Evaluation of improved transvenous heartworm extraction brush in dogs with caval syndrome

Background@#Heartworm infection in dogs is caused by Dirofilaria immitis and common in shelter animals and outdoors dogs. Caval syndrome can develop with severe infection and physical heartworm removal is essential with heartworm burdens. In this study, we used an improved transvenous heartworm extraction brush, which was expected to cause less cardiovascular damage and allow easier manipulation. @*Objectives@#This study aims to evaluate efficacy of this improved transvenous heartworm extraction brush. @*Methods@#The brush was designed to improve upon the limitations of the previous brushtype devices. The brush was made of a polyvinyl chloride tube and threads of polyamides or polyglyconates. Metal material was inserted at the front tip for easy visualization under fluoroscopy. The eight dogs diagnosed with caval syndrome with large numbers of heartworms and pulmonary hypertension were used in this study. The removal procedure began with the dissection of the subcutaneous tissue around the right jugular vein. The device was inserted through the jugular vein. After insertion, the tube was rotated to catch the heartworms and extracted with the heartworms hanging on the threads. The procedure was repeated several times. Lastly, jugular vein and skin sutures were made. Adulticidal therapy was administered after heartworm removal. @*Results@#The mean number of removed heartworms was 10.5 ± 4.24 and mean number of remaining heartworms was 0.63 ± 1.06. Total procedure time was 72.63 ± 51.36. Except for three cases, heartworms were not detected on ultrasonography after the procedure. No procedure-related side effects were observed within the 1- to 2-mon. @*Conclusions@#An improved transvenous heartworm extraction brush is efficient for heartworm removal in dogs with caval syndrome.

Candida albicans urinary tract infection in a Shih Tzu dog with immune-mediated hemolytic anemia

An 8-year-old castrated male Shih Tzu dog (weighing 7.0 kg) presented with anemia and lethargy. Initial diagnosis indicated immune-mediated hemolytic anemia. During therapy, a secondary urinary infection, probably due to the immune suppressive therapy, was diagnosed. Subsequent diagnostic tests, including urinalysis and urine culture, indicated candidal cystitis. Despite ketoconazole therapy for candidal cystitis, the dog died suddenly. A Candida albicans infection was confirmed upon postmortem evaluation. Prolonged immunosuppressive therapy might be the cause of this infection. This is the first case report describing a Candida albicans urinary tract infection accompanied by hemolytic anemia in a dog in Korea.

The comparison of torque values in two types of miniscrews placed in rabbits: tapered and cylindrical shapes: Preliminary study / 대한치과교정학회지

OBJECTIVE: This study compared the stability of cylindrical miniscrews (Cy, 7 mm in length) with that of tapered miniscrews (Ta, 5 mm in length), using torque values to determine if the healing time before loading affects the stability of the miniscrew and if the insertion torque is associated with the removal torque measured after a few weeks of healing. METHODS: Ta and Cy with different thread lengths were placed in the tibias of 12 female New Zealand white rabbits (body weight: 3.0 - 3.5 kg), and the maximum insertion torque values (ITV) were measured. No orthodontic forces were applied so as to allow us to determine the pure effects of the different shapes. After 3 different healing periods (2, 4, and 6 weeks), maximum removal torque values (RTV) were measured immediately before the rabbits were sacrificed. RESULTS: No miniscrews were loosened. There were no significant differences in ITV or RTV between the Ta and Cy nor were there any significant differences in the ITV and RTV between the 3 groups, which had different healing periods. There was a correlation between the ITV and RTV. CONCLUSIONS: Shorter Ta showed similar stability as Cy, as determined by torque values. This result strongly suggests that the tapered shape is more advantageous than the cylindrical shape. The RTV did not increase significantly over time. It is recommended that a miniscrew be loaded immediately; waiting a few weeks before loading should be avoided. The correlation between the ITV and RTV suggests that the ITV can be used to estimate a screw's future stability.

