Clinical Sciences

Objective: To establish normal parameters of thromboelastography (TEG) in healthy adult cats. Background: Thromboelastography (TEG) is an in vitro test of coagulation that has been shown to be useful in humans, dogs and select species to identify and quantify alterations of hemostasis (e.g., hypercoagulable and hypocoagulable states). It has also been demonstrated to be useful in monitoring effects of anticoagulant therapies. This test has not been evaluated in cats. Methods: Blood was collected from 25 clinically normal cats by venipuncture using a 21 gauge  3 1/2 inch butterfly catheter and syringe for medial saphenous or jugular venipuncture. A single 1.8 mL sample in 3.8% Sodium Citrate (9:1) was collected from each cat. Recalcified whole blood was analyzed 30 minutes following collection with the TEG s 5000 analyzer (Haemoscope, Niles, IL). Analysis temperature was 37.6 1C. TEG parameters recorded included: R-value (represents initial fibrin formation), K (time from R to standard fixed measure of clot firmness which represents contributions of platelets and fibrinogen), maximum amplitude (MA; represents absolute clot strength), and alpha angle (a; the slope of TEG tracing which represents rate of clot formation). The coagulation index (CI) was derived from the formula generated for humans to provide an overall assessment of whether the sample was hyper-or hypocoagulable. Results: Values for the 25 normal cat samples are reported as mean AE 2 standard deviations. R 5 2.97; 1.23-4.72; K 5 1.54, 0.38-2.71; a 5 70.70, 57.76-83.65; MA 5 58.50, 45.26-71.74 and CI 5 2.27, 0.07-4.46. Compared to historical information obtained on normal dogs, cats have significantly shorter R and K and larger a, MA and CI. Conclusions: TEG does have reproducible performance when used to evaluate coagulation status in normal cats. Compared to dogs, normal cats favor a hypercoagulable state. Species-specific normal values are necessary for interpretation of TEG results. This test bears potential value for use in future experimental and clinical work to investigate hemostasis in cats receiving anticoagulant therapies or in cats suffering from diseases such as cardiomyopathy which are thought to be associated with altered coagulation status.

& The authors explored the relative utility of pulmonary function tests (PFTs) and computed tomography (CT) to characterize the progression of papain induced emphysema in sheep (n ¼ 12). PFT included plethysmography (FRC pleth ), helium dilution (FRC He ), and expired reserve volume (ERV). Following papain, FRC pleth and FRC He were unchanged; ERV decreased hence residual volume increased significantly (RV þ270 mL, þ86%, P ¼ :02). In contrast, FRC by CT increased in 10 of 12 sheep (þ264 mL, þ21%, P ¼ :008). We conclude that plethysmography was insensitive to emphysema, but the effect on ERV (i.e., trapped gas volume) and FRC by CT were very similar, and in line with the morphologic changes in this animal model.

Objective: To establish normal parameters of thromboelastography (TEG) in healthy adult cats. Background: Thromboelastography (TEG) is an in vitro test of coagulation that has been shown to be useful in humans, dogs and select species to identify and quantify alterations of hemostasis (e.g., hypercoagulable and hypocoagulable states). It has also been demonstrated to be useful in monitoring effects of anticoagulant therapies. This test has not been evaluated in cats. Methods: Blood was collected from 25 clinically normal cats by venipuncture using a 21 gauge  3 1/2 inch butterfly catheter and syringe for medial saphenous or jugular venipuncture. A single 1.8 mL sample in 3.8% Sodium Citrate (9:1) was collected from each cat. Recalcified whole blood was analyzed 30 minutes following collection with the TEG s 5000 analyzer (Haemoscope, Niles, IL). Analysis temperature was 37.6 1C. TEG parameters recorded included: R-value (represents initial fibrin formation), K (time from R to standard fixed measure of clot firmness which represents contributions of platelets and fibrinogen), maximum amplitude (MA; represents absolute clot strength), and alpha angle (a; the slope of TEG tracing which represents rate of clot formation). The coagulation index (CI) was derived from the formula generated for humans to provide an overall assessment of whether the sample was hyper-or hypocoagulable. Results: Values for the 25 normal cat samples are reported as mean AE 2 standard deviations. R 5 2.97; 1.23-4.72; K 5 1.54, 0.38-2.71; a 5 70.70, 57.76-83.65; MA 5 58.50, 45.26-71.74 and CI 5 2.27, 0.07-4.46. Compared to historical information obtained on normal dogs, cats have significantly shorter R and K and larger a, MA and CI. Conclusions: TEG does have reproducible performance when used to evaluate coagulation status in normal cats. Compared to dogs, normal cats favor a hypercoagulable state. Species-specific normal values are necessary for interpretation of TEG results. This test bears potential value for use in future experimental and clinical work to investigate hemostasis in cats receiving anticoagulant therapies or in cats suffering from diseases such as cardiomyopathy which are thought to be associated with altered coagulation status.

