Lumbar Loads and Muscle Activity During Flywheel and Barbell Leg Exercises

ABSTRACT

Sjöberg, M, Eiken, O, Norrbrand, L, Berg, HE, and Gutierrez-Farewik, EM. Lumbar loads and muscle activity during flywheel and barbell leg exercises. J Strength Cond Res 37(1): 27-34, 2023-It is anticipated that flywheel-based leg resistance exercise will be implemented in future long-duration space missions, to counter deconditioning of weight-bearing bones and postural muscles. The aim was to examine low back loads and muscle engagements during flywheel leg press (FWLP) and flywheel squat (FWS) and, for comparisons, free-weight barbell back squat (BBS). Eight resistance-trained subjects performed 8 repetition maximums of FWLP, FWS, and BBS. Motion analysis and inverse dynamics-based musculoskeletal modeling were used to compute joint loads and muscle forces. Muscle activities were measured with electromyography (EMG). At the L4-L5 level, peak vertebral compression force was similarly high in all exercise modes, whereas peak vertebral posteroanterior shear force was greater ( p < 0.05) in FWLP and BBS than in FWS. Among the back-extensor muscles, the erector spinae longissimus exerted the greatest peak force, with no difference between exercises. Peak force in the lumbar multifidus was lower ( p < 0.05) during FWLP than during FWS and BBS. Peak EMG activity in the lumbar extensor muscles ranged between 31 and 122% of maximal voluntary isometric contraction across muscles and exercise modes, with the greatest levels in the lumbar multifidus. The vertebral compression forces and muscle activations during the flywheel exercises were sufficiently high to presume that when implementing such exercise in space countermeasure regimens, they may be capable of preventing muscle atrophy and vertebral demineralization in the lumbar region.

Comparison of Joint and Muscle Biomechanics in Maximal Flywheel Squat and Leg Press

The aim was to compare the musculoskeletal load distribution and muscle activity in two types of maximal flywheel leg-extension resistance exercises: horizontal leg press, during which the entire load is external, and squat, during which part of the load comprises the body weight. Nine healthy adult habitually strength-training individuals were investigated. Motion analysis and inverse dynamics-based musculoskeletal modelling were used to compute joint loads, muscle forces, and muscle activities. Total exercise load (resultant ground reaction force; rGRF) and the knee-extension net joint moment (NJM) were slightly and considerably greater, respectively, in squat than in leg press (p ≤ 0.04), whereas the hip-extension NJM was moderately greater in leg press than in squat (p = 0.03). Leg press was performed at 11° deeper knee-flexion angle than squat (p = 0.01). Quadriceps muscle activity was similar in squat and leg press. Both exercise modalities showed slightly to moderately greater force in the vastii muscles during the eccentric than concentric phase of a repetition (p ≤ 0.05), indicating eccentric overload. That the quadriceps muscle activity was similar in squat and leg press, while rGRF and NJM about the knee were greater in squat than leg press, may, together with the finding of a propensity to perform leg press at deeper knee angle than squat, suggest that leg press is the preferable leg-extension resistance exercise, both from a training efficacy and injury risk perspective.

Documentation of older people's end-of-life care in the context of specialised palliative care: a retrospective review of patient records

Background

Palliative care focuses on identifying, from a holistic perspective, the needs of those experiencing problems associated with life-threatening illnesses. As older people approach the end of their lives, they can experience a complex series of problems that health-care professionals must identify and document in their patients’ records. Documentation is thus important for ensuring high-quality patient care. Previous studies of documentation in older people’s patient records performed in various care contexts have shown that such documentation almost exclusively concerns physical problems. This study explores, in the context of Swedish specialised palliative care, the content of documentation in older people’s patient records, focusing on documented problems, wishes, aspects of wellbeing, use of assessment tools, interventions, and documentation associated with the person’s death.

Methods

A retrospective review based on randomly selected records (n = 92) of older people receiving specialised palliative care, at home or in a palliative in-patient ward, who died in 2017. A review template was developed based on the literature and on a review of sampled records of patients who died the preceding year. The template was checked for inter-rater agreement and used to code all clinical notes in the patients’ records. Data were processed using descriptive statistics.

Results

The most common clinical notes in older people’s patient records concerned interventions (n = 16,031, 71%), mostly related to pharmacological interventions (n = 4318, 27%). The second most common clinical notes concerned problems (n = 2804, 12%), pain being the most frequent, followed by circulatory, nutrition, and anxiety problems. Clinical notes concerning people’s wishes and wellbeing-related details were documented, but not frequently. Symptom assessment tools, except for pain assessments, were rarely used. More people who received care in palliative in-patient wards died alone than did people who received care in their own homes.

Conclusions

Identifying and documenting the complexity of problems in a more structured and planned way could be a method for implementing a more holistic approach to end-of-life care. Using patient-reported outcome measures capturing more than one symptom or problem, and a systematic documentation structure would help in identifying unmet needs and developing holistic documentation of end-of-life care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12904-021-00771-w.

