Sex hormone dose escalation for treating abnormal sleep in ovariectomized rats: in vitro GABA synthesis in sleep-related brain areas.

No data in the literature have evaluated sex hormone dose escalation for treating abnormal sleep of ovariectomized rats-nor studies on the role of sex hormones in GABA synthesis of rats' sleep-related areas. The main aim of this study was to determine the maximum tolerated dose (MTD) of estradiol (ET), progesterone (PT), and the mixture of both (EPT) to restore normal sleep in a model of menopause in rats. The second purpose was to describe the in vitro activity of glutamate decarboxylase (GAD) in sleep-related brain areas in the presence or absence of sex hormones. A weekly dose-escalation design of ET, PT, or EPT was implemented in ovariectomized rats (six per group). Dose escalation continued until the dose at which 100% of the rats exhibited a state of "complete somnolence." Doses that were not toxic or did not show side effects were considered. For in vitro experiments, sleep-related brain areas were separated and incubated with radiolabeled glutamate. Estradiol (17ß-E2), progesterone (P), and pyridoxal phosphate (PLP) were added to this assay, and GAD activity was determined. Under the same conditions, a second test was carried out, but the P antagonist RU486 was added to assess the role of P in GAD activity. Ovariectomy increased periodic awakenings compared to those determined for the SHAM group. The EPT for ovariectomized rats was very effective by the fifth week in decreasing arousal and achieving a similar sleep behavior to the SHAM-control group. Rats tolerated the ET, PT, and EPT well to the maximum planned dose (0.66 mg/kg and 4.4 mg/kg, respectively). No lethal events occurred; the MTD was reached. The in vitro studies indicated that the presence of 17ß-E2 plus P in the assay triggered the activity of isotype 65 GAD in all the studied brain areas. RU486 in the incubation medium blocked such activity; however, the action of isotype 67 GAD was not blocked by RU486. A dose-escalation model was determined; the MTD coincided with the maximum dose of ET and PT used. However, the EPT combination restored normal sleep in the menopause model compared to the SHAMs without toxic effects. The in vitro model demonstrated that 17ß-E2 plus P presence in the assay increased the activity of GAD65 in the studied brain tissues.

Physiological status of House Sparrows (Passer domesticus) along an ozone pollution gradient.

Mexico City is one of the most polluted cities in the world, and one in which air contamination is considered a public health threat. Numerous studies have related high concentrations of particulate matter and ozone to several respiratory and cardiovascular diseases and a higher human mortality risk. However, almost all of those studies have focused on human health outcomes, and the effects of anthropogenic air pollution on wildlife species is still poorly understood. In this study, we investigated the impacts of air pollution in the Mexico City Metropolitan Area (MCMA) on house sparrows (Passer domesticus). We assessed two physiological responses commonly used as biomarkers: stress response (the corticosterone concentration in feathers), and constitutive innate immune response (the concentration of both natural antibodies and lytic complement proteins), which are non-invasive techniques. We found a negative relationship between the ozone concentration and the natural antibodies response (p = 0.003). However, no relationship was found between the ozone concentration and the stress response or the complement system activity (p > 0.05). These results suggest that ozone concentrations in air pollution within MCMA may constrain the natural antibody response in the immune system of house sparrows. Our study shows, for the first time, the potential impact of ozone pollution on a wild species in the MCMA presenting the Nabs activity and the house sparrow as suitable indicators to assess the effect of air contamination on the songbirds.

A single-cohort retrospective analysis of factors associated with morbidity and mortality in 193 anesthetized domestic goats.

OBJECTIVE: To define the morbidity and mortality rates in goats undergoing general anesthesia at a large animal teaching hospital. STUDY DESIGN: Retrospective, single-cohort, observational study. ANIMALS: Records of 193 client-owned goats. METHODS: Data were collected from 218 medical records on 193 goats undergoing general anesthesia between January 2017 and December 2021. Demographic data, anesthetic management, recovery period and perianesthetic complications were recorded. Perianesthetic death was defined as anesthesia-related or anesthesia-contributory death occurring within 72 hours after recovery. Records of goats that were euthanized were reviewed to ascertain the cause of euthanasia. Each explanatory variable was individually investigated by univariable penalized maximum likelihood logistic regression, followed by multivariable analysis. Statistical significance was set at p < 0.05. RESULTS: Perianesthetic mortality was 7.3%, but was 3.4% when considering only goats undergoing elective procedures. Multivariable analysis showed that gastrointestinal surgeries [odds ratio (OR) 19.17, standard error (SE) 12.99, 95% confidence interval (CI) 5.08-72.33; p < 0.01] and requirement for perianesthetic norepinephrine infusion (OR 10.85, SE 8.82, 95% CI 2.21-53.33; p < 0.01) were associated with increased mortality. Maintaining other variables equal, the use of perianesthetic ketamine infusion was associated with decreased mortality (OR 0.09, SE 0.09, 95% CI 0.01-0.73; p = 0.02). Anesthesia-related or anesthesia-contributory complications included hypothermia (52.4%), bradycardia (38.1%), hypotension (35.3%), hypoxemia (14.8%), regurgitation/aspiration (7.3%), azotemia/acute renal failure (4.6%), myopathies/neuropathies (4.1%) and fever of unknown origin (2.7%). CONCLUSIONS AND CLINICAL RELEVANCE: In this population, gastrointestinal surgeries and the requirement for perianesthetic norepinephrine infusion were associated with increased mortality in goats undergoing general anesthesia, while ketamine infusion may have a protective effect.

