Comparison of bupivacaine liposome injectable solution and fentanyl for postoperative analgesia in dogs undergoing limb amputation.

OBJECTIVE: The objectives of the study were to compare the clinical efficacy and adverse effects of two analgesic protocols consisting of bupivacaine liposome injectable solution (BLIS) and 0.5% bupivacaine and fentanyl for postsurgical analgesia in dogs undergoing limb amputation. STUDY DESIGN: Randomized, double-blind, prospective, controlled, intent-to-treat, clinical noninferiority trial. ANIMALS: Forty client-owned dogs. METHODS: Dogs undergoing amputation were randomly assigned to either the BLIS or control group. Postoperative pain, sedation, nausea, and amount eaten were assessed using appropriate scales at 6, 12, 18, and 24 h by trained individuals blinded to the treatment protocol. Rescue analgesia was provided for Glasgow composite measure pain scale (short form) (CMPS-SF) scores of 5 or above. Clients were requested to pain score their dogs at home using a visual analogue scale (VAS) for 48 h following discharge. RESULTS: Forty dogs completed this study (20 control dogs and 20 BLIS dogs). The BLIS and control groups were equivalent for sedation, nausea, amount eaten, and pain, at all time periods except at 6 h (p < .01), when the BLIS group pain score was lower. CONCLUSION: The BLIS provided equivalent analgesia with fewer adverse effects than fentanyl constant rate infusion (CRI) following limb amputation. Rescue analgesia was provided to five dogs in the BLIS group and four in the control group, and there was no statistical difference. Nausea scores did not differ statistically. CLINICAL SIGNIFICANCE: As BLIS provides equivalent analgesia, this may allow for decreased reliance on opioids in the immediate postoperative period.

Evaluation of preoperative rectus sheath block with bupivacaine for analgesia in cats undergoing ovariohysterectomy: a cadaveric and randomized clinical study.

OBJECTIVE: Phase 1: to determine the feasibility of desensitizing ventral branches of spinal nerves within the rectus sheath using an ultrasound-guided rectus sheath block (USRSB). Phase 2: to determine the effect of preoperative USRSB on intraoperative responses to surgical stimulation and postoperative pain. STUDY DESIGN: Cadaveric study and prospective, randomized, blinded, parallel-arm clinical trial. ANIMALS: A group of five cat cadavers and 37 shelter-owned cats undergoing ovariohysterectomy. METHODS: Phase 1: anatomical dissection was performed on one uninjected cadaver. Abdominal walls were dissected in four cadavers (eight hemiabdomens) following bilateral USRSB using 1:1 new methylene blue and 0.5% bupivacaine (0.8 mL kg-1 total). Phase 2: preoperative bilateral USRSB was performed with 0.8 mL kg-1 of 0.25% bupivacaine (RSB) or equivalent volume of 0.9% saline (CONTROL). Intraoperative systolic arterial blood pressure (SAP), heart rate (HR), respiratory rate (fR) and vaporizer setting (vap%) were recorded before skin incision, during celiotomy and abdominal wall closure. In recovery, cats were administered robenacoxib (2 mg kg-1; CONTROL) or 0.9% saline (0.1 mL kg-1; RSB) subcutaneously. Postoperative pain was evaluated for 6 hours using the Glasgow Composite Measure Pain Scale. RESULTS: Phase 1: spinal nerves T9-L3 were identified within the rectus sheath, and stained in 0%, 40%, 63%, 75%, 100%, 88%, 50% and 13% of hemiabdomens, respectively. Phase 2: 37 cats were included (RSB, n = 17; CONTROL, n = 20). Intraoperatively, SAP, HR and fR were not significantly different between groups. Vap% was significantly lower in RSB during celiotomy (p = 0.036) and closure (p = 0.044). Postoperatively, RSB cats were 5.3 times (95% CI 1.8-8.3) more likely to require rescue analgesia than CONTROL cats. CONCLUSIONS AND CLINICAL RELEVANCE: During surgery, USRSB with bupivacaine offered minor benefits and provided markedly less postoperative analgesia than robenacoxib, indicating that relying on USRSB provides insufficient postoperative analgesia for ovariohysterectomy in cats.

CD38 plays an age-related role in cholinergic deregulation of airway smooth muscle contractility.

