Localization of the succinate receptor in the distal nephron and its signaling in polarized MDCK cells

When the succinate receptor (SUCNR1) is activated in the afferent arterioles of the glomerulus it increases renin release and induces hypertension. To study its location in other nephron segments and its role in kidney function, we performed immunohistochemical analysis and found that SUCNR1 is located in the luminal membrane of macula densa cells of the juxtaglomerular apparatus in close proximity to renin-producing granular cells, the cortical thick ascending limb, and cortical and inner medullary collecting duct cells. In order to study its signaling, SUCNR1 was stably expressed in Madin-Darby Canine Kidney (MDCK) cells, where it localized to the apical membrane. Activation of the cells by succinate caused Gq and Gi-mediated intracellular calcium mobilization, transient phosphorylation of extracellular regulated kinase (ERK)1/2 and the release of arachidonic acid along with prostaglandins E2 and I2. Signaling was desensitized without receptor internalization but rapidly resensitized upon succinate removal. Immunohistochemical evidence of phosphorylated ERK1/2 was found in cortical collecting duct cells of wild type but not SUCNR1 knockout streptozotocin-induced diabetic mice, indicating in vivo relevance. Since urinary succinate concentrations in health and disease are in the activation range of the SUCNR1, this receptor can sense succinate in the luminal fluid. Our study suggests that changes in the luminal succinate concentration may regulate several aspects of renal function

Evidence of a sudden increase in α-chloralose poisoning in dogs and cats in the Netherlands between 2018 and 2021

BACKGROUND: After changes in European Union biocide legislation, the Dutch Poisons Information Center observed a strong increase in information requests concerning dogs and cats exposed to α-chloralose. To investigate whether α-chloralose-based rodenticides are safe for non-professional use, additional information regarding poisoning scenarios and clinical course was collected. METHODS: Veterinarians reporting α-chloralose exposure over a 2.5-year period were contacted by mail for follow-up information concerning exposure scenario, product formulation, clinical course and treatment, and outcome. In total, information was collected for 96 dogs and 41 cats. RESULTS: Fifty-three of 96 dogs and 17 of 19 cats known to have been exposed to α-chloralose-based rodenticides developed signs of central nervous system (CNS) depression or sensory-induced CNS excitation. Mortality in dogs and cats following exposure was 1% and 18%, respectively. An additional 22 cats presented with clinical signs suggestive of α-chloralose poisoning, with a mortality of 5%. LIMITATIONS: Exposure to α-chloralose was not confirmed by biochemical analyses. CONCLUSION: Dogs and especially cats were at risk of poisoning from α-chloralose. If criteria such as acute toxicity and risk of (secondary) poisoning are applied during the approval of α-chloralose-based rodenticides, similar to anticoagulant-based rodenticides, it can be concluded that α-chloralose is also not safe for non-professional use

Genomic Investigation of Two Acinetobacter baumannii Outbreaks in a Veterinary Intensive Care Unit in The Netherlands

Acinetobacter baumannii is a nosocomial pathogen that frequently causes healthcare-acquired infections. The global spread of multidrug-resistant (MDR) strains with its ability to survive in the environment for extended periods imposes a pressing public health threat. Two MDR A. baumannii outbreaks occurred in 2012 and 2014 in a companion animal intensive care unit (caICU) in the Netherlands. Whole-genome sequencing (WGS) was performed on dog clinical isolates (n = 6), environmental isolates (n = 5), and human reference strains (n = 3) to investigate if the isolates of the two outbreaks were related. All clinical isolates shared identical resistance phenotypes displaying multidrug resistance. Multi-locus Sequence Typing (MLST) revealed that all clinical isolates belonged to sequence type ST2. The core genome MLST (cgMLST) results confirmed that the isolates of the two outbreaks were not related. Comparative genome analysis showed that the outbreak isolates contained different gene contents, including mobile genetic elements associated with antimicrobial resistance genes (ARGs). The time-measured phylogenetic reconstruction revealed that the outbreak isolates diverged approximately 30 years before 2014. Our study shows the importance of WGS analyses combined with molecular clock investigations to reduce transmission of MDR A. baumannii infections in companion animal clinics

A New Family of Lysozyme Inhibitors Contributing to Lysozyme Tolerance in Gram-Negative Bacteria

