical EFA deficiency and seven showed biochemical signs of omega3/docosahexaenoic acid (DHA) marginality. Four patients exhibited moderate hyperhomocysteinemia with plasma values ranging from 57.5 to 74.8 micromol/L. None of the five patients with either moderate hyperhomocysteinemia, biochemical EFA deficiency, or both, was predicted by their clinicians to have poor diets. That diet was nevertheless at the basis of these abnormalities became confirmed after supplementing 4 of them with B vitamins and with soybean and fish oils. We conclude that a subgroup of patients with schizophrenia has biochemical EFA deficiency, omega3/DHA marginality, moderate hyperhomocysteinemia, or combinations. Correction seems indicated in view of the possible relation of poor EFA and B-vitamin status with some of their psychiatric symptoms, but notably to reduce their high risk of cardiovascular disease.

[Esophageal rupture with aortic-esophageal fistula due to ingestion of foil packaged drugs]. / Oesofagusruptuur met aorto-oesofageale fistel door ingestie van medicatieverpakking.

A 78-year-old man was admitted because of haematemesis. A week before, the patient was admitted for prostate resection. During that admission he ingested an analgesic tablet complete with foil packaging. Since then, he suffered from dysphagia. Endoscopic examination revealed the foil packaging, but during the procedure massive bleeding in the oesophagus occurred. Despite initial haemodynamic stabilisation, fatal bleeding occurred a short while later. Post mortem examination revealed an aortic-oesophageal fistula which was ascribed to the foil packaging. One other oesophageal rupture was thought to be due to the packaging and a third rupture was ascribed to the inserted Sengstaken-Blakemore tube. Ingestion of a foil packaging warrants active medical intervention, as is stated elsewhere in the literature.

Oral immunisation of naive and primed animals with transgenic potato tubers expressing LT-B.

The efficacy of edible vaccines produced in potato tubers was examined in mice. Transgenic plants were developed by Agrobacterium tumefaciens-mediated transformation. The antigen selected was the non-toxic B subunit of the Escherichia coli enterotoxin (recLT-B). A synthetic gene coding for recLT-B was made and optimised for expression in potato tubers and accumulation in the endoplasmic reticulum. Introduction of this gene under control of the tuber-specific patatin promoter in potato plants resulted in the production of functional, i.e. Gm1-binding, recLT-B pentamers in tubers. Selected tubers containing about 13 microg of recLT-B per gram fresh weight were used for immunisation. Subcutaneous immunisation with an extract of recLT-B tubers yielded high antibody titres in serum that were similar to those obtained with bacterial recLT-B. The efficacy of oral administration of recLT-B tubers was determined by measuring mucosal and systemic immune responses in naive and primed mice. Animals were primed by subcutaneous injection of an extract of recLT-B tuber plus adjuvant. Naive and primed mice were fed 5 g of tubers ( approximately 65 microg of recLT-B) or were intubated intragastrically with 0.4 ml of tuber extract ( approximately 2 microg of recLT-B). In naive mice, feeding recLT-B tubers or intubation of tuber extract did not induce detectable anti-LT antibody titres. In primed animals, however, oral immunisation resulted in significant anti-LT IgA antibody responses in serum and faeces. Intragastric intubation of tuber extract revealed higher responses than feeding of tubers. These results indicate clearly that functional recLT-B can be produced in potato tubers, that this recombinant protein is immunogenic and that oral administration thereof elicits both systemic and local IgA responses in parentally primed, but not naive, animals.

Optimization of daily folate, vitamin B12 and vitamin B6 supplements in paediatric patients with sickle cell disease

We determined optimal folate, vitamin B12 and vitamin B6 dosages in 21 sickle cell disease (SCD) patients (11 HbSS, 10 HbSC; mean 7 years, range 7-16), using plasma homocysteine (Hcy) as functional marker. They received daily 400 g (0-3 weeks), 700 g (3-6) and 1000 g (6-70) folate; 1 (0-21), 3 (21-45 and 5 RDA (45-70) vitamin B12; and 1 RDA vitamin B6 (0-70). Blood was taken at baseline (P0) and after 3 (PI), 6 (P2), 9 (P3), 21 (P4), 33 (P5), 45 (P6), 57 (P7) and 70 (P8) weeks for measurement of erythrocyte (RBC), serum folate, plasma vitamin B12, whole blood vitamin B6 and plasma Hcy. Vitamin B6 increased from P0 to P1 and P1 to P2; vitamin B12 from P4 to P8; serum folate from P0 to P1 and P1 to P2; RBC folate from P0 to P1, P1 to P2 and P2 to P3. Hcy decreased from P1 to P2 and P4 to P6. Most pronounced Hcy decreases occurred from P0 to P1 (43 percent of patients), P1 to P2 (14 percent) and P4 to P5 (24 percent). Haematological indices did not change. Patients with HbSS had higher RBC folate at P1, P2 and P8. The entire group exhibited inverse relations between RBC folate and haemoglobin on P1, P2, P3, P6, P7 and P8. We conclude that RBC folate is less valuable for folate status assessment in SCD patients. The optimal daily supplement is 700 g folate (3.5-7 RDA vitamin B12 (4.2-6.0 g) and 1 RDA vitamin B6 (1.4-2.0 mg). This combination causes Hcy levels that do not decrease further upon higher dosages and may reduce by simple and relatively inexpensive means their inherently high risk of endothelial damage.(Au)

Striatal dopamine-glutamate interactions reflected in substantia nigra reticulata firing.

