Biomedical subjects

P B Jacobsen

Publications and source records attributed to P B Jacobsen.

At least 19 recordsLinked to original sources

PubMed2005

Pilot study of a home-based aerobic exercise program for sedentary cancer survivors treated with hematopoietic stem cell transplantation.

We report a pilot study of a home-based aerobic exercise program in a group of 17 adult hematopoietic stem cell transplant (HSCT) recipients. Participants had received no cancer treatment for at least 6 months and reported leisure time physical activity less than 20 min per day and fewer than three times a week during the previous month. Following baseline assessments of aerobic fitness, fatigue symptoms, and quality of life, participants were placed on home-based aerobic exercise programs consisting of 20-40 min of activity in the target heart rate zone (40-60% predicted heart rate reserve) delivered in three to five sessions per week for 12 weeks. Subjects were supplied with electronic heart rate monitors and we encouraged program adherence using weekly telephone contacts and exercise diaries. In all, 32 of the 42 qualified candidates consented (acceptance=76%). Of these, 17 kept appointments for baseline assessments, four did not complete the study (attrition=46%), and no exercise-related adverse events were reported. Scores on measures of aerobic fitness, fatigue severity, and physical well-being improved (signed ranks test; P<0.05) during program participation. Our findings suggest that individually prescribed, home-based aerobic exercise is an acceptable, safe, and potentially effective intervention for improving physical functioning and fatigue in sedentary HSCT recipients.

Adult↗

PubMed2005

Characteristics and correlates of cognitive functioning following bone marrow transplantation.

Patients who undergo bone marrow transplantation (BMT) often report cognitive problems following treatment. This study used cognitive tests and a self-report measure of subjective cognitive complaints to determine (1) the rate of objective cognitive impairment in a sample of 65 BMT patients, and (2) the correspondence of patients' cognitive complaints to their actual cognitive performance. At 6 months following BMT, patients were assessed in seven cognitive domains--attention, verbal learning, verbal memory, visual memory, simple executive function, complex executive function, and psychomotor speed. Cognitive complaints were likewise assessed. In all, 51% had at least mild impairment (-1 standard deviation (s.d.) below published norms) in one or more cognitive domains, with 28% demonstrating moderate-to-severe impairment (-2 s.d.). Older patients and patients with lower IQ were more likely to score in the impaired range on objective cognitive tests, with males and the less educated showing trends toward scores in the impaired range. Younger patients made significantly more cognitive complaints. Total cognitive complaints were unrelated to average cognitive performance, and complaints in specific cognitive domains were largely unrelated to objective performance on corresponding domains. Findings suggest that patients who complain about their cognitive performance following BMT differ from those who experience actual deficits.

Bone Marrow Transplantation↗

PubMed2001

Analysis of phospholipid species in human blood using normal-phase liquid chromatography coupled with electrospray ionization ion-trap tandem mass spectrometry.

A narrow-bore normal-phase high-performance liquid chromatography (HPLC) method was developed for separation of phospholipid classes in human blood. The separation was obtained using an HPLC diol column and a gradient of chloroform and methanol with 0.1% formic acid, titrated to pH 5.3 with ammonia and added 0.05% triethylamine. The HPLC system was coupled on-line with an electrospray ionisation ion-trap mass spectrometer. Chromatographic baseline separation was obtained between phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, lyso-phosphatidylcholine, phosphatidylinositol and phosphatidylserine, eluting in that order. The total run time was 30 min. Plasmalogen phosphatidylethanolamine and sphingomyelin, which both are substances with structural similarities to the glycerophospholipids, had similar retention time as phosphatidylethanolamine, but were well separated from the other glycerophospholipid classes. The species from each class were identified using MS2 or MS3, which forms characteristic lyso-fragments. The combination of lyso-fragment mass, molecular ion and chromatographic retention time was used to identify each species, including 20 species of phosphatidylglycerol. The mass spectra obtained for the phospholipid classes are presented. Using this system 17 disaturated phospholipid species not earlier described to be present in blood were identified. The limit of detection varied between different phospholipid classes and was in the range 0.1-5 ng of injected substance.

