Dog Lung Research Articles

Proteomic change in the upper lobe of the left lung of Beagle dogs at the lung migration stage of Toxocara canis infection

BackgroundToxocara canis is considered one of the most neglected parasitic zoonoses and threatens the health of millions of people worldwide with a predilection for pediatric and adolescent populations in impoverished communities. Exploring the invasion and developmental mechanisms associated with T. canis infection in its definitive canine hosts will help to better control zoonotic toxocariasis.MethodsProteomic changes in samples from the upper lobe of the left lung of Beagle puppies were systematically analyzed by quantitative proteomic technology of data-independent acquisition (DIA) at 96 h post-infection (hpi) with T. canis. Proteins with P-values < 0.05 and fold change > 1.5 or < 0.67 were considered proteins with differential abundance (PDAs).ResultsA total of 28 downregulated PDAs and 407 upregulated PDAs were identified at 96 hpi, including RhoC, TM4SFs and LPCAT1, which could be associated with the maintenance and repair of lung homeostasis. GO annotation and KEGG pathway enrichment analyses of all identified proteins and PDAs revealed that many lung proteins have correlation to signal transduction, lipid metabolism and immune system.ConclusionsThe present study revealed lung proteomic alterations in Beagle dogs at the lung migration stage of T. canis infection and identified many PDAs of Beagle dog lung, which may play important roles in the pathogenesis of toxocariasis, warranting further experimental validation.Graphical

Canine Visceral Leishmaniasis: A Histological and Immunohistochemical Study of Fibropoiesis in Chronic Interstitial Pneumonitis.

We studied some fibrotic aspects of chronic interstitial pneumonitis in the lungs of dogs infected with Leishmania infantum. The lungs of eleven naturally infected dogs, twelve experimentally infected with two distinct strains of L. infantum (BH401 and BH46), and six uninfected (controls) dogs, were analyzed by histological, parasitological, and immunohistochemical studies. Conventional histology (HE), collagen deposition (Gomori's silver staining for reticulin collagen fibers), and immunohistochemistry for myofibroblast characterization were carried out based on the cellular expression of alpha-smooth muscle actin, vimentin, cytokeratin, E-cadherin, snail antigen homologue 1 (SNAI1) (Snail), and the cytokine expression of transforming growth factor-beta (TGF-β). Parasitological screening was carried out using conventional polymerase chain reaction (PCR) and the immunohistochemical reaction of streptavidin-peroxidase for visualizing Leishmania amastigotes. Dogs naturally infected with L. infantum and experimentally infected with L. infantum BH401 strains showed intense interstitial pneumonitis characterized by thickening of the alveolar septa as a consequence of an intense diffuse and focal (plaques) chronic exudate of mononuclear cells associated with fibrogenesis. The expression of alpha-actin, vimentin, and TGF-β was higher in the lung interstitium of all infected dogs than in the other two groups (BH46 strain and controls). Moreover, in both the naturally and experimentally infected dog (BH401 strain) groups, the expression of Snail was moderate to intense in contrast to the other groups. Based on these immunohistochemical results, we concluded that mesenchymal cells are active in promoting changes in the extracellular matrix in the lungs of dogs naturally and experimentally infected with L. infantum, but it depends on the virulence of the parasite.

Intravascular papillary endothelial hyperplasia in the lungs of a wild Korean raccoon dog.

A male Korean raccoon dog of unknown age was rescued and placed at the Daejeon Wildlife Rescue Center, Korea. Physical examination revealed severe emaciation and dehydration, as well as thick crusts and alopecia over most of the body. During medical care, the animal died and was submitted for postmortem examination. Firm, brown-red lesions of various sizes were observed on the surface of the lungs. In cross-sections of the lungs, pulmonary vessels were thickened and dilated, with white irregular papillary luminal projections. Histologically, pulmonary blood vessels were severely hyperplastic, characterized by thickened dilated walls and fibrous papillary projections covered with a single layer of endothelial cells (ECs). Hyperplastic fibrous connective tissue was confirmed by Masson trichrome staining. The ECs expressed CD31. We diagnosed the lesion as intravascular papillary endothelial hyperplasia, a unique non-neoplastic reactive process that has not been reported previously in pulmonary vessels of canids, equids, or felids, to our knowledge.

