In-orchard population dynamics of Erwinia amylovora on apple flower stigmas

Populations of the fire blight pathogen Erwinia amylovora Ea110 on apple flower stigmas were tracked over the course of apple bloom in field studies conducted between 2016 and 2019. In 18 of 23 experiments, flower stigmas inoculated on the 1st day of opening were found to harbor large (106-107 cells / flower) populations of E. amylovora when assessed three to five days post-inoculation. However, populations inoculated on stigmas of flowers that were already open for three days did not reach 106 cells / flower, and populations inoculated on stigmas of flowers that were already open for five days never exceeded 104 cells / flower. During this study, >10-fold increases in E. amylovora stigma populations in a 24-hr time period (termed population surges) were observed on 34.8%, 20.0%, and 4.0% of possible days on 1-day, 3-day, and 5-day open flowers, respectively. Population surges occurred on days with average temperatures as high as 24.5°C and as low as 6.1°C. Experiments incorporating more frequent sampling during days and overnight revealed that many population surges occurred between 10:00 PM and 2:00 AM. A Pearson’s correlation analysis of weather parameters occurring during surge events indicated that population surges were significantly associated with situations where overnight temperatures either increased or remained constant, where wind speed decreased, and where relative humidity increased. This study refines our knowledge of E. amylovora population dynamics and further indicates that E. amylovora is able to infect flowers during exposure to colder field temperatures than previously reported.

Utility of Visual Analog Scale of Subdomain Scores of the 22-Item Sinonasal Outcome Test in Chronic Rhinosinusitis

The burden of chronic rhinosinusitis (CRS) symptomatology is frequently measured with the 22-item Sinonasal Outcome Test (SNOT-22). In some situations, such as when there is need for frequent sampling, a full SNOT-22 may be impractical, and an abbreviated measure may be useful. Herein, we study 4 questions reflecting the 4 SNOT-22 subdomains as accurate reflections of SNOT-22 content. In total, 250 patients with CRS completed a SNOT-22 and answered 4 questions about their total nasal symptoms, poor sleep quality, ear/facial pain, and mood (reflecting SNOT-22 subdomains) using visual analog scales (VASs). The 4 SNOT-22 subdomain VAS scores each correlated strongly with the corresponding SNOT-22 subdomain scores. The sum of the 4 subdomain question VAS scores was highly correlated with the total SNOT-22 score ( r = 0.77, P < .001). This preliminary study suggests information from the SNOT-22 may be ascertained through 4 questions reflecting the 4 SNOT-22 subdomains, although further validation is needed.

Toward precision oncology: SERS microfluidic systems for multiplex biomarker analysis in liquid biopsy

Liquid biopsy-based diagnosis in precision oncology exhibits significant advantages over the traditional tumour biopsies by offering dynamic assessment of tumour heterogeneity, minimally invasive procedures for frequent sampling, and cost-effective tests....

PSI-2 A procedure for urine collection in pre-weaned heifer calves

Urine collection is a useful tool to analyze intestinal permeability in cattle for research and diagnostic purposes. However, urine sampling techniques often rely on total waste collection, which reduces the ability to perform more frequent sampling and obtain accurate and sterile urine volumes. A potential alternative is urethral catheters, which have been used in cows and weaned heifers. However, urethral catheters have not been thoroughly tested in pre-weaned dairy heifer calves. The study objective was to develop a urethral catheter placement procedure in pre-weaned heifer calves for continuous and accurate urine collection. Fifteen Holstein heifer calves had catheters placed at 8 ± 2 days (37.5 ± 3.38 kg BW) and 40 ± 2 days (59.3 ± 5.38 kg BW) of age. During the procedure, calves were individually housed (1.87 m2/calf) and restrained. The vulva was cleaned using betadine and 70% ethanol and then a sterile, lubricated 8.9 cm speculum was inserted into the vagina. A sterile guidewire (145 cm x 0.89 cm) was inserted into a lubricated sterile 10 FR catheter. The catheter was inserted into the urethral opening (~5–7 cm into vagina), guided into the bladder, and the catheter balloon was filled with water (10 mL). The guide wire was removed, and urine flow confirmed correct placement before a 4 L urinary drainage bag was attached to the catheter. Individual calf health observations were made twice over a 24-hour period and included vaginal discharge, bleeding, redness or inflammation, and tissue discharge in the urine. Occurrence rate was determined using PROC FREQ in SAS 9.4. Regardless of catheterization timing, bleeding and tissue discharge occurred at a rate of 3.33% ± 0.18, and vaginal discharge and inflammation occurred at a rate of 6.70% ± 0.25. In summary, this procedure is a viable method for total urine collection in pre-weaning heifer calves.