BACKGROUND: Allergen-induced airway hyperresponsiveness in neonatal mice, but not adult mice, is caused by elevated innervation and consequent cholinergic hyperstimulation of airway smooth muscle (ASM). Whether this inflammation-independent mechanism contributes to ASM hypercontraction in childhood asthma warrants investigation. OBJECTIVE: We aimed to establish the functional connection between cholinergic stimulation and ASM contractility in different human age groups. METHODS: First, we used a neonatal mouse model of asthma to identify age-related mediators of cholinergic deregulation of ASM contractility. Next, we conducted validation and mechanistic studies in primary human ASM cells and precision-cut lung slices from young (<5 years old) and adult (>20 years old) donor lungs. Finally, we evaluated the therapeutic potential of the identified cholinergic signaling mediators using culture models of human ASM hypercontraction. RESULTS: ASM hypercontraction due to cholinergic deregulation in early postnatal life requires CD38. Mechanistically, cholinergic signaling activates the phosphatidylinositol 3-kinase/protein kinase B pathway in immature ASM cells to upregulate CD38 levels, thereby augmenting the Ca2+ response to contractile agonists. Strikingly, this early-life, CD38-mediated ASM hypercontraction is not alleviated by the ß-agonist formoterol. CONCLUSIONS: The acetylcholine-phosphatidylinositol 3-kinase/protein kinase B-CD38 axis is a critical mechanism of airway hyperresponsiveness in early postnatal life. Targeting this axis may provide a tailored treatment for children at high risk for allergic asthma.

Effect of the reverse Trendelenburg position on the incidence of gastroesophageal reflux in dogs anesthetized for elective stifle surgery.

OBJECTIVE: To determine if a 15° reverse Trendelenburg position decreases the incidence of gastroesophageal reflux (GER) compared with a horizontal position in dogs anesthetized for stifle surgery. STUDY DESIGN: Prospective, randomized parallel-arm study. ANIMALS: A total of 44 healthy client-owned dogs were enrolled and data from 36 dogs were analyzed. METHODS: Dogs requiring preoperative radiographs under anesthesia, or with a history of gastrointestinal signs or administered gastroprotectant therapy within 1 month of surgery were excluded. Anesthesia protocol was standardized to include hydromorphone, dexmedetomidine, ketamine, propofol and isoflurane. Dogs were randomly assigned at enrollment to be positioned in a 15° reverse Trendelenburg or a horizontal position for surgery. Continuous pH monitoring was documented throughout the procedure with a 6.4 Fr (2.13 mm) esophageal pH probe positioned in the distal esophagus via the oral cavity. GER was defined as pH < 4.0 (acidic) or > 7.5 (alkaline) for more than 30 seconds. The proportions of dogs developing GER were compared between groups using Fisher's exact test. Time to reflux was compared using survival curves and the Gehan-Breslow-Wilcoxon test. Statistical significance was set as p < 0.05. RESULTS: An episode of GER occurred in 11/36 (30%) dogs. Reflux was alkaline in two dogs and acidic in nine dogs. The proportion of dogs with GER was 5/18 (28%) and 6/18 (33%) for dogs in the reverse Trendelenburg position and horizontal position, respectively, and was not statistically significant (p > 0.99). Median (range) time until reflux was 44 (23-135) and 44.5 (9-56) minutes when dogs were positioned in reverse Trendelenburg position and horizontal position, respectively (p = 0.66; two-tailed Mann-Whitney U test). CONCLUSIONS AND CLINICAL RELEVANCE: Positioning the surgery table in a 15° rostral elevation for dogs anesthetized for elective stifle surgical procedures did not decrease the incidence of GER.

Ultrasound-guided rectus sheath block injections in miniature swine cadavers: technique description and distribution of two injectate volumes.