Natural SARS-CoV-2 infection in dogs: Determination of viral loads, distributions, localizations, and pathology

Instances of reverse zoonosis involving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been documented in both controlled experiments and spontaneous cases. Although dogs are susceptible to infection, clinical significance is limited to mild or asymptomatic. Here, we investigate the fatal cases of natural SARS-CoV-2 infection in dogs in Thailand. Pathological findings of SARS-CoV-2-infected dogs reveal severe diffuse alveolar damage, pulmonary hyalinization and fibrosis, and syncytial formation, together with minor lesions in brain and kidney. Employing reverse transcription–digital PCR, substantial viral loads of SARS-CoV-2 were detected in lung, kidney, brain, trachea, tonsil, tracheobronchial lymph node, liver, and intestine, respectively. Localization of SARS-CoV-2 within various tissues was examined through immunohistochemistry (IHC), where the co-localization of the viral spike protein and the angiotensin-converting enzyme 2 (ACE2) receptor was illustrated using double IHC. SARS-CoV-2 localization was markedly identified in the epithelial cells of the lung, trachea, intestine and kidneys, and moderately presented in the salivary gland and gall bladder, where the co-localization with the ACE2 was also evident. Neurons in the brainstem where exhibited lymphocytic perivascular cuffing were also found to be positive for SARS-CoV-2 in IHC testing, despite lacking ACE2 receptor expression. In addition, SARS-CoV-2 replication within the lungs of infected dogs was confirmed by transmission electron microscopy, visualizing free viral particles within the cytosol or the endoplasmic reticulum of syncytial cells within the lung. This study considerably expanded on the knowledge of the pathology associated with natural SARS-CoV-2 infection in dogs, a scenario that is relatively infrequent but occasionally leads to fatal outcome. Furthermore, these findings suggest the potential utility of dogs as a model for studying SARS-CoV-2 infection in humans, warranting further investigation.

Morphology, organo- and histometric features of the heart and lungs of a sexually mature domestic dog (Canis Lupus Familiaris L., 1758)

The cardiovascular system and respiratory organs in animals are interconnected, they perform extremely important functions for the vital activity of the organism, the main of which is gas exchange. Therefore, the study of the cardiovascular system and respiratory organs is an urgent issue of the present. The aim of the study was to morphologically evaluate the macro- and histological structures of the heart and lungs of the domestic dog. Comprehensive morphological methods of research were used: histological, anatomical, organ, histo-, cytometric, and statistical, which provided new data on the peculiarities of macro-, histo-, and cytomorphometric characteristics of the morphological structures of the heart and lungs. The dog heart has a rounded shape, its absolute weight is 167.58±9.46 g (without epicardial fat – 154.22±8.04 g), relative weight – 0.72±0.005%. It was found that cardiomyocytes of the left ventricle had the largest volume, the right ventricle – the smallest, and atrial cardiomyocytes – the smallest. At the same time, the nuclearcytoplasmic ratio of cardiomyocytes of the left ventricle is 0.0224±0.0076, the cardiomyocytes of the right ventricle have a greater value – 0.0275±0.0081 and the atrial cardiomyocytes have the highest value – 0.0367±0.0105. Such ambiguous cytometric parameters of cardiomyocytes are associated with the morphological and functional activity of the myocardial ventricular muscle tissue and its functional features inherent in spontaneous and rhythmic contractions, which result in blood flow through a closed system of vessels. The absolute weight of the domestic dog’s lungs is 201.3±18.4 g, the relative weight is 1.21±0.14%, the ratio of the absolute weight of the left to the right lung is 1:1.33. According to the asymmetry coefficient (1.37:1), the lungs of dogs are of the narrowed-elongated type. The connective tissue stroma of the lungs occupies 59.62±3.4%, the respiratory part – 40.38±2.6%. The data on the morphology of the heart and lungs of the domestic dog, including the results of the study of the macro- and microscopic structure of the organs under investigation, which are presented in the publication, are of great importance for histology and comparative anatomy, and also make a significant contribution to clinical veterinary medicine