Establishment of Gut Microbiome During Early Life and Its Relationship With Growth in Endangered Crested Ibis (Nipponia nippon)

Gut microbiota during early life could influence host fitness in vertebrates. Studies on how gut microbiota colonize the gut in birds using frequent sampling during early developmental stages and how shifts in microbiota diversity influence host growth are lacking. Here, we examine the microbiome profiles of 151 fecal samples from 14 young crested ibis (Nipponia nippon), an endangered bird species, collected longitudinally across 13 time points during the early stages of development and investigated their correlation with host growth. Gut diversity showed a non-linear change during development, which involved multiple colonization and extinction events, mainly associated with Proteobacteria and Firmicutes. Gut microbiota in young crested ibis became more similar with increasing age. In addition, gut microbiota exhibited a strong temporal structure and two specific developmental stages; the beginning of the latter stage coincided with the introduction of fresh loach, with a considerable increase in the relative abundance of Fusobacteria and several Firmicutes, which may be involved in lipid metabolism. Crested ibis chick growth rate was negatively correlated with gut microbiota diversity and negatively associated with the abundance of Halomonadaceae, Streptococci, Corynebacteriaceae, and Dietziaceae. Our findings highlight the importance of frequent sampling when studying microbiome development during early stages of development of vertebrates. The role of microbial diversity in host growth during the early stages of development of birds warrants further investigations.

757 Does Increased Sampling of Cerebrospinal Fluid from External Ventricular Drains Lead to Increased Rates of Infection?

Introduction External ventricular drains (EVDs) are commonly used in the management of acute hydrocephalus after subarachnoid haemorrhage (SAH). Infection is the most common complication. There remains controversy over whether frequent sampling is associated with increased risk of infection. Method Two cohorts of patients requiring EVD after SAH were retrospectively analysed for suspected and proven CSF infection. The first clinical cohort was of 50 consecutive patients with twice weekly sampling. The second group had alternate daily sampling as part of a prospective research study. Results Female to male ratio were (32:18) and (29:15) in clinical vs research group respectively. Average age of both groups was 59. Average length of treatment with EVD in both groups was 10 days. 16/50 (32%) patients had a suspected infection vs 13/44 (30%) and 8/50 (16%) had a proven infection compared to 6/44 (14%) in clinical and research groups, respectively. There was no statistically significant difference between the two groups (suspected infections p = 0.7 and proven infections p = 0.7) Conclusions Increased rates in CSF sampling in the research cohort did not result in higher rates of CSF infection. This suggests that rate of sampling, if done following a strict protocol, is not associated with increased risk of infection.

Serum Concentrations of GDF9 and BMP15 Across the Menstrual Cycle

Growth differentiation factor-9 (GDF9) and bone morphogenetic protein-15 (BMP15) are TGF-β proteins that regulate key processes throughout folliculogenesis and are determinants of mammalian fecundity (1). They are uniquely produced predominantly by the oocyte and have potential clinical application as markers of oocyte quality and quantity (2). However, no studies have been conducted to assess whether serum concentrations alter across the different phases of the menstrual cycle, and thus if assessment should be confined to specific cycle stages. The aim of this study was to measure serum concentrations of these proteins during the menstrual cycle in women at different stages of reproductive life. Serum was collected every 1-3 days throughout the menstrual cycle from 41 healthy ovulatory women from three cohorts: menses to late luteal phase (21-29 years of age; n=16; University of Otago) and across one interovulatory interval (18-35 years of age; n=10; and 45-50 years of age; n=15; University of Saskatchewan), with simultaneous ultrasound scans confirming ovulation. Serum concentrations of GDF9, BMP15, estradiol, FSH, LH, progesterone, inhibin A and B and AMH were measured. GDF9 and BMP15 were detectable in 54% and 73% of women and varied 236- and 52-fold between women, respectively. To detect changes, mean concentrations and variances across the cycle were statistically modelled using a generalized additive model of location, shape and scale (GAMLSS). Across the menstrual cycle, there were minimal changes in serum GDF9 or BMP15 within a woman for all cohorts, with no significant differences detected in modelled mean concentrations. However, modelled variances were highest in the luteal phases of all women for BMP15 immediately following ovulation, regardless of age, suggesting a possible underlying cyclic pattern. These results suggest that serum BMP15 and GDF9 are not overtly affected by menstrual cycle dynamics but may be more stable in the follicular phase. Larger studies with more frequent sampling should establish if BMP15 and presumably GDF9 demonstrate clinically relevant cyclic variation. References: (1) Gilchrist RB et al., HRU 2008; 14:159-77. (2) Riepsamen AH et al., Endocrinol 2019; 160:2298-313.

