Localization of experimental ventricular myocardial lesions by the electrocardiogram

Electrocardiographic changes were studied in relation to the site of damage in thirty-four cats in which localized ventricular myocardial lesions had been produced by the electric cautery. Monophasic type curves were obtained which were classified as of the T₁ and T₃ types of Parkinson and Bedford. With almost complete consistency lesions in similar sites produced the same type of curve. Lesions on the anterior surface of the left ventricle produced curves of the T₁ type, while those on the posterior surface of the left ventricle, including the apex, yielded the T₃ type. All right ventricular sites, except the base anterior in which only a slight change was induced, gave curves of the T₃ type. At the apex posterior alone were the changes comparable in magnitude with those obtained in the left ventricle. Usually the changes produced were marked in two leads. In some the displacement of the R-T segment was oppositely directed in the remaining lead, while in others no significant deviation was observed in this lead. In a few instances an R-T elevation was present in all three leads but as a rule to a greater extent in one lead. In three experiments, in each of which the lesion was located at the base anterior, depression rather than elevation of the R-T segment occurred.     

Liver transplantation for argininosuccinic aciduria: clinical, biochemical, and metabolic outcome.

We report successful liver transplantation in a young adult with argininosuccinic aciduria but without cirrhosis. Plasma amino acid profile normalized and brain magnetic resonance spectroscopy indicated improved metabolism after transplantation. The general well-being of the patient and his quality of life improved. We suggest that orthotopic liver transplantation should be considered for patients with argininosuccinic aciduria even in the absence of cirrhosis, with the aim of correcting (at least in part) central nervous system metabolism, thereby preventing further neurological deterioration.     

Conus perimedullary arteriovenous fistula in a child: unusual angio-architectural features and pathophysiology

INTRODUCTION: The perimedullary arteriovenous fistulas are located on the pial surface and are usually supplied by spinal medullary arteries, that is, either by the anterior or posterior spinal arteries, with no intervening nidus between the feeder arteries and the venous drainage. The clinical findings are, more commonly, caused by progressive radiculomedullary ischemic processes secondary to steal vascular mechanism. As the vascular supply to the spinal cord and to the arteriovenous fistulas (AVF) is not shared with one another, the vascular steal phenomenon cannot be implicated in this case's physiopathology. Most probably, the mass effect caused by the giant venous dilatation was the pathophysiological mechanism involved in this lesion CASE REPORT: The authors describe the case of a 6-year-old girl with an intradural ventral arteriovenous fistula, with a giant venous dilatation, fed directly by L2 and L3 radiculomedullary arteries at the conus medullaris. There was no arterial supply to the fistula from the anterior or posterior spinal arteries. Selective spinal angiography showed an arteriovenous fistula supplied directly by two radiculomedullary arteries, with a large draining vein caudally. Interposing the arterial and venous vessels was a giant venous aneurysmal dilatation located ventral to the conus medullaris and extending from L3 to T6. The patient was successfully treated by a surgical approach through a laminotomy from L3 to T11. CONCLUSION: The type IV-C spinal arteriovenous malformations or perimedullary AVFs are rare lesions predominately described at the conus medullaris with various types of angio-architecture and controversial treatment.     

Posttransplantation B lymphoblastic leukemia with Burkitt-like features.

BACKGROUND: Posttransplantation Epstein-Barr virus-associated lymphoproliferative disease (PTLPD) occurs as a spectrum of disease ranging from benign, polyclonal, localized lymphoid hyperplasia to malignant, monoclonal, disseminated lymphoma, sometimes involving the bone marrow. To our knowledge, PTLPD has not been previously reported to present as acute lymphoblastic leukemia. METHODS: We report the case of a boy who developed PTLPD in the form of acute lymphoblastic leukemia 6 years after cardiac transplantation. He had greater than 90% bone marrow invasion by Epstein-Barr virus-positive B lymphoblasts with Burkitt-like features and a t(8;14) translocation. RESULTS: He was successfully treated with combination chemotherapy but unfortunately died, 6 months after completing treatment, from ischemic heart disease. CONCLUSIONS: B lymphoblastic leukemia may occur as a manifestation of PTLPD and should be included in the classification of these diseases. Bone marrow examination should be an essential part of the investigation of patients suspected of having PTLPD.     