A non-inferiority study comparing the ultrasound-guided parasacral with a novel greater ischiatic notch plane approach in canine cadavers.

OBJECTIVE: To describe the gross and ultrasound anatomy of the parasacral region and an ultrasound-guided greater ischiatic notch (GIN) plane approach aimed at staining the lumbosacral trunk (LST) in canine cadavers. To evaluate if the ultrasound-guided GIN plane approach is non-inferior to the previously described ultrasound-guided parasacral approach at staining the LST. STUDY DESIGN: Prospective, randomized, non-inferiority experimental anatomic study. ANIMALS: A total of 17 (23.9 ± 5.2 kg) mesocephalic canine cadavers. METHODS: Anatomic and echographic landmarks, and the feasibility of performing a GIN plane technique were evaluated using two canine cadavers. The remaining 15 cadavers had each hemipelvis randomly assigned to be administered either parasacral or GIN plane injection of 0.15 mL kg-1 dye solution. The parasacral region was dissected after injections to assess the staining of LST, cranial gluteal nerve, pararectal fossa and pelvic cavity. The stained LST were removed and processed for histological evaluation of intraneural injections. A one-sided z-test for non-inferiority (non-inferiority margin -14%) was used to statistically evaluate the success of the GIN plane versus the parasacral approach. Data were considered statistically significant when p < 0.05. RESULTS: The GIN plane and parasacral approach stained the LST in 100% and 93.3% of the injections, respectively. The success rate difference between treatments was 6.7% [95% confidence interval, -0.6 to 19.0%; p < 0.001 for non-inferiority]. The GIN plane and parasacral injections stained the LST for 32.7 ± 16.8 mm and 43.1 ± 24.3 mm, respectively (p = 0.18). No evidence of intraneural injection was found. CONCLUSIONS AND CLINICAL RELEVANCE: The ultrasound-guided GIN plane technique resulted in nerve staining that was non-inferior to the parasacral technique and may be considered an alternative to the parasacral approach to block the LST in dogs.

Effect of end-inspiratory pause on airway and physiological dead space in anesthetized horses.

OBJECTIVE: To evaluate the impact of a 30% end-inspiratory pause (EIP) on alveolar tidal volume (VTalv), airway (VDaw) and physiological (VDphys) dead spaces in mechanically ventilated horses using volumetric capnography, and to evaluate the effect of EIP on carbon dioxide (CO2) elimination per breath (Vco2br-1), PaCO2, and the ratio of PaO2-to-fractional inspired oxygen (PaO2:FiO2). STUDY DESIGN: Prospective research study. ANIMALS: A group of eight healthy research horses undergoing laparotomy. METHODS: Anesthetized horses were mechanically ventilated as follows: 6 breaths minute-1, tidal volume (VT) 13 mL kg-1, inspiratory-to-expiratory time ratio 1:2, positive end-expiratory pressure 5 cmH2O and EIP 0%. Vco2br-1 and expired tidal volume (VTE) of 10 consecutive breaths were recorded 30 minutes after induction, after adding 30% EIP and upon EIP removal to construct volumetric capnograms. A stabilization period of 15 minutes was allowed between phases. Data were analyzed using a mixed-effect linear model. Significance was set at p < 0.05. RESULTS: The EIP decreased VDaw from 6.6 (6.1-6.7) to 5.5 (5.3-6.1) mL kg-1 (p < 0.001) and increased VTalv from 7.7 ± 0.7 to 8.6 ± 0.6 mL kg-1 (p = 0.002) without changing the VTE. The VDphys to VTE ratio decreased from 51.0% to 45.5% (p < 0.001) with EIP. The EIP also increased PaO2:FiO2 from 393.3 ± 160.7 to 450.5 ± 182.5 mmHg (52.5 ± 21.4 to 60.0 ± 24.3 kPa; p < 0.001) and Vco2br-1 from 0.49 (0.45-0.50) to 0.59 (0.45-0.61) mL kg-1 (p = 0.008) without reducing PaCO2. CONCLUSIONS AND CLINICAL RELEVANCE: The EIP improved oxygenation and reduced VDaw and VDphys, without reductions in PaCO2. Future studies should evaluate the impact of different EIP in healthy and pathological equine populations under anesthesia.