Influence of gravity on biomechanics in flywheel squat and leg press

Resistance exercise on Earth commonly involves both body weight and external load. When developing exercise routines and devices for use in space, the absence of body weight is not always adequately considered. This study compared musculoskeletal load distribution during two flywheel resistance knee-extension exercises, performed in the direction of (vertical squat; S) or perpendicular to (horizontal leg press; LP) the gravity vector. Eleven participants performed these two exercises at a given submaximal load. Motion analysis and musculoskeletal modelling were used to compute joint loads and to simulate a weightless situation. The flywheel load was more than twice as high in LP as in S (p < 0.001). Joint moments and forces were greater during LP than during S in the ankle, hip and lower back (p < 0.01) but were similar in the knee. In the simulated weightless situation, hip and lower-back loadings in S were higher than corresponding values at Earth gravity (p ≤ 0.01), whereas LP joint loads did not increase. The results suggest that LP is a better terrestrial analogue than S for knee-extension exercise in weightlessness and that the magnitude and direction of gravity during resistance exercise should be considered when designing and evaluating countermeasure exercise routines and devices for space.

Abstract 3843: LSD1 modulation by allosteric ligands

LSD1 has emerged as a potential therapeutic target for a number of cancer types (e.g. AML, SCLC, colorectal, breast, liver, prostate, glioblastoma, Ewing sarcoma), as well as sickle cell anaemia and Alzheimer’s disease. Irreversible LSD1 catalytic inhibitors have shown limited clinical efficacy in AML and SCLC, while solid tumours are largely unaddressed. This is in contrast to LSD1 knockdown with impact on a wide range of cancers, indicating that LSD1 functions other than enzymatic should be targeted.

We have developed novel small molecules that modulate LSD1 via an allosteric site - without inhibiting its enzymatic function - inducing a 60% reduction of nuclear LSD1 levels. The sensitivity profile in a cancer cell line panel is unique and dissimilar to &gt;300 diverse reference compounds. In vitro efficacy is observed in glioma-initiating clones that are highly resistant to standard-of-care temozolimide as well as catalytic LSD1 inhibitors. Efficacy in the sub-µM range is observed with other solid tumour models, e.g. prostate cancer. The compounds exhibit synergy (Bliss independence &gt;40%) with HDAC inhibitors as evaluated by viability in cellular cancer models, including lung, liver and glioblastoma.

Pharmacokinetic studies show good blood-brain-barrier penetration and oral availability of the allosteric LSD1 modulator BEA-17. A repeat dose of 25 mg/kg was well tolerated by NOD SCID mice, leading to µM level accumulation in the brain. Results from orthotopic glioblastoma PDX models, and in vivo hollow-fiber models of other solid tumours will be presented, as well as mechanistic insights from biophysical assays and gene expression analysis.

Citation Format: Wei B. Emond, Matthis Geitmann, Malin Jarvius, Konrad Koehler, Per Källblad, Mia Niklasson, Vendela Parrow, Rajiv Sawant, Maria Sjöberg, Johan Winquist, Anna Segerman, Ulf Bremberg. LSD1 modulation by allosteric ligands [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3843.

Transmission of Clostridium difficile spores in isolation room environments and through hospital beds

The aim of this study was to determine the dissemination of Clostridium difficile (CD) spores in a hospital setting where the potassium monopersulfate-based disinfectant Virkon™ was used for cleaning. In the initial part of the study, we sampled 16 areas of frequent patient contact in 10 patient rooms where a patient with CD infection (CDI) had been accommodated. In the second part of the study, we obtained samples from 10 patient beds after discharge of CDI patients, both before and after the beds were cleaned. In the first part, CDspores were isolated in only 30% of the rooms. In the second part, which focused on transmission to hospital beds, C. difficile was found in four of 10 beds either before or after cleaning. In conclusion, in both parts of the study, we demonstrated a moderate spread of CD spores to the environment despite routine cleaning procedures involving Virkon™.

Infliximab as rescue therapy in hospitalised patients with steroid-refractory acute ulcerative colitis: a long-term follow-up of 211 Swedish patients

BACKGROUND

Rescue therapy with infliximab (IFX) has been proven effective in a steroid-refractory attack of ulcerative colitis (UC). The long-term efficacy is not well described.

AIM

To present a retrospective study of IFX as rescue therapy in UC. Primary end points were colectomy-free survival at 3 and 12 months.

METHODS

In this multicentre study, 211 adult patients hospitalised between 1999 and 2010 received IFX 5 mg/kg as rescue therapy due to a steroid-refractory, moderate-to-severe attack of UC. Exclusion criteria were duration of current flare for >12 weeks, corticosteroid treatment for >8 weeks before hospitalisation, previous IFX therapy or Crohn's disease.