Lysozymes are ancient and important components of the innate immune system of animals that hydrolyze peptidoglycan, the major bacterial cell wall polymer. Bacteria engaging in commensal or pathogenic interactions with an animal host have evolved various strategies to evade this bactericidal enzyme, one recently proposed strategy being the production of lysozyme inhibitors. We here report the discovery of a novel family of bacterial lysozyme inhibitors with widespread homologs in gram-negative bacteria. First, a lysozyme inhibitor was isolated by affinity chromatography from a periplasmic extract of Salmonella Enteritidis, identified by mass spectrometry and correspondingly designated as PliC (periplasmic lysozyme inhibitor of c-type lysozyme). A pliC knock-out mutant no longer produced lysozyme inhibitory activity and showed increased lysozyme sensitivity in the presence of the outer membrane permeabilizing protein lactoferrin. PliC lacks similarity with the previously described Escherichia coli lysozyme inhibitor Ivy, but is related to a group of proteins with a common conserved COG3895 domain, some of them predicted to be lipoproteins. No function has yet been assigned to these proteins, although they are widely spread among the Proteobacteria. We demonstrate that at least two representatives of this group, MliC (membrane bound lysozyme inhibitor of c-type lysozyme) of E. coli and Pseudomonas aeruginosa, also possess lysozyme inhibitory activity and confer increased lysozyme tolerance upon expression in E. coli. Interestingly, mliC of Salmonella Typhi was picked up earlier in a screen for genes induced during residence in macrophages, and knockout of mliC was shown to reduce macrophage survival of S. Typhi. Based on these observations, we suggest that the COG3895 domain is a common feature of a novel and widespread family of bacterial lysozyme inhibitors in gram-negative bacteria that may function as colonization or virulence factors in bacteria interacting with an animal host

Succinate receptors in the kidney

Contains fulltext : 98375.pdf (publisher's version ) (Closed access)The G protein-coupled succinate and alpha-ketoglutarate receptors are closely related to the family of P2Y purinoreceptors. Although the alpha-ketoglutarate receptor is almost exclusively expressed in the kidney, its function is unknown. In contrast, the succinate receptor, SUCRN1, is expressed in a variety of tissues, including blood cells, adipose tissue, liver, retina, and the kidney. Recent evidence suggests SUCRN1 and its succinate ligand are novel detectors of local stress, including ischemia, hypoxia, toxicity, and hyperglycemia. Local levels of succinate in the kidney also activate the renin-angiotensin system and together with SUCRN1 may play a key role in the development of hypertension and the complications of diabetes mellitus, metabolic disease, and liver damage. This makes the succinate receptor a promising drug target to counteract an expanding number of interrelated disorders

Evaluation of a virtual pet visit system with live video streaming of patient images over the Internet in a companion animal intensive care unit in the Netherlands

Objective To evaluate the impact of a virtual pet visit system (“TelePet” System, TPS) on owners and staff of a companion animal ICU. Design Longitudinal interventional study (2010–2013). Setting Companion animal ICU at a university veterinary medical teaching hospital. Study Populations Pet owners, ICU technicians. Interventions The introduction of the TPS, with live video streaming of patient images over the Internet, in a companion animal ICU. Measurements and Main Results Pet owners experienced TPS as a valuable extra service. Most TPS users (72.4%) experienced less anxiety and felt less need (40.4% of TPS users) to visit their hospitalized pet in person. Most users (83.5%) shared TPS access with their family. The introduction of the TPS did not improve overall owner satisfaction, except for the score on “quality of medical treatment.” Seven of 26 indicators of owner satisfaction were awarded higher scores by TPS users than by TPS nonusers in the survey after the introduction of the system. However, the lack of randomization of owners might have influenced findings. The enthusiasm of the ICU technicians for the system was tempered by the negative feedback from a small number of owners. Nevertheless they recognized the value of the system for owners. The system was user friendly and ICU staff and TPS users experienced few technical problems. Conclusions As veterinary healthcare is moving toward a more client-centered approach, a virtual pet visit system, such as TPS, is a relatively simple application that may improve the well-being of most owners during the hospitalization of their pet

Evaluation of a virtual pet visit system with live video streaming of patient images over the Internet in a companion animal intensive care unit in the Netherlands

