Search PubMed⌕ Search

Biomedical subjects

P Higgins

Publications and source records attributed to P Higgins.

At least 19 recordsLinked to original sources

Role of C3 cleavage in monocyte activation during extracorporeal circulation.

BACKGROUND: We previously demonstrated that inhibiting formation of terminal complement components (C5a and C5b-9) prevents platelet and neutrophil (PMN) but not monocyte activation during simulated extracorporeal circulation (SECC). This study examined whether earlier complement inhibition during SECC, blocking C3a formation, would additionally prevent monocyte activation. METHODS AND RESULTS: SECC was established by recirculating heparinized whole blood from human volunteers on a membrane oxygenator. CAB-2, a chimeric protein constructed from genes encoding the complement regulatory proteins CD46 and CD55, inactivates the C3/C5 convertases and blocks in vitro generation of C3a, C5a, and C5b-9. CAB-2 was used in 4 experiments at a final concentration of 300 micrograms/mL and 4 experiments at 30 micrograms/mL; 4 control runs used vehicle alone. Samples were assayed for C3a and C5b-9, monocyte activation (CD11b upregulation), PMN activation (CD11b upregulation and elastase release), and platelet activation (P-selectin expression and monocyte-platelet conjugate formation). CAB-2 at both doses significantly inhibited formation of C3a and C5b-9 during SECC. High-dose CAB-2 significantly blocked monocyte and PMN CD11b upregulation and PMN elastase release. CAB-2 also inhibited formation of platelet activation-dependent monocyte-platelet conjugates. CONCLUSIONS: Blockade of complement activation early in the common pathway inhibited monocyte CD11b upregulation during SECC, suggesting that early complement components contribute most to monocyte activation during SECC. As expected, PMN and platelet activation were blocked by terminal complement inhibition. This investigation further elucidates the relation between complement and blood cell activation during simulated cardiopulmonary bypass.

Blood Platelets↗

Effects of immune complex formation and complement activation on circulating platelets in the primate.

Primate platelets are different from rodent and rabbit platelets in that they do not express receptors for C3a or C5a or immune adherence receptors. This study assessed the effects of immune complex (IC)-induced complement activation on primate platelets in the circulation. Cynomolgus monkeys (CYN, N = 4) immunized to bovine gamma globulin (BGG) were infused with BGG over 5 min to induce acute intravascular IC formation and complement activation. The studies were carried out under normal complement conditions (N = 12), partial complement inhibition (CAB-2 treated, N = 3), or total complement inhibition (CVF treated, N = 1). Under normal complement conditions, BGG infusion increased C3a levels from undetectable to an average of 11.9 +/- 2.6 micrograms/ml. At this time, decreases occurring in both circulating neutrophils (85 +/- 6%) and monocytes (78 +/- 6%) were significantly greater than decreases in circulating platelets (13 +/- 3%, p < 0.001). Partial complement inhibition had an equivocal effect on the BGG-induced changes in circulating leukocytes, while total complement inhibition abrogated these changes. In contrast, platelet changes were unaffected by complement inhibition. We conclude that, compared to circulating leukocytes, circulating platelets are insensitive to intravascular complement activation induced by IC in the nonhuman primate. These results contrast with previous studies in rodents which demonstrate strong effects of IC-induced intravascular complement activation on both circulating neutrophils and platelets.

Animals↗

Intact proprioception and control of labour pain during epidural analgesia.

BACKGROUND: Accurate proprioception is critical while walking, yet an ambulatory epidural regimen that provides adequate analgesia for labour while simultaneously preserving proprioceptive input has not been described. METHODS: Sixty primigravidae in established labour received bupivacaine 15 mg (15 ml of 0.1% w/v) and fentanyl 100 micrograms through a lumbar epidural catheter. Clinical assessment of dorsal column sensory function included: vibration sense, distal proprioception and the Romberg test, and were all performed before catheter insertion and 30 min after the study bolus. Sensory modalities were also tested compared to an unblocked dermatome. Pain was scored on a 0-10 cm visual analogue scale (VAS) before and 30 min after induction. Intensity of the motor block was tested using a modified Bromage score (grade 1-6). RESULTS: The study bolus provided reliable analgesia with 43 parturients attaining a VAS pain score of zero. Mean duration of analgesia was 67.5 min (SD 22.85). All parturients retained the ability to perform a partial knee bend while standing (grade 6). No mothers exhibited impaired distal proprioception, altered vibration sense or a positive Romberg sign. CONCLUSION: This study confirms that the addition of lumbar epidural fentanyl 100 micrograms to 15 mg of epidural bupivacaine provides good control of labour pain with no motor block and establishes that this combination preserves dorsal column sensory function.