Lumbosacral plexus block using a combination of ultrasound-guided lateral pre-iliac and parasacral approaches in cats.

OBJECTIVE: To describe an ultrasound-guided lateral pre-iliac (LPI) and parasacral (PS) approach in feline cadavers (phase I) and compare the perioperative analgesic use and complications in cats administered LPI and PS blocks (group PNB) or epidural anesthesia (group EPI) for pelvic limb surgery (phase II). STUDY DESIGN: Experimental uncontrolled, anatomic and retrospective cohort study. ANIMALS: A group of eight feline cadavers and 52 medical records. METHODS: Bilateral LPI and PS approaches with 0.1 mL kg-1 of dye to stain the femoral and obturator nerves and the lumbosacral trunk, respectively, were performed on each cadaver. Nerve staining effect was evaluated upon dissections (phase I). Perioperative analgesics use, and complication rates were retrospectively compared between groups PNB and EPI (phase II). Continuous data were compared using the Mann-Whitney U test and the prevalence of events with Fisher's exact test. Differences were considered significant when p < 0.05. RESULTS: Dissections revealed that the LPI approach stained 94% and 75% of the femoral and obturator nerves, respectively. The PS approach stained 100% of the lumbosacral trunks. Cats enrolled in group PNB (n = 23) were administered lower doses of intraoperative opioids than those in group EPI (n = 25) (p = 0.006). Intraoperative rescue analgesia was required in 60% and 17.4% of cats enrolled in groups EPI and PNB, respectively (p = 0.003). Group PNB required more intraoperative anticholinergics than group EPI (p = 0.02). There were no differences in postoperative pain scores, analgesic use and complication rates. CONCLUSIONS AND CLINICAL RELEVANCE: The ultrasound-guided LPI and PS approach stained the femoral/obturator nerves and the lumbosacral trunk, respectively, in feline cadavers. Furthermore, PNB was associated with lower intraoperative opioid use and similar postoperative pain and analgesic use compared with epidural anesthesia in a cohort of cats undergoing surgery of the pelvic limb.

Early high antibody titre convalescent plasma for hospitalised COVID-19 patients: DAWn-plasma.

BACKGROUND: Several randomised clinical trials have studied convalescent plasma for coronavirus disease 2019 (COVID-19) using different protocols, with different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralising antibody titres, at different time-points and severities of illness. METHODS: In the prospective multicentre DAWn-plasma trial, adult patients hospitalised with COVID-19 were randomised to 4 units of open-label convalescent plasma combined with standard of care (intervention group) or standard of care alone (control group). Plasma from donors with neutralising antibody titres (50% neutralisation titre (NT50)) ≥1/320 was the product of choice for the study. RESULTS: Between 2 May 2020 and 26 January 2021, 320 patients were randomised to convalescent plasma and 163 patients to the control group according to a 2:1 allocation scheme. A median (interquartile range) volume of 884 (806-906) mL) convalescent plasma was administered and 80.68% of the units came from donors with neutralising antibody titres (NT50) ≥1/320. Median time from onset of symptoms to randomisation was 7 days. The proportion of patients alive and free of mechanical ventilation on day 15 was not different between both groups (convalescent plasma 83.74% (n=267) versus control 84.05% (n=137)) (OR 0.99, 95% CI 0.59-1.66; p=0.9772). The intervention did not change the natural course of antibody titres. The number of serious or severe adverse events was similar in both study arms and transfusion-related side-effects were reported in 19 out of 320 patients in the intervention group (5.94%). CONCLUSIONS: Transfusion of 4 units of convalescent plasma with high neutralising antibody titres early in hospitalised COVID-19 patients did not result in a significant improvement of clinical status or reduced mortality.

Erector spinae plane block at the thoracolumbar spine: a canine cadaveric study.