RESULTS

Probability of colectomy-free survival at 3 months was 0.71 (95% CI, 0.64-0.77), at 12 months 0.64 (95% CI, 0.57-0.70), at 3 years 0.59 (95% CI, 0.52-0.66) and at 5 years 0.53 (95% CI, 0.44-0.61). Steroid-free, clinical remission was achieved in 105/211 (50%) and 112/209 (54%) patients at 3 and 12 months respectively. Of 75 colectomies during the first year, 48 (64%) were carried out during the first 14 days, 13 (17%) on days 15-90 and 14 (19%) between 3 and 12 months. There were three (1.4%) deaths during the first 3 months.

CONCLUSIONS

Infliximab is an effective rescue treatment, both short- and long-term, in a steroid-refractory attack of UC. Most IFX failures underwent surgery during the first 14 days, which calls for studies on how to optimise induction treatment with IFX. Serious complications, including mortality, were rare.

Hand disinfectant practice: the impact of an education intervention

The primary hypothesis of this study was that a lecture on basic hygiene routines could be associated with an increase in the use of disinfectant for hand hygiene. A secondary hypothesis was that the lecture could positively affect the staff's knowledge of and attitudes toward basic hygiene routines.A quasi-experimental design including one ward of the department of orthopedics in a Swedish university hospital was adopted.During the pre-intervention test period the consumption of hand disinfectant was measured for 30 days and a questionnaire was distributed to all staff. The hospital hygiene nurse subsequently provided a lecture on basic hygiene routines to all employees on the ward. During the post-intervention test period the hand disinfectant consumption was measured for another 30 days, and the questionnaire was distributed once again. A follow-up measurement was performed 9 months after the intervention.After the lecture on hygiene routines, the consumption of hand disinfectant increased by 93%. Nine months after the intervention, the consumption was still 21% higher than before the intervention. The result of the questionnaire showed that the employees considered themselves applying the disinfectant more thoroughly after the intervention. Some employees changed their perspective on basic hygiene routines after the lecture and stopped using watches and private clothes at work.Our findings suggest that a single education session, a hygiene lecture, could be a simple and cost-effective method to increase the use of hand disinfectant, thereby reducing the number of nosocomial infections on the wards.

Febrile Plasmodium falciparum malaria 4 years after exposure in a man with sickle cell disease

We report a case of symptomatic Plasmodium falciparum malaria that manifested 4 years after a visit to an area of endemicity in an 18-year-old male patient with sickle cell disease. The exceptionally long incubation time raises the questions of how and where P. falciparum parasites can reside for several years before suddenly causing disease.

Mechanisms of estrogen receptor signaling: convergence of genomic and nongenomic actions on target genes

Estrogen receptors (ERs) act by regulating transcriptional processes. The classical mechanism of ER action involves estrogen binding to receptors in the nucleus, after which the receptors dimerize and bind to specific response elements known as estrogen response elements (EREs) located in the promoters of target genes. However, ERs can also regulate gene expression without directly binding to DNA. This occurs through protein-protein interactions with other DNA-binding transcription factors in the nucleus. In addition, membrane-associated ERs mediate nongenomic actions of estrogens, which can lead both to altered functions of proteins in the cytoplasm and to regulation of gene expression. The latter two mechanisms of ER action enable a broader range of genes to be regulated than the range that can be regulated by the classical mechanism of ER action alone. This review surveys our knowledge about the molecular mechanism by which ERs regulate the expression of genes that do not contain EREs, and it gives examples of the ways in which the genomic and nongenomic actions of ERs on target genes converge. Genomic and nongenomic actions of ERs that do not depend on EREs influence the physiology of many target tissues, and thus, increasing our understanding of the molecular mechanisms behind these actions is highly relevant for the development of novel drugs that target specific receptor actions.

Estrogen receptor-dependent activation of AP-1 via non-genomic signalling

Background

Ligand-bound estrogen receptor α (ERα) and estrogen receptor β (ERβ) modulate AP-1-dependent transcription via protein-protein interactions on DNA, in a manner that depends on the type of cells and the subtype of ER. We present here evidence for an additional mechanism by which ERs modulate the transcriptional activity of AP-1.

Results

We show that ERs located in the cytoplasm efficiently activate transcription at AP-1 sites in response to 17β-estradiol, while ERs present in the nucleus repress transcription under the same conditions. 17β-estradiol-induced activation of the coll-73-luc reporter correlated with cytoplasmic localization of various ERα and ERβ mutant receptors, and was inhibited in the presence of the full estrogen antagonist ICI 182,780 and the MAP-kinase inhibitor UO126. We also show that the selective estrogen receptor modulator (SERM) tamoxifen is as potent as 17β-estradiol in inducing activation of AP-1 when ERα is present in the cytoplasm.