& The authors explored the relative utility of pulmonary function tests (PFTs) and computed tomography (CT) to characterize the progression of papain induced emphysema in sheep (n ¼ 12). PFT included plethysmography (FRC pleth ), helium dilution (FRC He ), and expired reserve volume (ERV). Following papain, FRC pleth and FRC He were unchanged; ERV decreased hence residual volume increased significantly (RV þ270 mL, þ86%, P ¼ :02). In contrast, FRC by CT increased in 10 of 12 sheep (þ264 mL, þ21%, P ¼ :008). We conclude that plethysmography was insensitive to emphysema, but the effect on ERV (i.e., trapped gas volume) and FRC by CT were very similar, and in line with the morphologic changes in this animal model.

Organ regeneration in mammals is hypothesized to require a functional pool of stem or progenitor cells, but the role of these cells in lung regeneration is unknown. Whereas postnatal regeneration of alveolar tissue has been attributed to type II alveolar epithelial cells (AECII), we reasoned that bronchioalveolar stem cells (BASCs) have the potential to contribute substantially to this process. To test this hypothesis, unilateral pneumonectomy (PNX) was performed on adult female C57/BL6 mice to stimulate compensatory lung regrowth. The density of BASCs and AECII, and morphometric and physiologic measurements were recorded on days 1, 3, 7, 14, 28, and 45 days after surgery. Vital capacity was restored by day 7 after PNX. BASC numbers increased by day 3, peaked to 220% of controls (P<0.05) by day 14, then returned to baseline after active lung regrowth was complete, whereas AECII cell densities increased to 124% of baseline (N/S). Proliferation studies revealed significant BrdU uptake in BASCs and AECII within the first 7 days after PNX. Quantitative analysis using a systems biology model was used to evaluate the potential contribution of BASCs and AECII. The model demonstrated that BASC proliferation and differentiation contributes between 0 and 25% of compensatory alveolar epithelial (type I and II cell) regrowth, demonstrating that regeneration requires a substantial contribution from AECII. The observed cell kinetic profiles can be reconciled using a dual-compartment (BASC and AECII) proliferation model assuming a linear hierarchy of BASCs, AECII and AECI cells to achieve lung regrowth.

Energetic cost of breathing, body composition, and pulmonary function in horses with recurrent airway obstruction. .-This study was conducted to determine whether horses with naturally occurring, severe chronic recurrent airway obstruction (RAO) 1) have a greater resting energy expenditure (REE) than control horses, 2) suffer body mass depletion, and 3) have significantly decreased REE after bronchodilation and, therefore, also 4) whether increased work of breathing contributes to the cachexia seen in some horses with RAO. Six RAO horses and six control horses underwent indirect calorimetric measures of REE and pulmonary function testing using the esophageal balloon-pneumotachograph method before and after treatment with ipratropium bromide, a parasympatholytic bronchodilator agent, at 4-h intervals for a 24-h period. Body condition scoring was performed, and an estimate of fat mass was determined via B-mode ultrasonography. O 2 and CO2 fractions, respiratory airflow, respiratory rate, and pleural pressure changes were recorded, and O 2 consumption, CO 2 production, REE, pulmonary resistance, dynamic elastance, and tidal volume were calculated. In addition, we performed lung function testing and calorimetry both before and after sedation in two control horses. RAO horses had significantly lower body condition scores (2.8 Ϯ 1.0 vs. 6.4 Ϯ 1.2) and significantly greater O 2 consumption than controls (4.93 Ϯ 1.30 vs. 2.93 Ϯ 0.70 ml ⅐ kg Ϫ1 ⅐ min Ϫ1 ). After bronchodilation, there was no significant difference in O 2 consumption between RAO horses and controls, although there remained evidence of residual airway obstruction. There was a strong correlation between O 2 consumption and indexes of airway obstruction. Xylazine sedation was not associated with changes in pulmonary function but did result in markedly decreased REE in controls. indirect calorimetry; naturally occurring disease; resting energy expenditure; oxygen consumption; ipratropium bromide Address for reprint requests and other correspondence: M. R. Mazan,

as measured by changes in segmental compliance, which increased 267%. Conclusions: Collateral ventilation is significantly increased in sheep following nebulized papain. Bronchoscopic measurement of collateral ventilation may be useful for evaluating other animal models of emphysema and for predicting the response to bronchoscopic therapies in human emphysema patients.