Chromatography, High Pressure Liquid↗

PubMed2001

Collision-induced dissociation of glycero phospholipids using electrospray ion-trap mass spectrometry.

Characterisation of phospholipids was achieved using collision-induced dissociation (CID) with an ion-trap mass spectrometer. The product ions were compared with those obtained with a triple quadrupole mass spectrometer. In the negative ion mode the product ions were mainly sn-1 and sn-2 lyso-phospholipids with neutral loss of ketene in combination with neutral loss of the polar head group. Less abundant product ions were sn-1 and sn-2 carboxylate anions. CID using a triple quadrupole mass spectrometer, however, gave primarily the sn-1 and sn-2 carboxylate anions together with lyso-phosphatidic acid with neutral loss of water. For the ion trap a charge-remote-type mechanism is proposed for formation of the lyso-phospholipid product ions by loss of alpha-hydrogen on the fatty acid moiety, electron rearrangement and neutral loss of ketene. A second mechanism involves nucleophilic attack of the phosphate oxygen on the sn-1 and sn-2 glycerol backbone to form carboxylate anions with neutral loss of cyclo lyso-phospholipids. CID (MS(3) and MS(4)) of the lyso-phospholipids using the ion-trap gave the same carboxylate anions as those obtained with a triple quadrupole instrument where multiple collisions in the collision cell are expected to occur. The data demonstrate that phospholipid species determination can be performed by using LC/MS(n) with an ion-trap mass spectrometer with detection of the lyso-phospholipid anions. The ion-trap showed no loss in sensitivity in full scan MS(n) compared to multiple reaction monitoring data acquisition. In combination with on-line liquid chromatography this feature makes the ion-trap useful in the scanning modes for rapid screening of low concentrations of phospholipid species in biological samples as recently described (Uran S, Larsen A, Jacobsen PB, Skotland T. J. Chromatogr. B 2001; 758: 265).

Chromatography, High Pressure Liquid↗

PubMed2001

Investigation of binding of 125I-iodixanol to high molecular weight substances after incubation with rat liver homogenates.

PURPOSE: It has recently been shown that incubation of iodixanol in rat liver homogenates resulted in formation of iodixanol metabolites. The present study was performed to see if this incubation resulted in any binding of iodixanol to high molecular weight substances, as such a high molecular weight conjugate of iodixanol theoretically might cause initiation of an immune response against this contrast agent. MATERIAL AND METHODS: 125I-iodixanol was incubated with rat liver homogenates for 1 h at 37 degrees C and 17 h at 25 degrees C followed by analysis of the supernatant fractions using gel-permeation chromatography with on-line radiochemical detection. RESULTS: No traces of radioactivity could be detected in the chromatograms, except at the retention time of free iodixanol. CONCLUSION: No binding of iodixanol to high molecular weight substances could be demonstrated after incubation of iodixanol with rat liver homogenates.

Animals↗

PubMed2001

Progress in understanding fatigue associated with breast cancer treatment.

Fatigue is one of the most common and distressing symptoms reported by cancer patients. This article reviews research that has examined the extent to which breast cancer patients experience fatigue during and following completion of chemotherapy and radiotherapy. The article also addresses methodological issues in the study of fatigue as well as the current status of efforts to prevent or relieve fatigue associated with breast cancer treatment.

Activities of Daily Living↗

PubMed2000

On-line dialysis and quantitative high-performance liquid chromatography analysis of iodixanol in human, rat and monkey plasma.

A fully automated HPLC method for analysing the non-ionic X-ray contrast agent iodixanol in plasma samples, using on-line dialysis for sample preparation, was developed. Optimal conditions were obtained with a static dialysis donor solution of 110 microl and 4 ml of recipient solution (dialysate) pulsed onto a trace enrichment column, giving maximum 55% dialysis efficiency in less than the chromatographic run time of 20 min. Hence, one sample could be dialysed during the analysis of the previous. The maximum load of iodixanol on the trace enrichment column was 3.75 mg. Validation showed that the method was selective for iodixanol, sensitive down to 84 pmol/ml and had a high precision over a linear range up to 320 nmol/ml. Although developed for iodixanol, the method can easily be modified and applied to other substances with similar properties, i.e., substances having low protein binding and high water solubility, but strong enough stationary phase affinity to be retained by an appropriate trace enrichment column.