OBJECTIVE: To describe a technique for ultrasound-guided rectus sheath block in pigs and the distribution of two injectate volumes. STUDY DESIGN: Experimental study. ANIMALS: A group of 11 Hanford miniature pig cadavers. METHODS: The lateral border of each rectus abdominis muscle in 10 freshly euthanized pigs was visualized with a 6-15 MHz linear ultrasound probe. A spinal needle was inserted 1 cm cranial to the umbilicus, in-plane and medial to the probe, and advanced dorsal to lateral until the tip was ventral to the internal rectus sheath. Pigs were injected bilaterally with high volume (treatment HV; 0.8 mL kg-1) or low volume (treatment LV; 0.5 mL kg-1) of 1:1 solution of 1% methylene blue and 0.5% bupivacaine (1 mg kg-1) diluted with 0.9% saline. Nerve staining ≥ 1 cm circumferentially was determined by dissection 15 minutes postinjection. The Clopper-Pearson method was used to calculate 95% confidence intervals (CIs) for proportions of stained nerves. In another pig, a 1:1 solution of 1% methylene blue and 74% ioversol contrast was injected, and computed tomography performed at 15 minute intervals after injection. RESULTS: Nerve staining for thoracic (T) spinal nerves T9, T10, T11, T12, T13 and T14 occurred 20%, 60%, 90% 100%, 100% and 50%, and 0%, 20%, 90%, 100%, 100% and 50% of the time in treatments HV and LV, respectively. More nerves were stained in treatment HV in 4/10 animals (40%, 95% CI: 12%-74%) than in treatment LV (0%, 95% CI: 0%-31%). The greatest spread of injectate occurred within the first 15 minutes after injection. CONCLUSIONS AND CLINICAL RELEVANCE: Staining of T11-T14 nerves was the same in both treatments but the higher volume stained more T9-T10 nerves. Based on dye distribution, a rectus sheath block may only provide ventral abdominal analgesia cranial to the umbilicus in pigs.

Species Differences in Metabolism of Soluble Epoxide Hydrolase Inhibitor, EC1728, Highlight the Importance of Clinically Relevant Screening Mechanisms in Drug Development.

There are few novel therapeutic options available for companion animals, and medications rely heavily on repurposed drugs developed for other species. Considering the diversity of species and breeds in companion animal medicine, comprehensive PK exposures in the companion animal patient is often lacking. The purpose of this paper was to assess the pharmacokinetics after oral and intravenous dosing in domesticated animal species (dogs, cats, and horses) of a novel soluble epoxide hydrolase inhibitor, EC1728, being developed for the treatment of pain in animals. Results: Intravenous and oral administration revealed that bioavailability was similar for dogs, and horses (42 and 50% F) but lower in mice and cats (34 and 8%, respectively). Additionally, clearance was similar between cats and mice, but >2× faster in cats vs. dogs and horses. Efficacy with EC1728 has been demonstrated in mice, dogs, and horses, and despite the rapid clearance of EC1728 in cats, analgesic efficacy was demonstrated in an acute pain model after intravenous but not oral dosing. Conclusion: These results demonstrate that exposures across species can vary, and investigation of therapeutic exposures in target species is needed to provide adequate care that addresses efficacy and avoids toxicity.

Pharmacokinetics and clinical effects of xylazine and dexmedetomidine in horses recovering from isoflurane anesthesia.

This study determined the pharmacokinetics and compared the clinical effects of xylazine and dexmedetomidine in horses recovering from isoflurane anesthesia. Six healthy horses aged 8.5 ± 3 years and weighing 462 ± 50 kg were anesthetized with isoflurane for 2 hr under standard conditions on two occasions one-week apart. In recovery, horses received 200 µg/kg xylazine or 0.875 µg/kg dexmedetomidine intravenously and were allowed to recover without assistance. These doses were selected because they have been used for postanesthetic sedation in clinical and research studies. Serial venous blood samples were collected for quantification of xylazine and dexmedetomidine, and the pharmacokinetic parameters were calculated. Two individuals blinded to treatment identity evaluated recovery quality with a visual analog scale. Times to stand were recorded. Results (mean ± SD) were compared using paired t tests or Wilcoxon signed-ranked test with p < .05 considered significant. Elimination half-lives (62.7 ± 21.8 and 30.1 ± 8 min for xylazine and dexmedetomidine, respectively) and steady-state volumes of distribution (215 ± 123 and 744 ± 403 ml/kg) were significantly different between xylazine and dexmedetomidine, whereas clearances (21.1 ± 17.3 and 48.6 ± 28.1 ml/minute/kg), times to stand (47 ± 24 and 53 ± 12 min) and recovery quality (51 ± 24 and 61 ± 22 mm VAS) were not significantly different. When used for postanesthetic sedation following isoflurane anesthesia in healthy horses, dexmedetomidine displays faster plasma kinetics but is not associated with faster recoveries compared to xylazine.