OBJECTIVE: To investigate the injectate spread and nerve staining of ultrasound-guided erector spinae plane (ESP) injections at the thoracolumbar spine in canine cadavers. STUDY DESIGN: Prospective, randomized, descriptive, anatomic study. ANIMALS: A total of 15 canine cadavers. METHODS: The location of the medial and lateral branches of the dorsal branches of the spinal nerves (DBSN) from the tenth thoracic (T10) to the third lumbar vertebra (L3) were identified by dissection of three cadavers. ESP injections of dye (0.5 mL kg-1) were performed in seven cadavers using as landmarks the T12 transverse process (ESPTp) on one side and the lateral aspect of the T12 mammillary process (ESPMp) on the opposite side. Additionally, five cadavers were injected with dye (0.5 mL kg-1) bilaterally on the lateral aspect of the L2 mammillary process (ESPMp_L2). Nerve staining effect was analyzed after gross anatomic dissections. The number of stained nerves was analyzed using the Mann-Whitney U test. RESULTS: Gross anatomic dissections showed that the medial and lateral branches of the DBSN change their path in relation to the epaxial muscles caudal to T11. Approaches ESPTp and ESPMp at T12 stained 2 (0-2) and 3 (2-4) medial (p = 0.01) and 3 (3-4) and 2 (0-2) lateral (p = 0.03) branches, respectively. Injection ESPMp_L2 stained 3 (2-4) medial and 2 (0-3) lateral branches. Injections ESPMp and ESPMp_L2 produced a preferential cranial spread from the injection site. No ventral branches of the spinal nerves were stained with either technique. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that the mammillary process should be used as anatomic landmark to perform ultrasound-guided ESP blocks in the thoracolumbar spine caudal to T11 when targeting the medial branches of the DBSN. Injections should be performed one spinal segment caudal to the level intended to desensitize.

Pericapsular hip desensitization in dogs: a cadaveric study and case series.

OBJECTIVE: To develop and assess the efficacy of an ultrasound (US)-guided pericapsular hip desensitization (PHD) technique in dogs. STUDY DESIGN: Prospective, randomized, anatomical study and a case series. ANIMALS: A total of 30 healthy dogs, eight canine cadavers and seven dogs with hip osteoarthritis. METHODS: After studying the US anatomy of the medial aspect of the coxofemoral joint and determining an acoustic window to perform an US-guided PHD in healthy dogs, the US-guided PHD was performed bilaterally in canine cadavers. A low [(LV) 0.1 mL kg-1] and high [(HV) 0.2 mL kg-1] volume of dye was injected per hip on each cadaver. The staining of the pericapsular nerves was assessed by anatomical dissection, and comparison between LV and HV was assessed using Fisher's exact test. Then, the US-guided PHD was performed using a triamcinolone-bupivacaine solution in dogs with hip osteoarthritis. Dynamic pain response was assessed before and after injection. The canine brief pain inventory (CBPI) questionnaire was used to assess treatment efficacy and duration. RESULTS: The US-guided PHD could be performed by inserting the needle between the iliopsoas muscle and the periosteum of the ilium. The articular branches of the femoral and obturator nerves were stained in all cadavers using both volumes. The main femoral nerve was never stained, but the main obturator nerve was stained in 37.5% and 100% of injections using LV and HV, respectively (p = 0.026). Treated animals showed decreased dynamic pain response after the injection. Compared with baseline, CBPI scores were reduced by ≥ 50% for ≥ 12 weeks in all but one dog. CONCLUSIONS AND CLINICAL SIGNIFICANCE: The US-guided PHD with both 0.1 and 0.2 mL kg-1 volumes stained the articular branches of the femoral and obturator nerves in canine cadavers and was associated with clinical improvement in dogs with hip osteoarthritis.

Aspergillusfumigatus Recognition by Dendritic Cells Negatively Regulates Allergic Lung Inflammation through a TLR2/MyD88 Pathway.

Aspergillus fumigatus is an opportunistic fungal pathogen responsible for a spectrum of clinical manifestations. Dendritic cells recognize pathogen-associated molecular patterns of Aspergillus via two main receptor families, Toll-like receptors (TLRs) and C-type lectin receptors (CLR). Here, the importance of TLR and CLR signaling in the regulation of T-helper cell type 2 (Th2) responses was analyzed using a mouse model based on the transfer of bone marrow-derived dendritic cells (BMDCs) pulsed with A. fumigatus conidia. BMDCs were generated from mice deficient in either MyD88 or MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1). Both the MyD88 and MALT1 signaling pathway in BMDCs contributed to the production of inflammatory cytokines induced by A. fumigatus conidia. Mice sensitized with MyD88-/- BMDCs pulsed in vitro with A. fumigatus conidia showed an exacerbated allergic inflammation, with stronger eosinophil recruitment in the BAL and higher Th2 cytokine production compared with mice sensitized with wild-type or MALT1-/- BMDCs. This exacerbation was not observed when MyD88-/- BMDCs were pulsed with Cladosporium sphaerospermum, a nonpathogenic mold. A lack of TLR2 signaling recapitulated the exacerbation of the A. fumigatus Th2 response observed in the absence of MyD88 signaling, whereas TLR2 agonist dampened the response induced with A. fumigatus and C. sphaerospermum conidia. IL-10 production by BMDCs in response to A. fumigatus was dependent on the expression of TLR2 and MyD88. IL-10-/- BMDCs exacerbated, whereas MyD88-/- BMDCs supplemented with exogenous IL-10 decreased the allergic pulmonary inflammation. These results indicate that TLR2/MyD88-specific recognition of PAMPs from A. fumigatus conidia can upregulate IL-10 production and downregulate lung eosinophilia and the development of a Th2 response.