Animals↗

PubMed2000

Impact of hot flashes on quality of life among postmenopausal women being treated for breast cancer.

Hot flashes are among the most commonly reported symptoms among women who have completed treatment for breast cancer. Relatively little is known, however, about hot flashes among women while they are undergoing breast cancer treatment. The present study investigated the prevalence and severity of hot flashes of women during chemotherapy and radiotherapy for breast cancer. We also sought to identify the medical, demographic, and treatment correlates of hot flashes during treatment and to document the impact of hot flashes on quality of life. Seventy postmenopausal women with breast cancer completed a self-report questionnaire packet during chemotherapy and radiotherapy. Forty percent (n = 28) reported hot flashes during the week prior to assessment. Of the 28 women endorsing hot flashes, 25% (n = 7) rated them as severe, 39% (n = 11) rated them as moderate, and 36% (n = 10) rated them as mild. Women with hot flashes were significantly (p < 0.05) younger and reported significantly (p < 0.001) more fatigue, poorer sleep quality, and poorer physical health compared to women without hot flashes. Multivariate analyses revealed that, even after controlling for relevant medical, demographic, and treatment variables, the prevalence of hot flashes significantly (p < 0.05) predicted poorer sleep quality, more fatigue, and worse physical health. The results indicate that hot flashes are experienced by a sizable percentage of postmenopausal breast cancer patients as they undergo treatment. Hot flashes during cancer treatment appear to have a negative impact upon patient quality of life that may be due, in part, to fatigue and interference with sleep. Future research should seek to evaluate interventions to relieve hot flashes during breast cancer treatment as a means of improving patient quality of life.

Aged↗

PubMed2000

Quality of life after adjuvant chemotherapy for breast cancer.

PURPOSE: To evaluate the quality of life of breast cancer patients previously treated with adjuvant chemotherapy. METHOD: Registry data were used to recruit a sample of breast cancer patients (N = 61; mean age = 51.6 years) with no current evidence of disease who had completed adjuvant chemotherapy between 3 and 36 months earlier (average = 15.87 months). In addition, a peer nomination procedure was used to recruit an age-matched comparison group of women with no history of cancer (N = 59; mean age = 51.5 years). Both groups were mailed a survey to complete that included the Medical Outcomes Study Short Form 36 (SF-36) and the Center for Epidemiologic Studies Depression Scale (CES-D). These data were used to test the hypothesis that breast cancer patients previously treated with adjuvant chemotherapy experience impaired quality of life relative to their peers and to identify demographic and medical factors associated with individual differences in patient quality of life. RESULTS: Consistent with predictions, the postchemotherapy group scored poorer than the noncancer comparison group on the CES-D and on six of the eight subscales as well as the physical component summary scale of the SF-36 (p < 0.05). With regard to individual differences in patient quality of life, younger age and unmarried status were positively related to poorer mental well-being and greater depressive symptomatology (p < 0.05). Time since cancer diagnosis and chemotherapy completion were also positively related to greater depressive symptomatology (p < 0.05). In contrast, none of the demographic or medical variables assessed were related to physical well-being (p > 0.05). CONCLUSIONS: Breast cancer patients appear to experience problems in multiple quality of life domains following the completion of adjuvant chemotherapy treatment. Demographic and medical characteristics explain individual differences in mental but not physical aspects of patient quality of life. These findings demonstrate the need for interventions to improve the quality of life in breast cancer patients previously treated with adjuvant chemotherapy.

Adult↗

PubMed2000

Symptom structure of PTSD following breast cancer.