Novel Pathway of Adenosine Generation in the Lungs from NAD+: Relevance to Allergic Airway Disease.

Adenosine and uric acid (UA) play a pivotal role in lung diseases such as asthma and chronic obstructive pulmonary disease (COPD). In the present experiments, we measured adenosine synthesis from nicotinamide adenine dinucleotide (NAD+) in membranes prepared from wild type (WT) and CD38 knockout (CD38KO) mouse lungs, from cultured airway smooth muscle and epithelial cells, and in bronchoalveolar lavage fluid after airway challenge with epidemiologically relevant allergens. Adenosine was determined using an enzymatically coupled assay that produces ATP and is detected by luminescence. Uric acid was determined by ELISA. Exposure of cultured airway epithelial cells to Alternaria alternata extract caused significant nucleotide (NAD+ and ATP) release in the culture media. The addition of NAD+ to membranes prepared from WT mice resulted in faster generation of adenosine compared to membranes from CD38KO mice. Formation of adenosine from NAD+ affected UA and ATP concentrations, its main downstream molecules. Furthermore, NAD+ and adenosine concentrations in the bronchoalveolar lavage fluid decreased significantly following airway challenge with house-dust mite extract in WT but not in CD38KO mice. Thus, NAD+ is a significant source of adenosine and UA in the airways in mouse models of allergic airway disease, and the capacity for their generation from NAD+ is augmented by CD38, a major NADase with high affinity for NAD+. This novel non-canonical NAD+-adenosine-UA pathway that is triggered by allergens has not been previously described in the airways.

A Survey of the Presence of Pharmaceutical Residues in Wastewaters. Evaluation of Their Removal using Conventional and Natural Treatment Procedures.

To encourage the reutilization of treated wastewaters as an adaptation strategy to climate change it is necessary to demonstrate their quality. If this is ensured, reclaimed waters could be a valuable resource that produces very little environmental impact and risks to human health. However, wastewaters are one of the main sources of emerging pollutants that are discharged in the environment. For this, it is essential to assess the presence of these pollutants, especially pharmaceutical compounds, in treated wastewaters. Moreover, the different treatment processes must be evaluated in order to know if conventional and natural treatment technologies are efficient in the removal of these types of compounds. This is an important consideration if the treated wastewaters are used in agricultural activities. Owing to the complexity of wastewater matrixes and the low concentrations of pharmaceutical residues in these types of samples, it is necessary to use sensitive analytical methodologies. In this study, the presence of 11 pharmaceutical compounds were assessed in three different wastewater treatment plants (WWTPs) in Gran Canaria (Spain). Two of these WWTPs use conventional purification technologies and they are located in densely populated areas, while the other studied WWTP is based in constructed wetlands which purify the wastewaters of a rural area. The sampling was performed monthly for two years. A solid phase extraction (SPE) coupled to ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was applied for the analysis of the samples, and the 11 pharmaceuticals were detected in all the studied WWTPs. The concentrations were variable and ranged from ng·L-1 in some compounds like diclofenac or carbamazepine to µg·L-1 in common pharmaceutical compounds such as caffeine, naproxen or ibuprofen. In addition, removal efficiencies in both conventional and natural purification systems were evaluated. Similar removal efficiencies were obtained using different purifying treatments, especially for some pharmaceutical families as stimulants or anti-inflammatories. Other compounds like carbamazepine showed a recalcitrant behavior. Secondary treatments presented similar removal efficiencies in both conventional and natural wastewater treatment plants, but conventional treatments showed slightly higher elimination ratios. Regarding tertiary system, the treatment with highest removal efficiencies was reverse osmosis in comparison with microfiltration and electrodialysis reversal.

CD38/cADPR Signaling Pathway in Airway Disease: Regulatory Mechanisms.