Conclusions

These results suggest that non-genomic signalling is involved in the mechanism by which ERα and ERβ influence AP-1-dependent transcription. We have previously shown that Stat3 and Stat5 are targeted by non-genomic actions of ERs, and the results presented here allow us to conclude that ERs bound to 17β-estradiol mediate the transcriptional activation of promoters regulated by AP-1 and by Stat proteins via different combinations of signal transduction pathways. Our observations thereby provide new insights into the mechanisms by which ERs act at alternate response elements, and suggest a mechanism by which tamoxifen exerts its action as a tissue-selective agonist.

Mutations in the estrogen receptor DNA-binding domain discriminate between the classical mechanism of action and cross-talk with Stat5b and activating protein 1 (AP-1)

Estrogen receptors (ERs) efficiently potentiate the transcriptional activity of prolactin-activated Stat5b through a mechanism that involves the ER DNA-binding domain (DBD) and the hinge domain. We have identified residues within the DBD of ER that are critical for the functional interaction of ER with Stat5b. We show that disruption of the second zinc finger structure abrogated cross-talk between ER and Stat5b, while the structure of the first zinc finger was not important. Furthermore, we confirm that intact DNA binding activity was not required for potentiation of Stat5b activity and that the dimerization of ER did not seem to be involved. Ligand-bound ERs also modulated activating protein 1-dependent transcription, and our data demonstrate that both zinc finger structures of the ER DBD are important for an intact response. We show that introduction of various point mutations within the DBD altered the response of the receptor to 17beta-estradiol and to the estrogen antagonists 4-hydroxytamoxifen and ICI 182,870 on the collagenase promoter. These findings provide new insights into the mechanisms by which ERs act in cross-talk with non-related transcription factors.

Signal transducers and activators of transcription as downstream targets of nongenomic estrogen receptor actions

17Beta-estradiol-activated estrogen receptor alpha (ERalpha) and beta (ERbeta) are able to induce transcriptional activation of signal transducer and activator of transcription (Stat)-regulated promoters via cytoplasmic signal transduction pathways. Stat5 and Stat3 are required for promoter induction, which correlates with cytoplasmic sublocalization of ERs and is independent of intact coactivator binding sites and DNA-binding domains. In endothelial cells, Stat5 and Stat3 are rapidly phosphorylated on both tyrosine and serine residues in response to 17beta-estradiol, and nuclear translocation is subsequently induced. 17Beta-estradiol-induced transactivation of a Stat-regulated promoter requires at least three different signal transduction pathways, including MAPK, Src-kinase, and phosphatidylinositol-3-kinase activities. In conclusion, this work identifies a novel pathway involving an agonist-bound ER-activated phosphorylation cascade, resulting in nuclear transcriptional activation of target transcription factors. These findings reveal novel targets for the development of drugs that modulate a nongenomic-to-genomic ER-dependent mechanism.

Cross-talk between Stat5b and estrogen receptor-alpha and -beta in mammary epithelial cells

Both 17beta-estradiol and prolactin play important roles in the mammary gland, raising the possibility of functional cross-talk between the two signaling pathways. Here, we demonstrate that estrogen receptor-alpha (ERalpha) and -beta (ERbeta) are both able to potentiate transcription from a Stat5-responsive promoter when activated by prolactin. Potentiation was observed not only in the presence of 17beta-estradiol, but also in the presence of anti-estrogens such as tamoxifen and ICI 182,780. The magnitude of the response was dependent on cell-type: in the HC11 mouse mammary epithelial cell line ERbeta potentiates transcription efficiently whereas ERalpha showed low activity. Conversely, in COS-7 cells, both estrogen receptors were active. We show that activation domains in the N-terminus (AF-1) and the C-terminus (AF-2) of the ERs are dispensable for potentiation. The effects are dependent on the presence of an intact DNA-binding/hinge domain, which we show is capable of interacting with Stat5b in vitro and in HC11 cell extracts. We conclude that ERalpha and ERbeta act as coactivators for Stat5b through a mechanism which is independent of AF-1 and AF-2.

Mechanical strain and estrogen activate estrogen receptor alpha in bone cells

Bone cells' early responses to estrogen and mechanical strain were investigated in the ROS 17/2.8 cell line. Immunoblotting with antiphosphorylated estrogen receptor a (ER-alpha) antibody showed that when these cells were exposed for 10 minutes to estrogen (10(-8) M) or a single period of cyclic dynamic strain (peak 3400 microepsilon, 1 Hz, 600 cycles), there was an increase in the intensity of a 66-kDa band, indicating phosphorylation of ser122 in the amino terminus of ER-alpha. Increased phosphorylation was detected within 5 minutes of exposure to estrogen and 5 minutes after the end of the period of strain. Estrogen and strain also activated the mitogen-activated protein kinase (MAPK) family member extracellular regulated kinase-1 (ERK-1). Increases in ERK activation coincided with increased ER-alpha phosphorylation. Activation of ERK-1 and the phosphorylation of ER-alpha, by both estrogen and strain, were prevented by the MAP kinase kinase (MEK) inhibitor U0126 and the protein kinase A (PKA) inhibitor (PKI). These data support previous suggestions that resident bone cells' early responses to strain and estrogen share a common pathway, which involves ER-alpha. This pathway also appears to involve PKA and ERK-mediated phosphorylation of ser122 within the amino terminus of ER-alpha. Reduced availability of this pathway when estrogen levels are reduced could explain diminished effectiveness of mechanically related control of bone architecture after the menopause.