Identification of posttraumatic stress disorder (PTSD) symptoms and diagnoses in survivors of cancer is a growing area of research, but no published data exist regarding the symptom structure of PTSD in survivors of malignant disease. Findings from investigations of the PTSD symptom structure in other trauma populations have been inconsistent and have not been concordant with the re-experiencing, avoidance/numbing, and arousal symptom clusters specified in DSM-IV. The present study employed confirmatory factor analysis to evaluate the extent to which the implied second-order factor structure of PTSD was replicated in a sample of 142 breast cancer survivors. PTSD symptoms were measured using the PTSD Checklist--Civilian Version (PCL-C). Fit indices reflected a moderate fit of the symptom structure implied by the DSM-IV. These findings provide some tentative support for the DSM-IV clustering of PTSD symptoms and for the validity of cancer-related PTSD.

Adult↗

PubMed2000

NCCN Practice Guidelines for Cancer-Related Fatigue.

These guidelines propose a treatment algorithm in which patients are evaluated regularly for fatigue, using a brief screening instrument, and are treated as indicated by their fatigue level. The algorithm's goal is to identify and treat all patients with fatigue that causes distress or interferes with daily activities or functioning. Management of fatigue begins with primary oncology team members who perform the initial screening and either provide basic education and counseling or expand the initial screening to a more focused evaluation for moderate or higher levels of fatigue. At this point the patient is assessed for the five primary factors known to be associated with fatigue: pain, emotional distress, sleep disturbance, anemia, and hypothyroidism. If any of these conditions are present, it should be treated according to practice guidelines, and the patient's fatigue should be reevaluated regularly. If none of the primary factors is present or the fatigue is unresolved, a more comprehensive assessment is indicated--with referral to other care providers as appropriate. The comprehensive assessment should include a thorough review of systems, review of medications, assessment of comorbidities, nutritional/metabolic evaluation, and assessment of activity level. Management of fatigue is cause-specific when conditions known to cause fatigue can be identified and treated. When specific causes, such as infection, fluid and electrolyte imbalances, or cardiac dysfunction, cannot be identified and corrected, nonpharmacologic and pharmacologic treatment of the fatigue should be considered. Nonpharmacologic interventions may include a moderate exercise program to improve functional capacity and activity tolerance, restorative therapies to decrease cognitive alterations and improve mood state, and nutritional and sleep interventions for patients with disturbances in eating or sleeping. Pharmacologic therapy may include drugs such as antidepressants for depression or erythropoietin for anemia. A few clinical reports of the use of corticosteroids and psychostimulants suggest the need for further research on these agents as a potential treatment modalities in managing fatigue. Basic to these interventions, the effective management of cancer-related fatigue involves an informed and supportive oncology care team that assesses patients' fatigue levels regularly and systematically and incorporates education and counseling regarding strategies for coping with fatigue (Johnson, 1999), as well as using institutional fatigue management experts for referral of patients with unresolved fatigue.

Exercise↗

PubMed1999

Predicting children's sunscreen use: application of the theories of reasoned action and planned behavior.

BACKGROUND: Skin cancer remains the most common form of cancer in the United States despite the fact that most cases can be prevented by limiting sun exposure. Childhood and adolescence are periods of life during which prolonged sun exposure is particularly common. Accordingly, promoting sun-protective behaviors during these formative years can be of critical importance in preventing skin cancer. The present study applied the theories of reasoned action and planned behavior to the understanding of children's sunscreen use. Based on these theories, it was hypothesized that attitudes, subjective norms, and perceived behavioral control would be related to intentions to use sunscreen, which, in turn, would be related to actual sunscreen use. METHODS: Questionnaires measuring sun-related attitudes, beliefs, perceived control, and intentions were administered to 199 fourth graders (ages 9 to 13, mean = 10.3) attending public schools in Florida. Self-report measures of sun-related behavior were administered to the same subjects 1 month later. RESULTS: Results of correlational analyses were consistent with study hypotheses. Higher rates of sunscreen use at follow-up were predicted by stronger intentions to use sunscreen assessed 1 month previously. In addition, stronger intentions to use sunscreen were found to be related to more favorable attitudes toward sunscreen use, stronger beliefs that peers and parents favored sunscreen use, and greater perceptions of personal control in using sunscreen. Path and multiple regression analyses identified direct and indirect relationships among study variables that partially confirmed those predicted by the theories and provided support for the use of an expanded model that included perceived behavioral control. CONCLUSIONS: The present study confirmed hypotheses derived from the theories of reasoned action and planned behavior regarding the relation of attitudes, subjective norms, and perceived behavioral control to sunscreen use among fourth graders. In addition to their theoretical significance, these findings suggest ways to intervene at the individual, classroom, and family levels to promote greater sunscreen use in this age group.