Adult↗

Fibromyalgia and women's pursuit of personal goals: a daily process analysis.

For 30 days, 50 women with primary fibromyalgia syndrome reported daily progress and effort toward a health-fitness and a social-interpersonal goal and the extent to which their pain and fatigue hindered their accomplishment. They also carried palmtop computers to assess their sleep and their pain, fatigue, and positive and negative mood throughout the day. Analyses of the person-day data set showed that on days during which pain or fatigue increased from morning to evening, participants perceived their goal progress to be more attenuated by pain and fatigue. Unrestorative sleep the night before predicted the following day's effort and progress toward accomplishing health-fitness goals, but not social-interpersonal goals. Finally, participants who reported more progress toward social-interpersonal goals on a given day were more likely to evidence improvements in positive mood across the day, regardless of any changes in pain or fatigue that day.

Adaptation, Psychological↗

Anaesthetic depth at induction. An evaluation using clinical eye signs and EEG polysomnography.

We describe the stages of non-REM sleep induced by anaesthesia with sevoflurane 8% in oxygen and relate these stages to clinical eye positions. We explored John Snow's observation (1847) that 'when voluntary movement ceases, with the eyes fixed in an upward gaze during the gas induction of anaesthesia, the patient is protected against the risk of mental suffering' (awareness). Unpremedicated ASA 1 patients undergoing elective tonsillectomy were studied using EEG polysomnographic principles and clinical eye movement tracking. The results expressed as median and range were: latency to stage 1 sleep 4.5 min [2.5-7.5], stage 2 sleep 5 min [3.5-8.5], stage 3 sleep 5.5 min [4-12] and stage 4 sleep 6 min [4.5-15.5]. Eye position 5, the point of no further eye movement, was reached after 9 min [5.5-18.5]. This was significantly longer than the time taken to reach the stage 4 sleep EEG, p < 0.01, supporting Snow's observation and encouraging investigation into eye movement tracking technology as a potential monitor of anaesthetic depth.

Adolescent↗

A dual pathway model of daily stressor effects on rheumatoid arthritis.

This study evaluated the initial promise of a dual-pathway conceptual model linking daily event stressors to rheumatoid arthritis (RA) disease activity through changes in immune system activation and mood. Fifty individuals, who were studied on five occasions two weeks apart, reported daily event stressors on the Daily Life Experience Checklist, daily mood on an abbreviated version of the Profile of Mood States-B, and daily joint pain on the Rapid Assessment of Disease Activity in Rheumatology. Serial clinical examinations comprised ratings of joint tenderness and swelling, and blood drawn during exams was analyzed for sedimentation rate (an indicator of systemic inflammation) and soluble interleukin-2 receptors (a marker of immune system activation known to correlate with RA disease activity). Across-person analyses failed to establish links from daily event stressors to either disease activity or composites of joint pain and joint inflammation when associations were adjusted for the effect of neuroticism on self-report measures. Pooled within-person analyses, however, were generally consistent with the relations predicted by the dual-pathway model. Increases in daily event stressors during the week preceding each clinical exam were associated with increased joint pain (regardless of changes in mood). At the same time, increased daily stressors were indirectly associated with decreased joint inflammation through reduction in levels of soluble interleukin-2 receptors. The dual-pathway model, which may be limited to short-term psychological and psychoimmunologic processes, underscores the importance of distinguishing potentially opposing effects of stress on pain versus inflammation in individuals with rheumatoid arthritis.

Activities of Daily Living↗

Clonidine at induction reduces shivering after general anaesthesia.