Angiogenesis Induced by the Implantation of Autogenous Whole Bone Marrow Stem Cells in an Ischemic Animal Model

PURPOSE: Bone marrow contains many kinds of primitive cells and endothelial progenitor cells that secrete several growth factors. We hypothesized that angiogenesis could be induced by autogenous whole bone marrow stem cell implantation in an animal ischemic limb. METHOD: A chronic ischemic hind limb model was created by encircling the femoral artery with an ameroid constrictor (2 mm inner diameter) in a dog model. About 20 ml of autogenous whole bone marrow stem cells were aspirated from the femur and then injected into ischemic limb muscles. Contralateral limbs injected with 20 ml of normal saline as controls. To assess angiogenic effects, an angiogram and a histologic evaluation were performed at 8 weeks after bone marrow stem cell implantation. RESULT: Imaging analysis of angiograms showed that newly developed capillaries were significantly more plentiful in treated limbs. Mean capillary density in the treated limb group was significantly greater than that in the control group (151+/-11.7 vs 81.5+/-7.2 cap/mm2, respectively, P<0.05), and the proportion of larger diameter (Fig. 6) newly developed capillaries was significantly higher in treated limbs than in control limbs. CONCLUSION: These findings indicated that autogenous whole bone marrow stem cell implantation increases the efficiency of angiogenesis.

Tissue Engineering of Vascular Graft Using Autogenous Bone Marrow Cell and Allogenous Acellular Vessel

PURPOSE: The objective of this study is to develop a tissue-engineered vascular graft using autologous bone marrow-derived cells (BMCs) and allogenous acellular vascular graft. METHOD: We developed a tissue- engineered vascular patch using autologous BMCs and allogenous acellularized tissue patches. The patches were implanted into the inferior vena cava of a canine in vivo model. Three weeks after implantation, the retrieved patches were investigated by histological and immunohistochemical analyses. RESULT: Cultured BMCs differentiated into endothelium-like and smooth muscle-like cells. The patch graft maintained patent for 3 weeks without any signs of thrombus formation. Histological, immunohistochemical, and scanning electron microscopic analyses of the retrieved patches revealed that new vascular tissues were successfully reconstructed within the patch matrices. CONCLUSION: The tissue-engineered vascular patch using autogenous BMCs and allogenous acellularized matrix maintained patent for 3 weeks and showed vascular tissues generation similar to native blood vessel. The findings of no thrombus and no aneurysmal formation in patch indicated good antithrombogenic property and mechanical property. This study demonstrates the feasibility of utilizing BMCs as an alternative cell source to reconstruct vascular tissues.

Development of a Tissue-Engineered Vascular Graft Using Autologous Bone Marrow-Derived Cells and Biodegradable Polymer Scaffold

PURPOSE: The objective of this study is to develop a tissue-engineered vascular graft using autologous bone marrow-derived cells (BMCs) and biodegradable polymer scaffold. METHOD: Autologous canine BMCs were isolated from bone marrow aspirate and cultured. A tubular scaffold was fabricated by immersing polyglycolic acid (PGA) sheet in poly (glycolide-co-caprolactone) (PGCL) solution and wrapping it around a cylindrical mold. The expanded BMCs were seeded onto the PGA/PGCL tubular scaffold (internal diameter: 7 mm, length: 35 mm) and further cultured in vitro for 1 week. The graft was anastomosed to the abdominal artery in a canine model. One week after implantation, the retrieved graft was investigated by histological and immunohistochemical analyses. RESULT: Cultured BMCs differentiated into endothelial-like and smooth muscle-like cells. The PGA tubular scaffold reinforced with PGCL was successfully implanted in an animal model without graft rupture. The vascular graft engineered with BMCs was occluded at 1 week after implantation due to thrombus formation. Histological and immunohistochemical analyses of the retrieved graft revealed that extracellular matrix proteins such as smooth muscle alpha-actin, smooth muscle myosin heavy chain and collagen were produced partially in the graft media. CoNCLUSION: The tissue-engineered vascular graft developed in this study led to graft failure due to early occlusion. Nevertheless, it is confirmed that the PGA/PGCL scaffold has microstructures appropriate for cell proliferation and good mechanical properties. This result suggests the possibile application of this scaffold as a material for engineering of diseased vascular tissues.

