Experiences of Urban African Americans with Cancer Pain

The experience of cancer pain is poorly understood from the perspective of African Americans, who experience higher levels of pain, more pain-related distress, and poorer function than Caucasians. Decreased perceived control over pain may play a greater role for African American patients, affecting pain-related distress and function. The purpose of this study was to add to the understanding of cancer pain and perceived control over pain in African Americans, from the patients’ perspective. This qualitative inquiry was part of a larger mixed-methods study testing an intervention to improve pain, pain-related distress, and functional status through increasing perceived control over pain. Participants were recruited from the waiting room of an urban comprehensive cancer and interviewed in their homes. Interviews with 18 adult cancer patients who self-identified as African American and reported experiencing moderate to severe pain (>4 on a 0–10 scale) within the past two weeks were included. Qualitative interviews were audiotaped, transcribed, and analyzed using a constant comparative method. Two major themes emerged from this qualitative inquiry: struggles of the chronic pain experience and benefits of perceived control over pain. Each theme contained several categories. The study unveiled the participants account of both struggles of the chronic pain experience and barriers of perceived control that can be assessed for and targeted in nursing intervention. Benefits to having perceived control over pain were also illustrated in the participants’ narratives.     

Sensitivity of the SCI-FI/AT in Individuals With Traumatic Spinal Cord Injury

Objective

To examine the ability of the Spinal Cord Injury-Functional Index/Assistive Technology (SCI-FI/AT) measure to detect change in persons with spinal cord injury (SCI).

Relation between functional response to nitroglycerin and extent of myocardial necrosis in dogs: mapping of the left ventricle by 2-dimensional echocardiography

The relation between functional response to brief nitroglycerin infusions and extent of myocardial damage was studied sequentially in closed-chest dogs with acute occlusion of the left anterior descending coronary artery. Two-dimensional echocardiography was used to derive segmental left ventricular (LV) function (systolic fractional area change and systolic wall thickening), and this function was compared with the extent of necrosis measured 5 hours after occlusion in equivalent segments of corresponding pathologic slabs. Two-dimensional echocardiographic study before the dogs were killed indicated that remote nonnecrotic segments always responded to nitroglycerin by significant augmentation of segmental LV function. Segments in which necrosis was less than 40% showed a significant nitroglycerin-induced potentiation in segmental LV function. In contrast, segments in which necrosis was greater than 60% had no potentiation with nitroglycerin. In those segments in which eventual necrosis was 60 to 80%, significant nitroglycerin-induced augmentation in segmental LV function was observed only before and 30 minutes after the coronary occlusion. When the degree of necrosis was greater than 80%, no significant potentiation of segmental LV function was observed even as early as 30 minutes after occlusion. Thus, the degree of nitroglycerin-induced potentiation of segmental cardiac function is closely associated with the extent of myocardial necrosis in the particular ventricular segment. Two-dimensional echocardiography coupled with a nitroglycerin potentiation test might be useful for assessment of the viability of ischemic myocardium.     

Acute coronary occlusion: prolonged increase in collateral flow following brief administration of nitroglycerin and methoxamine.

Regional coronary blood flow was determined with the radioactive microsphere technique 10 an 70 minutes and 2 1/2 and 5 hours after abrupt occlusion of the left anterior descending coronary artery in 12 closed chest sedated dogs. In six dogs, nitroglycerin, 200 to 400 microng/min, was infused intravenously 10 to 70 minutes after occlusion. Methoxamine was administered to return blood pressure and heart rate to prenitroglycerin levels. Ten minutes after occlusion (before treatment) collateral flow values and ischemic zone endocardial/epicardial flow ratios were equivalent in untreated (0.11+/-0.03 ml/min per g; 0.31+/-0.05) and treated dogs (0.14+/-0.02 ml/min per g; 0.29+/-0.03). In untreated dogs, collateral flow did not change over 5 hours; the endocardial/epicardial flow ratio was decreased at 5 hours (0.21+/-0.05, P less than 0.05). In contrast, in treated dogs, collateral flow and the endocardial/epicardial flow ratio were increased at 70 minutes (0.27+/-0.04 ml/min per g, P less than 0.05; 0.53+/-0.10, P less than 0.05). Most importantly, collateral flow remained elevated 5 hours after occlusion (0.26+/-0.03 ml/min per g, P less than 0.05) although treatment was discontinued 70 minutes after occlusion. Hence, collateral flow was unchanged over 5 hours of occlusion in untreated dogs, but short-term treatment with nitroglycerin and methoxamine resulted in a sustained increase in collateral flow. These findings may be a result of stimulation by nitroglycerin and methoxamine of the spontaneous rate at which intrinsic collateral function increases after ischemia. Alternatively, nitroglycerin and methoxamine may maintain cell viability until collateral vessels develop spontaneously.     

Atrial excitability and conduction in patients with interatrial conduction defects

Prolongation of P-wave duration is an accepted indicator of an interatrial conduction disturbance and may predispose patients to atrial arrhythmias. This study was performed to monitor electrophysiologic characteristics of the atria in patients with a prolonged P-wave duration. Atrial excitability and conduction times were compared in 7 patients with a P-wave duration < 115 ms (Group I) and 13 patients with a duration ≥ 115 ms (Group II). In contrast to the Group I patients, most of the 13 patients in Group II had atrial arrhythmias, including sinus nodal dysfunction (3 patients) and a history of atrial fibrillation or ectopic atrial tachycardia (6 patients). Electrophysiologic differences between the 2 groups included a higher late diastolic threshold in Group II (0.8 ± 0.2 mA versus 1.3 ± 0.2 mA; p < 0.005), and a greater increase in intraatrial conduction time (5 ± 10 ms versus 30 ± 20 ms; p < 0.005) and interatrial conduction time (5 ± 15 ms versus 30 ± 15 ms; p < 0.05) of early premature responses. There were no differences between the 2 groups in refractory periods, shape of the strength interval curve, or conduction times of premature responses occurring late in diastole.

