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Biomedical subjects

N Ackerman

Publications and source records attributed to N Ackerman.

At least 19 recordsLinked to original sources

Surgical treatment of dorsal cortical fractures of the third metacarpal bone in thoroughbred racehorses: 53 cases (1985-1989).

Between January 1985 and May 1989, 53 Thoroughbred horses (mean age 3.2 years) were surgically treated for dorsal cortical fractures of the third metacarpal bone (MC III). All horses were treated with cortical drilling through the fracture line (osteostixis). Diagnosis of the fractures was confirmed by xeroradiography. Lifetime racing records were obtained for all horses. Forty-seven horses returned to racing after surgery (89%). The mean time between surgery and the first race was 6.8 months. Horses had a mean of 10.9 starts before surgery and 16.1 starts after surgery. The mean earnings per start before surgery was $6,459 and after surgery was $5,685. Of the 47 horses that raced after surgery, 70% raced at the same class or improved. Complications related to surgery were seen in 10 horses. Two horses had a second fracture of MC III at the same site, and were again treated by osteostixis, after which both horses returned to competition. Fractured drill bits were left in the MC III of 4 horses. One of these horses had catastrophic failure of MC III. Two horses developed subcutaneous infections and 2 horses had catastrophic failure of MC III in the surgically treated limb. Osteostixis appears to be an effective treatment for returning horses affected with dorsal cortical fractures to racing.

Animals

Evaluation and comparison of automated biopsy devices. Work in progress.

The performance of four automated biopsy devices (Bard Biopty, Bard Monopty, Microvasive ASAP 18, Medical Device Technologies Ultra-Cut) was compared when they were used to obtain 96 liver and 96 kidney samples from eight dogs under ultrasound guidance. There was no significant difference in the lengths of the samples obtained with the four devices. The Monopty device yielded a significantly greater mean weight of both kidney (30.8%) and liver (31.6%) samples compared with the other devices. There were no significant differences between the four devices relative to cellular and histologic preservation, crush artifact, and number of renal glomeruli or liver lobules and portal triads. Renal subcapsular hematomas were identified in most instances, and there was no difference between the devices in the amount of renal trauma resulting from their use. There was only one instance of severe injury to the liver. The choice of instrument should remain one of personal preference, since all four devices were satisfactory and none produced significantly greater renal or hepatic injury.

Animals

192iridium brachytherapy, using an intracavitary afterload device, for treatment of intranasal neoplasms in dogs.

After surgical removal of a primary intranasal neoplasm, an implant device, designed to deliver 192iridium (192Ir) brachytherapy, was positioned in the nasal cavity of 8 dogs. Ribbons containing 192Ir seeds were placed in the device, using an afterloading technique. Dosimetry, to a dose of 7,000 to 10,000 centiGray (cGy), was calculated to encompass the site previously occupied by the tumor and a 1-cm margin of surrounding normal tissue. The quantity of 192Ir implanted varied between 16.69 and 100.80 mg of radium equivalent. The duration of implantation ranged from 90 to 168 hours. All dogs tolerated the implant well, but had a mucoid nasal discharge after radiotherapy. The implant device allowed rapid application and removal of the radioactive ribbons. Mean (+/- SD) radiation exposure to each radiotherapist during seed loading and unloading was 14.4 (+/- 5.3) and 4.5 (+/- 0.9) mrem, respectively. A uniform dose distribution around the intranasal implant device was achieved; however, dogs that received doses in excess of 9,400 cGy at the dorsolateral surface of the nose and/or hard palate had bone and soft tissue necrosis between 70 and 120 days after treatment. One dog was euthanatized 50 days after treatment because of metastatic disease, and 2 dogs were euthanatized because of local tumor recurrence at 125 and 212 days. Death, considered unrelated to treatment, occurred in 1 dog that was euthanatized 27 days after treatment and in 3 dogs that died 30, 93, and 456 days after treatment. Necropsy was performed on 3 of these dogs and evidence of intranasal neoplasia was not observed. One dog remained disease-free at 587 days after treatment.