SARS-CoV-2 neutralising antibody testing in Europe: towards harmonisation of neutralising antibody titres for better use of convalescent plasma and comparability of trial data.

We compared the performance of SARS-CoV-2 neutralising antibody testing between 12 European laboratories involved in convalescent plasma trials. Raw titres differed almost 100-fold differences between laboratories when blind-testing 15 plasma samples. Calibration of titres in relation to the reference reagent and standard curve obtained by testing a dilution series reduced the inter-laboratory variability ca 10-fold. The harmonisation of neutralising antibody quantification is a vital step towards determining the protective and therapeutic levels of neutralising antibodies.

Evaluation of the effect of ultrasound guidance on the accuracy of intercostal nerve injection: a canine cadaveric study.

OBJECTIVE: To develop an ultrasound-guided approach to intercostal nerve injection and to compare the success rate of intercostal nerve injections using blind or ultrasound-guided technique in canine cadavers. STUDY DESIGN: Prospective, randomized, descriptive, experimental anatomic study. ANIMALS: A total of 14 mid-sized adult canine cadavers. METHODS: Ultrasound landmarks were identified by dissection of four cadavers and used to develop an ultrasound-guided technique. The remaining 10 cadavers were randomly assigned to blind (five cadavers) or ultrasound-guided (five cadavers) injections of the third to the ninth intercostal nerves bilaterally with 0.03 mL kg-1 of colorant per injection. The target for intercostal injections was the caudal border of the respective rib, between the internal intercostal membrane and the parietal pleura. Additionally, displacement of the parietal pleura without visible intramuscular distribution was considered the end point for ultrasound-guided injections. For each cadaver, a practitioner in training performed the blocks on one hemithorax, while an experienced practitioner performed the blocks on the opposite hemithorax. Injections were considered successful if ≥1 cm of the target nerve was stained with colorant upon dissection. Success rates and length of nerve staining were analyzed with Fisher's exact and t tests, respectively. Data were considered statistically different with p < 0.05. RESULTS: Success rates of blind and ultrasound-guided technique were 57.1% and 91.4%, respectively (p < 0.0001). The length of intercostal nerve staining was 3.1 ± 1.2 cm and 3.6 ± 1.0 cm using blind and ultrasound-guided techniques, respectively (p = 0.02). No differences were observed between the two practitioners for blind (p = 0.33) and ultrasound-guided techniques (p = 0.67). CONCLUSIONS AND CLINICAL RELEVANCE: Ultrasound guidance improves the accuracy of intercostal nerve injections when compared with blind technique, independently of the level of expertise in regional anesthesia.

Comparison between two approaches for the transversus abdominis plane block in canine cadavers.

OBJECTIVE: To compare the dye distribution following either two lateral abdominal or one lateral abdominal and one subcostal ultrasound-guided transversus abdominis plane (TAP) injections of a clinically relevant volume of dye solution in dogs. STUDY DESIGN: Randomized cadaveric study. ANIMALS: A total of eight canine cadavers. METHODS: On one side of each cadaver, two TAP injections were performed on the lateral aspect of the abdomen (approach LL), caudal to the last rib and cranial to the iliac crest. On the contralateral hemiabdomen, one subcostal (caudal to the costal arch) and one lateral abdominal injection (between last rib and iliac crest), were performed (approach SL). Side allocation was randomly determined. A spinal needle was introduced in-plane to the transducer for each injection of methylene blue (0.25 mL kg-1). All cadavers were dissected to assess dye distribution and number of stained target nerves. RESULTS: All injections were performed in the TAP. The proportion of target nerve staining was 53.5% versus 80.4% with approaches LL and SL, respectively (p = 0.005). Approach LL stained the first lumbar (L1) spinal nerve in 100% of injections and ninth thoracic (T9), T10, T11, T12, T13 and L2 were stained in 0%, 0%, 37.5%, 62.5%, 87.5% and 87.5% of injections, respectively. Approach SL stained T11, L1 and L2 in 100% of injections and T9, T10, T12 and T13 were stained in 37.5%, 87.5%, 75% and 62.5% of injections, respectively. Approach SL resulted in greater staining of nerves cranial to T12 compared with approach LL. The two approaches were equivalent in staining nerves caudal to T12. CONCLUSIONS AND CLINICAL RELEVANCE: Approach SL provided a broader distribution of the injected solution than approach LL, which may result in a larger blocked area in live animals undergoing celiotomy.