Experimental infection and co-infection with Chinese strains of Ehrlichia canis and Babesia vogeli in intact and splenectomized dogs: Insights on clinical, hematologic and treatment responses

Animal infection models are crucial for studying various aspects of Ehrlichia canis infections. To understand the pathogenesis of the first Chinese isolate of E. canis and simulate the natural progression of canine ehrlichiosis, we developed a model with 18 Beagle dogs that consisted of E. canis initial infection (days 0–17), treatment with doxycycline or rifampicin (days 18–32), recovery (days 33–66), E. canis reinfection (days 67–91), and Babesia vogeli superinfection (days 92–116). We measured body weight and rectal temperature every other day, drew blood every 4 days for routine hematology and biochemistry tests, and for quantification of E. canis and B. vogeli by quantitative PCRs. In this study, the first isolate of E. canis from China was used to experimentally infect dogs, and the infected dogs exhibited clinical signs of acute severe ehrlichiosis, including high fever, loss of appetite, dehydration, and body weight loss, confirming the similar pathogenicity of E. canis in China as compared to isolates from other regions. Infection with E. canis and B. vogeli led to reduced body weight and fever in dogs. Doxycycline treatment led to absence of E. canis DNA in infected dogs, while rifampicin treatment lowered the blood E. canis copy number up to 1.5 folds. E. canis-free infected dogs after doxycycline treatment were successfully re-infected with E. canis, indicating dogs with antibodies are still at risk of re-infection. Super-infection with B. vogeli resulted in higher fever, more severe anemia, and a reduced number of platelets. Splenectomized dogs showed significantly higher E. canis numbers during recovery and re-infection than intact dogs. The histological changes were observed in brain, lung, kidney, liver and spleen of the infected dogs. The findings in this study provide insights into clinical and hematologic responses, as well as effective treatment options, for dogs infected with the first Chinese isolate of E. canis, and may contribute to our understanding of the diagnosis and prevention of tick-borne diseases in dogs, including canine monocytic ehrlichiosis.

Arterial blood vessels of the lung of the Russian hound breed dogs in the age aspect

Such a breed of dog as the Russian Hound is the most popular breed among hounds in Russia. The average weight is 25 -35 kg, and at the withers it reaches up to 65 cm, representatives of this breed live up to 14-16 years. They are easily trained and are ideal hunting companions for hare and fox, during which they often suffer injuries in the chest cavity, and veterinarians face the difficult task of providing surgical care to such patients. Knowledge of the anatomical and topographic features of the arterial bed of the lungs is necessary when providing surgical care. During the formation of the functional activity of the body, the change in the diameter of the arterial bed is of particular interest. The purpose of the study was to study the arterial bed of the lungs of the Russian Hound breed in the age aspect, to give the arteries a morphometric characteristic. Three age groups of dogs were selected for the study: newborn puppies, puppies at the age of nine months, and mature dogs. Fine anatomical preparation, vasorentgenography, morphometry was chosen as research methods. During the study, morphometric data of such vessels as: pulmonary trunk, right and left pulmonary arteries, right and left bronchial arteries were obtained.