Adolescent↗

PubMed1999

Fatigue and quality of life in breast cancer patients undergoing autologous stem cell transplantation: a longitudinal comparative study.

As more individuals are being treated for cancer with high-dose therapy and autologous stem cell rescue (ASCR), there is growing interest in treatment side effects and their impact on quality of life. The primary aim of this study was to determine if the severity of fatigue and its impact on quality of life is significantly greater in women undergoing ASCR for breast cancer than in women of similar age with no history of cancer. A group of women being treated with ASCR for breast cancer (n = 31) and a group of women of similar age with no history of cancer (n = 49) participated in this study. Patients completed measures of fatigue and psychosocial functioning prior to treatment, midway through treatment, and toward the end of treatment. Healthy comparison subjects completed the same measures three separate times. Breast cancer patients undergoing ASCR reported significantly more frequent fatigue and more severe fatigue than women with no cancer history. In addition, fatigue had a significantly greater impact on daily functioning and quality of life in patients than in women with no cancer history. Fatigue during ASCR for breast cancer was related to both medical factors (i.e., time since transplant) and psychosocial factors. During ASCR for breast cancer, women experience fatigue which is worse than what is "normally" experienced and which interferes with daily functioning and quality of life. Future research should focus on identifying the biological correlates of fatigue, psychological and physiological mechanisms by which fatigue is produced, and interventions to alleviate fatigue.

Adult↗

PubMed1999

Family caregiver quality of life: differences between curative and palliative cancer treatment settings.

To compare the impact of cancer caregiving in curative and palliative settings on family caregiver quality of life (QOL), 267 family caregivers of cancer patients receiving curative treatment were compared to 134 family caregivers of cancer patients receiving palliative treatment through hospice. Both groups completed a demographic profile in addition to two self-report QOL questionnaires. Patient performance status and disease site were also recorded. Family caregivers of patients receiving palliative care had significantly lower QOL scores and lower scores on physical health. Hierarchical multiple regressions showed that after accounting for patient performance status, treatment status accounted for no additional significant variability in QOL scores. After accounting for caregiver level of education, treatment status accounted for no additional significant variability in physical health. These results suggest that the lower QOL scores of caregivers in the palliative setting are a reflection of the patients' poorer performance status. The lower physical health scores of caregivers in the palliative setting appear to be a reflection of their lower educational level. Additional research is needed to evaluate the influence of specific demands of caregiving and emotional distress of the caregiver on caregiver QOL.

Adult↗

PubMed1999

Fatigue in women receiving adjuvant chemotherapy for breast cancer: characteristics, course, and correlates.

This study investigated the characteristics, course, and correlates of fatigue in women receiving adjuvant chemotherapy for breast cancer. Fifty-four patients were assessed before the start of chemotherapy and during the first three treatment cycles. An age-matched sample of women with no cancer history was assessed at similar time intervals for comparison purposes. Results indicated that breast cancer patients experienced worse fatigue than women with no cancer history. These differences were evident before and after patients started chemotherapy. In addition, fatigue worsened among patients after treatment started. More severe fatigue before treatment was associated with poorer performance status and the presence of fatigue-related symptoms (e.g., sleep problems and muscle weakness). Increases in fatigue after chemotherapy started were associated with continued fatigue-related symptoms and the development of chemotherapy side effects (e.g., nausea and mouth sores). These findings demonstrate the clinical significance of fatigue in breast cancer patients before and during adjuvant chemotherapy treatment. Results also suggest that aggressive management of common side effects, such as nausea and pain, may be useful in relieving chemotherapy-related fatigue.