Assessment of the Advanced Very High-Resolution Radiometer (AVHRR) for Snowfall Retrieval in High Latitudes Using CloudSat and Machine Learning

Precipitation retrieval is a challenging topic, especially in high latitudes (HL), and current precipitation products face ample challenges over these regions. This study investigates the potential of the Advanced Very High-Resolution Radiometer (AVHRR) for snowfall retrieval in HL using CloudSat radar information and machine learning (ML). With all the known limitations, AVHRR observations should be considered for HL snowfall retrieval because (1) AVHRR data have been continuously collected for about four decades on multiple platforms with global coverage, and similar observations will likely continue in the future; (2) current passive microwave satellite precipitation products have several issues over snow and ice surfaces; and (3) good coincident observations between AVHRR and CloudSat are available for training ML algorithms. Using ML, snowfall rate was retrieved from AVHRR’s brightness temperature and cloud probability, as well as auxiliary information provided by numerical reanalysis. The results indicate that the ML-based retrieval algorithm is capable of detection and estimation of snowfall with comparable or better statistical scores than those obtained from the Atmospheric Infrared Sounder (AIRS) and two passive microwave sensors contributing to the Global Precipitation Measurement (GPM) mission constellation. The outcomes also suggest that AVHRR-based snowfall retrievals are spatially and temporally reasonable and can be considered as a quantitatively useful input to the merged precipitation products that require frequent sampling or long-term records.

Time-lag of urinary and salivary cortisol response after a psychological stressor in bonobos (Pan paniscus)

Cortisol is often measured as a marker for stress. Therefore, a profound validation of the time-lag between the stressor and the increase and peak in cortisol levels is needed. No study measured both the urinary and salivary cortisol time-lag after a psychological stressor. In this study, we used a frequent sampling study design to (1) describe the urinary and salivary cortisol pattern during a control day; and (2) characterize the induced excretion pattern of urinary and salivary cortisol after a psychological stressor in six zoo-housed bonobos. Liquid chromatography-tandem mass spectrometry was used to analyze 71 urine and 162 saliva samples collected on a control and a test day. We found that the time-lag between the stressor and the maximal cortisol concentration was similar in urine and saliva (160 min after the stressor). However, salivary cortisol after the stressor did show a faster and steeper increase than urinary cortisol. We also show inter-individual variation in the baseline and stress levels of cortisol, which should be considered in future cortisol studies. Our research highlights the importance of validation studies to confirm relevant sampling windows for cortisol sampling in order to obtain biologically meaningful results.

New Approach to the Assessment of Insecticide Losses from Paddy Fields Based on Frequent Sampling Post Application

High concentration of insecticides may appear in waters surrounding paddy fields shortly after application. Capturing the dynamic feature of this insecticide pulse may help control insecticide load to receiving waters. Based on continuous monitoring of the drainage process and two monitoring campaigns of three insecticides—chlorpyrifos, abamectin and thiamethoxam—in a paddy, this study examined the pattern of insecticide concentrations at different locations of paddy waters during the period of insecticide application accompanied with pest-control irrigation, and analyzed the factors affecting the environmental behavior of these insecticides. The results showed that the pulse-type drainage exhibited the following features: short duration (normally less than 1 d), large flow rate (as large as 4 L s−1), frequent occurrence (20 times during a 40-d period) and long time interval (as long as 5 d). Concentrations of the insecticides with higher Henry’s constant and vapor pressure peaked quickly (within several hours) post application in the field ditch; more than half of chlorpyrifos and abamectin loads were detected within merely 1 h after application. The high insecticide concentrations in the ditch were partly attributed to the primary and secondary drift. Moreover, a new kinetic model was proposed to describe the behavior of chlorpyrifos at the field edge. It is recommended that controlled drainage be implemented for at least 1 d post application to prevent the loss of insecticides. Findings from this study may provide new insights into insecticide behavior in the paddy environment for preventing adverse environmental impacts.