PubMed Health⌕ Search

Biomedical subjects

M P Jensen

Publications and source records attributed to M P Jensen.

At least 19 recordsLinked to original sources

Systematic behavior of charge-transfer transitions and energy level variation in soft donor complexes of the trivalent lanthanides.

The systematic behavior of the charge-transfer (CT) energies in mixed 2,2'-bipyridyl (bipy), N,N-diethyldithiocarbamate (Et2dtc-) complexes of the trivalent lanthanides, Ln(Et2dtc)3(bipy), is investigated to understand the electronic structure of f-element complexes containing soft donor ligands. The energies of ligand to Ln3+ CT are extremely low in this system, an effect attributed to the presence of the soft donor ligands. The lowest CT energy level for the Sm3+, Eu3+, and Yb3+ complexes falls into the visible range. In Eu(Et2dtc)(bipy), the Eu3+ ion becomes nonluminescent because the CT energy stretches below the metastable 5D0 electronic state, whereas luminescence from the CT state and the 4f13 (2)F(5/2) state are observed in the Yb compound. The variation in the energy of the lowest level CT transition for the entire Ln(Et2dtc)3(bipy) series has been evaluated using the experimentally determined CT levels of the Sm3+, Eu3+, and Yb3+ compounds based on the systematic behavior of the lanthanides, which is invariant with respect to the type of ligand. The energy difference between the ground electronic states of the lanthanide ions and the ligand-centered valence band may also be calculated from these results.

Journal Article↗

Microsatellites provide insight into contrasting mating patterns in arribada vs. non-arribada olive ridley sea turtle rookeries.

Molecular studies of sea turtles have shown that the frequency of multiple paternity (MP) varies between species, and between rookeries of the same species. This study uses nuclear microsatellite markers to compare the incidence of MP in two neighbouring olive ridley rookeries on the Pacific coast of Costa Rica, with contrasting nesting behaviours -- the 'arribada' population nesting at Ostional and the solitary nesters of Playa Hermosa. Using two highly polymorphic microsatellite markers, we tested 13 nests from each location and found a significant difference (P < 0.001) between the level of MP of the arribada rookery (92%- the highest found for marine turtles) and that of the solitary nesting rookery (30%). Additional analyses based on six microsatellite loci revealed no genetic differentiation between nesting females from the two locations, or between nesting females and attendant males from the Ostional breeding area. Sixty-nine per cent of the nests with MP were fathered by a minimum of three different males, and three nests showed evidence of at least four fathers. The results suggest that the differences observed in levels of MP between arribada and solitary rookeries are due to an effect of abundance of individuals on the mating system. This is supported by a regression analysis combining other paternity studies on sea turtles which shows that levels of MP increase with increasing abundance of nesting females.

Alleles↗

The scope and nature of pain in persons with multiple sclerosis.

Much remains unknown about the scope, nature, and impact of pain on the lives of persons with multiple sclerosis (MS). In the present study, 180 community dwelling adults with MS completed a postal survey that included demographic measures, MS disease measures, and several standardized measures of pain, including pain intensity, variability, location, and pain-related interference. Some 66% of the sample reported pain, 25% of whom reported severe pain. Persons with pain reported an average of 6.6 distinct pain sites. Using the Brief Pain Inventory Interference Scale, the average level of overall pain interference was 3.33 (0-10 scale) in the group reporting pain. The highest levels of pain interference were reported for sleep, recreational activities, and work in and outside the home. Persons with pain were more likely to report greater MS disease severity, poorer psychological functioning, and poorer health than persons with MS but not pain. Persons with pain were also less likely to be employed. These findings are consistent with previous research that shows that pain is common in MS, that it is severe in a substantial subset of these individuals and has the potential to negatively impact physical and psychosocial functioning over and above the effects of MS itself.

Adult↗

Analysis of energy level structure and excited-state dynamics in a Sm 3+ complex with soft-donor ligands: Sm(Et2Dtc)3(bipy).