Objective To evaluate the impact of a virtual pet visit system (“TelePet” System, TPS) on owners and staff of a companion animal ICU. Design Longitudinal interventional study (2010–2013). Setting Companion animal ICU at a university veterinary medical teaching hospital. Study Populations Pet owners, ICU technicians. Interventions The introduction of the TPS, with live video streaming of patient images over the Internet, in a companion animal ICU. Measurements and Main Results Pet owners experienced TPS as a valuable extra service. Most TPS users (72.4%) experienced less anxiety and felt less need (40.4% of TPS users) to visit their hospitalized pet in person. Most users (83.5%) shared TPS access with their family. The introduction of the TPS did not improve overall owner satisfaction, except for the score on “quality of medical treatment.” Seven of 26 indicators of owner satisfaction were awarded higher scores by TPS users than by TPS nonusers in the survey after the introduction of the system. However, the lack of randomization of owners might have influenced findings. The enthusiasm of the ICU technicians for the system was tempered by the negative feedback from a small number of owners. Nevertheless they recognized the value of the system for owners. The system was user friendly and ICU staff and TPS users experienced few technical problems. Conclusions As veterinary healthcare is moving toward a more client-centered approach, a virtual pet visit system, such as TPS, is a relatively simple application that may improve the well-being of most owners during the hospitalization of their pet

Evaluation of a veterinary triage list modified from a human five-point triage system in 485 dogs and cats

OBJECTIVES: To devise a veterinary triage list (VTL) and to determine whether the application of this VTL results in more accurate categorization of emergency patients compared with intuitive triage. DESIGN: Prospective and retrospective observational study. SETTING: Private veterinary emergency clinic. ANIMALS: Four hundred and eighty-five client-owned dogs and cats. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A VTL was composed using a human triage system and data from medical records of the study group. Target waiting times were prospectively determined using intuition by veterinary nurses (TWT-N).  Target waiting times were subsequently determined retrospectively by the use of the VTL (TWT-VTL).  Both TWT-N and TWT-VTL were compared against target waiting times determined by a review team (TWT-R), which was considered the gold standard. TWT categories included 0, 15, 30-60, and 120 minutes, and were associated with triage categories red, orange, yellow, and green, respectively. Differences in agreement were tested for significance. One hundred and eighty-five dogs and 300 cats fulfilled the inclusion criteria. TWT-N and TWT-R agreed on 30 cases of 67 (44.8%) in triage category red and 22 of 89 (24.7%) in category orange. TWT-VTL and TWT-R agreed on 64 cases of 67 (95.5%) in category red and 75 of 89 (84.3%) in category orange. Agreement between TWT-VTL and TWT-R (Pearson's R = 0.848) was significantly greater (P < 0.001) than agreement between TWT-N and TWT-R (Pearson's R = 0.519). CONCLUSIONS: Intuitive triage performed by veterinary nurses showed significantly less correlation with TWT-R than triage performed with the VTL. A short physical examination in all emergency patients appears to be essential in recognizing critical disease. The use of a standardized VTL can help to categorize veterinary emergency patients

Negative pressure therapy versus passive open abdominal drainage for the treatment of septic peritonitis in dogs : a randomized, prospective study

Objective: To compare passive open abdominal drainage (POAD) and negative-pressure abdominal drainage (NPAD) using the ABThera (TM) system in the treatment of septic peritonitis. Study design: Randomized prospective clinical trial. Animals: Dogs (n = 16) with septic peritonitis. Methods: Dogs with septic peritonitis were randomly assigned to one of two treatment protocols: NPAD versus POAD. Anesthesia time, operating time, duration of drainage, costs, survival, and complications were compared between techniques. Hematological and biochemical parameters in blood and abdominal fluid, and histopathological findings of omentum and abdominal wall tissue samples were compared between NPAD and POAD at time of initial surgery and at time of closure. Results: Overall survival was 81%. Treatment costs, anesthesia and operating time, drainage time, survival, and postoperative complications were similar between techniques. Loss of total plasma protein and decreased inflammation-related factors in abdominal fluid at time of closure were noted in all patients. Neutrophilic inflammation was greater in abdominal wall samples after NPAD. POAD patients showed discomfort during bandage changes and had frequent leakage of abdominal fluid outside of the bandage. Conclusion: NPAD is an effective alternative to POAD for treatment of septic peritonitis, based on costs and survival. NPAD resulted in less abdominal fluid leakage, and evidence of superior healing on histological evaluation of abdominal tissues