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C H Moore

Publications and source records attributed to C H Moore.

62 records · Page 4Linked to original sources

Acid-polyacrylamide gel electrophoresis of lysozyme-estrone glucuronide conjugates.

Acid-polyacrylamide gel electrophoresis (acid-PAGE) was used for analysis of lysozyme-estrone glucuronide conjugates. The resolution of the system allowed the identification of individual conjugate families which differed only in the position of acylation or in the number of estrone glucuronide units. Acid-PAGE was a good alternative to denaturing cation-exchange chromatography for the analysis, separation, and small-scale purification of lysozyme-estrone glucuronide conjugates. It revealed the true order of the relative degree of positive charge on the lysozyme-estrone glucuronide conjugates.

Cytochrome c Group↗

Characterization of lysozyme-estrone glucuronide conjugates. The effect of the coupling reagent on the substitution level and sites of acylation.

Estrone glucuronide conjugates of hen egg white lysozyme were prepared by the mixed anhydride and active ester coupling procedures. Both methods gave good yields of conjugates, but the active ester procedure gave a more diverse range of products, making it less suitable for preparing conjugates for homogeneous enzyme immunoassay. Conjugation of lysozyme with estrone glucuronide by the mixed anhydride procedure gave one major derivative exclusively acylated at lysine residue 33 whereas conjugation by the active ester method gave six derivatives which were acylated at one or more of lysine residues 33, 97, and 116. None of the lysine residues 1, 13, and 96, or the N-terminal alpha-amino group, were acylated in any of the conjugates isolated. The correlation of the conjugate structures with the protein environments of the amino groups in the crystal structure of lysozyme suggested that the sites of acylation were determined not only by the chemical nature of the acylating reagent but also by the surface accessibility and nucleophilicity of the individual lysine residues.

Acylation↗

Non-pulsatile circulatory support in 90 cases.

Survival after cardiac arrest is reportably less than 10%; after cardiogenic shock it is less than 50%; and in failure to wean post-cardiotomy (even with centrifugal pumps in several large series) it is only 11-21%. The authors' experience with non-pulsatile circulatory support in 90 consecutive cases from 1986-91 has shown improved survival. The emergent cardiopulmonary bypass system (CPS) was used in 67 of the 90 patients, with 65 patients resuscitated, 34 (51%) weaned, and 19 (28%) transferred to other cardiovascular support therapies. Of the patients weaned or transferred, 34 (51%) survived > 24 hr, and 21 (31%) survived > 30 days. In the current series, 108 major cardiovascular procedures were done during or after CPS implementation. An in-house trained nursing team working with surgeons and perfusionists contributed to early implementation of the CPS and the subsequent improved survival. The BioMedicus centrifugal pump (VAD) was used predominantly for post-cardiotomy failure to wean in 16 patients and as a bridge to transplant in 7 patients. Fourteen patients (61%) were weaned or transplanted. Of these 14 patients, 11 (48%) survived > 30 days. Non-pulsatile circulatory support devices are relatively inexpensive and available to most hospitals. With careful patient selection and early implementation, one can expect survival of 37% of patients who would otherwise not survive.

Assisted Circulation↗

The addition of epinephrine to subarachnoid administered hyperbaric bupivacaine with fentanyl for cesarean delivery: the effect on onset time.

BACKGROUND AND OBJECTIVES: This study examines the effect of epinephrine on the time to achieve a T4 sensory level when added to a hyperbaric bupivacaine-fentanyl mixture for spinal anesthesia. METHODS: Sixty-nine healthy parturients scheduled for elective cesarean delivery were randomly assigned to three groups. All patients were given 9 mg hyperbaric 0.75% bupivacaine with 25 micrograms fentanyl. Group 1 received no epinephrine while Groups 2 and 3 received 100 micrograms and 200 micrograms epinephrine, respectively. Injection of the spinal anesthetic solutions was performed with the patient in the sitting position. Immediately after drug administration, patients were placed supine with their heads elevated on a pillow and 15 degrees of left uterine displacement was maintained. Vital signs and sensory levels were obtained every minute for 10 minutes. RESULTS: In Groups 2 and 3, the mean time to T4 sensory level was significantly longer (6.9 minutes and 6.6 minutes, respectively) than in Group 1 (4.6 minutes). As a subset, patients weighing more than 90.8 kg achieved a T4 sensory level faster than did those weighting less than 90.8 kg (3 minutes and 5.1 minutes, respectively), but in both groups epinephrine prolonged the onset time to T4 (5.8 minutes and 7.3 minutes, respectively). Three patients were excluded because of failure to obtain a T4 sensory level. CONCLUSIONS: The onset time to T4 is related inversely to patient weight, and epinephrine (100 micrograms and 200 micrograms) delays the onset of sensory block to T4 when administered with subarachnoid hyperbaric bupivacaine-fentanyl.

Adult↗

Successful mechanical circulatory support for noncoronary shock.

