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S L Brady

Publications and source records attributed to S L Brady.

5 recordsLinked to original sources

Simultaneous videofluoroscopic swallow study and modified Evans blue dye procedure: An evaluation of blue dye visualization in cases of known aspiration.

The reliability of the modified Evans blue dye (MEBD) test for the detection of aspirated materials in patients with tracheostomy has been questioned. The videofluoroscopic swallow study (VFSS) has been the standard procedure used to detect aspiration, but there are known risks and the VFSS is not always an available evaluation option for aspiration detection. The purpose of the present study was to investigate the visualization of blue tracheal secretions in cases of known aspiration as documented by the VFSS. Twenty consecutive simultaneous MEBD study and VFSS were completed on patients with tracheostomies at an acute rehabilitation hospital. Overall, the MEBD showed a 50% false-negative error rate. The MEBD identified aspiration in 100% of patients who aspirated more than trace amounts but failed to identify aspiration of trace amounts (0%).

Adolescent↗

Amplification of Pneumocystis carinii DNA on specimens scraped from slides.

A method for the detection of Pneumocystis carinii by polymerase chain reaction using specimens obtained by scraping bronchoalveolar lavage or tissue impression smears is described. The smears were scraped into water and then absorbed onto a glass-fiber filter. After fixing with methanol, the specimen on the filter was digested with proteinase K. The digestion mixture was then clarified, and a portion of the clarified supernatant was used as a template for the amplification of a portion of the mitochondrial rRNA gene of P. carinii. Using this method of sample preparation, we were able to amplify P. carinii DNA from both unstained and Giemsa stained smears.

Azure Stains↗

Discrimination of temporal jitter in patterned sequences of tones.

The perception of pure tone sequences in highly dependent on the serial pattern of tone frequencies. We propose that this phenomenon is mediated by a frequency-selective mechanism. Three models of the selective mechanism were evaluated in a temporal discrimination task. The observer was required to discriminate between two sequences of tone bursts. In one sequence the time interval between each tone burst was constant; in the other sequence the time interval was a random variable. A set of fixed and random pattern rules determined the frequency of each tone in the sequence. Discrimination performance was studied as a function of the magnitude of the time interval jitter and the serial pattern of tone frequency. Performance in the fixed pattern conditions was well described by a multiple-channel model in which timing information is available between tones within the same frequency region. The influence of higher order attentional factors was randomly determined. The frequency-selective mechanism appears to be sensitive to uncertainty about the frequency pattern of the input. Repeating the random pattern within each trial effectively eliminated this uncertainty. This result is consistent with experiments on the discrimination of word-length auditory patterns and temporal cues in speech.

Attention↗

Characterization of the gene encoding a histidine and aspartic acid-rich protein from Pneumocystis carinii.

A cDNA clone derived from Pneumocystis carinii contained an unusual sequence (GTGATG)2(ATGGTG)4(ATG)4 and many GAT repeats. It was found to encode a histidine and aspartic acid-rich protein (HARP). The complete cDNA contained an 888-bp open reading frame encoding a putative protein of 32.6 kDa. The deduced HARP protein contained 39 aspartic acid and 22 histidine residues. The genomic copy of the HARP gene (1203 bp in length) was found to contain 3 small introns of 46, 44, and 38 bp, respectively. HARP was predicted by computer programs to be a plasma membrane protein with nickel-binding activity.

Amino Acid Motifs↗