Background: Adult mice have a remarkable capacity to regenerate functional alveoli following either lung resection or injury that exceeds the regenerative capacity observed in larger adult mammals. The molecular basis for this unique capability in mice is largely unknown. We examined the transcriptomic responses to single lung pneumonectomy in adult mice in order to elucidate prospective molecular signaling mechanisms used in this species during lung regeneration.

Background: The objective of this study was to examine the relationship between chronic cough, pulmonary mechanical function, bronchial hyper-responsiveness, and peripheral airway inflammation in adult performance horses with nonseptic inflammatory airway disease (IAD).Hypothesis: We hypothesized that horses with a presenting complaint of cough have a higher percentage of inflammatory cells on bronchoalveolar lavage (BAL), greater airway obstruction, and airway hyper-responsiveness (AHR) than do horses without cough.Animals/Sample Population: Adult performance horses (n = 137) referred for evaluation of signs of IAD including cough or exercise intolerance (university hospital patients) and BAL samples (n = 142) taken in first opinion practice.Methods: A descriptive, retrospective cohort analysis was performed to evaluate the association between chronic cough and pulmonary mechanical function, AHR, BAL cytology, patient signalment, and comorbid features (multivariable logistic regression).Results: Cough was significantly more prevalent in horses >7 years, and best characterized by a high BAL neutrophil count (>5%) and nasal discharge. Lung function mechanics, abnormal thoracic auscultation, and exercise intolerance did not retain statistical significance in the logistical regression analysis of cough. Although AHR was not related to neutrophilic airway inflammation (BAL neutrophils >5%), it was significantly associated with BAL mast cells >2%.Conclusions and Clinical Importance: Our data support that neutrophilic airway inflammation may potentiate cough without further changing respiratory mechanical function in IAD. In contrast, mast cell release increased AHR without affecting the incidence of cough. Cough may be used as an indicator of neutrophilic airway inflammation in the presence of low-grade nonseptic respiratory disease.

It is almost universally accepted that respiratory disease can limit athletic performance. Because of significant respiratory reserve capacity, horses can often compete successfully in low-level competitions or during recreation even with considerable inflammatory changes within the lungs. However, such lung changes can reduce maximal aerobic exercise and have considerable impact on those horses competing in upper-level events or as racehorses. Clinical observations and physical examination findings related to the respiratory system often do not clearly indicate disease; therefore, ancillary tests are frequently required to adequately diagnose inflammatory airway dysfunction. This review will detail techniques that can provide useful diagnostic information regarding pulmonary function and outline suitable treatment modalities.

Reasons for performing study: Diagnosis of inflammatory airway disease (IAD) currently rests upon the results of bronchoalveolar lavage (BAL) cytology, lung function testing and histamine bronchoprovocation (HBP), none of which provides direct information about structural change in the lung.Hypothesis: That thoracic radiography might better portray structural change in the lungs and therefore offer a good clinical assessment of IAD.Methods: A radiographic scoring system was developed to assess the extent of bronchial and interstitial pattern on thoracic radiographs in the dorsocaudal, dorsocranial and caudoventral regions in 16 control horses and 33 horses with IAD. Mean scores were compared to ascertain whether thoracic radiographs could distinguish between the 2 groups. In order to determine whether independent observers reliably scored radiographs similarly, an inter-rater reliability score was employed for each radiographic observation. Correlations between radiographic scores, BAL cytology, lung function testing using the forced oscillatory technique and HBP were examined.Results: Inter-rater reliability was only moderate. Radiographic scoring demonstrated no differences between the 2 groups. There were no correlations among BAL cytology, lung function testing, HBP and radiographic scores.Conclusions and potential relevance: Thoracic radiographs are a low-yield diagnostic modality in horses with a clinical history compatible with IAD. In the absence of clinical evidence of more extensive, infectious disease, thoracic radiographs neither refine nor improve diagnosis of IAD, but increase diagnostic costs.