Mechanically assisted recovery from shock and long-term survival of nontransplant patients with acute noncoronary myocardial decompensation have not been previously reported. We treated nine patients (aged 8 to 53 years) who were referred with acute nonischemic cardiogenic shock (pulmonary capillary wedge greater than 20, cardiac index less than 1.5 L/min/m2, mean blood pressure less than 60 mm Hg, ejection fraction less than 0.3%). Eight patients had viral prodromes, and one patient was peripartum. All patients' lungs were mechanically ventilated, and pharmacologic support failed in all patients. Two patients received steroids. All received mechanical circulatory support. Seven were initially supported with intraaortic balloon counterpulsation pumps. Two patients recovered with intraaortic balloon counterpulsation pumps alone (3 days and 4 days). Four patients received left ventricular assist devices (3, 7, 10, and 79 days), and two received biventricular support devices (10 days and 14 days). One patient was supported with extracorporeal femoral vein-to-femoral artery bypass for 6 days. Four patients required dialysis (4 days to 5 weeks). Seven patients underwent myocardial biopsies, of which three demonstrated acute myocarditis. All patients recovered ventricular function (ejection fraction greater than 0.55%), and all are New York Heart Association functional class I, 7 months to 4 1/2 years after support. Mechanical circulatory assist devices may be lifesaving for patients with acute nonischemic myocardial decompensation. Patients should be supported for at least 2 weeks before transplantation is considered.

Adult↗

Experience and directions using cardiopulmonary support in fifty-three consecutive cases.

Emergency cardiopulmonary support (CPS) was instituted in 53 consecutive patients for acute life threatening pathologies. Indications for CPS deployment were: cardiac arrest, 60% (n = 32); cardiogenic shock, 20.4% (n = 11), supported angioplasty, 13% (n = 7); and adult respiratory distress syndrome, 5.6% (n = 3). Cardiopulmonary support was successfully deployed in 51 of the 53 patients (96%), resulting in a mean blood pressure greater than or equal to 60 mmHg, CO greater than or equal to 3-5 L/min, and partial pressure of oxygen greater than or equal to 100 mmHg, with venous oxygen saturation greater than or equal to 60%. The average time from arrest to CPS deployment was 40 minutes. Seventy-nine major cardiovascular procedures were done in these 51 patients (average, 1.5/patient). The duration of support ranged from 1 to 75 hrs (mean, 16.1 hrs). Twenty-seven patients (53%) were weaned, 13 successfully (32%), with 11 (85%) surviving greater than 24 hrs, and six (46%), greater than 30 days. The other 24 patients (47%) were transferred to other treatment modalities, including cardiac surgery and bridge-to-transplant ventricular assist devices. Four of these patients died (17%), whereas 20 (83%) survived. Of these survivors, 19 (95%) survived greater than 24 hrs, whereas 11 (55%) survived greater than 30 days. The overall survival using the CPS system is 59% short-term (greater than 24 hrs.), and 33% long-term (greater than 30 days). In conclusion, the CPS system is a potent and effective resuscitative tool. It requires transfer to other treatment modalities for survival in most cases.

Adult↗

Plasma concentration profile of epidural alfentanil. Bolus followed by continuous infusion technique in the parturient: effect of epidural alfentanil and fentanyl on fetal heart rate.

BACKGROUND AND OBJECTIVES: A combined bolus and continuous epidural infusion technique of opioid and bupivacaine mixture has been described, although no pharmacokinetic data for this technique exists. The study documents the plasma concentration profile of epidural alfentanil in parturients using this technique, and evaluates the fetal heart rate tracing for associated changes following opioid administration. METHODS: Twenty-four subjects were randomized to receive epidural alfentanil 500 micrograms in 10 mL 0.125% bupivacaine, group A, or fentanyl 50 micrograms in 10 mL 0.125% bupivacaine, group B, as a bolus dose, followed by continuous infusions of alfentanil 20 micrograms/mL in 0.125% bupivacaine (group A) or fentanyl 2 micrograms/mL in 0.125% bupivacaine (group B) for labor analgesia. Plasma drug levels for each group were examined using repeated measures analysis of covariance. RESULTS: Fetal heart rate tracings were recorded throughout the study and were retrospectively analyzed by a "blinded" perinatologist. Data from fetal heart rate tracings were examined by repeated measures analysis of variance. Mean infusion rates were 9.3 +/- 2.1 mL/hour and 9.6 +/- 1.7 mL/hour for groups A and B, respectively. Mean study duration was 3.7 hours in group A, and 3.0 hours in group B. Low plasma levels precluded analysis of fentanyl data. Group A subjects exhibited stability of drug levels over time. Fetal heart rate tracings in 21 patients demonstrated no changes associated with epidural opioid infusion in either group. CONCLUSIONS: With the dosage regimen used in this study, an initial epidural bolus with continuous infusion technique generates a steady state plasma concentration of alfentanil that is below levels associated with direct respiratory depression.

Adult↗