Derivation of a new model of lung adenocarcinoma using canine lung cancer organoids for translational research in pulmonary medicine

Canine primary lung cancer (cPLC) is a rare malignant tumor in dogs, and exhibits poor prognosis. Effective therapeutic drugs against cPLC have not been established yet. Also, cPLC resembles human lung cancer in histopathological characteristics and gene expression profiles and thus could be an important research model for this disease. Three-dimensional organoid culture is known to recapitulate the tissue dynamics in vivo. We, therefore, tried to generate cPLC organoids (cPLCO) for analyzing the profiles of cPLC. After samples from cPLC and the corresponding normal lung tissue were collected, cPLCO were successfully generated, which recapitulated the tissue architecture of cPLC, expressed lung adenocarcinoma marker (TTF1), and exhibited tumorigenesis in vivo. The sensitivity of cPLCO to anti-cancer drugs was different among strains. RNA-sequencing analysis showed significantly upregulated 11 genes in cPLCO compared with canine normal lung organoids (cNLO). Moreover, cPLCO were enriched with the MEK-signaling pathway compared with cNLO. The MEK inhibitor, trametinib decreased the viability of several strains of cPLCO and inhibited the growth of cPLC xenografts. Collectively, our established cPLCO model might be a useful tool for identifying novel biomarkers for cPLC and a new research model for dog and human lung cancer.

Characterization of the pathogenicity of extraintestinal pathogenic Escherichia coli isolates from pneumonia-infected lung samples of dogs and cats in South Korea

This study aimed to investigate the pathogenicity of extraintestinal pathogenic Escherichia coli (ExPEC) isolated from dog and cat lung samples in South Korea. A total of 101 E. coli isolates were analyzed for virulence factors, phylogroups, and O-serogroups, and their correlation with bacterial pneumonia-induced mortality was elucidated. P fimbriae structural subunit (papA), hemolysin D (hlyD), and cytotoxic necrotizing factor 1 (cnf1) were highly prevalent in both species, indicating correlation with bacterial pneumonia. Phylogroups B1 and B2 were the most prevalent phylogroups (36.6% and 32.7%, respectively) and associated with high bacterial pneumonia-induced mortality rates. Isolates from both species belonging to phylogroup B2 showed high frequency of papA, hlyD, and cnf1. O-serogrouping revealed 21 and 15 serogroups in dogs and cats, respectively. In dogs, O88 was the most prevalent serogroup (n = 8), and the frequency of virulence factors was high for O4 and O6. In cats, O4 was the most prevalent serogroup (n = 6), and the frequency of virulence factors was high for O4 and O6. O4 and O6 serogroups were mainly grouped under phylogroup B2 and associated with high bacterial pneumonia-induced mortality. This study characterized the pathogenicity of ExPEC and described the probability of ExPEC pneumonia-induced mortality.

Lung Lipidomic Alterations in Beagle Dogs Infected with Toxocara canis.

Toxocariasis, mainly caused by Toxocara canis, and to a lesser extent, Toxocara cati, is a neglected parasitic zoonosis. The mechanisms that underlie the changes in lipid metabolism of T. canis infection in Beagle dogs' lungs remain unclear. Lipidomics is a rapidly emerging approach that enables the global profiling of lipid composition by mass spectrometry. In this study, we performed a non-targeted lipidomic analysis of the lungs of Beagle dogs infected with the roundworm T. canis using liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 1197 lipid species were identified, of which 63, 88, and 157 lipid species were significantly altered at 24 h post-infection (hpi), 96 hpi, and 36 days post-infection (dpi), respectively. This global lipidomic profiling identified infection-specific lipid signatures for lung toxocariasis, and represented a comprehensive comparison between the lipid composition of dogs' lungs in the presence and absence of T. canis infection. The potential roles of the identified lipid species in the pathogenesis of T. canis are discussed, which has important implications for better understanding the interaction mechanism between T. canis and the host lung.

A pilot study on the lung morphology of shelter dogs in relation to air pollution in Trinidad.