PURPOSE: Postanaesthetic shivering occurs in 5-65% of patients. In addition to causing discomfort, it is associated with deleterious consequences. Our objective was to investigate the effect of 150 micrograms clonidine, at induction of anaesthesia, on perioperative core and peripheral temperature, incidence of postanaesthetic shivering and patients' perception of cold. METHODS: Sixty ASA 1 or 2 patients scheduled for elective orthopaedic limb surgery were randomly allocated to group 1, who received 150 micrograms clonidine iv, or group 2, who received a saline bolus iv, before induction. In all patients, anaesthesia was induced with fentanyl and propofol and maintained by spontaneous respiration (via a laryngeal mask airway) of oxygen, nitrous oxide and enflurane. Core (nasopharyngeal) and peripheral (dorsal hand) temperatures were recorded at induction and 15-min intervals. Nurses, unaware of the treatment groups, recorded visible shivering in the recovery room. When cognitive function returned, patients were asked to grade their perception of cold on a 10 cm linear analogue scale, higher scores indicating heat discomfort. RESULTS: While core temperature decreased and peripheral temperature increased in both groups, there was no difference between the groups at any time. However, there was a lower incidence of shivering in the clonidine group (20% vs 66.7%, P < 0.001). Patients receiving clonidine felt warmer; thermal comfort score (median interquartile range) 5.9 (5.0-7.2) vs 5.0 (4.5-6.0), P < 0.05). CONCLUSION: Clonidine 150 g iv at induction of anaesthesia reduces the incidence of shivering and patients' subjective perception of cold on emergence from general anaesthesia.

Adolescent↗

Prevention of spinal anesthesia-induced hypotension in the elderly: comparison between preanesthetic administration of crystalloids, colloids, and no prehydration.

The practice of routinely prehydrating patients by infusing a crystalloid or colloid solution (up to 1.0 L/70 kg) for prevention of spinal anesthesia-induced hypotension has been challenged recently, after several reports of failure to demonstrate its efficacy in young women. We compared the incidence and frequency of hypotension and vasopressor therapy after spinal anesthesia and no prehydration with crystalloid and colloid prehydration in elderly patients. Eighty-five ASA grade I or II patients (aged 60-89 yr) for elective total hip replacement were randomized to receive 500 mL crystalloid solution (Hartmanns, n = 29), 500 mL colloid (Haemaccel, n = 28), or no prehydration (n = 28) over 10 min prior to spinal anesthesia. Hypotension was defined as a 30% decrease from baseline systolic blood pressure (BP) or systolic < 90 mm Hg, and was treated with ephedrine 3-mg boluses. Although absolute systolic BP readings were significantly higher in the colloid group between 6 and 30 min (P < 0.05), the incidence of hypotension was not significantly different between the groups. The incidence of ephedrine use, incidence of nausea/vomiting, and median total dose of ephedrine were similar in all groups. We conclude that, in elderly patients undergoing elective procedures, withholding prehydration is not associated with any greater degree of hypotension or need for vasopressor therapy compared with crystalloid or colloid prehydration.

Aged↗

Improved delivery of biocontrol Pseudomonas and their antifungal metabolites using alginate polymers.

Alginate polymer was evaluated as a carrier for seed inoculation with a genetically modified strain Pseudomonas fluorescens F113LacZY, which protects sugar-beet against Pythium-mediated damping-off. F113LacZY survived in alginate beads at 5 log10 CFU/bead or higher counts for 8 weeks of storage, regardless of the conditions of incubation. In plant inoculation experiments, colonisation of the growing area of the root by F113LacZY, derived from alginate beads placed in the soil next to the seed or from an alginate coating around the seeds, was improved compared with application of just free cells of the strain. F113LacZY trapped in alginate beads was an effective producer of antifungal phloroglucinols as indicated by direct HPLC quantification of phloroglucinols and in vitro inhibition of both the indicator bacterium Bacillus subtilis A1 and the pathogenic fungus Pythium ultimum. Alginate polymer represents a promising carrier for the delivery of biocontrol inoculants for root colonisation and production of antifungal metabolites.

Alginates↗

Sequential daily relations of sleep, pain intensity, and attention to pain among women with fibromyalgia.

Fifty women with fibromyalgia syndrome (FS) recorded their sleep quality, pain intensity, and attention to pain for 30 days, using palm-top computers programmed as electronic interviewers. They described their previous night's sleep quality within one-half hour of awakening each day, and at randomly selected times in the morning, afternoon, and evening rated their present pain in 14 regions and attention to pain during the last 30 min. We analyzed the 30-day aggregates cross-sectionally at the across-persons level and the pooled data set of 1500 person-days at the within-persons level after adjusting for between-persons variation and autocorrelation. Poorer sleepers tended to report significantly more pain. A night of poorer sleep was followed by a significantly more painful day, and a more painful day was followed by a night of poorer sleep. Pain attention and sleep were unrelated at the across-persons level of analysis. But there was a significant bi-directional within-person association between pain attention and sleep quality that was not explained by changes in pain intensity.

