28 research outputs found

    An assessment of differences in lower stratospheric temperature records from (A)MSU, radiosondes, and GPS radio occultation

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    Uncertainties for upper-air trend patterns are still substantial. Observations from the radio occultation (RO) technique offer new opportunities to assess the existing observational records there. Long-term time series are available from radiosondes and from the (Advanced) Microwave Sounding Unit (A)MSU. None of them were originally intended to deliver data for climate applications. Demanding intercalibration and homogenization procedures are required to account for changes in instrumentation and observation techniques. In this comparative study three (A)MSU anomaly time series and two homogenized radiosonde records are compared to RO data from the CHAMP, SAC-C, GRACE-A and F3C missions for September 2001 to December 2010. Differences of monthly anomalies are examined to assess the differences in the datasets due to structural uncertainties. The difference of anomalies of the (A)MSU datasets relative to RO shows a statistically significant trend within about (−0.2±0.1) K/10 yr (95% confidence interval) at all latitudes. This signals a systematic deviation of the two datasets over time. The radiosonde network has known deficiencies in its global coverage, with sparse representation of most of the southern hemisphere, the tropics and the oceans. In this study the error that results from sparse sampling is estimated and accounted for by subtracting it from radiosonde and RO datasets. Surprisingly the sampling error correction is also important in the Northern Hemisphere (NH), where the radiosonde network is dense over the continents but does not capture large atmospheric variations in NH winter. Considering the sampling error, the consistency of radiosonde and RO anomalies is improving substantially; the trend in the anomaly differences is generally very small. Regarding (A)MSU, its poor vertical resolution poses another problem by missing important features of the vertical atmospheric structure. This points to the advantage of homogeneously distributed measurements with high vertical resolution

    Severe dysphagia in lower cranial nerve involvement as the initial symptom of Wegener's granulomatosis.

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    We observed a 42-year-old woman presenting with severe dysphagia secondary to paralysis of the lower cranial nerves and right phrenic nerve involvement, followed by respiratory failure. An EMG confirmed bilateral denervation of the 9th, 10th, 11th and 12th cranial nerves and right phrenic nerve. Videolaryngoscopy showed bilateral vocal fold immobility. Anemia, elevated ESR, microhematuria and C-ANCA (PR-3) antibodies were detected. Brain MRI and CSF were normal. A chest CT showed bilateral, irregular pulmonary lesions. An 18F-FDG total body scan showed diffuse hypermetabolic regions in both pulmonary bases, in the mediastinic region and in the rhinopharynx, raising the suspicion of a neoplastic process. A transthoracic biopsy disclosed nodular granulomatous aggregates with multinucleated giant cells, supporting the diagnosis of Wegener's granulomatosis. Immunosuppressive therapy achieved complete clinical resolution and cleared the pulmonary lesions. To the best of our knowledge this is the first report of Wegener's granulomatosis presenting with neurogenic dysphagia due to lower cranial nerve pals

    X-linked adrenoleukodystrophy with olivopontocerebellar atrophy.

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    6X-linked adrenoleukodystrophy (X-ALD) is a rare neurological disorder characterized by adrenal, gonadal and nervous system dysfunction. Patients usually develop spinal cord degeneration with involvement of the cerebral white matter. While a spinocerebellar variant has been described, the selective involvement of cerebellar white matter is very rare. We report the case of a patient affected by X-ALD whose clinical and magnetic resonance imaging (MRI) results resembled olivopontocerebellar atrophy. He was a 29-year-old mentally retarded man, who began to complain of slowly progressive gait ataxia after an 8-year history of Addison's disease. Serial MRI revealed marked cerebellar atrophy involving the inferior cerebellar vermis and brainstem, but sparing the supratentorial white matter. The diagnosis of X-ALD was confirmed by elevated levels of very long-chain fatty acids in the serum. After 2 years follow-up, the patient developed spastic paraparesis. The patient represents an unusual clinical presentation of X-ALD, as further confirmed by the MRI results. Consequently, cerebellar symptoms should be considered as a clinical presentation of X-ALD. Early recognition of this rare disorder would be useful for genetic counselling and therapy.nonenoneVianello M; Manara R; Betterle C; Tavolato B; Mariniello B; Giometto BVianello, M; Manara, R; Betterle, C; Tavolato, B; Mariniello, B; Giometto,
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