Using both laser-excited fluorescence and optical absorption methods, we have determined 57 crystal-field (CF) energy levels of Sm 3+ in crystals of Sm(Et2Dtc)3(bipy). The analysis of the energy levels is based on a model Hamiltonian consisting of both free-ion and CF terms. The CF modeling of the experimental energy levels yielded physically reasonable Hamiltonian parameters with a final rms deviation of 17.3 cm(-1). In comparison with Sm 3+ in other hosts, the CF splitting of Sm 3+ in the lattice of Sm(Et2Dtc)3(bipy) is rather weak. The observed fluorescence decay of the 4G(5/2) manifold is single-exponential, with a lifetime of 24.5 mus, indicating only one site of Sm3+ in the lattice. According to the Judd-Ofelt theory, values of three intensity parameters were obtained (Omega(2,4,6) = 1.57, 2.65, and 3.65, in units of 10(-20) cm(-1)). The calculated branching ratios for transitions from the 4G(5/2) manifold are in agreement with experimental values. The calculated radiative lifetime of the 4G(5/2) manifold is 3.24 ms, and the corresponding fluorescence quantum efficiency is only 0.75%. Efficient multiphonon relaxation processes induced by the localized high-frequency vibrational modes in the bipyridyl group may lead to the extremely low quantum efficiency observed. The thermal line broadening and shifts of the 4G(5/2)(1) --> 6F(1/2) transition were observed and fitted very well by the McCumber-Sturge equations with an assumption of Raman phonon scattering processes as the leading relaxation mechanism. The Debye temperature for this crystal is predicted to be 350 K.

Journal Article↗

Chronic pain in individuals with spinal cord injury: a survey and longitudinal study.

STUDY DESIGN: Cross-sectional and longitudinal postal survey. OBJECTIVES: To (1) compare the severity of pain in persons with spinal cord injury (SCI) to national norms, (2) examine the association between pain and measures of (a) psychological functioning, (b) community integration and (c) pain interference with daily activities, and (3) examine the change in the prevalence and intensity of pain over time. SETTING: Community. METHODS: A total of 147 adults with SCI were surveyed twice, 2-6 years apart. Main outcome measures included presence/absence of pain in general and at specific body sites, 0-10 numerical rating scale of average pain intensity, modified Brief Pain Inventory Pain Interference scale, SF-36 Bodily Pain scale, SF-36 Mental Health scale, Community Integration Questionnaire. RESULTS: Pain was more severe, on average, in this sample of patients with SCI than it is in normative samples. The presence of pain was associated with trends towards poorer psychological functioning and social integration, and the intensity of pain was associated with interference with a number of important basic activities of daily living. Little systematic change was found in pain over a 2-6-year-period, although there was evidence that the prevalence of shoulder pain increases over time. CONCLUSION: The current findings underscore the serious nature of pain in persons with SCI and provide additional support for the need to identify effective treatments for SCI-related pain.

Chronic Disease↗

Coping with chronic pain: a comparison of two measures.

Cognitive-behavioral models of chronic pain hypothesize that how a person copes with pain influences how well he or she adjusts to the pain. Several measures have been developed to assess pain coping, but no studies have yet examined whether these measures are complementary or redundant. In the current study, two pain coping measures (the Chronic Pain Coping Inventory, CPCI, and the Coping Strategies Questionnaire, CSQ) were completed by a large number (N=564) of primarily male veterans referred to a chronic pain program. Regression analyses indicated that the CPCI scales did not contribute unique variance to the prediction of depression over and above the CSQ scales. The CSQ Catastrophizing scale was the single most powerful predictor of depression, although several other CSQ scales (Coping Self-Statements, Diverting Attention, and Increasing Behavioral Activities) also contributed. Both the CPCI and the CSQ contributed unique variance to the prediction of disability, although the CPCI scales appear to be more strongly related to disability than the CSQ scales. The CPCI Guarding scale was the single most powerful predictor of disability of all the coping responses assessed in this study. Other scales predicting disability were the CPCI Seeking Social Support, the CSQ Catastrophizing, and the CSQ Increasing Behavioral Activities. While both CSQ and CPCI contribute unique but modest variance to the prediction of pain severity, the CSQ Catastrophizing scale was the single most powerful predictor of pain severity. The findings of this study are consistent with cognitive-behavioral models of pain. Future research will need to determine whether changes in coping responses (catastrophizing and guarding, in particular) merely reflect, or actually influence, adjustment to chronic pain. In the meantime, clinicians would be wise to give these coping responses particular attention in chronic pain programs.