Adult↗

Facilitating perinatal grieving between the mother and the father.

Society often expects mothers and fathers to share equally in the perinatal grief process because the child was a common bond between them. Unfortunately, in perinatal grief, this is not always the case. The mother and the father can experience incongruent grieving and use discordant coping mechanisms. It is important to evaluate these differences to facilitate communication between the distraught parents. Improved communication can in turn facilitate the grieving process.

Adaptation, Psychological↗

Unique clinical and psychological correlates of fibromyalgia tender points and joint tenderness in rheumatoid arthritis.

OBJECTIVE: We investigated the relationship of fibromyalgia (FM) tender points to other manifestations of rheumatoid arthritis (RA). METHODS: Sixty-seven RA patients completed questionnaires at study entry and described symptoms, emotionally significant events, and mood every evening for 75 days. Joint and tender point examinations were conducted every 2 weeks. RESULTS: Controlling for joint tenderness, the tender point count correlated with the degree of daily stress. Depression was not significantly related when daily stress was controlled for. CONCLUSION: We conclude that FM tender point counts correlate uniquely with RA patients' reports of daily stress.

Adult↗

Person and contextual features of daily stress reactivity: individual differences in relations of undesirable daily events with mood disturbance and chronic pain intensity.

We examined the mood-related and pain-related consequences of daily stressors among 74 individuals with rheumatoid arthritis who supplied daily reports for 75 days. Meta-analyses of time series regression coefficients disclosed a significant same-day relation between events and mood but no consistent effects of events on same-day pain, next-day mood, or next-day pain. With distributional characteristics of the daily data controlled, Ss with more active inflammatory disease showed a greater positive relation of events with same-day and next-day pain, those with a recent history of more major life stressors showed a greater positive relation of events with next-day pain, and those with less social support showed a greater positive relation of events with next-day mood disturbance. Implications of these and other findings for theories of stress and adaptation and the methodological challenges of daily experience research are discussed.

Adult↗

Self-esteem, social support, and satisfaction differences in women with adequate and inadequate prenatal care.

This descriptive, retrospective study examined levels of self-esteem, social support, and satisfaction with prenatal care in 193 low-risk postpartal women who obtained adequate and inadequate care. The participants were drawn from a regional medical center and university teaching hospital in New Mexico. A demographic questionnaire, the Coopersmith self-esteem inventory, the personal resource questionnaire part 2, and the prenatal care satisfaction inventory were used for data collection. Significant differences were found in the level of education, income, insurance, and ethnicity between women who received adequate prenatal care and those who received inadequate care. Women who were likely to seek either adequate or inadequate prenatal care were those whose total family income was $10,000 to $19,999 per year and high school graduates. Statistically significant differences were found in self-esteem, social support, and satisfaction between the two groups of women. Strategies to enhance self-esteem and social support have to be developed to reach women at risk for receiving inadequate prenatal care.

Adult↗

Amnioinfusion: an update.

Amnioinfusion is one of the most innovative techniques of the decade. The authors reviewed current literature, research indications, and nursing implications for amnioinfusion. Current technology has simplified the amnioinfusion procedure. This technique provides both therapeutic and prophylactic regimens for the intrapartum mother and her fetus, and it has many clinical implications for nursing.

Amniotic Fluid↗

Temporal covariation of soluble interleukin-2 receptor levels, daily stress, and disease activity in rheumatoid arthritis.

OBJECTIVE: To examine synchronous changes in soluble interleukin-2 receptor (sIL-2R) levels, daily indicators of emotional stress, joint inflammation, and reported pain in patients with rheumatoid arthritis (RA). METHODS: Fourteen patients were studied on each of 6 occasions, 2 weeks apart. Measures included daily ratings of mood disturbance, undesirable events, and joint pain; clinical examination of joint swelling; and serum assays of sIL-2R. Pooled within-person correlations among these variables were calculated. RESULTS: Consistent with the results of previous research, joint inflammation covaried directly with sIL-2R levels. Changes in mood disturbance were unrelated to changes in joint inflammation, but increases in mood disturbance were linked with decreases in sIL-2R levels and increases in reported joint pain. CONCLUSION: These findings provide preliminary evidence that psychoimmune processes may be implicated in short-term changes in RA disease activity.

Adult↗