To identify and characterize the gross and histological lesions associated with air pollution in the lungs of dogs from various locations in Trinidad. 56 fresh lungs were obtained from already euthanized adult dogs collected from different locations in Trinidad at the Trinidad and Tobago Society for the Prevention of Cruelty to Animals. Lung specimens were examined grossly and tissue samples were taken for routine histologic examination. Histological examination showed that 51.8% of the dogs had evidence of anthracosis. Dogs with anthracosis had greater median lesion scores compared to dogs without anthracosis (P = .022). There was no association between the presence of anthracosis and any other lesion in this study (P > .05). There was evidence that dogs with anthracosis had a greater degree of nonspecific lung histologic lesions. Using the dog as a sentinel model for human exposure in Trinidad, our findings indicate that environmental air pollution may also have an effect on the respiratory health of the human population. It is important for the public to be aware of air pollution, and the government of Trinidad and Tobago should develop an intervention protocol along with veterinary and human medical epidemiologists to reduce air pollution in the country.

Investigation of Genes and Proteins Expression Associating Serotonin Signaling Pathway in Lung and Pulmonary Artery Tissues of Dogs with Pulmonary Hypertension Secondary to Degenerative Mitral Valve Disease: The Preliminary Study.

Simple SummaryPulmonary hypertension is an unusual elevation of the blood pressure in pulmonary circulation. In dogs, pulmonary hypertension is commonly occurred as a complication of progressive degenerative mitral valve disease especially in senior small-breed dogs. Previous studies revealed that the serotonin signaling pathway is associated with the pathogenesis of pulmonary hypertension. However, research in dogs was scarce. Therefore, the present study aimed to illustrate the understanding of this point by assessing the expression of the targeted genes and proteins related to the serotonin pathway in lung tissues and pulmonary arteries of dogs. Our results showed that the pattern of gene and protein expression was different in canine lung and pulmonary arteries. The targeted proteins in pulmonary artery tissues of the degenerative mitral valve disease dogs with and without pulmonary hypertension tended to be upregulated. In addition, the expression of these protein was increased in the pneumocytes of the alveolar walls, pulmonary alveolar macrophages, and bronchial epithelial cells. A correlation between the targeted gene and protein expression and the echocardiographic data was also founded. Overall results pointed out that the serotonin pathway in lung and pulmonary artery tissues might have different roles in degenerative mitral disease with and without pulmonary hypertension.Pulmonary hypertension (PH) is defined as an increase in pulmonary vascular pressure. It is one of the most common complications that occur as a result of degenerative mitral valve disease (DMVD) in dogs. Serotonin (5-HT) can trigger the development of PH. Accordingly, this study investigated the changes in the expression of genes and proteins associated with local 5-HT signaling in the lungs and pulmonary arteries (PA) of dogs with PH secondary to DMVD. Lung and PA tissue samples were collected from the cadavers of fourteen small-breed dogs and divided into normal (n = 4), DMVD (n = 5) and DMVD with PH (n = 5) groups. Gene expression (tph1, slc6a4 and htr2a) was analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The expression of proteins (TPH-1, SERT, 5-HTR2A, ERK1/2 and pERK1/2) was examined by Western blot analysis and immunohistochemical staining. The results showed that the expression of genes and proteins evaluated by qRT-PCR and Western blot analysis in lung and PA tissues did not differ among groups. However, the expression of proteins related to 5-HT signaling tended to be upregulated in PA tissues from DMVD dogs with and without PH. Immunohistochemical examination revealed the overexpression of these proteins in the DMVD and DMVD with PH groups in lung tissue. These findings suggest a local effect of 5-HT signaling in DMVD dogs with and without PH.

Phenotypic and Transcriptional Changes of Pulmonary Immune Responses in Dogs Following Canine Distemper Virus Infection.