Adaptation, Psychological↗

An activity pacing scale for the chronic pain coping inventory: development in a sample of patients with fibromyalgia syndrome.

Patients with fibromyalgia syndrome (FS) experience a decreased ability to participate in both vocational and avocational activities. Although many treatment programs advocate activity pacing techniques, 'pacing' is a poorly understood concept for which there are no available measures. The present study describes a brief six-item pacing scale that can be administered as part of the Chronic Pain Coping Inventory (CPCI). Preliminary data indicate that this scale is a valid, reliable index of the pacing construct that is associated with physical impairment in patients with FS and is unrelated to simple task persistence.

Adaptation, Psychological↗

Changes in beliefs, catastrophizing, and coping are associated with improvement in multidisciplinary pain treatment.

To examine the associations between changes in cognitions and coping and multidisciplinary pain treatment outcomes, the authors had 141 patients with chronic pain complete measures of adjustment, beliefs, catastrophizing, and coping; in addition, their significant others rated patient physical functioning at pretreatment, posttreatment, and 6- and 12-month follow-ups. Decreases in guarding and resting and in the belief that pain signals damage were associated with decreases in patient disability. Increases in perceived control over pain and decreases in catastrophizing and in the belief that one is disabled were associated with decreases in self-reported patient disability, pain intensity, and depression. The results are consistent with the hypothesis, derived from cognitive-behavioral models of chronic pain, that the outcomes of multidisciplinary pain treatment are associated with changes in patient cognitions and coping responses.

Adaptation, Psychological↗

Health-related quality of life in peripheral neuropathy.

It is now possible for the clinician to use multidimensional measures to assess the quality of life of their patients. Some of the more widely used instruments to measure HRQOL are the Medical Outcomes Study Short Form 36, the Nottingham Health Profile, the Sickness Impact Profile, and the World Health Organization Quality of Life instrument. Potential uses of quality of life assessment tools include: (1) monitoring the health and social status of a given population, (2) evaluating health care policy, (3) conducting clinical trials, (4) assessing the effectiveness of rehabilitation services, (5) justifying the allocation of limited social and health care resources, and (6) tailoring management to the needs of the patient.

Humans↗

Painful diabetic polyneuropathy: epidemiology, pain description, and quality of life.

A prospective survey study was performed in patients with painful diabetic polyneuropathy (PDN) to assess the nature and scope of their pain. Pain associated with diabetic neuropathy is commonly encountered in clinical practice. Yet, little is known regarding the pain experience and impact on quality of life in persons with painful diabetic neuropathy. These 105 patients noted an average of 6/10 pain, most often described as 'burning', 'electric', 'sharp', and 'dull/ache', which, for most, is worse at night time and when tired or stressed. On average, patients reported that the pain caused substantial interference in sleep and enjoyment of life and moderate interference in recreational activities, normal work, mobility, general activity, social activities, and mood. Unexpectedly, a potential genetic predisposition to the development of painful neuropathy was suggested by the fact that a majority (56%) reported a family member with PDN. Thus, this study found that pain associated with diabetic neuropathy is a significant medical issue that has a substantial impact on the quality of life of many people with this condition.

Diabetic Neuropathies↗

The relation between pain beliefs, negative thoughts, and psychosocial functioning in chronic pain patients.