A Case of Severe Bradyarrhythmia after Ingestion of Rhododendron Brachycarpum

Rhododendron brachycarpum has been known as a panacea in Korean folk medicine, and is used to treat various diseases including hypertension. Excessive ingestion can cause intoxication by grayanotoxin. We experienced a 59 year-old man suffering of grayanotoxin intoxication following excessive ingestion of Rhododendron brachycarpum. The patient presented dizziness, weakness, and chest discomfort with cold sweats. Electrocardiography showed marked sinus bradycardia with atrio-ventricular dissociation. With intravenous saline and atropine, the patient recovered. This case calls attention to the potential cardiotoxicity of Korean folk medicine Rhododendron brachycarpum.

Atrial Septal Aneurysm / 대한흉부외과학회지

A life-long anticoagulation for the prevention of ischemic cerebral events by thromboemboli has been conventionally introduced for the treatment of an atrial septal aneurysm. However, due to the recent decrease of the risks in the open heart surgery, the alternative therapeutic modality has been introduced for the prevention of complications of the anticoagulation. A 41-year old female with dizziness was admitted to our hospital. She was diagnosed a shaving atrial fibrillation and a cerebellar infarction, and an atrial septal aneurysm was detected by transesophagel echocardiography that was not detected by the transthoracic echocardiography. Surgery was approached to the right submammarial anterolateral thoracotomy. The atrial septal aneurysm was obliterated by a purse-string suture and plication. Surgial results were excellent with normal sinus rhythms and esthetically satisfying appearance.

Pulmonary Lymphangioleiomyomatosis with Pneumothorax / 대한흉부외과학회지

Lymphangioleiomyomatosis(LAM) is defined as an abnormal proliferation of smooth muscles in the lung tissue throughout lymphatics, vascular and bronchial structure. A 52-year-old postmenopausal woman was admitted to our hospital for recurrent pneumothorax. She was treated for medroxyprogesterone by LAM 1 month ago. We performed operation of pulmonary partial resection and pleurodesis. The patient is receiving continuous medroxyprogesterone and Leuplin administration, and currently, 6 months after the operation, is still showing good results.

Cricopharyngeal Achalasia: A Case Report / 대한흉부외과학회지

Idiopathic cricopharyngeal achalasia is a rare condition that produces oropharyngeal dysphagia. It is caused by spasm of the cricopharyngeus and inability to relax with swallowing. A prominent muscle bar at the upper esophageal sphincter is a typical finding of the esophagogram. Cricopharyngeal myotomy is the treatment of choice. We report a case of cricopharyngeal myotomy for 61-year-old female patient.

Comparison of Continuous Mechanical Ventilation and Internal Fixation in Flail Chest Injuries / 대한흉부외과학회지

From January, 1992 to June, 1996, )7 patients with flail chest were treated at Sonnchunhyang university hospital. 15 patients were managed by internal fixation of fractured ribs, whereas the remaining 22 patients were managed by endotracheal intubation and intermittent positive-pressure ventilation alone. There were no difference between two groups in age, sex, the severity of injury to the chest wall and the nature of associated injuries. Average dur'Btion of assisted ventilation was 5.7 +/-1.7 days in the patients treated by internal fixation versus 8.7 +/-3.3 days In the patients treated by continuous me hanical ventilation. Average stay in the intensive care unit was 8.3 +/-3.9 days for the patients treated by internal fixation, whereas it was 13.2+/-4.1 days in the group treated by continuous mechanical ventilation alone. In the group treated by internal fixation, complications were 3 atelectases(20.0%), 1 pneumonia(6.7%), 2 operative wound problems(12.3%) and 1 barotrauma(6.7%). In the other group, 7 atelectases(31.8%), 4 pneumonitis(18.2%), 2 empyemas(9.1%) and 3 barotraumas(1).6%). The mortality rate was 13.3%(2/15) in the surgically treated patients, whereas it was 22.7%(5122) in the other group. The treatment of flail chest by internal fixation resulted in speedy recovery, decreased complications and mortalities, and better ultimatc cosmetic and functional results.