Canine distemper virus (CDV), a morbillivirus within the family Paramyxoviridae, is a highly contagious infectious agent causing a multisystemic, devastating disease in a broad range of host species, characterized by severe immunosuppression, encephalitis and pneumonia. The present study aimed at investigating pulmonary immune responses of CDV-infected dogs in situ using immunohistochemistry and whole transcriptome analyses by bulk RNA sequencing. Spatiotemporal analysis of phenotypic changes revealed pulmonary immune responses primarily driven by MHC-II+, Iba-1+ and CD204+ innate immune cells during acute and subacute infection phases, which paralleled pathologic lesion development and coincided with high viral loads in CDV-infected lungs. CD20+ B cell numbers initially declined, followed by lymphoid repopulation in the advanced disease phase. Transcriptome analysis demonstrated an increased expression of transcripts related to innate immunity, antiviral defense mechanisms, type I interferon responses and regulation of cell death in the lung of CDV-infected dogs. Molecular analyses also revealed disturbed cytokine responses with a pro-inflammatory M1 macrophage polarization and impaired mucociliary defense in CDV-infected lungs. The exploratory study provides detailed data on CDV-related pulmonary immune responses, expanding the list of immunologic parameters potentially leading to viral elimination and virus-induced pulmonary immunopathology in canine distemper.

Effect of sevoflurane post-conditioning on apoptosis and the expressions of Bcl-2 and Bax in lung tissue of cardiopulmonary bypass dogs

Purpose: To investigate the effects of sevoflurane post-conditioning on the expressions of Bcl-2 and Bax in lung tissues of cardiopulmonary bypass (CPB) dogs.&#x0D; Methods: Twelve healthy hybrid mongrels were divided into control (C) and sevoflurane postconditioning (S) groups. All dogs were subjected to thoracotomy in order to establish CPB. Ischemiareperfusion was conducted in the left lung of both groups. Thereafter, sevoflurane post-conditioning was given to group S. Femoral artery blood specimens were obtained prior to CPB (T1), as the left pulmonary artery was opened (T2), and 2 h after CPB (T3), for blood gas analysis. Respiration index (RI), oxygenation index (OI), and dynamic lung compliance (Cd) were calculated.&#x0D; Results: When T1 was compared with T2 and T3, their OI and Cd were significantly decreased in both groups, while RI showed the opposite trend (p &lt; 0.05). Values of OI and Cd at T3 in group S were increased significantly, relative to group C, while RI decreased (p &lt; 0.05). There were less lung tissue inflammation and structural disorder at T3 in Group S than in group C. Protein expressions and positive integral of Bcl-2 and Bax, and apoptosis at T2 and T3 in dog lung tissues of both groups were higher than those at T1 (p &lt; 0.05).&#x0D; Conclusion: Post-conditioning with sevoflurane is lung-protective in CPB dogs. The underlying mechanism may be based on the promotion of Bcl-2 expression and inhibition of Bax expression, thereby reducing apoptosis in dog lung tissue. Further investigations to determine its suitability for clinical applications in humans are, however, required.&#x0D; Keywords: Sevoflurane; Cardiopulmonary bypass; Bcl-2, Bax; Apoptosis; Pulmonary ischemiareperfusion injury

Quantitative Expression of Drug, Phospholipid and Nucleoside Transporters in the Lung Tissues across Species