To gain insight into the role of striatal dopamine in basal ganglia functioning, dopaminergic drugs alone and in combination with the glutamate receptor agonist kainic acid were infused in the lateral striatum via a microdialysis probe, while single-unit recordings of substantia nigra reticulata neurons were made in chloral hydrate-anaesthetized rats. Striatal infusion of dopaminergic drugs did not significantly affect the firing rate of substantia nigra reticulata neurons, which was related to the low activity of striatal cells under basal conditions, illustrated by the lack of effect of striatal infusion of TTX on substantia nigra reticulata activity. Under glutamate-stimulated conditions, striatal infusion of d-amphetamine potentiated the inhibition of substantia nigra reticulata neurons induced by striatal kainic acid. Thus, under stimulated but not basal conditions, the modulatory role of dopamine in the striatum could be demonstrated. Dopamine potentiated the inhibitory effect of striatal kainic acid on the firing rate of the basal ganglia output neurons.

A new ELISA for the detection of anti-heparan sulfate reactivity, using photobiotinylated antigen.

Autoantibodies reacting with a great variety of autoantigens are characteristic for the autoimmune disease systemic lupus erythematosus (SLE). Although reactivity with heparan sulfate (HS) in sera of patients with SLE is found in association with the occurrence of nephritis, the aetiological significance of this association is not clear. The assay which is generally used to measure anti-HS reactivity is subject to false-positive results, as a consequence of the binding of negatively charged moieties within immune complexes to the precoat employed (protamine sulfate). Therefore, we have developed a new ELISA in which photobiotinylated HS is efficiently and reproducibly bound to streptavidin-coated wells. We compared the new ELISA with the classical anti-HS ELISA by testing culture supernatants of 20 murine monoclonal antibodies (mAb) to DNA (containing free anti-DNA and anti-DNA/nucleosome immune complexes) and preparations of these mAb (containing only free anti-DNA), purified under dissociating conditions. In the classical anti-HS ELISA, 14 out of 20 of the culture supernatants reacted positively with HS; after purification no reactivity remained. The discrepancy must be due to anti-DNA/nucleosome immune complexes present in the culture supernatants. In the new ELISA only four out of 20 culture supernatants and one of the purified preparations reacted with HS. This latter reactivity is probably not specific, since this mAb also reacted with streptavidin alone. To find out whether there is a correlation between the occurrence of nephritis and anti-HS reactivity, measured in this new anti-HS ELISA, we tested sera of patients with a renal- or non-renal exacerbation of SLE in the newly developed anti-HS ELISA. We observed a correlation between anti-HS reactivity and nephritis.

Treatment of chronic bacterial prostatitis with ciprofloxacin.

Thirty two patients with proven chronic bacterial prostatitis were treated with ciprofloxacin 500 mg twice daily orally for four weeks. The causative organisms, cultured from prostatic fluid were Enterobacteriaceae (19 patients), enterococci (9), staphylococci (4), streptococci (3), non-fermentative Gram-negative rods (2) and anaerobic bacteria (9). Nineteen patients had pure cultures, 13 mixed cultures. The susceptibility of all organisms to ciprofloxacin, sulfamethoxazole, trimethoprim and doxycyclin was determined by agar dilution. The effect of therapy was measured by clinical parameters and by repeated cultures of prostatic fluid during and after therapy up to six months. Clinical cure (at one month after therapy) was obtained in 22 patients, improvement in seven; two patients did not respond, one patient had to stop during therapy because of severe nausea. No other side effects were noted. Ciprofloxacin may be a useful alternative drug in the treatment of prostatitis.

Intraprostatic concentration of ciprofloxacin and its activity against urinary pathogens.

The in-vitro activity of ciprofloxacin against 376 urinary pathogens was determined. The minimal inhibitory concentrations for 90% of the Enterobacteriaceae were 0.03-0.23 mg/l, for Pseudomonas aeruginosa 0.37 mg/l, for Streptococcus faecalis 0.75 mg/l and for Staphylococcus aureus 0.92 mg/l. A 100 mg dose of ciprofloxacin was administered intravenously to 25 patients undergoing prostatectomy. The concentrations in prostate and serum were measured at different intervals. Peak levels in prostate were 3.0 micrograms/g attained 20 min after administration. Peak serum levels were 1.2 mg/l attained 20 min after administration. Serum and prostate elimination was slowly. The overall serum: prostate ratio 1:2.1.