Differences in aerodynamic characteristics of new and dysfunctional Provox®2 voice prostheses in vivo

Tracheoesophageal voice prostheses need to be replaced due to increased airflow resistance or retrograde leakage of fluid into the trachea as a consequence of biofilm formation. Previous in vitro studies show a change of aerodynamic features of biofilm covered voice prostheses after removal of the prostheses out of the patient. To assess these changes in an in situ situation, aerodynamic characteristics were measured within 45 patients at the beginning and at the end of the wearing process of the Provox 2 voice prosthesis. As a consequence, the influence of biofilm formation on aerodynamic characteristics can be evaluated. In the majority of cases, leakage through the prosthesis was the reason for replacement. No differences were found in the total flow, volume range and intratracheal pressure (ITP) of the voice prostheses measured. The airflow resistance of biofilm covered prostheses was significantly reduced compared to new clean prostheses. However, no correlation was found between the extent of biofilm and the different aerodynamic features measured. Biofilm formation on the Provox 2 is responsible for both reduction in airflow resistance and leakage through the prosthesis by deterioration of the silicone rubber material.     

COMPARATIVE STUDY OF AMINO ACID CONTENTS AND LDH ISOZYME BY ELECTROPHORESIS AND SLAB-PAGE IN ADULT WORMS OF ASCARIS LUMBRICOIDES, ASCARIS SUUM AND TOXOCARA CANIS^

Comparative studies are made on the relative percentages of amino acid content and LDH isozyme by electrophoresis and Slab-PAGE in adult worms of Ascaris lumbricoides, Ascaris suum and Toxocara canis. The results show that there are remarkable differences of Arg and His of 17 amino acids bet. ween Toxocara canis and human intestinal ascaris, human biliary ascaris and pig ascaris; there are also obvious differences of band positions of LDH isozyme electrophoretic patterns and band position and amount of slab-PAGE patterns among them, whereas no marked differences are found in these three indices in human intestinal ascaris, human biliary ascaris and pig ascaris.     

Bone disease in primary biliary cirrhosis: Lack of association with distal renal tubular acidosis

Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.