Cognitions and beliefs appear important in predicting adjustment to chronic pain. The current study examines how cognitions and beliefs are related to psychosocial functioning. One hundred and sixty-three chronic pain out-patients were assessed. Regression analyses were performed using scores on the Pain Beliefs and Perceptions Inventory and the Inventory of Negative Thoughts in Response to Pain as predictor variables and responses to the West Haven Yale Multidimensional Pain Inventory as criterion variables. Pain cognitions and pain beliefs were correlated. After controlling for demographics, employment status and pain severity, pain beliefs and cognitions accounted for a significant amount of the variance in general activity, pain interference, and affective distress. Negative cognitions, particularly negative self-statements, were more predictive of outcome than pain beliefs. Although these data are correlational, they provide additional support for a biopsychosocial model of adjustment to chronic pain.

Adaptation, Psychological↗

Do beliefs, coping, and catastrophizing independently predict functioning in patients with chronic pain?

Physical and psychosocial disability in patients with chronic pain have been shown to be associated with patients' pain-related beliefs, tendency to catastrophize, and pain coping strategy use. However, little is known about whether beliefs, catastrophizing, and coping strategies are independently associated with patient adjustment. Identification of specific beliefs, cognitive responses, and coping strategies strongly and independently associated with physical and psychosocial functioning would suggest the importance of targeting those variables for modification in treatment. One hundred sixty-nine patients entering a multidisciplinary pain treatment program completed measures of pain, beliefs, coping, catastrophizing, physical disability, and depression. Principal components analyses were used to create belief and coping components, which were then entered in multiple regression analyses predicting physical disability and depression. Belief scores significantly and independently predicted both physical disability and depression, after controlling for age, sex, pain intensity, catastrophizing, and coping. Coping scores significantly and independently predicted physical disability, but not depression, whereas catastrophizing independently predicted depression, but not physical disability. These findings suggest the importance of targeting specific pain-related beliefs and coping strategies, as well as catastrophizing, for modification in the treatment of patients with chronic pain.

Adaptation, Psychological↗

Course of symptoms and quality of life measurement in Complex Regional Pain Syndrome: a pilot survey.

Few data have been published regarding the natural history, course of symptoms, and quality of life in Complex Regional Pain Syndrome (CRPS). To obtain preliminary data regarding these important issues in CRPS, a set of patient self-report questionnaires were mailed to patients with the diagnosis of CRPS who had been assessed and/or treated at a tertiary university-based pain center in the United States. Self-reports of demographic information, symptoms, the Neuropathic Pain Scale, and a modified Brief Pain Inventory (mBPI) were received from 31 CRPS patients. Approximately 75% of patients reported initial symptoms of pain, swelling, coldness, and color changes. An additional 71% had weakness and inability to move the extremity as initial symptoms. Weakness at some time during their course of CRPS was described by 97%. A majority reported no overall improvement or worsening of symptoms over time (mean 3.3 years). The pain descriptors with the highest mean values were "deep" (6.4/10), "unpleasant" (6.4), "sensitive" (5.7), "surface" (5.4), and "dull" (5.3) pains. Significant sleep disturbance was reported by 80%. CRPS had a severe impact on quality of life, with substantial interference reported in 9 of 10 mBPI activity items by a majority of these patients. These findings should be viewed with caution and should not be generalized to the entire CRPS population because the cohort was small and select. A large multicenter prospective study needs to be performed to validate these preliminary findings.

Adult↗

Chronic phantom sensations, phantom pain, residual limb pain, and other regional pain after lower limb amputation.

OBJECTIVES: To determine the characteristics of phantom limb sensation, phantom limb pain, and residual limb pain, and to evaluate pain-related disability associated with phantom limb pain. DESIGN: Retrospective, cross-sectional survey. Six or more months after lower limb amputation, participants (n = 255) completed an amputation pain questionnaire that included several standardized pain measures. SETTING: Community-based survey from clinical databases. PARTICIPANTS: A community-based sample of persons with lower limb amputations. MAIN OUTCOME MEASURES: Frequency, duration, intensity, and quality of phantom limb and residual limb pain, and pain-related disability as measured by the Chronic Pain Grade. RESULTS: Of the respondents, 79% reported phantom limb sensations, 72% reported phantom limb pain, and 74% reported residual limb pain. Many described their phantom limb and residual limb pain as episodic and not particularly bothersome. Most participants with phantom limb pain were classified into the two low pain-related disability categories: grade I, low disability/low pain intensity (47%) or grade II, low disability/high pain intensity (28%). Many participants reported having pain in other anatomic locations, including the back (52%). CONCLUSIONS: Phantom limb and residual limb pain are common after a lower limb amputation. For most, the pain is episodic and not particularly disabling. However, for a notable subset, the pain may be quite disabling. Pain after amputation should be viewed from a broad perspective that considers other anatomic sites as well as the impact of pain on functioning.