ObjectiveIt has been proven that transporters play a pivotal role in organ distribution of drugs, and subsequently in drug efficacy and toxicity. Active transport processes may affect the local pulmonary disposition of drugs administered directly to the lung by the inhaled route as well as the uptake of drugs to the lung from the systemic circulation. While drug transporter expressions and their roles in drug disposition and elimination in the major elimination organs including intestine, liver and kidney are well‐characterized, the expression of drug transporters and the comparison across species in the lung remain overall poorly understood. For example, azithromycin levels in pulmonary tissue remained to be high for up to 5 days after a single oral dose, in contrast to much lower plasma levels. However, the mechanisms associated with azithromycin lung loading and efficacy remain unknown. The aim of this study was to comprehensively determine the mRNA and protein expression levels of drug transporters in the lung in human and preclinical species using quantitative targeted proteomics approaches. The findings can be useful to further explore potential mechanisms in lung specific disposition.MethodsTotal cellular mRNA was isolated from human lower lung tissues using a Qiagen mRNA isolation kit. qRT‐PCR was performed, and β‐actin mRNA expression was used to normalize target gene expression. The mRNA levels were expressed as a fold change using the 2‐ΔΔCt method. The total membrane proteins of lung tissues from human, monkey, dog and rat were extracted by Native Membrane Protein Extraction Kit, and subsequently digested by trypsin followed by the treatment of DTT and iodoacetamide (IAA). The levels of transporter proteins were quantified using a Sciex 7500 triple‐quadruple mass spectrometer coupled to a Shimadzu LC (SLC‐30A) system with optimized ionization conditions. The Na K‐ATPase level in the lung was measured as the membrane protein marker.Results and conclusionIn the current investigation, thirteen ABC efflux transporters and twenty‐three solute carriers (SLC) were characterized. Among those, mRNAs of eleven ABC transporters and fifteen SLC transporters were detected by the RT‐PCR method. In addition, eight ABC transporter and eleven SLC transporter proteins were quantified using the targeted proteomics LC‐MS/MS method. The mRNA expression pattern agrees with the protein expression; however, no quantitative correlation can be drawn between mRNA and protein expression. While OATP2B1 was only detected in human lung tissues, OATP2A1 and 3A1 are expressed in the lungs of human, monkey dog and rat. The expressions of three equilibrative nucleoside transporters (ENT1/2/3) in human lung tissues were higher than those in monkey. The expression of ABCA1, ABCA3 and ABCG1, the ABC transporters that are the regulators of cellular cholesterol and phospholipid homeostasis, were detected in all tested species, and found to be high in rat. Collectively, the comparison of transporter expression profiles can contribute to a better understanding of drug distribution and transport in the lung and aid pulmonary drug discovery and development.

Bronchoscopy and Lung Fine-Needle Aspiration for Antemortem Evaluation of Pulmonary Involvement in Dogs with Naturally Occurring Canine Leishmaniosis.

Clinical manifestations from the lower respiratory tract are rare in canine leishmaniosis (CanL), making bronchoscopy and lung fine-needle aspiration (FNA) seldomly justified. The aim of this prospective study was to investigate the involvement of Leishmania infantum in the lungs of dogs with naturally occurring CanL by bronchoscopy and examination of bronchoalveolar lavage fluid (BALF), bronchial mucosa biopsies, and FNA, using immunodiagnostics. Dogs with relevant concurrent diseases and azotemia were excluded. Cough was detected in 5/31 (16.1%) dogs. Lesions (hyperemia, edema, mucosal granularity, secretions) were identified upon bronchoscopy in 19/31 (61.3%) dogs. The cytology of BALF revealed histiocytic inflammation in 14/31 (45.2%) dogs; the parasite was identified in one dog (3.2%). The immunofluorescence antibody test in BALF was positive in 15/31 (48.4%) dogs. Histopathology of bronchial mucosa and/or adjacent alveoli revealed lesions (mononuclear cell infiltration, fibrosis, edema, thickening of the inter-alveolar septa) in 24/31 (77.4%) dogs, with no Leishmania amastigotes. Positive antigen staining was observed within the cytoplasm of mononuclear cells in immunocytochemistry and immunohistochemistry. Μononuclear cells showed antigenic positivity in bronchial mucosa (27/31; 87.1%), BALF (30/31; 96.8%), and lung FNA (27/31; 87.1%). In conclusion, lungs seem to be affected from CanL more commonly than previously believed, and bronchoscopy allows obtaining valuable samples for antemortem diagnosis.

Pulmonary capillary recruitment and distention in mammalian lungs: species similarities

Pulmonary arterial pressure rises minimally during exercise. The pulmonary microcirculation accommodates increasing blood flow via recruitment of pulmonary capillaries and, at higher flows, by distention of already perfused capillaries. The flow transition range between recruitment and distention has not been studied or compared across mammalian species, including humans. We hypothesised that the range would be similar. Functional pulmonary capillary surface area (FCSA) can be estimated using validated metabolic techniques. We reviewed data from previous studies in three mammalian species (perfused rabbit lungs and dog lung lobes, and exercising humans) and generated blood flow-FCSA curves over a range of flows. We noted where the curves diverged from the theoretical line of pure recruitment (Recruitment) and determined the flow where the curve slope equalled 50% that of Recruitment, or equalled that of a theoretical curve representing full capillary distention (Distention). The three mammalian species have similar flow ranges for the transition from predominantly recruitment to predominantly distention, with dogs having the highest transition point. Within the physiological range of most daily activity, the species are similar and accommodate increasing blood flow mainly via recruitment, with progressive distention at higher flows. This is highly relevant to pulmonary physiology during exercise.

