Validation of the estimation of corneal aberrations from videokeratography in keratoconus

PURPOSE: To validate the estimation of corneal aberrations from videokeratography against a laser ray tracing technique that measured total eye aberrations, in eyes without keratoconus (ie, cornea-dominated wave aberrations). METHODS: We measured total and corneal wave aberrations of three eyes diagnosed with keratoconus by slit-lamp microscopy and corneal topography: two eyes from one patient with early keratoconus and one eye with more advanced keratoconus. Total aberrations were measured with laser ray tracing. Corneal aberrations were obtained from corneal elevation data measured with a corneal videokeratoscope using custom software that performs virtual ray tracing on the measured front corneal surface. RESULTS: The keratoconus eyes showed a dramatic increase in aberrations (both corneal and total) particularly coma-like terms, which were 3.74 times higher on average than normal. Anterior corneal surface aberrations and total aberrations Were similar in keratoconus. This similarity was greater for the early keratoconus patient, suggesting a possible implication of the posterior corneal surface in advanced keratoconus. CONCLUSIONS: The similarity found between corneal and total aberration patterns in keratoconus provided a cross-validation of both types of measurements (corneal topography and aberrometry). Both techniques were useful in diagnosing and quantifying optical degradation imposed by keratoconus.     

Torsion of the greater omentum: treatment by laparoscopy

Four new cases of necrosis of the omentum secondary to torsion are reported. We review the associated signs and symptoms, which are usually those of an acute inflammatory condition in the right lower quadrant (RLQ), very similar to acute appendicitis. Because of acute abdominal pain in the RLQ, along with an uncertain diagnosis, laparoscopic surgery was performed in these cases. Laparoscopy demonstrated the existence of the omental infarction and allowed for complete treatment of the condition without the need for laparotomy.     

Aortoiliac thrombosis in antiphospholipid syndrome-case report and literature review

Antiphospholipid syndrome is accepted as one of the most important causes of hypercoagulable states. Thrombotic events in patients with antiphospholipid syndrome, predominantly women, occur at a younger age than in those suffering from atherosclerotic disease. The majority of the thrombotic events affect the deep venous system of the lower limbs and arterial thrombosis predominates in the cerebral territory. The use of anticoagulant therapy prevents recurrent thrombosis but the duration and intensity of treatment remain controversial. Aortic disease is an anecdotal fact in the literature. A case of infrarenal aortic occlusion involving both iliac arteries associated with primary antiphospholipid syndrome is presented.     

Intramedullary spinal cord metastases of melanoma

Intramedullary spinal cord metastases (ISCMs) are extremely rare. An exact diagnosis may be difficult even when the primary tumour is known. Patients usually present with back pain and signs and symptoms of spinal cord compression, such as hemiparesis or hemisensory impairments. Magnetic resonance imaging (MRI) is considered to be the main diagnostic tool for intramedullary lesions as it is very sensitive, but non-specific, in distinguishing between ISCMs and primary cord tumours. Optimal treatment in patients with ISCMs remains controversial. We report a case of ISCMs of melanoma, with a review of the clinical and radiological characteristics of these medullary lesions and their prognosis, as well as the different therapeutic approaches.     

Morbidity of lupus anticoagulants in children: a single institution experience

INTRODUCTION: The lupus anticoagulant (LA) and the anticardiolipin antibodies (ACA) are the antiphospholipid antibodies more relevant clinically. Their clinical manifestations are diverse with most patients being asymptomatic while others present venous or arterial thrombosis, and more rarely, bleeding. Our objectives were to evaluate clinical presentation of LA in children and to correlate it to LA behavior. PATIENTS AND METHODS: A retrospective cohort of patients (under 18 years old) who had a positive determination of LA followed by at least another determination of LA at a variable period was evaluated. Personal and family history, including infectious diseases temporally related to the event, were recorded. The screening of other coagulation disorders was performed according to symptoms, family history or laboratory results. RESULTS: Thirty-six patients were evaluated, median age was 10.8 years old, and 52.8% were female. Asymptomatic patients were 19.4% (7/36) of study population. Bleeding and thrombosis were found in 52.8% and 27.8%, respectively. Median LA determinations per patient were 3. von Willebrand disease was diagnosed in 66.7% of patients consulting for bleeding. A concomitant hemostatic defect was found in 8/10 patients with thrombosis (p = 0.003). LA behavior was not uniform and not correlated to symptoms. CONCLUSIONS: Most LA found in children is incidental and asymptomatic. In children with bleeding, LA might be a fortuitous finding associated with VWD. The persistence of LA does not imply a higher risk of thrombosis.     

Long-term treatment with insulin induces apoptosis in brown adipocytes: role of oxidative stress

Trying to define the precise role played by insulin regulating the survival of brown adipocytes, we have used rat fetal brown adipocytes maintained in primary culture. The effect of insulin on apoptosis and the mechanisms involved were assessed. Different from the known effects of insulin as a survival factor, we have found that long-term treatment (72 h) with insulin induces apoptosis in rat fetal brown adipocytes. This process is dependent on the phosphatidylinositol 3-kinase/mammalian target of rapamycin/p70 S6 kinase pathway. Short-term treatment with the conditioned medium from brown adipocytes treated with insulin for 72 h mimicked the apoptotic effect of insulin. During the process, caspase 8 activation, Bid cleavage, cytochrome c release, and activation of caspases 9 and 3 are sequentially produced. Treatment with the caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp (Z-VAD), prevents activation of this apoptotic cascade. The antioxidants, ascorbic acid and superoxide dismutase, also impair this process of apoptosis. Moreover, generation of reactive oxygen species (ROS), probably through reduced nicotinamide adenine dinucleotide phosphate oxidases, and a late decrease in reduced glutathione content are produced. According to this, antioxidants prevent caspase 8 activation and Bid cleavage, suggesting that ROS production is an important event mediating this process of apoptosis. However, the participation of uncoupling protein-1, -2, and -3 regulating ROS is unclear because their levels remain unchanged upon insulin treatment for 72 h. Our data suggest that the prolonged hyperinsulinemia might cause insulin resistance through the loss of brown adipose tissue.