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Biomedical subjects

B Pace

Publications and source records attributed to B Pace.

42 records · Page 3Linked to original sources
PubMed1970

Formation of all stable RNA species in Escherichia coli by posttranscriptional modification.

The kinetics of accumulation of the known stable RNA species (23S, 16S, and 5S rRNA and tRNA) in Escherichia coli C122 were monitored by polyacrylamide gel electrophoresis of purified cellular RNA, following termination of brief pulse labeling with (32)P-orthophosphate. Isotopically labeled stable RNA species appear only after a time lag, while total cellular RNA and the ostensible precursors to the stable RNA classes accumulate from the earliest times examined. It is concluded that all the known stable RNA species in E. coli are the products of posttranscriptional modification.

Electrophoresis, Disc↗
PubMedDate not supplied

Shoulder strength, power, and endurance in college tennis players.

Twenty-four college tennis players were tested for bilateral shoulder internal/external rotation strength on a Cybex 340 isokinetic dynamometer; they were positioned supine with the glenohumeral joint abducted to 90 degrees. Subjects produced significantly (P less than 0.01) more torque in internal rotation at 60 and 300 deg/sec in the dominant arm compared to the nondominant arm. Subjects also produced significantly more power in internal rotation at 60 deg/sec in the dominant arm. No significant differences between the dominant and nondominant arms were seen in internal rotation power at 300 deg/sec or in the internal rotation endurance ratio. No significant differences were seen in external rotation on any measurement. By significantly increasing the strength of the dominant shoulder in internal rotation without subsequent strengthening of the external rotators, muscle imbalances may be created in the dominant arm that could possibly affect the tennis player's predisposition to injuries caused by overloading of the shoulder joint. This study suggests that external rotation strengthening exercises should be implemented in tennis conditioning programs to maintain muscle strength balance, and possibly reduce the chance of overload injury.

Adult↗
PubMedDate not supplied

Pharmacologic induction of fetal hemoglobin synthesis: cellular and molecular mechanisms.

The switch from embryonic to fetal then to adult hemoglobin synthesis is a unique phenomenon during early human development. Fetal hemoglobin (Hb F) is known to interfere with polymerization of Hb S in erythrocytes. Several pharmacologic agents such as 5-azacytidine, myleran, hydroxyurea, erthropoietin, and butyrates enhance fetal hemoglobin production and have been used in hemoglobinopathy patients to ameliorate severe pain episodes and reduce severe anemia. Among these, hydroxyurea is the agent of choice because of its safety and ease of administration. One of the primary cellular mechanisms involved in pharmacologic induction of Hb F synthesis is rapid regeneration of erythroid precursors following the cytoreduction phase of certain pharmacologic agents. Molecular mechanisms involving changes in chromatin structure and/or transcription factor binding have been demonstrated for gamma gene induction by butyrate. Identifying the proteins involved in gamma gene activation by various compounds may offer a new strategy for gene therapy to cure hemoglobinopathy disorders.

Anemia, Sickle Cell↗