Docosahexaenoic acid, a ligand for the retinoid X receptor in mouse brain

The retinoid X receptor (RXR) is a nuclear receptor that functions as a ligand-activated transcription factor. Little is known about the ligands that activate RXR in vivo. Here, we identified a factor in brain tissue from adult mice that activates RXR in cell-based assays. Purification and analysis of the factor by mass spectrometry revealed that it is docosahexaenoic acid (DHA), a long-chain polyunsaturated fatty acid that is highly enriched in the adult mammalian brain. Previous work has shown that DHA is essential for brain maturation, and deficiency of DHA in both rodents and humans leads to impaired spatial learning and other abnormalities. These data suggest that DHA may influence neural function through activation of an RXR signaling pathway.

Grey seal, Halichoerus grypus, habitat selection around haulout sites in the Baltic Sea: bathymetry or central-place foraging?

We investigated habitat selection by grey seals, Halichoerus grypus, around haulouts in the Baltic Sea. Home ranges (95% fixed kernel) varied in size from 1088 to 6400 km2. Observed habitat use was tested against the circular home range predicted from a simple central-place model. The overlap between the home ranges predicted by this simple model and actually exhibited by the seals was <70% for 9 of 11 seals. Furthermore, the depth distributions of the utilised areas were significantly different from that available in the circular home range for all 11 seals. Seals selected depths of 11-40 m and avoided areas >51 m deep. Ten of the 11 seals used areas within a 50-km radius around the haulout site for more than 75% of the time. Thus, in spite of their mobility and the availability of many islands, seals usually remained in the vicinity of a specific haulout site for extended periods. The seals did not use the habitat around the haulout site as predicted by the simple central-place model, but selected habitat according to bathymetric characteristics (e.g., water depth). Detection of these relatively small but heavily used home ranges around haulout sites may be of assistance in management plans in order to reduce the growing number of seal-fisheries conflicts.

Evidence for oestrogen receptor alpha-immunoreactivity in gonadotrophin-releasing hormone-expressing neurones

Having used the cingulate cortex to demonstrate the validity of our methods for detecting hitherto unrecognized oestrogen receptor alpha (ERalpha)-immunoreactive neurones, we have now employed immunoprecipitation and double-label immunohistochemistry to investigate whether the ERalpha protein is present in gonadotrophin-releasing hormone (GnRH)-containing cells. The immortalized GnRH cell line GT1-7 and GnRH neurones within the rat preoptic area were found to possess ERalpha-immunoreactivity (ERalpha-IR). These observations indicate that oestrogen may regulate the synthesis and release of GnRH by direct actions on GnRH neurones.

Evidence for extensive distribution of oestrogen receptor alpha-immunoreactivity in the cerebral cortex of adult rats

The presence of oestrogen receptor alpha (ERalpha)-immunoreactivity (IR) in the cerebral cortex of adult rats has been investigated. Previous studies have reported a negligible presence of ERalpha or ERalpha mRNA in this region of the adult rat brain. We have used immunoprecipitation and immunohistochemistry, with various antibodies and fixatives, to detect this protein in the cingulate cortex. When the tissue was fixed using paraformaldehyde alone only faint ERalpha-IR was observed at this site. In contrast, following fixation either with acrolein (with or without paraformaldehyde) or with a mixture of paraformaldehyde and glutaraldehyde there was extensive ERalpha-IR throughout layers II to VI; this was absent when the antibodies were preincubated with the peptide fragment used in their production. The presence of ERalpha-IR in the nonfixed cingulate cortex of adult rats was confirmed by immunoprecipitation.

Competition between thyroid hormone receptor-associated protein (TRAP) 220 and transcriptional intermediary factor (TIF) 2 for binding to nuclear receptors. Implications for the recruitment of TRAP and p160 coactivator complexes

Transcriptional activation by nuclear receptors (NRs) involves the concerted action of coactivators, chromatin components, and the basal transcription machinery. Crucial NR coactivators, which target primarily the conserved ligand-regulated activation (AF-2) domain, include p160 family members, such as TIF2, as well as p160-associated coactivators, such as CBP/p300. Because these coactivators possess intrinsic histone acetyltransferase activity, they are believed to function mainly by regulating chromatin-dependent transcriptional activation. Recent evidence suggests the existence of an additional NR coactivator complex, referred to as the thyroid hormone receptor-associated protein (TRAP) complex, which may function more directly as a bridging complex to the basal transcription machinery. TRAP220, the 220-kDa NR-binding subunit of the complex, has been identified in independent studies using both biochemical and genetic approaches. In light of the functional differences identified between p160 and TRAP coactivator complexes in NR activation, we have attempted to compare interaction and functional characteristics of TIF 2 and TRAP220. Our findings imply that competition between the NR-binding subunits of distinct coactivator complexes may act as a putative regulatory step in establishing either a sequential activation cascade or the formation of independent coactivator complexes.