Pathological study on the lungs of dogs in Chennai, Tamil Nadu

Pathological study on the lungs of dogs in Chennai, Tamil Nadu

Effectiveness and safety of robotic assisted-bronchoscopy system in locating and removing spring coils placed in the peripheral lung of beagle dogs: a pilot study

Objective: To evaluate the effectiveness and safety of the robotic assisted bronchoscope system for localizing and removing the spring coils that placed in the peripheral lung of beagle dogs. Methods: The study was conducted from June 18th to June 20th, 2021. Metallic lung coils were placed as the simulated lesions to the periphery of the lungs of two adult male beagle dogs using a bronchoscope under general anesthesia. The navigation path was planned by the navigation function that built in the robotic bronchoscope system. After training, the doctors operated the robotic bronchoscope system to locate and remove the coils from the lung. The navigation success rate, sampling success rate, position of the coil, navigation time, sampling time, and operation time were evaluated. The damage to the airway mucosa during the operation and the vital signs of the beagles during and post-operation were accessed. Chest computerized tomography (CT) was performed post-operation to detect if there were complications such as pneumothorax and bleeding. Results: A total of 12 spring coils were successfully inserted into the two beagles. All the navigation paths of the simulated lesions were successfully planned. The navigation success rate was 12/12. The navigation time was (43.9±19.8) seconds. The distance between the tip of the flexible endoscope arm and the target point measured by the navigation system was (6.93±2.15) mm. The locations of the simulated lesions were distributed in the 6th-8th generation of bronchi. The sampling success rate was 12/12. The sampling time was (42.4±11.3) seconds. There was no pneumothorax or mediastinal emphysema after the placement of the coil. The vital signs of the beagle dogs were stable throughout the operation, and no operation-related or postoperative complications occurred. Conclusions: The robotic bronchoscope system can be used to locate and remove the spring coils from the peripheral lung of beagle dogs, and the procedure is simple and safe. It suggests that the robotic bronchoscopy system has great clinical significance in the sampling and diagnosis of peripheral lung lesions.

Detecting pulmonary nodules by using ultrasound multiple scattering.

Although X-Ray Computed Tomography (CT) is widely used for detecting pulmonary nodules inside the parenchyma, it cannot be used during video-assisted surgical procedures. Real-time, non-ionizing, ultrasound-based techniques are an attractive alternative for nodule localization to ensure safe resection margins during surgery. Conventional ultrasound B-mode imaging of the lung is challenging due to multiple scattering. However, the multiple scattering contribution can be exploited to detect regions inside the lung containing no scatterers. Pulmonary nodules are homogeneous regions in contrast to the highly scattering parenchyma containing millions of air-filled alveoli. We developed a method relying on mapping the multiple scattering contribution inside the highly scattering lung to detect and localize pulmonary nodules. Impulse response matrices were acquired in ex-vivo pig and dog lungs using a linear array transducer to semi-locally investigate the backscattered field. Extracting the multiple-scattering contribution using singular-value decomposition and combining it with a depression detection algorithm allowed us to detect and localize regions with less multiple scattering, associated with the nodules. The feasibility of this method was demonstrated in five ex-vivo lungs containing a total of 20 artificial nodules. Ninety-five percent of the nodules were detected. Nodule depth and diameter significantly correlated with their ex-vivo CT-estimated counterparts (R = 0.960, 0.563, respectively).