Asthma is an inflammatory disease in which proinflammatory cytokines have a role in inducing abnormalities of airway smooth muscle function and in the development of airway hyperresponsiveness. Inflammatory cytokines alter calcium (Ca2+) signaling and contractility of airway smooth muscle, which results in nonspecific airway hyperresponsiveness to agonists. In this context, Ca2+ regulatory mechanisms in airway smooth muscle and changes in these regulatory mechanisms encompass a major component of airway hyperresponsiveness. Although dynamic Ca2+ regulation is complex, phospholipase C/inositol tris-phosphate (PLC/IP3) and CD38-cyclic ADP-ribose (CD38/cADPR) are two major pathways mediating agonist-induced Ca2+ regulation in airway smooth muscle. Altered CD38 expression or enhanced cyclic ADP-ribosyl cyclase activity associated with CD38 contributes to human pathologies such as asthma, neoplasia, and neuroimmune diseases. This review is focused on investigations on the role of CD38-cyclic ADP-ribose signaling in airway smooth muscle in the context of transcriptional and posttranscriptional regulation of CD38 expression. The specific roles of transcription factors NF-kB and AP-1 in the transcriptional regulation of CD38 expression and of miRNAs miR-140-3p and miR-708 in the posttranscriptional regulation and the underlying mechanisms of such regulation are discussed.

Transversus abdominis plane block in ponies: a preliminary anatomical study.

OBJECTIVE: To describe a single-site transversus abdominis plane (TAP) block technique in horses. STUDY DESIGN: Prospective, descriptive, experimental anatomical study. ANIMALS: Four adult pony cadavers. METHODS: Freshly euthanized ponies were positioned in dorsal recumbency. A 6-13 MHz linear ultrasonic probe was used to scan the abdominal wall bilaterally midway between the last rib and iliac crest in search of the TAP location. By modifying the technique to accommodate the equine anatomy, the TAP was successfully visualized with the transducer positioned in a transverse plane with its side indicator over the intercept of two lines, one connecting the most cranial aspect of the iliac crest and the most caudal extent of the last rib and another originating just caudal to the umbilicus and extending laterally. Each hemiabdomen was injected with 0.5 mL kg-1 of a 1:1 solution of 1% methylene blue and 0.5% bupivacaine via a 21 gauge 10 cm stimulating needle inserted ventral-dorsally and in plane with the ultrasound beam. Approximately 3 hours after injection, the abdomen was dissected and nerves stained over 1 cm in length were identified. RESULTS: Staining was evident from the fourteenth thoracic (T14) to the third lumbar (L3) nerves. The ventral branches of the fifteenth to the eighteenth thoracic nerves (T15-T18) and first and second lumbar nerves (L1 and L2) were stained in three, six, eight, eight, eight and seven of eight injections, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Nerves T16-L2 had over 75% success rate in staining, suggesting that this technique would block transmission from T16 to L2, assuming that staining indicates potential nerve block. Dorsal spread occurred in three of eight hemiabdomens. Further studies developing techniques for the cranial abdomen and adjusting volume and concentration of injectate are warranted.

Comparison between the effects of postanesthetic xylazine and dexmedetomidine on characteristics of recovery from sevoflurane anesthesia in horses.

OBJECTIVE: To compare postanesthetic xylazine and dexmedetomidine on recovery characteristics from sevoflurane anesthesia in horses. STUDY DESIGN: Randomized, crossover study. ANIMALS: Six geldings, mean±standard deviation (SD) (range), 17±4 (11-24) years and 527±80 (420-660) kg. METHODS: Horses were anesthetized with sevoflurane for 60 minutes under standardized conditions for a regional limb perfusion study. In recovery, horses were administered either xylazine (200 µg kg-1) or dexmedetomidine (0.875 µg kg-1) intravenously. Recoveries were unassisted and were video-recorded for later evaluation of recovery events and quality by two individuals unaware of treatment allocation. Recovery quality was assessed using a 100 mm visual analog scale (VAS) (0=poor recovery, 100=excellent recovery), the Edinburgh Scoring System (ESS) (0-100; 100=excellent recovery) and the mean attempt interval (MAI) (longer=better). Data are mean±SD. RESULTS: All recovery quality assessments (xylazine and dexmedetomidine, respectively: VAS: 71±21 mm, 84±13 mm; ESS: 65±22, 67±30; MAI: 52±24 minutes, 60±32 minutes) and events (first limb movement: 37±8 minutes, 42±10 minutes; first attempt to lift head: 44±12 minutes, 48±9 minutes; first attempt to sternal posture: 57±28 minutes, 50±7 minutes; number of head bangs: 2.0±3.0, 0.5±0.5; time to first attempt to stand: 72±6 minutes, 78±13 minutes; time to standing: 79±14 minutes, 84±13 minutes) did not differ significantly between treatments (p>0.05). CONCLUSIONS AND CLINICAL RELEVANCE: Recovery characteristics did not differ significantly between postanesthetic xylazine and dexmedetomidine following 1 hour of sevoflurane anesthesia in horses in this study. Further evaluations in more horses and in younger horses are required to confirm these results.