The first step: activation of the Semliki Forest virus spike protein precursor causes a localized conformational change in the trimeric spike

The structure of the particle formed by the SFVmSQL mutant of Semliki Forest virus (SFV) has been defined by cryo-electron microscopy and image reconstruction to a resolution of 21 A. The SQL mutation blocks the cleavage of p62, the precursor of the spike proteins E2 and E3, which normally occurs in the trans-Golgi. The uncleaved spike protein is insensitive to the low pH treatment that triggers membrane fusion during entry of the wild-type virus. The conformation of the spike in the SFVmSQL particle should correspond to that of the inactive precursor found in the early stages of the secretory pathway. Comparison of this "precursor" structure with that of the mature, wild-type, virus allows visualization of the changes that lead to activation, the first step in the pathway toward fusion. We find that the conformational change in the spike is dramatic but localized. The projecting domains of the spikes are completely separated in the precursor and close to generate a cavity in the mature spike. E1, the fusion peptide-bearing protein, interacts only with the p62 in its own third of the trimer before cleavage and then collapses to form a trimer of heterotrimers (E1E2E3)3 surrounding the cavity, poised for the pH-induced conformational change that leads to fusion. The capsid, transmembrane regions and the spike skirts (thin layers of protein that link spikes above the membrane) remain unchanged by cleavage. Similarly, the interactions of the spikes with the nucleocapsid through the transmembrane domains remain constant. Hence, the interactions that lead to virus assembly are unaffected by the SFVmSQL mutation.

Spectral analysis of heart rate variability in patients with irritable bowel syndrome

BACKGROUND

Autonomic dysfunction, both adrenergic and cholinergic, has been associated with the irritable bowel syndrome (IBS). The accuracy of the methods in use, however, has been limited by the need for active co-operation by the patients, with consequent difficulties in standardization. The aim of this study was to investigate the function of the autonomic nervous system in patients with IBS by using spectral analysis of the heart rate variability, an accurate method depending very little on patient cooperation.

METHODS

Eighteen patients with IBS were compared with 36 sex- and age-matched controls. Spectral analysis of heart rate variability was performed to quantify sympathetic and parasympathetic nerve activity.

RESULTS

The patients with IBS had significantly higher sympathetic activity than controls (P = 0.005). There was no significant (P = 0.308) increase in parasympathetic activity. There were no significant differences in heart rate or blood pressure between the patients and controls.

CONCLUSION

Spectral analysis of heart rate variability has been used to assess the function of the autonomic nervous system in patients with IBS. IBS patients have significantly increased symphathetic activity, whereas parasympathetic activity does not differ from that of controls.

Ligand-independent activation of the oestrogen receptor by mutation of a conserved tyrosine

The oestrogen receptor is a member of the nuclear receptor family of transcription factors which, on binding the steroid hormone 17beta-oestradiol, interacts with co-activator proteins and stimulates gene expression. Replacement of a single tyrosine in the hormone-binding domain generated activated forms of the receptor which stimulated transcription in the absence of hormone. This increased activation is related to a decrease in hydrophobicity and a reduction in size of the side chain of the amino acid with which the tyrosine is replaced. Ligand-independent, in common with ligand-dependent transcriptional activation, requires an amphipathic alpha-helix at the C-terminus of the ligand-binding domain which is essential for the interaction of the receptor with a number of potential co-activator proteins. In contrast to the wild-type protein, constitutively active receptors were able to bind both the receptor-interacting protein RIP-140 and the steroid receptor co-activator SRC-1 in a ligand-independent manner, although in the case of SRC-1 this was only evident when the receptors were prebound to DNA. We propose, therefore, that this tyrosine is required to maintain the receptor in a transcriptionally inactive state in the absence of hormone. Modification of this residue may generate a conformational change in the ligand-binding domain of the receptor to form an interacting surface which allows the recruitment of co-activators independent of hormone binding. This suggests that this tyrosine may be a target for a different signalling pathway which forms an alternative mechanism of activating oestrogen receptor-mediated transcription.