These abnormalities in conduction time and excitability found in patients with a prolonged P-wave duration may predispose to the initiation of certain atrial tachyarrhythmias.     

Recent studies on the chemistry of human, bovine and porcine parathyroid hormones

The amino acid sequence of the NH₂-terminal 34 residues of human parathyroid hormone (PTH) has been determined and duplicated synthetically to produce a peptide that is biologically active. In the amino acid sequences of the bovine and porcine hormones, the glutamic acid function at position 22 has been revised to glutamine. Among these initial 34 residues, human PTH differs from bovine PTH by 5 residues and from porcine PTH by 4 residues. Native human PTH and the synthetic human PTH (1–34) peptide are not rigid structures, and significant changes in conformation were observed during pH titration. In addition, at physiologic pH, native human PTH appeared to differ in structure from human PTH (1–34) in the region of the tryptophan residue (residue 23). The fluorescence spectrum of human PTH revealed a maximum at 344 nm, but the spectrum of human PTH (1–34) had a peak at 343 nm; the spectrum of human PTH (1–34) was normalized to 346 nm in 6 M guanidine hydrochloride, but there was no shift with the intact hormone. Fluorescence titration of human PTH in the alkaline region revealed no loss of tryptophanyl fluorescence in aqueous solution or in 6 M guanidine hydrochloride. The synthetic human PTH (1–34) peptide, however, showed an approximately 25 per cent loss of indole fluorescence during alkaline titration which could be normalized with denaturing reagents. These studies suggest that synthetic fragments of the native hormone may not have the same tertiary conformation as the same sequence in the intact hormone. These findings may be of major significance with regard to the biologic activity and immunologic cross reactivity of synthetic fragments and the native hormone.     

Comparison of effectiveness of thyrotropin-suppressive doses of d- and l-thyroxine in treatment of hypercholesterolemia

In an attempt to compare the cholesterol-lowering effects of equivalent doses of d- and l-thyroxine, 10 euthyroid, hypercholesterolemic subjects were treated with graded doses of each medication in a cross-over design using thyrotropin suppression following thyrotropin-releasing hormone administration as the end-point. The mean thyrotropin-suppressive dose of d-thyroxine was 2.4 ± 0.66 mg per day, which resulted in mean reductions of 10 percent in total plasma cholesterol, 10 percent in plasma low-density lipoprotein cholesterol, and 11 percent in plasma high-density lipoprotein cholesterol. The mean thyrotropin-suppressive dose of l-thyroxine was 135 ± 46 μg per day, which resulted in mean reductions of 7 percent in total plasma cholesterol, 6 percent in plasma low-density lipoprotein cholesterol, and 14 percent in plasma high-density lipoprotein cholesterol. The reductions in total, low-density, and high-density cholesterol achieved with d-thyroxine were not significantly different from those achieved with l-thyroxine. Neither medication produced a significant increase in heart rate or ventricular ectopy as determined by Holter monitoring. These data do not support the belief that d-thyroxine has a preferential cholesterol-lowering effect in humans when compared with equivalent doses of l-thyroxine. In addition, both d- and l-thyroxine reduced plasma high-density lipoprotein cholesterol.     

Chronic airflow obstruction in Fabry's disease

Seven patients with Fabry's disease, an x-linked sphingolipid storage disorder, were evaluated for the presence and extent of airway obstruction. All were found to have significant obstruction to airflow. In addition, evaluation of their airway epithelial cells obtained by bronchoscopy demonstrated that these cells contained inclusion bodies consistent with deposits of ceramide trihexoside, suggesting that part of their functional obstruction to airflow may be secondary to intrinsic airway disease. Although all of the study population had evidence of airflow obstruction, the impairment was much worse in those who smoked, implying that even mild cigarette smoking is particularly hazardous to patients with Fabry's disease.     

Sequential chemotherapy and late intensification for malignant lymphomas of aggressive histologic type

Fifty-six patients with malignant lymphoma of aggressive histologic type (51 large cell, three diffuse undifferentiated, and two nodular mixed) were treated with three non-cross-resistant combination chemotherapy regimens that were introduced sequentially according to the response to therapy. The objective was to increase the complete remission rate by changing the chemotherapy regimen early if the patient did not attain a complete remission after three courses of treatment. Late intensification was also used with the aim of prolonging the duration of complete remission. The overall complete remission rate obtained with this approach was 82 percent (100 percent in stages I to III and 66 percent in stage IV). The projected survival at four years is 71 percent (93 percent for stages I to III and 55 percent for stage IV). Eighty percent of patients with complete remission are projected to have continued remission at four years. Compared with previous experience with Adriamycin-based combination regimens, these results represent an improvement in remission and survival parameters. The most significant gains occurred in the prolongation of survival of patients with stages I to III disease and in the improved duration of complete remission of patients with stage IV disease. Toxicity included 15 documented infections among 320 courses of therapy, four cases of congestive heart failure, one case of bleomycin lung toxicity, and two cases of liver dysfunction. This multiple combination regimen represents an improvement over previous results utilizing Adriamycin-based combination chemotherapy.