Adult↗

PubMed1999

The Caregiver Quality of Life Index-Cancer (CQOLC) scale: development and validation of an instrument to measure quality of life of the family caregiver of patients with cancer.

Family caregivers have become increasingly responsible for providing home care for cancer patients. Research has documented the distress of family caregivers; however, little has been done to evaluate the broader impact of caregiving on quality of life (QoL). The objectives of this study were to evaluate the reliability and validity of the Caregiver Quality of Life Index-Cancer (CQOLC), a new self-report instrument. Two hundred and sixty-three family caregivers of patients with lung, breast or prostate neoplasms participated. Test-retest reliability was 0.95 and internal consistency was 0.91. As expected, there were moderate correlations with overall mental health (r = 0.64), emotional distress (r = -0.50 to -0.52), burden (r = -0.65) and patient's performance status (r = -0.47) and low correlations with overall physical health (r = 0.13), social support (r = 0.22) and social desirability (r = 0.08). These results show that increased overall mental health is associated with better QoL, while more emotional distress and worsening patient performance status are associated with poorer QoL. Thus, the CQOLC appears to possess adequate validity, test-retest reliability and internal consistency. Future directions include further evaluation of sensitivity to change and factor analysis to determine the principal health-related QoL domains evaluated by the CQOLC.

Activities of Daily Living↗

PubMed1999

Patients' psychosocial concerns following stem cell transplantation.

Information regarding the nature, frequency, correlates and temporal trajectory of concerns of stem cell transplantation (SCT) recipients is critical to the development of interventions to enhance quality of life (QOL) in these individuals. This study examined psychosocial concerns in 110 SCT (87% autologous) recipients drawn from two SCT centers. Participants were a mean of 46 years of age and 17 months post-SCT (range 3-62 months). Information regarding current and past SCT-related concerns, performance status, and demographic characteristics was collected by telephone interview or questionnaire. Recipients reported a wide variety of psychosocial concerns following SCT. Recipients who were younger, female and evidenced a poorer performance status reported a larger number of post-SCT concerns. Examination of the temporal trajectory of concerns suggests that some concerns are salient throughout the course of post-SCT recovery (eg disease recurrence, energy level, 'returning to normal'), some are salient early in the course of recovery (eg quality of medical care, overprotectiveness by others), and others emerge later in the course of recovery (eg feeling tense or anxious, sexual life, sleep, relationship with spouse/partner, ability to be affectionate). Implications for the development of interventions to enhance post-SCT QOL are identified.

Adult↗

PubMed1999

Biotransformation of nonionic X-Ray contrast agents In vivo and In vitro.

Liposomes loaded with the nonionic iodinated contrast agent iodixanol were injected i.v. into monkeys, rats, and dogs, and liver samples were analyzed by HPLC and mass spectrometry. Two metabolites (M1 and M2), with UV spectra identical to those of the iodixanol isomers (exo and endo) and with a mass increase of 162 compared with iodixanol, were detected. Incubations of iodixanol-liposomes or iodixanol in rat liver homogenates resulted in large amounts of iodixanol metabolites, whereas no metabolites were formed in other organ or tissue homogenates. Four groups of unidentified HPLC peaks were detected: M1 and M2 with a relative retention similar to the metabolite peaks of the in vivo samples, and in addition the minor M3 and M4. UV spectrum analysis indicated that M1 and M3 were structurally related to the iodixanol exo-isomer, whereas M2 and M4 were related to the endo-isomer. Mass spectrometry techniques indicated that the metabolites were conjugates containing one or two hexose residues, which by carbohydrate analysis and experiments with concanavalin A-Sepharose and alpha- and beta-glucosidase were shown to be glucose residues bound to iodixanol through O-alpha1-glycoside-like linkages. Metabolites with similar mass increments also were detected for several other nonionic contrast agents after in vitro incubations in liver homogenates. In conclusion, M1 and M3 are conjugates of the iodixanol exo-isomer with one and two glucose adducts, respectively. M2 and M4 are similar conjugates of the iodixanol endo-isomer. This is the first report on hepatic biotransformation of this class of X-ray contrast agents.

Animals↗