Spinal epidural metastasis: implications for spinal analgesia to treat "refractory" cancer pain

Two hundred one consecutive patients with cancer pain who received intrathecal pain treatment between 1985 and 1993 were included in this retrospective study undertaken to test the hypothesis that epidural metastasis is a common cause of "refractory" cancer pain and that its presence may affect the efficacy and the complication rates of intraspinal pain treatment. Fifty-seven (approximately 28%) patients were investigated by metrizamide myelography, computerized tomography (CT), magnetic resonance imaging (MRI), laminectomy, or neurohistopathology. Epidural metastases were found in 40 (70%) and spinal stenosis in 33 (approximately 58%); 7 patients with total and 26 with partial occlusion of the spinal canal. Presence of epidural metastasis affected catheter insertion complications, daily dosages, and complications of the intrathecal pain treatment only when it was associated with spinal canal stenosis (partial or total). During the period of the intrathecal treatment, the patients with confirmed epidural metastasis and total spinal canal stenosis needed significantly (P < 0.05) higher daily doses of opioid (means = 77 +/- 103 versus 22 +/- 29 mg) and intrathecal bupivacaine (means = 65 +/- 44 versus 33 +/- 20 mg) and had significantly (P < 0.05) higher rates (14% versus 0%) of radicular pain at injection and poor distribution of analgesia than those without epidural metastasis and spinal canal stenosis. In contrast, the rate of occurrence of post-dural puncture headache was significantly (P < 0.05) lower in patients with partial (4%) and total (14%) spinal stenosis than in those without (29%). Unexpected paraplegia occurred in four patients and was due to accidental injury during attempted dural puncture (N = 1) and collapse (due to cerebrospinal fluid leakage leading to "medullary coning" of an unknown epidural metastasis (N = 3).

Ligand-dependent and -independent transactivation by thyroid hormone receptor beta 2 is determined by the structure of the hormone response element

Chicken thyroid hormone receptor beta 2 (cTR beta 2) is likely to serve specific functions in gene regulation since it possesses a unique N-terminal domain and is expressed in very few tissues. We demonstrate here that TR beta 2 exhibits distinct transactivation properties which are dependent on the availability of ligand and on the structure of the hormone response element. First, a strong ligand-independent transactivation was observed with hormone response elements composed of direct repeats and everted repeats. Second, TR beta 2 was induced by triiodothyronine to transactivate more efficiently than TR beta 0 on palindromic and everted-repeat types of hormone response elements. However, coexpression of the retinoid X receptor reduced the strong transactivation by TR beta 2 but not by TR beta 0 via palindromic response elements, suggesting that TR beta 2 can transactivate as a homodimer. Finally, the N terminus of TR beta 2 contains two distinct transactivation regions rich in tyrosines, which are essential for transactivation. Our results thus show that the activity of the novel transactivating region of TR beta 2 is dependent on the organization of the half-sites in the response element.

Complications of intrathecal opioids and bupivacaine in the treatment of "refractory" cancer pain

OBJECTIVE

To test the concept that externalized tunneled intrathecal catheters lead to a high risk of complications, such as meningitis and epidural abscess, and therefore should not be used for durations of intrathecal pain treatment of > 1 week.

DESIGN

Prospective, cohort, nonrandomized, consecutive, historical control trial.

SETTING

Tertiary care center, institutional practice, hospitalized and ambulatory care.

PATIENTS

Two hundred adults (107 women, 93 men) with refractory cancer pain treated for 1-575 (median, 33; total, 14,485) days; 79 patients were treated at home for 2-226 (median, 36; total, 4,711) days. All patients had died by the close of the study.

INTERVENTIONS

Insertion of intrathecal tunneled nylon (Portex) catheters (223 in 200 patients) with Millipore filters. The catheter hubs were securely fixed to the skin with steel sutures. Standardized care after insertion: (a) daily phone contact with the patients, their families, or the nurses in charge; (b) weekly dressing change at the tunnel outlet by the nurses; (c) refilling of the infusion containers by the nurses; (d) exchange of the infusion systems when empty (within 1 month) and of the antibacterial filter once a month by specially instructed Pain Department nurses. All contact between the connections of the syringes, cassettes, and needles with the operator's hands was carefully avoided during filling and refilling of the infusion containers and exchange of the antibacterial filters; no other aseptic precautions were taken.

MAIN OUTCOME MEASURES

We recorded the rates of perfect function and complications of the systems. The rates of complications recorded in this study with externalized tunneled intrathecal catheters are discussed and compared with the rates reported in the literature with externalized (tunneled and non-tunneled) epidural and intrathecal catheters, as well as with internalized (both epidural and intrathecal) catheters connected to subcutaneous ports, reservoirs, and pumps.

RESULTS

The following rates (as a percentage of number of patients) of perfect function and complications of the systems were recorded (the ranges of rates reported in the literature are given in parentheses): perfect function of the system, 93% (31-90%); accidental injury of an unknown epidural tumor followed by an epidural hematoma, 0.5% (0-6%); skin breakdown at the insertion site, 2% (2-50%); postdural puncture headache, 15.5% (10%); external leakage of CSF, 3.5% (4-27%); CSF hygroma ("pseudomeningocele"), 1.5% (4-6.25%); hearing loss and Ménière-like syndrome, 0% (12%); pain on injection, 0% with continuous infusion and 4.5% with intermittent injections (3-36% with intermittent injections); catheter tip dislodgement, 1.5% (6-33%); catheter (system) occlusion, 1% (3-12%); accidental catheter withdrawal, 4% (3-22%); catheter (system) leakage, 1.5% (2.1-26.6%); all mechanical complications, 8.5% (10-44%); local (catheter entry site) infection, 0.5% (2-33%); catheter track infection, 0% (6-25%); epidural abscess, 0% (0.6-25%); meningitis, 0.5% (1-25%); systemic infection, 0% (3%); incidence of all infections (n/treatment days), 1/7,242 (1/168-1/2,446).

