Can a renal nurse assess fluid status using ultrasound on the inferior vena cava? A cross-sectional interrater study: Ultrasound on the inferior vena cava

Introduction: Ultrasound of the inferior vena cava (IVC-US) has been used to estimate intravascular volume status and fluid removal during a hemodialysis session. Usually, renal nurses rely on other, imprecise methods to determine ultrafiltration. To date, no study has examined whether renal nurses can reliably perform ultrasound for volume assessment and for potential prevention of intradialytic hypotension. This pilot study aimed to determine if a renal nurse could master the skill of performing and correctly interpreting Point of Care Ultrasound on patients receiving hemodialysis. Methods: After receiving theoretical training and performing 100 training scans, a renal nurse performed 60 ultrasound scans on 10 patients. These were categorized by the nurse into hypovolemic, euvolemic, or hypervolemic through measurement of the maximal diameter and degree of collapse of the IVC. Scans were subsequently assessed for adequacy and quality by two sonologists, who were blinded to each other\u27s and the nurse\u27s results. Findings: The interrater reliability of 60 scans was good, with intraclass correlation 0.79 (95% confidence interval (CI) =0.63–0.87) and with a good interrater agreement for the following estimation of intravascular volume (Cohen\u27s weighted Kappa κw = 0.62), when comparing the nurse to an expert sonographer. Discussion: A renal nurse can reliably perform ultrasound of the IVC in hemodialysis patients, obtaining high quality scans for volume assessment of hemodialysis patients. This novel approach could be more routinely applied by other renal nurses to obtain objective measures of patient volume status in the dialysis setting

<i>Drosophila melanogaster</i> female reproductive tract.

<p>Mature oocytes leave the ovary and move through the oviducts to reach the uterus, where they can be fertilized prior to being laid. Sperm are stored in specialized organs (spermathecae, seminal receptacle; see inset for higher magnification) that open into the uterus near the site where fertilization will occur. Activity of the spermathecal secretory cells (SSCs) plays important roles in gamete dynamics within the female <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001191#pbio.1001191-Schnakenberg1" target="_blank">[14]</a>. The inset also shows the female accessory glands (also called parovaria), which are believed to have a secretory function but are not sites of sperm storage. Drawing by J. L. Sitnik.</p

Processing of SFPs is defective in the absence of seminase.

<p>(A) Western blot probed with ovulin antibody. Lane 1: full-length ovulin in male accessory glands (AG). Lanes 2–9: female reproductive tracts (RT) dissected after mating to control (+) or RNAi (−) males for the gene given above the lanes. Females were dissected at 45 minutes after the start of mating (ASM) (lanes 2–5) or 2 hours ASM (lanes 6–9). All lanes are from the same gel with extraneous lanes removed for clarity. (B) Western blot probed with ovulin antibody. All lanes are female RT dissected at 30 minutes ASM. Lanes 1 and 2 are from females mated to seminase control (+) or RNAi (−) males. Lanes 3 and 4 are from females mated to CG10587 control (+) or RNAi (−) males. (C) Western blot probed with Acp36DE antibody. All lanes are from the same gel, with extraneous lanes cut out for clarity. Lanes 1–8 contain RT from females mated to males of the given genotype as in (A). Females were dissected at 1 hour ASM (lanes 2–5) or 3 hours ASM (lanes 6–9). Un-processed (full-length) Acp36DE runs at ∼122 kDa. (D) Western blot probed with CG11864 antibody. Female RTs dissected at 45 minutes ASM to seminase control (lane 1) or knockdown (lane 2) males. Numbers to the left of blots indicate approximate band size in kDa.</p

Heredity Dryad averaged data submission

This data is line averages for several traits measured for this manuscript. It was used for all the analysis described in the manuscript apart from the relationship between female size and number of eggs laid by females

Females mated to seminase knockdown males retain more sperm 4 and 10 days after mating.