Adenocarcinoma

Unilateral congenital aneurysm of the jugular, linguofacial, and maxillary veins in a dog.

A 5-month-old female Gordon Setter was examined because of a soft, fluctuant, subcutaneous swelling in the right submandibular region. Clinical problems were not associated with the mass. Cytologic examination and blood gas analysis of an aspirate from the mass confirmed its contents to be venous blood. Venous angiography delineated a fusiform dilatation of the right jugular, maxillary, and linguofacial veins, with no evidence of obstruction or anomalous venous return to the heart. The dilated segments were surgically excised, and the tissue was submitted for histologic examination. The clinical, radiographic, and histologic features of this lesion supported the diagnosis of congenital venous aneurysm.

Aneurysm

In vivo inhibition of tumor growth of B16 melanoma by recombinant interleukin 1 beta. II. Mechanism of inhibition: the role of polymorphonuclear leukocytes.

Recombinant human interleukin 1 beta (IL 1 beta) inhibits growth of B16 melanoma in syngeneic C57BL/6 mice in a dose-dependent manner when given intratumorally, intradermally, or intramuscularly over a period of 5 to 7 days. Inhibition of tumor growth was rapid and measurable within 3 days after the initial injection and occurred regardless of the route of injection. However, only intratumoral (ITU) injections of IL 1 beta resulted in greater than 90% inhibition in tumor growth. This enhanced inhibition of tumor growth was not dependent on T or NK cells since inhibition of tumor growth occurred in nude and Beige mice. Also, a profound lymphopenia occurred in mice receiving IL 1 beta. Inhibition of tumor growth did correlate with an increase in the number of polymorphonuclear leukocytes (PMN's) in the circulation. However, only ITU injections of IL 1 beta increased the number of PMN's within the tumors. IM injections of IL 1 beta, while increasing the number of PMN's in the circulation, did not increase the influx of PMN's into the tumors. Furthermore, the transfer of PMN's directly into B16 tumors caused a 49% reduction in tumor growth without the presence of IL 1 beta. These results suggest that in vivo, PMN's may effectively control the growth of tumors and that IL 1 beta may increase this effectiveness by increasing the number of PMN's in the circulation and by locally stimulating the production of chemotactic factors for PMN's within the tumor.

Animals

Augmentation of the effect of doxorubicin with low-dose tumor necrosis factor in experimental liver metastasis.

The antitumor activity of recombinant human tumor necrosis factor was studied in vivo as a single agent and in combination with a conventional chemotherapeutic agent. Dosages of tumor necrosis factor of 100 micrograms, 50 micrograms, and 25 micrograms were injected intraportally in Sprague-Dawley rats containing hepatic implants of Walker carcinosarcoma. An effect on the tumor was seen but was associated with a significant acute mortality. Lower dosages of tumor necrosis factor, 10 micrograms, 5 micrograms, and 1 microgram, administered with 10 mg/kg of doxorubicin (Adriamycin) significantly enhanced the antitumor effect of doxorubicin without an acute mortality. This suggests that lower dosages of tumor necrosis factor with conventional chemotherapy may augment the latter's effect without any added toxicity.

Animals

Medical and surgical management of esophageal foreign body in a ferret.

A ferret was examined because of anorexia, repeated episodes of regurgitation, and subsequent dehydration. Radiography had revealed a radiodense midesophageal foreign body. Results of endoscopy of the esophagus, however, could not confirm the diagnosis. Contrast radiography revealed esophageal perforation, with subsequent penetration of the foreign body into the right pleural space, causing pleural effusion. Surgical repair of the esophagus was performed, and a gastrostomy feeding tube was inserted to provide adequate nutrition during esophageal healing. Nine days after surgery, radiography revealed a severe stricture at the esophageal surgical site. Surgery was repeated; the esophagus was transected, the stricture was removed, and esophageal tissues were closed in 2 layers. Systemically administered antibiotics and gastrostomy tube feedings were continued throughout the post-operative healing period. The esophagus healed with a mild stricture that diminished over time in response to corticosteroid administration.