Pain Management in Horses.

There has been great progress in the understanding of basic neurobiologic mechanisms of pain, but this body of knowledge has not yet translated into new and improved analgesics. Progress has been made regarding pain assessment in horses, but more work is needed until sensitive and accurate pain assessment tools are available for use in clinical practice. This review summarizes and updates the knowledge concerning the cornerstones of pain medicine (understand, assess, prevent, and treat). It highlights the importance of understanding pain mechanisms and expressions to enable a rational approach to pain assessment, prevention, and management in the equine patient.

Application of microwave-assisted extraction and ultra-high performance liquid chromatography-tandem mass spectrometry for the analysis of sex hormones and corticosteroids in sewage sludge samples.

Hormonal compounds are a concern to the international community because they can affect the aquatic biota and are therefore considered to be endocrine-disrupting compounds. These compounds have lipophilic properties, so they tend to accumulate in solid matrices, such as sewage sludge. This work presents the optimization of a microwave-assisted extraction process combined with ultra-high performance liquid chromatography-tandem mass spectrometry for the determination of 15 hormonal compounds in sludge samples. The proposed method has relative standard deviations below 23 %, good recoveries (over 71 %) for all compounds, detection limits that ranged from 1.1 to 7.9 ng g(-1) and quantification limits which ranged from 3.7 to 26.3 ng g(-1). The method was used to analyse sludge samples from four different wastewater treatment plants of Gran Canaria (Spain) with different wastewater treatments. 17ß-estradiol, 17α-ethynylestradiol, norgestrel and cortisone were detected in sludge samples at concentrations that ranged from 17.3 to 1.44 × 10(3) ng g(-1). The developed method permits the use of small quantities of sample and organic solvents, presents short extractions times and is the first one based on microwave-assisted extraction for the analysis of both sex hormones and corticosteroids.

Cardiovascular, respiratory and metabolic responses to apnea induced by atlanto-occipital intrathecal lidocaine injection in anesthetized horses.

OBJECTIVE: To determine physiologic responses to apnea-induced severe hypoxemia in anesthetized horses. STUDY DESIGN: Prospective experimental study. ANIMALS: Six university-owned horses with a median (range) body weight of 500 (220-510) kg and aged 13.5 (0.8-24.0) years scheduled for euthanasia. METHODS: Xylazine-midazolam-ketamine-anesthetized horses breathing room air spontaneously were instrumented with a facial artery catheter for pressure measurement and blood sampling, and were made apneic with atlanto-occipital intrathecal lidocaine (4 mg kg-1 ). Cardiopulmonary, biochemical and hematologic variables were recorded before (baseline) and every minute for 10 minutes after lidocaine injection. RESULTS: PaO2 values were: baseline, 55 mmHg (7.3 kPa); 1 minute, 28 mmHg (3.8 kPa); 2 minutes, 18 mmHg (2.4 kPa); 3 minutes, 15 mmHg (2.0 kPa), and 4-10 minutes, (8-11 mmHg (1.1-1.5 kPa). PaCO2 values were: baseline, 50 mmHg (6.7 kPa); 1 minute, 61 mmHg (8.1 kPa), and 2-10 minutes, 64-66 mmHg (8.5-8.8 kPa). Base excess values at baseline, 1 minute and 2-10 minutes were 5.3 mmol L-1 , 6.5 mmol L-1 and 7.0-8.1 mmol L-1 , respectively. Pulse rates at baseline, 1 minute and 2-7 minutes were 36, 53 and 54-85 beats minute-1 , respectively. Asystole occurred at 8 minutes. Pulse pressures were 50 mmHg at baseline and 1 minute, and 39 mmHg, 31 mmHg, 22 mmHg, 17 mmHg and 1-9 mmHg at 2, 3, 4, 5 and 6-10 minutes, respectively. Lactate was 0.9 mmol L-1 at baseline, progressively increasing to 1.7-2.4 mmol L-1 at 7-10 minutes. Packed cell volume increased after 7 minutes of apnea. There were no other major changes. CONCLUSIONS AND CLINICAL RELEVANCE: Apnea immediately exacerbated hypoxemia and hypercapnia and rapidly caused hemodynamic instability. Apnea in hypoxemic anesthetized horses is associated with a serious risk for progress to cardiovascular collapse.