Transversus abdominis plane block in cat cadavers: anatomical description and comparison of injectate spread using two- and three-point approaches.

OBJECTIVE: To describe the sonoanatomy of the abdominal wall in live cats and to compare the distribution pattern of two versus three ultrasound-guided transversus abdominis plane (TAP) injections using clinically applicable volumes of lidocaine-dye solution in cat cadavers. STUDY DESIGN: Prospective anatomical study. ANIMALS: A total of eight client-owned healthy cats and eight cat cadavers. METHODS: Ultrasound anatomy of the abdominal wall, landmarks and sites for needle access were determined in live cats. Ultrasound-guided TAP injections were performed in eight thawed cat cadavers. Volumes of 0.25 or 0.16 mL kg-1 per point of a lidocaine-dye solution were injected using either two [subcostal and preiliac (SP)] or three [subcostal, retrocostal and preiliac (SRP)] injection points, respectively. Each cadaver was then dissected to determine the injectate distribution and the number of thoracolumbar nerves stained with each approach. The target nerves were defined as the ventromedial branches of the thoracic nerves 10 (T10), T11, T12, T13 and lumbar nerves 1 (L1) and L2. RESULTS: Sonoanatomy was consistent with anatomy upon dissection and the TAP was identified in all cadavers. A total of 16 subcostal, 16 preiliac and nine retrocostal TAP injections were performed. The overall staining success rate of the target nerves was 66.7% and 92.6% for the SP and SPR approaches, respectively (p = 0.02). The ventromedial branches of T10, T11, T12, T13, L1 and L2 were stained in 57.1%, 100.0%, 85.7%, 28.6%, 42.9% and 85.7%, and in 66.7%, 100.0%, 100.0%, 100.0%, 88.9% and 100.0% of the cases with the SP and SRP approaches, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: The SRP approach allowed a broader distribution around the target nerves, whereas a staining gap was observed at T13 and L1 with the SP approach. Further studies are necessary to investigate the analgesic effect of these approaches in a clinical setting.

The effect of erector spinae plane block on perioperative analgesic consumption and complications in dogs undergoing hemilaminectomy surgery: a retrospective cohort study.

OBJECTIVE: To compare the perioperative use of analgesics and complication rates in dogs administered an erector spinae plane (ESP) block or a traditional opioid-based (OP) treatment as part of analgesic management during hemilaminectomy. STUDY DESIGN: Retrospective cohort study. ANIMALS: Medical records of 114 client-owned dogs. METHODS: General data included demographics, duration of procedure, number of laminae fenestrated, perioperative use of steroid and non-steroidal anti-inflammatory drugs. Intra- and postoperative analgesics used in 48 hours and complications rates were compared between groups. Opioid use was expressed in morphine equivalents [ME (mg kg-1)]. Continuous data were compared using the Mann-Whitney U test and incidence of events with a Fisher's exact tests. Multiple linear regression was used to evaluate association between perioperative ME consumption (dependent variable) with other independent variables. Data are presented as median (range). Differences were considered significant when p < 0.05. RESULTS: Group ESP comprised 42 dogs and group OP 72 dogs. No differences were observed in the general data. Intraoperative ME was 0.65 (0.20-3.74) and 0.79 (0.19-5.60) mg kg-1 in groups ESP and OP, respectively (p = 0.03). Intraoperative infusion of lidocaine was administered intravenously (IV) to 23.8% and 68% of groups ESP and OP, respectively (p < 0.0001). Intraoperative infusion of ketamine was administered IV to 21% and 40% of groups ESP and OP, respectively (p = 0.04). Regression analysis revealed the ESP block as the only independent variable affecting the perioperative ME consumption. Pharmacological intervention to treat cardiovascular complications was administered to 21.4% and 47.2% of dogs in groups ESP and OP, respectively (p = 0.008). There were no differences in postoperative complication rates. CONCLUSIONS AND CLINICAL RELEVANCE: ESP block was associated with reduced perioperative opioid consumption, intraoperative adjuvant analgesic use and incidence of pharmacological interventions to treat cardiovascular complications in dogs undergoing hemilaminectomy.