Inflammatory airway disease (IAD) in horses, similar to asthma in humans, is a common cause of chronic poor respiratory health and exercise intolerance due to airway inflammation and exaggerated airway constrictive responses. Human rhinovirus is an important trigger for the development of asthma; a similar role for viral respiratory disease in equine IAD has not been established yet. In a case-control study, horses with IAD (n = 24) were compared to control animals from comparable stabling environments (n = 14). Horses were classified using pulmonary function testing and bronchoalveolar lavage. PCR for equine rhinitis virus A and B (ERAV, ERBV), influenza virus (EIV), and herpesviruses 2, 4, and 5 (EHV-2, EHV-4, EHV-5) was performed on nasal swab, buffy coat from whole blood, and cells from BAL fluid (BALF), and serology were performed. Categorical variables were compared between IAD and control using Fisher&#39;s exact test; continuous variables were compared with an independent t-...

Autologous lung-derived mesenchymal stem cells (LMSCs) were transplanted endoscopically into sheep with experimental emphysema to assess their capacity to regenerate functional tissue. LMSC lines were derived from transbronchial biopsies, cloned at passage 2, expanded in culture, and labeled. A delivery scaffold containing 1% fibrinogen, 20 μg/ml of fibronectin, and 20 μg/ml of poly-L-lysine was used to promote cell attachment and spreading. Treatment animals received scaffold containing 5–10 × 106 cells/site; control animals received scaffold alone. Phenotypic markers, differentiation capacity, extracellular matrix protein expression, and paracrine function of LMSCs were characterized in vitro. Responses to LMSC transplantation in vivo were assessed in terms of clinical toxicity, lung physiology, change in tissue mass (measured by CT scanning) and perfusion (measured by scintigraphy scanning), and tissue histology. At 4-week follow-up, transplants were well tolerated and associated...

While multipotent mesenchymal stromal cells have been recently isolated from adult lung (L-MSCs), there is very limited data on their biological properties and therapeutic potential in vivo. How L-MSCs compare with bone marrow-derived MSCs (BM-MSCs) is also unclear. In this study, we characterized L-MSC phenotype, clonogenicity, and differentiation potential, and compared L-MSCs to BM-MSCs in vivo survival, retention, paracrine gene expression, and repair or elastase injury after transplantation. L-MSCs were highly clonogenic, frequently expressed aldehyde dehydrogenase activity, and differentiated into osteocytes, chondrocytes, adipocytes, myofibroblasts, and smooth muscle cells. After intravenous injection (2 h), L-MSCs showed greater survival than BM-MSCs; similarly, L-MSCs were significantly more resistant than BM-MSCs to anchorage independent culture (4 h) in vitro. Long after transplantation (4 or 32 days), a significantly higher number of CD45 neg L-MSCs were retained than BM-MSCs. By flow cytometry, L-MSCs expressed more intercellular adhesion molecule-1 (ICAM-1), platelet derived growth factor receptor alpha (PDGFRa), and integrin a2 than BM-MSCs; these proteins were found to modulate endothelial adherence, directional migration, and migration across Matrigel in L-MSCs. Further, L-MSCs with low ICAM-1 showed poorer lung retention and higher phagocytosis in vivo. Compared with BM-MSCs, L-MSCs expressed higher levels of several transcripts (e.g., Ccl2, Cxcl2, Cxcl10, IL-6, IL-11, Hgf, and Igf2) in vitro, although gene expression in vivo was increased by L-MSCs and BM-MSCs equivalently. Accordingly, both L-MSCs and BM-MSCs reduced elastase injury to the same extent. This study demonstrates that tissuespecific L-MSCs possess mechanisms that enhance their lung retention after intravenous transplantation, and produce substantial healing of elastase injury comparable to BM-MSCs.

AST aspartate aminotransferase BPM beats per minute CK creatine kinase CSVM Cummings School of Veterinary Medicine EGA equine granulocytic anaplasmosis F fahrenheit GGT gamma-glutamyl transpeptidase PCR polymerase chain reaction RR reference range SCID severe combined immunodeficiency disease

The way that we house and exercise our horses, especially in non-temperate climates such as New England, is well entrenched in the equine culture. It may conserve space to store hay overhead, it may be economically favorable and more comfortable to have the indoor arena attached to the main barn, and it may make us more comfortable to close up our barns in the winter, but this management style results in high organic dust and endotoxin exposure for our horses. This dust exposure results in exacerbation of signs in horses with recurrent airway obstruction (RAO) and is also strongly associated with inflammatory airway diseases (IADs). Organic dust exposure has been shown to result in long-term declines in respiratory function and increased prevalence of chronic lung diseases in humans—it is logical to expect that the same exposures will have similar effects on equine respiratory health. We believe that it is important to decrease this exposure to both horses and people in equine barns...