Airway responsiveness in CD38-deficient mice in allergic airway disease: studies with bone marrow chimeras.

CD38 is a cell-surface protein involved in calcium signaling and contractility of airway smooth muscle. It has a role in normal airway responsiveness and in airway hyperresponsiveness (AHR) developed following airway exposure to IL-13 and TNF-α but appears not to be critical to airway inflammation in response to the cytokines. CD38 is also involved in T cell-mediated immune response to protein antigens. In this study, we assessed the contribution of CD38 to AHR and inflammation to two distinct allergens, ovalbumin and the epidemiologically relevant environmental fungus Alternaria. We also generated bone marrow chimeras to assess whether Cd38(+/+) inflammatory cells would restore AHR in the CD38-deficient (Cd38(-/-)) hosts following ovalbumin challenge. Results show that wild-type (WT) mice develop greater AHR to inhaled methacholine than Cd38(-/-) mice following challenge with either allergen, with comparable airway inflammation. Reciprocal bone marrow transfers did not change the native airway phenotypic differences between WT and Cd38(-/-) mice, indicating that the lower airway reactivity of Cd38(-/-) mice stems from Cd38(-/-) lung parenchymal cells. Following bone marrow transfer from either source and ovalbumin challenge, the phenotype of Cd38(-/-) hosts was partially reversed, whereas the airway phenotype of the WT hosts was preserved. Airway inflammation was similar in Cd38(-/-) and WT chimeras. These results indicate that loss of CD38 on hematopoietic cells is not sufficient to prevent AHR and that the magnitude of airway inflammation is not the predominant underlying determinant of AHR in mice.

CD38 and airway hyper-responsiveness: studies on human airway smooth muscle cells and mouse models.

Asthma is an inflammatory disease in which altered calcium regulation, contractility, and airway smooth muscle (ASM) proliferation contribute to airway hyper-responsiveness and airway wall remodeling. The enzymatic activity of CD38, a cell-surface protein expressed in human ASM cells, generates calcium mobilizing second messenger molecules such as cyclic ADP-ribose. CD38 expression in human ASM cells is augmented by cytokines (e.g., TNF-α) that requires the activation of MAP kinases and the transcription factors, NF-κB and AP-1, and is post-transcriptionally regulated by miR-140-3p and miR-708 by binding to 3' Untranslated Region of CD38 as well as by modulating the activation of signaling mechanisms involved in its regulation. Mice deficient in Cd38 exhibit reduced airway responsiveness to inhaled methacholine relative to the response in wild-type mice. Intranasal challenge of Cd38-deficient mice with TNF-α or IL-13, or the environmental fungus Alternaria alternata, causes significantly attenuated methacholine responsiveness compared with wild-type mice, with comparable airway inflammation. Reciprocal bone marrow transfer studies revealed partial restoration of airway hyper-responsiveness to inhaled methacholine in the Cd38-deficient mice. These studies provide evidence for CD38 involvement in the development of airway hyper-responsiveness; a hallmark feature of asthma. Future studies aimed at drug discovery and delivery targeting CD38 expression and (or) activity are warranted.

Molecularly imprinted solid-phase extraction coupled with ultra high performance liquid chromatography and fluorescence detection for the determination of estrogens and their metabolites in wastewater.