Progressive Control of Streptococcus agalactiae-Induced Innate Inflammatory Response Is Associated with Time Course Expression of MicroRNA-223 by Neutrophils.

Group B streptococcus (GBS) is a human-pathogenic bacterium inducing a strong inflammatory response that may be detrimental for host tissues if not finely regulated. The inflammatory response can be modulated by different molecular mechanisms, among which growing evidence points toward the crucial role of microRNAs (miRNAs). Regarding innate inflammatory response, studies have reported that miR-223 is essential for the control of granulocyte proliferation and activation. Moreover, a number of investigations on miRNA expression profiling performed in various inflammatory settings have revealed that miR-223 is among the top differentially expressed miRNAs. Yet the dynamic pattern of expression of miR-223 in vivo with respect to the evolution of the inflammatory process, especially in microbial infection, remains elusive. In this study, we analyzed the kinetic expression of miR-223 in an inflammatory model of GBS-induced murine pneumonia and looked for correlates with inflammatory markers, including innate cell infiltrates. We found that miR-223 expression is rapidly induced at very early time points (3 to 6 h postinfection [p.i.]) mainly by lung-infiltrating neutrophils. Interestingly, the level of miR-223 accumulating in the lungs remains higher at later stages of infection (24 h and 48 h p.i.), and this correlates with reduced expression of primary inflammatory cytokines and chemokines and with a shift in infiltrating monocyte and macrophage subtypes toward a regulatory phenotype. Transient inhibition of miR-223 by an antagomir resulted in significant increase of CXCL2 expression and partial enhancement of infiltrating neutrophils in GBS-infected lung tissues. This suggests the potential contribution of miR-223 to the resolution phase of GBS-induced acute inflammation.

Synergetic effects of immune challenge and stress depress cortisol, inflammatory response and antioxidant activity in fish-eating Myotis.

One of the most common tools in conservation physiology is the assessment of environmental stress via glucocorticoid measurement. However, little is known of its relationship with other stress-related biomarkers, and how the incidence of an immune challenge during long-term stress could affect an individual's overall stress response. We investigated here the relationship between basal and post-acute stress fecal cortisol metabolite (FC) with different antioxidant enzymes, oxidative damage and immune parameters in the fish-eating bat, Myotis vivesi We found that in both basal and post-stress conditions, FC was highly related with a number of antioxidant enzymes and immune parameters, but not to oxidative damage. We also assessed changes of FC through the seasons. Basal FC samples and stress reactivity after short-duration stress displayed similar levels during summer, autumn and early winter, but lower concentrations in late winter. Stress reactivity after long-duration stress was greater in summer and early winter. Finally, we tested the effect of a simultaneous exposure to a long, strong stress stimulus with an immune response stimulation by administrating adrenocorticotropic hormone (ACTH) and phytohemagglutinin (PHA) after 42 h. Results showed that when both stimuli were administrated, FC concentrations, inflammation and some antioxidant activity were lowered in comparison with the control and individual administration of the challenges. Our findings support the idea that animals maintain constant basal glucocorticoid levels when living in challenging environments, but response to acute stress differs seasonally and immune defense mechanisms and stress responses might be compromised when confronted with multiple challenges.

Ultrasound-guided erector spinae plane block in canine cadavers: relevant anatomy and injectate distribution.

OBJECTIVE: To investigate the distribution and nerve staining of two volumes of lidocaine-dye solution after ultrasound-guided erector spinae plane (ESP) injections in canine cadavers. STUDY DESIGN: Experimental cadaveric study. ANIMALS: A total of nine canine cadavers. METHODS: ESP injections were performed between the longissimus thoracis muscle and the dorsolateral edge of the ninth thoracic transverse process. Two cadavers were transversally cryosectioned after unilateral ESP injections [0.6 mL kg-1; high volume (HV)]. In seven cadavers, bilateral ESP injections with HV or low volume (0.3 mL kg-1; LV) were performed. Gadodiamide was added to the injectate for two cadavers and magnetic resonance imaging (MRI) was performed pre- and post-injection. Injectate distribution and nerve staining of the branches of the spinal nerves were recorded after gross anatomical dissection. The thoracic paravertebral and epidural spaces were examined for dye solution. RESULTS: Cryosections, MRI and gross dissections showed that the injectate spread dorsally to the transverse processes, over the ventromedial aspect of the longissimus thoracis muscle where the medial and lateral branches of the dorsal branches of the spinal nerves are located. LV and HV stained a median (range) of 4 (2-7) and 4 (3-8) medial branches, respectively (p = 0.52). LV and HV stained 4 (2-5) and 5 (4-7) lateral branches (p = 0.26), respectively. Ventral branches were not stained, and dye was not identified in the epidural or paravertebral spaces. CONCLUSIONS: and clinical relevance Medial and lateral branches were consistently stained over several spinal segments. The number of nerves stained was not different with HV or LV, and the ventral branches of the spinal nerves were not stained in any cadaver. ESP block may find a clinical application to desensitize structures innervated by the medial and lateral branches of the dorsal branches of the thoracic spinal nerves.

