Evaluation of thoracic duct healing after experimental laceration and transection

Healing of the thoracic duct (TD) was evaluated clinically and histologically in six healthy dogs. A 2.5 cm longitudinal laceration of the caudal TD was created in three dogs and the caudal TD was completely transected in three other dogs. The site of the defect was identified by placing one 4-0 stainless steel suture in the tissue adjacent to the TD defect. All dogs developed a chylous effusion confirmed by biochemical analysis. By five days after surgery in dogs with TD lacerations, and by 10 days after surgery in dogs with TD transections, thoracic effusion had ceased. Lymphangiography, performed seven days after resolution of thoracic effusion, showed TD patency only in the dogs with TD lacerations. The TD did not appear to be patent in dogs with TD transections. Histologically, in dogs with TD lacerations, one moderately dilated lymphatic vessel was seen at the surgical site in one animal and the thoracic duct and other lymphatics in the two other dogs appeared normal. Minimal perivascular accumulations of neutrophils, macrophages, and lymphocytes were present adjacent to two lymphatics in one animal. A mild increase in fibrous connective tissue and neovascularization was present in the adjacent subpleura. In dogs with complete transections, three to six dilated lymphatics were present at the transection site. Mild thickening of the tunica media was present in one thoracic duct, associated with a "J"-shaped area of condensed collagen, presumed to be a collapsed thoracic duct in one animal. Mild to moderate accumulations of macrophages, lymphocytes, and moderate neovascularization was present in the surrounding tissue, separating it from the underlying connective tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Severe bilateral fibrosing pleuritis associated with chronic chylothorax in five cats and two dogs

Severe bilateral fibrosing pleuritis was diagnosed in 5 cats and 2 dogs with chronic chylothorax. All animals were dyspneic on initial examination and remained moderately to severely dyspneic after thoracentesis. Radiographic evidence of fibrosing pleuritis included rounded lung lobes and failure of the lungs to reexpand following effective pleural drainage. Fibrosing pleuritis was also suggested in several animals with radiographic evidence of pleural fluid, in which pleural fluid could not be retrieved. Macroscopically, the lung lobes of all animals were compressed and atelectatic to various degrees, and the pleura appeared to be diffusely thickened and roughened. In several animals, fibrous adhesions were found between the parietal and visceral pleura of some lobes. Lung lobes were markedly constricted and appeared as small, smooth, rounded hilar masses in 4 animals. Mild to moderate pulmonary edema was evident in 3 animals at necropsy. Six of the 7 animals died (2) or were euthanatized (4) within 72 hours after the diagnosis of fibrosing pleuritis. The fibrosing pleuritis developed in 1 animal with lymphoblastic lymphosarcoma and chylothorax after treatment via passive pleuroperitoneal drainage; this animal was euthanatized because of underlying neoplasia. One cat, in which decortication was performed and resulted in marked reexpansion of the lung lobes, died 4 hours after surgery with signs compatible with pulmonary edema. On the basis of our findings, we suggest that animals with chronic chylothorax are at risk to develop fibrosing pleuritis. Furthermore, animals with severe bilateral fibrosing pleuritis should be given extremely guarded prognoses.

Lymphoscintigraphy in healthy dogs and dogs with experimentally created thoracic duct abnormalities

Lymphoscintigraphic evaluation of the thoracic duct (TD) was performed in 10 healthy and 12 dogs with experimentally created TD abnormalities (6 dogs with TD lacerations and 6 dogs with cranial vena ligations). Complete imaging took 4 hours and caused no adverse effects or complications. Lymphoscintigraphy of healthy dogs failed to image the TD; however, background activity in the abdomen and thorax, and radioactivity in the kidneys, bladder, liver, and heart were noticed. Lacerations and transections of the TD were experimentally created in 6 dogs to ascertain whether TD rupture could be detected with lymphoscintigraphy. Lymphoscintigraphy was performed within 48 hours of creating the TD defect. There was no significant difference in the scintigraphic pattern of healthy dogs and those with experimentally created TD defects. Ligation of the cranial vena cava was performed in 6 dogs; 3 dogs developed chylothorax. In those 3 dogs, diffuse radioactivity was imaged in the thorax and was compatible with thoracic lymphangiectasia. In one of these dogs, linear activity consistent with the TD and localized regions of radioactivity cranial to the heart (compatible with the mediastinal lymph nodes) were noticed. Lymphoscintigraphic findings in these dogs correlated with lymphangiographic findings.

Neurologic manifestations of trypanosomiasis in a dog

A 13-month-old Doberman Pinscher was evaluated because of slowly progressive paraparesis and signs of depression. The dog had temporal, supraspinatus, and infraspinatus muscle atrophy, bilateral enophthalmos, superficial inguinal lymphadenopathy, tachycardia with pulse deficits, and lesions of active and inactive chorioretinitis. Neurologic abnormalities included hyperreflexic patellar reflexes, lack of conscious proprioception, signs of superficial pain in the hind limbs, and depressed hopping reflexes in the forelimbs. Cranial nerve abnormalities included decreased sensation in the left nostril and a delayed gag reflex. Results of cerebrospinal fluid analysis were characteristic of nonsuppurative inflammation. A diagnosis of multifocal neurologic disease was made. The dog did not have serum titers for fungal diseases, canine distemper, Ehrlichia canis infection, borreliosis, Rocky Mountain spotted fever, or toxoplasmosis. The dog did not respond to various antimicrobial treatments, and only slightly responded to corticosteroid treatment. The dog died during an anesthetic procedure. The postmortem diagnosis of Trypanosoma cruzi infection (canine Chagas disease) was made on identification of the amastigote form of the organism in sections of brain, spinal cord, and myocardium.

Generalized lymphangiectasis in a dog with subcutaneous chyle and lymphangioma

A 2 1/2-year-old spayed Great Dane was evaluated for large, fluctuant, chyle-containing swellings on the ventral portion of the left side of the abdomen. Multiple abnormalities of the lymphatic system were diagnosed, including thoracic duct obstruction, lymphangioma, subcutaneous chyle reflux, intestinal lymphangiectasia, and dilatation of hepatic, mesenteric, and pleural lymphatic vessels. Mesenteric lymphangiography revealed leakage of contrast medium into the subcutaneous tissues adjacent and to the left of the second lumbar vertebral body. Dietary and surgical management to control the chylous reflux were unsuccessful, and the dog died approximately one year after the skin lesions were first observed.

Enzymic conversion of reticuline to salutaridine by cell-free systems from Papaver somniferum

A cell-free extract from the opium poppy, Papaver somniferum, was prepared that utilized hydrogen peroxide to convert (+/-)-[3-3H]reticuline to [3H]salutaridine in 80-85% yield based on consumed [3-3H]reticuline. The phenolic-coupling enzyme activity was not detected in the crude homogenate of whole plants. Reticuline conversion to salutaridine was accomplished only after methods were developed to separate both alkaloid and hydrogen peroxide degrading activities from the desired enzyme activity by centrifugal fractionation of carefully prepared stem and root extracts. Purity of the enzymatically produced [3H]salutaridine was established by chromatographic methods and synthetic conversion to [3H]-thebaine.