Animals

Pulmonic stenosis and right-to-left atrial shunt in three dogs.

Using cardiac catheterization, pulmonic stenosis and right-to-left atrial shunt were diagnosed in 3 young dogs that were evaluated because of weakness, cyanosis, and polycythemia. Injection of contrast material into the caudal vena cava or crossing the atrial septal defect with the catheter tip from the right atrium into the left atrium confirmed the diagnosis. Tetralogy of Fallot, with right-to-left shunt through a ventricular septal defect, is a more common congenital malformation associated with the aforementioned clinical signs. Differentiation between the 2 defects is important, because surgical decompression of the right ventricle will lead to reduction of right atrial pressure and diminishment of the shunt.

Animals

Synthesis and antiinflammatory and analgesic activity of 5-aroyl-6-(methylthio)-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-ca rboxyl ic acids and 1-methyl-4-(methylthio)-5-aroylpyrrole-2-acetic acids.

5-Aroyl-6-(methylthio)-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-carb oxylic acids and 1-methyl-4-(methylthio)-5-aroylpyrrole-2-acetic acids were synthesized and assayed as antiinflammatory and analgesic agents. The majority of these compounds exhibit a surprisingly low level of antiinflammatory activity (rat carrageenan paw) but have considerable potency as analgesics (mouse phenylquinone writing). For example, the p-tolyl-substituted bicyclic and monocyclic compounds 44 and 58 are 301 and 66 times more potent than aspirin (mouse writhing) but only 3.4 and 1.5 times more potent than phenylbutazone in the antiinflammatory screen (rat paw).

Acetates

Echocardiographic evaluation of cardiac tamponade in dogs before and after pericardiocentesis: four cases (1984-1986).

The echocardiographic (M-mode and 2-dimensional) features (before and after pericardiocentesis) of 4 dogs with pericardial effusion and clinical evidence of cardiac tamponade were reviewed. M-Mode echocardiography revealed pericardial effusion, with exaggerated swinging motion of the heart and abnormal septal motion in all 4 dogs. In each case, 2-dimensional echocardiography demonstrated right ventricular diastolic free-wall collapse. Three dogs had right atrial diastolic collapse as well. Clinical signs improved, and right ventricular and right atrial diastolic collapse subsided after pericardiocentesis. Two-dimensional echocardiographic features of right atrial and ventricular collapse were used as indicators for determining the presence of cardiac tamponade.

Animals

Chronic urinary tract infection in dogs: induction by inoculation with bacteria via percutaneous nephropyelostomy.

Dogs were inoculated via percutaneous nephropyelostomy with bacteria isolated from canine patients with urinary tract infections (4 dogs were inoculated with Escherichia coli, 2 were inoculated with Proteus mirabilis, and 1 was inoculated with coagulase-positive staphylococci). At approximately monthly intervals after bacterial inoculation, bladder urine specimens were collected via antepubic cystocentesis, and renal pelvic urine specimens were collected via percutaneous nephropyelocentesis. Dogs were euthanatized between 89 and 294 days after bacterial inoculation. Extensive microscopic examination was conducted on the urinary tract of each dog. The dogs did not develop any of the common clinical signs of urinary tract infections (ie, increased frequency of urination, fever, craniodorsal abdominal [renal] pain, or malaise). Inflammation in the lower urinary tract of the dogs was more severe than that in the kidneys. Although pyelitis was present, extension into the outer medulla and renal cortex seemed to be confined to nephropyelostomy tracts. The most severe bladder lesion was found in the dog that developed cystic calculi after inoculation with coagulase-positive staphylococci.

Animals