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B J Ross

Publications and source records attributed to B J Ross.

5 recordsLinked to original sources
PubMed1999

Expression of the voltage-gated chloride channel ClC-2 in rod bipolar cells of the rat retina.

Voltage-gated chloride channels (ClC) are highly conserved during evolution and appear to participate in a variety of physiological functions. Recently, ClC-2 was proposed to play a role in stabilizing the chloride equilibrium potential near or below the resting membrane potential in neurons expressing ligand-gated chloride channels. Because rod bipolar cells in mammalian retina express three forms of inhibitory ligand-gated chloride channels, we decided to study ClC-2 localization and function in the rat retina. RNA encoding ClC-1, -2, -3, -4, and -5 was detected by reverse transcription-PCR in the rat retina. ClC-2-specific antibodies identified protein on cell bodies and in synaptic layers. Double-immunofluorescence staining revealed that intense ClC-2 immunoreactivity colocalized with PKC-stained rod bipolar cells. Patch-clamp experiments performed with individual rod bipolar cells demonstrated the presence of a time-dependent, inwardly rectified current activated at hyperpolarizing membrane potentials. This current demonstrated selectivity for different anions (Cl(-) > I(-) > gluconate), was inhibited by Cd(2+), and was minimally reduced by 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid. These features are consistent with currents generated by ClC-2 channels. Our data indicate that functional ClC-2 channels are present in retinal rod bipolar cells and support a role for ClC-2 in maintaining Cl(-) homeostasis in neurons with ligand-gated chloride channels.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed1996

Prediction of long-term ventilatory support in trauma patients.

Mechanical ventilatory support requiring tracheal intubation may be necessary for variable lengths of time in injured patients. Criteria useful in predicting the need for prolonged tracheal intubation has not been clearly established in the trauma population. Early identification of patients requiring prolonged tracheal intubation and mechanical ventilatory support could lead to earlier tracheostomy and subsequent reductions in complications associated with prolonged endotracheal intubation. This study evaluated the ability of clinical measures of injury severity, mental status, oxygenation, and ventilation to predict the need for prolonged mechanical ventilatory support (> or = 14 days) early in the postinjury course of the adult trauma patient requiring endotracheal intubation and mechanical ventilatory support within the first 24 hours of injury. All adult trauma patients admitted to our Level I trauma center over a 4-year period between January 1990-December 1993 were evaluated. A total of 212 patients met study criteria that included intubation within the first 24 hours of injury, ventilatory support requirement > or = 72 hours, and a survival time of at least 14 days postinjury. Data pertaining to measures of injury severity (RTS, AIS, ISS), mental status (GCS), oxygenation [(A-a)O2], and ventilation (VE,EDC) were recorded for postinjury Day 1 and Day 5. There were 157 males and 55 females (age range of 16-91 years, mean 39.5 years). Mechanism of injury was blunt in 198 and penetrating in 14 patients. One hundred patients required prolonged mechanical ventilatory support. Data were analyzed by stepwise logistic regression analysis. Age and GCS values on Day 1 predicted the need for long term mechanical ventilatory support in a select group of patients, age 20 and GCS of 3 (P < 0.05). At Day 5, age, GCS, and (A-a)O2 gradient were predictive of the need for prolonged mechanical ventilatory support (P < 0.05). On Day 5, GCS of 3 predicted the need for long-term mechanic al ventilatory support regardless of age or (A-a)O2 gradient. GCS < or = 5 and (A-a)O2 > or = 150 predicted prolonged mechanical ventilatory support in young patients (age 20). At ages of 40 to 60, GCS < or = 7 and (A-a)O2 > or = 150 indicated the need for long term mechanical ventilatory support. In older patients (age > or = 80), GCS < or = 7 and (A-a)O2 gradient > or = 100 were predictive of long-term mechanical ventilatory support. Appropriate use of these clinical indicators may assist in early identification of patients requiring prolonged mechanical ventilatory support, and subsequent conversion from endotracheal intubation to tracheostomy with anticipated reduction in complications.

Adolescent↗
PubMed1986

Amsacrine-associated cardiotoxicity: an analysis of 82 cases.

Amsacrine is an antileukemia drug being widely used in North America, Europe, Australia, and New Zealand. In the initial clinical trials, patients treated with amsacrine developed occasional instances of acute cardiac arrhythmias and cardiomyopathy. We review and analyze the features of cardiac abnormalities associated with amsacrine in 82 patients, 27 of whom have not been previously reported. The rest have been reported in the literature, but we have included a large amount of additional information about these patients in our analysis. We conclude that amsacrine-related cardiac events are less common than those related to anthracycline chemotherapeutic agents. Manifestations of such toxicity include ECG abnormalities, ventricular and atrial arrhythmias, sudden death, and congestive heart failure. There is little or no cumulative dose effect. Hypokalemia may be a risk factor for development of serious tachyarrhythmias, but such problems can occur despite a normal serum potassium level. Amsacrine appears to affect depolarization and repolarization of the heart, but the mechanism is unknown.

Adolescent↗