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David Dahan

Publications and source records attributed to David Dahan.

6 recordsLinked to original sources
PubMed2006

Lupus-associated pancreatitis.

A number of lupus patients develop episodes of acute "idiopathic" pancreatitis, unrelated to the known causes of mechanical obstruction of the pancreatic duct or toxic-metabolic etiologies. This lupus-associated pancreatitis is rare. The estimated annual incidence was 0.4-1.1/1000 lupus patients. A literature search found detailed descriptions of this condition in 77 lupus patients. Their median age was 27, and 88% were females. Abdominal pain was the most frequent pancreatitis-related symptom (88%). In 97% the diagnosis of pancreatitis was based on laboratory evidence of elevated serum amylase or lipase. Most cases were unrelated to treatment with steroids or azathioprine. Most of the patients (84%) had active lupus at the time of pancreatitis. Mortality rate was 27%, higher than in non-SLE associated pancreatitis. Active lupus and several biochemical abnormalities, but not treatment with steroids or azathioprine, were significantly associated with increased mortality. Treatment with steroids lowered the mortality by 67% compared to non-treated patients.

Humans↗
PubMed2006

Lupus-associated pancreatitis.

OBJECTIVES: Involvement of the pancreas in systemic lupus erythematosus is rare. The purpose of this article is to provide a detailed review of lupus-associated pancreatitis. METHODS: We describe 3 patients with lupus-associated pancreatitis and review the English literature of the last 30 years, including the demographic, clinical, therapeutic, and prognostic aspects of this disorder. RESULTS: There were detailed descriptions of 77 patients, 88% were females. Median age was 27 years. In 44% of the patients pancreatitis developed within 1 year of the diagnosis of lupus, and 84% had active lupus at the time of pancreatitis. Abdominal pain was the most frequent pancreatitis-related symptom (88%), followed by nausea or vomiting (67%). In 97% the diagnosis of pancreatitis was based on laboratory evidence of elevated serum amylase or lipase. Abdominal computerized tomography and ultrasonography did not show signs of pancreatic involvement in 24 and 45%, respectively. The mortality rate was 27%; active lupus and some biochemical abnormalities were significantly associated with increased mortality. Treatment with corticosteroids or azathioprine was not associated with increased mortality. On the contrary, mortality was decreased in patients who were treated with these agents after the onset of pancreatitis (20% mortality, compared with 61% among those who were not treated with steroids for their pancreatitis, P = 0.005). CONCLUSIONS: Pancreatitis should be suspected in any SLE patient with abdominal pain. Mortality rate is related to both active lupus and some biochemical markers. In most cases, the onset of pancreatitis appears unrelated to previous treatment with steroids or azathioprine. Moreover, treatment with these medications improves prognosis.

Abdominal Pain↗
PubMed2005

Self-starting ultralow-jitter pulse source based on coupled optoelectronic oscillators with an intracavity fiber parametric amplifier.

A self-starting optical pulse source based on mutually coupled optoelectronic oscillators is described. The system employs a phototransistor-based microwave oscillator that is coupled to a fiber cavity optoelectronic oscillator with an intracavity fiber parametric amplifier. It self-starts and exhibits 3 ps pulses at a rate of 10 GHz with extremely low jitter of 30, 29, and 40 fs (for integration bandwidths of 100 Hz-15 kHz, 500 Hz-1 MHz, and 100 Hz-1 MHz, respectively).

Journal Article↗
PubMed2003

Noise-reduction capabilities of a raman-mediated wavelength converter.

We describe ultrawideband Raman-mediated wavelength conversion. The nonlinear conversion transfer function is calculated analytically and simulated numerically in the cw regime, and the predicted performance is confirmed experimentally. Data conversion from long- to short-wavelength bands with signal reshaping and significant noise reduction are demonstrated experimentally at 10 Gbits/s and modeled by numerical simulations. Q factors and extinction ratios that are both larger than 10 dB are possible over an effective conversion bandwidth of 35 nm.

Journal Article↗