Changes in serum cortisol and blood glucose concentrations in anesthetized, pain-free dogs administered fentanyl.

OBJECTIVE: To evaluate whether fentanyl administered at analgesic doses in pain-free anesthetized dogs increases the serum cortisol or blood glucose concentrations and is associated with postanesthetic dysphoria. STUDY DESIGN: Experimental, blinded, randomized crossover. ANIMALS: A group of six adult research dogs. METHODS: Each dog was anesthetized twice and was administered fentanyl or saline with a 15-day wash-out period. Treatment allocation was randomly assigned via a closed envelope technique. Cortisol and glucose concentrations were measured on arrival in the research room (TPRE), induction of general anesthesia (TIND), extubation (TEXT) and 1 hour after extubation (TPOST). Dogs were premedicated with methadone (0.1 mg kg-1) and carprofen (4 mg kg-1) intravenously (IV), anesthesia induced with propofol (4-6 mg kg-1) IV and maintained with isoflurane in oxygen. Standard anesthesia monitoring was performed throughout the experiment. Fentanyl (5 µg kg-1 over 90 seconds followed by 7.5 µg kg-1 hour -1) or an equivalent amount in mL of saline solution were administered IV for 60 minutes. TPRE behavior scores and recovery scores were evaluated using descriptive 4-point scales. Data from serum cortisol and blood glucose concentrations were analyzed with a Split Plot on time test, whereas recovery scores were analyzed using a Wilcox match-pairs signed rank test. Statistical significance was set at p < 0.05. RESULTS: There were no significant increases in serum cortisol and blood glucose concentrations over time, and there were no differences between treatments. None of the dogs developed postanesthetic dysphoria with either treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Fentanyl, administered at analgesic doses to healthy, pain-free, anesthetized dogs, was not associated with significant changes in serum cortisol or glucose concentrations in the studied population.

A retrospective analysis of the epidural use of bupivacaine 0.0625-0.125% with opioids in bitches undergoing cesarean section.

Epidural anesthesia, often used during cesarean surgery, can exacerbate hypotension from general anesthesia and delay discharge due to motor block. Decreasing the local anesthetic dose might reduce those complications. Cases of dogs undergoing cesarean section that were anesthetized without epidural (n = 29) (control) and dogs with low-dose epidural bupivacaine with fentanyl or buprenorphine (n = 37) were reviewed. The incidence of hypotension was equal between groups. Intraoperative opioids were administered more to control (93%) than to treated dogs (18%; P < 0.0001). Epidural bupivacaine 0.0625-0.125% combined with an opioid reduced the use of intraoperative opioids and did not exacerbate arterial hypotension during cesarean section in anesthetized dogs.

Analyse rétrospective de l'utilisation de bupivacaine 0,0625­0,125 % avec des opioïdes lors d'épidurale chez des chiennes soumises à une césarienne. L'anesthésie épidurale, souvent utilisée lors d'une césarienne, peut exacerber l'hypotension due à l'anesthésie générale et retarder le congé à cause d'un bloc moteur. Une diminution de la dose d'anesthésique local pourrait réduire ces complications. Une revue fut effectuée des cas de chiennes soumises à une césarienne et anesthésiées sans épidurale (n = 29) (témoin) et des chiennes avec une épidurale en utilisant une faible dose de bupivacaine avec du fentanyl ou de la buprenorphine (n = 37). L'incidence d'hypotension était égale entre les groupes. Des opioïdes intra-opératoires furent administrés plus fréquemment chez les témoins (93 %) que chez les animaux traités (18 %; P < 0,001). De la bupivacaine 0,0625­0,125 % en épidurale combinée à un opioïde réduisit l'utilisation d'opioïdes intra-opératoires et n'a pas exacerbé l'hypotension artérielle durant la césarienne chez des chiennes anesthésiées.(Traduit par Dr Serge Messier).