Estrogens are an important class of endocrine-disrupting compounds, and their contamination of environmental waters through the effluents of wastewater treatment plants could have an important impact on aquatic biota, even at low concentrations. For this reason, the development of selective and sensitive extraction methodologies, which permit the identification and quantification of these compounds at trace level concentrations, is very important. In this study, a quantitative method based on molecularly imprinted solid phase extraction coupled to ultra high performance liquid chromatography with fluorescence detection has been developed. It has been used for the simultaneous determination of three estrogens and two of their metabolites in water samples from wastewater treatment plants. The method developed presents satisfactory limits of detection (between 0.18 and 0.45 ng·mL-1 ), good recoveries (higher than 60%) and low relative standard deviations (under 10%). The method was used to analyze wastewater from a veterinary hospital as well as influent and effluent samples of a wastewater treatment plant of Gran Canaria (Spain) The concentrations of the detected hormones ranged from 1.35 to 2.57 ng·mL-1 .

Radiation dermatitis in the hairless mouse model mimics human radiation dermatitis.

Over half of all people diagnosed with cancer receive radiation therapy. Moderate to severe radiation dermatitis occurs in most human radiation patients, causing pain, aesthetic distress, and a negative impact on tumor control. No effective prevention or treatment for radiation dermatitis exists. The lack of well-characterized, clinically relevant animal models of human radiation dermatitis contributes to the absence of strategies to mitigate radiation dermatitis. Here, we establish and characterize a hairless SKH-1 mouse model of human radiation dermatitis by correlating temporal stages of clinical and pathological skin injury. We demonstrate that a single ionizing radiation treatment of 30 Gy using 6 MeV electrons induces severe clinical grade 3 peak toxicity at 12 days, defined by marked erythema, desquamation and partial ulceration, with resolution occurring by 25 days. Histopathology reveals that radiation-induced skin injury features temporally unique inflammatory changes. Upregulation of epidermal and dermal TGF-ß1 and COX-2 protein expression occurs at peak dermatitis, with sustained epidermal TGF-ß1 expression beyond resolution. Specific histopathological variables that remain substantially high at peak toxicity and early clinical resolution, including epidermal thickening, hyperkeratosis and dermal fibroplasia/fibrosis, serve as specific measurable parameters for in vivo interventional preclinical studies that seek to mitigate radiation-induced skin injury.

Evaluation of preoperative intraperitoneal injection of bupivacaine for intraoperative antinociception in cats undergoing ovariohysterectomy: A randomized clinical trial.

OBJECTIVE: To determine if preoperative intraperitoneal bupivacaine can minimize intra- and postoperative nociception/pain in cats undergoing ovariohysterectomy. STUDY DESIGN: Prospective, randomized, investigator-blinded, placebo-controlled clinical trial. ANIMALS: Forty-seven, intact female cats. METHODS: Cats were anesthetized using a standard protocol and randomized to receive ultrasound-guided intraperitoneal 0.9 % saline (US-S) or 0.25 % bupivacaine (US-IPLA) before ovariohysterectomy. On recovery, US-S cats received 2 mg/kg robenacoxib subcutaneously and US-IPLA cats received equivalent volume of 0.9 % saline subcutaneously. Intraoperative outcome variables included heart rate (HR), respiratory rate (fR), systolic arterial pressure (SAP), and vaporizer setting associated with relevant surgical events characterized by manipulation of each ovarian pedicle (OP1, OP2) and the uterine body (UB). The postoperative outcome variable was need for rescue analgesia, determined using the Glasgow Composite Measure Pain Scale during 6 h after tracheal extubation. Intraoperative data were analyzed using two-way ANOVA and Sidák's multiple comparisons test. The probability of postoperative rescue analgesia was analyzed using the Gehan-Breslow-Wilcoxon test. Significance was p < 0.05. RESULTS: Compared to baseline, all surgical events caused significant increases in HR and SAP in both groups, fR increased in US-IPLA but not in US-S, vaporizer settings remained unchanged during OP1, OP2 and UB in group US-IPLA, and were significantly higher only during OP1 in group US-S. There were no significant between-group differences in intraoperative variables and postoperative need for rescue analgesia. CONCLUSIONS AND CLINICAL RELEVANCE: Preoperative intraperitoneal bupivacaine had minimal effects on intraoperative indicators of nociception. The need for rescue analgesia was not significantly different between groups.