<p>Sperm counts for seminase line 1 are shown for sperm stored at three timepoints after mating, as given on the x-axis. Line 2 yielded similar results. Asterisks indicate level of significance (*p<0.05; **p<0.01). (A) Total average number of sperm stored in both storage organs (2 h: t = −0.09, p = 0.93; 4 d: t = −1.6, p = 0.13; 10 d: t = −3.2, p<0.01). (B) Average number of sperm stored in the seminal receptacle only (2 h: t = −0.06, p = 0.96; 4 d: t = −2.8, p<0.01; 10 d: t = −3.2, p<0.01). (C) Average number of sperm stored in the paired spermathecae only; numbers are the sum of sperm stored in each spermatheca (2 h: t = −0.11, p = 0.91; 4 d: t = 2.2, p<0.05; 10 d: t = −1.1, p = 0.26). Samples sizes are, for bars from left to right: (A) 12, 14, 16, 10, 7, 15; (B) 17, 21, 18, 19, 7, 15; (C) 13, 14, 19, 10, 7, 15. Abbreviations: 2 h, 2 hours; 4 d, four days; 10 d, 10 days. Error bars indicate standard error.</p

Female receptivity to second mating.

<p>Females were mated first to control or RNAi knockdown males from the line shown (either seminase line 1 or 2, or CG4815). CG4815 is included as a control for the VDRC strain background. The time given is the number of days after the first mating that the second mating was attempted. Females who remated to a male from a wildtype strain (Canton-S) during a one hour observation period are shown as a percentage with the total number of potential mating pairs assayed in brackets. P values in bold are significant.</p

Heredity Dryad eggs laid data submission

These data were used in the analysis investigating the relationship between female size and the number of eggs laid by females

Seminase is required for two post-mating pathways.

<p>Seminase is cleaved during mating within the male reproductive tract where it is required for CG11864 cleavage. CG11864 then regulates processing of two SFPs, ovulin and Acp36DE (left branch). Seminase is also necessary for the long term response (LTR) pathway (right branch). Proteins/pathways downstream of seminase are involved in the processes shown in boxes, based on earlier knockout or knockdown studies. The consequences of proteolytic processing of ovulin and Acp36DE remain unknown.</p

Seminase is produced in the accessory glands and is processed during and after mating.

<p>(A) Western blot probed with seminase antibody. Seminase in the male accessory glands (AG) has an apparent molecular weight of ∼29-kDa. No seminase was detected in testes (T), the ejaculatory duct and bulb (ED/EB), or in virgin female reproductive tracts. AG and T: tissue from 10 virgin males. ED/EB: tissue from 20 virgin males. Female: tissue from 4 virgin females. Tubulin is shown as a loading control. Total protein loaded is shown in micrograms as measured by BCA assay. (B) Western blot probed with seminase antibody. Lane 1: full-length seminase in AG. Lane 2: ED/EB dissected from 20 males at 8–10 minutes ASM. Lane 3: Reproductive tracts (RT) from 20 females dissected 8–10 minutes ASM. Lanes 4–8: Female RTs dissected at the times ASM indicated above the lanes. (C) Western blots probed for seminase (top) and ovulin (bottom). Lane 1: full length protein in AG. Lanes 2 and 3: RT from females mated to CG11864 control (+) or knockdown (−) males at 1 hour ASM.</p

Females mated to seminase knockdown males lay fewer eggs.

<p>(A) The average number of eggs laid per female in a given treatment over 10 days. Seminase Line 1: Control N = 55, RNAi N = 59; CG4815: Control N = 20, RNAi N = 18. (B) Hatchability data for the corresponding experiments in (A). Hatchability is defined as the proportion of eggs that yielded adult progeny. CG4815 (a serine protease SFP) is included as a control for strain background. (A),(B) Asterisks indicate p<0.0001. (C) The data from (A) plotted as average number of eggs laid by females in each group on individual days of the experiment. (D) CG4815 egg laying data plotted as in (C). Asterisks indicate level of significance after Bonferroni correction (*p<0.05, **p<0.01, ***p<0.0001). Error bars indicate standard error of the raw data pooled over experiments.</p