Adult↗

Mycobacterium tuberculosis KatG is a peroxynitritase.

Mycobacterium tuberculosis resides within the highly oxidative environment of the human macrophage and previous reports have indicated that these mycobacteria are susceptible to reactive nitrogen intermediates including peroxynitrite. This work provides evidence that the Mycobacterium tuberculosis hemoprotein KatG acts as an efficient peroxynitritase exhibiting a kapp of 1.4 x 10(5) M-1s-1 for peroxynitrite decomposition at pH 7.4 and 37 degrees C. The ability of KatG to act as a peroxynitritase adds to its growing list of enzymatic activities and may in part explain the ability of Mycobacterium tuberculosis to persist in macrophages.

Bacterial Proteins↗

Pain in persons with cerebral palsy.

OBJECTIVE: To examine the nature and scope of pain in persons with cerebral palsy (CP). DESIGN: Standardized interviews to assess demographics, pain experiences, and the impact of pain on activities. SUBJECTS: Ninety-three adults with CP recruited from medical clinics at the University of Washington and local residential and community housing for persons with developmental disabilities. MAIN OUTCOME MEASURES: Weekly and 3-month pain intensities, chronic pain grade, interference in daily activities caused by pain, and pain-exacerbating and pain-relieving factors. RESULTS: Sixty-two subjects (67%) reported one or more areas of pain of > or =3 months' duration. Lower extremity pain and back pain were the most common complaints. Fifty-six percent of the subjects reporting pain indicated it occurred daily. Mean average pain intensity, graded on a scale of 0 (no pain) to 10 (pain as bad as could be), was 3.16 (SD = 2.45) in the preceding week and 4.45 (SD = 2.34) in the previous 3 months. Approximately 53% of subjects reporting pain indicated their average pain was of moderate to severe intensity (average pain rated as > or =5). Using Von Korff's Chronic Pain Grade classification system, the majority of subjects who reported pain fell into either grade I (low disability, low pain intensity; 51%) or grade II (low disability, high pain intensity; 39%). Subjects reported many factors that exacerbate pain (eg, stress or weather) or decrease it (eg, exercise or rest). CONCLUSIONS: The data suggest that pain is common in adults with CP. In many subjects, pain levels were moderate to intense.

Activities of Daily Living↗

Patient beliefs predict patient functioning: further support for a cognitive-behavioural model of chronic pain.

According to the cognitive-behavioral model of chronic pain, patient beliefs about their chronic pain influence their behavioral and psychological functioning. Previous correlational and longitudinal studies have supported this hypothesis. However, since previous research has relied almost exclusively on patient self-report to assess both beliefs and functioning, shared method variance may explain some of the relationships found. The aim of the current study was to replicate and extend previous research on the relationship between pain beliefs and patient functioning and behavior by assessing the latter based on three sources of information: patient report, spouse report and direct observation. A total of 121 patients with chronic pain completed self-report measures of beliefs and function. Their spouses completed a measure of patient pain behavior, and both participated in a protocol, from which patient pain behaviors were coded by trained observers. Previously reported relationships between patient beliefs about pain and patient-reported functioning were replicated. Measures of patient beliefs were more strongly associated with self-report measures of pain behaviors and functioning than with spouse and observer ratings of patient pain behaviors. However, significant associations between patient beliefs and both spouse- and observer-reported frequency of patient pain behaviors were found. These findings argue for the generalizability of the relationship found between patient beliefs and patient behaviors across assessment domains, and for the continued application of the cognitive-behavioral model to the understanding of patient adjustment to chronic pain.

Adult↗