A role for near infrared spectroscopy in the assessment of intermittent claudication.

BACKGROUND: Near infrared spectroscopy (NIRS) can be used to monitor muscle oxyhemoglobin (HbO2), deoxyhemoglobin (Hb) and cytochrome oxidase (CytOx) oxidation. We evaluated the changes in NIRS in patients with intermittent claudication (IC) pre- and postexercise. Microalbuminuria is an index of endothelial dysfunction. Therefore, we also assessed whether the urinary excretion of albumin increased postexercise in patients with IC. METHODS: Each participant (14 patients with IC and 10 controls) underwent a treadmill test; NIRS was continuously recorded. The urinary albumin:creatinine ratio (ACR) and ankle: brachial systolic pressure index (ABPI) were measured pre- and postexercise. RESULTS: The ABPI in the claudicants dropped significantly (p<0.001) postexercise. The pre-exercise ACR did not differ between claudicants and controls but postexercise, the ACR increased significantly (p<0.001) in the claudicants. There was a significant (p<0.001) difference in the degree of HbO2 deoxygenation between claudicants and controls; the rate of deoxygenation was significantly higher in claudicants than in controls (-8.4 vs. -3.4 mol/L.min, p=0.024). The period of recovery of HbO2 postexercise was also significantly slower in claudicants (192 vs 68 sec, p=0.003). There was a significant correlation between the increase in the ACR and time of recovery of HbO2 levels postexercise (r=0.86, p<0.001, n=24). A similar pattern was seen with CytOx. CONCLUSIONS: NIRS may provide a simple, non-invasive assessment of the severity of IC. Furthermore, because the ACR is a marker of endothelial damage, it is possible that NIRS changes also reflect endothelial integrity. These applications of NIRS technique should be assessed in a larger study.     

Retinoic acid and 1,25-dihydroxyvitamin D3 stimulate osteoclast formation by different mechanisms

The effects of retinoic acid (RA) and 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3 on osteoclast formation were examined in intact fetal long bones of different ages/developmental stages maintained in organ culture using a chemically defined medium with or without the presence of serum. Besides stimulating bone resorption, RA and 1,25-(OH)2D3 increased the number of osteoclasts in 19-day-old fetal rat tibiae. Likewise, these bone-resorbing agents induced and stimulated osteoclast formation in 19- and 18-day-old metatarsal bones which were osteoclast-free at the beginning of the culture. The response to 1,25-(OH)2D3 was greatly enhanced by 10% fetal bovine serum (FBS) irrespective of the developmental stage of the long bone. The response to RA was not. Light microscopic autoradiography after labeling of the cultures with tritiated thymidine showed that both RA and 1,25-(OH)2D3 induced osteoclast differentiation from proliferating and postmitotic precursors. However, neither agent was able to stimulate proliferation of osteoclast progenitor cells in the older bones (19 days). Studies on the formation of osteoclast-like (tartrate-resistant acid phosphatase positive) cells in bone marrow cultures indicated that FBS was a potent inducer of osteoclast-like cell formation. In the presence of FBS, 1,25-(OH)2D3 significantly stimulated this response, but RA did not. The results demonstrate that although both RA and 1,25-(OH)2D3 stimulate osteoclast formation from proliferating and postmitotic precursors in long bones in vitro, they do so by different mechanisms.     

Acquired haemophilia complicating the remission of a patient with high grade non‐Hodgkin's lymphoma treated by fludarabine

We report the development of a high titre antibody to factor VIII in a patient with previous high grade B cell non‐Hodgkin's lymphoma treated with fludarabine. Unlike previous reports of factor VIII inhibitors and lymphoproliferative disease this patient's lymphoma was in remission. We speculate that the occurrence of the inhibitor is another manifestation of the increasingly recognized autoimmune side‐effects of fludarabine.