CONCLUSIONS

In our population and with the technique of insertion and care reported here, the use of externalized tunneled intrathecal catheters has not been associated with higher rates of complications when compared with earlier reported rates of externalized epidural catheters and internalized (both epidural and intrathecal) catheters connected to subcutaneously implanted ports, reservoirs, and pumps. The opinion that the use of externalized tunneled intrathecal catheters should be restricted only to patients who need pain treatment for < 1 week (because of the potential risk of infection, particularly meningitis and epidural abscess) is unfounded.

Visualization of fusion activation in the Semliki Forest virus spike

BACKGROUND

Viral spike proteins such as those of Semliki Forest virus (SFV) undergo a conformational change triggered by low pH which results in the fusion of the viral envelope with cellular membranes. The viral spike precursor of SFV is insensitive to low pH, and hence is fusion incompetent, until it is proteolytically cleaved to give the fusion competent mature form.

RESULTS

Three-dimensional image reconstructions from cryo-electron micrographs were used to compare the virion structure of wild-type SFV with that of a mutant SFV in which cleavage of the spike precursor had been blocked. Upon maturation to the fusion competent form, the spike undergoes a conformational change in which copies of the polypeptide containing the fusion sequence (E1) move from peripheral to lateral positions bringing them closer together.

CONCLUSIONS

This first visualization of the maturation of a viral spike protein complex suggests a mechanism for the conformational change which controls the fusion process.

Long-term intrathecal morphine and bupivacaine in patients with refractory cancer pain. Results from a morphine:bupivacaine dose regimen of 0.5:4.75 mg/ml

BACKGROUND

There are no clinical data regarding the ratios and concentrations in which morphine and bupivacaine should be combined, when given intrathecally, to improve analgesia while decreasing adverse effects. This study was undertaken to test the clinical efficacy of a constant infusion of 0.5 mg/ml morphine plus 4.75 mg/ml bupivacaine (morphine: bupivacaine approximately 1:10), given through open intrathecal catheters.

METHODS

In 53 patients, the clinical efficacy was estimated from: pain relief (visual analog scale scores 0-10); daily dosages (intrathecal and total opioid and intrathecal bupivacaine); scores (0-5) of nonopioid analgesic and sedative consumption, gait and daily activity, and amount of sleep; and rates of adverse effects.

RESULTS

During the intrathecal period (7-334, median 29 days), all 53 patients obtained acceptable pain relief (visual analog scale scores 0-2 vs. 6-10 in the pre-intrathecal stage). The total opioid daily consumption decreased (median 10 vs. 120 mg), the sleep was about two times longer, the nonopioid analgesic and sedative consumption about two times lower, and the gait ability pattern was unchanged. The daily dose of intrathecal morphine (median 6 mg) and the daily intrathecal volumes (median 10 ml) were low, whereas the daily dose of intrathecal bupivacaine was relatively high (median 50 mg). Side effects potentially related to intrathecal morphine (seizures, cerebral, and spinal clonus) were not recorded. Side effects attributable to intrathecal bupivacaine (in patients not having these complications before the intrathecal treatment) occurred in the forms of late urinary retention (9 of 27), paresthesias (11 of 27), paresis/gait impairment (9 of 27), and occasional episodes of orthostatic arterial hypotension (1 of 53 patients).

CONCLUSIONS

A constant intrathecal infusion with a morphine:bupivacaine ratio of approximately 1:10 and concentrations of morphine of 0.5 mg/ml and bupivacaine of 4.75 mg/ml may significantly improve the relief of refractory cancer pain with a certain risk of adverse effects (which should be balanced against pain by the patient) from the relatively high intrathecal bupivacaine doses and concentration.

Semliki Forest virus expression system: production of conditionally infectious recombinant particles

In the recently developed Semliki Forest virus (SFV) DNA expression system, recombinant RNA encoding the viral replicase, and helper RNA molecules encoding the structural proteins needed for virus assembly are cotransfected into cells. Since the helper RNA lacks the sequence needed for its packaging into nucleocapsids, only recombinant RNAs should be packaged. We have found, however, that small amounts of replication-proficient SFV particles can still be produced. Here we describe the construction of a helper variant with a mutation in the gene encoding the viral spike protein such that its product cannot undergo normal proteolytic processing to activate viral entry functions. Hence, the recombinant stock is noninfectious, but may be activated by cleavage with chymotrypsin. When recombinant virus produced with the new helper was examined in a variety of assays, including sensitive animal tests, we were unable to detect any replication-competent SFV particles. We therefore conclude that this conditional expression system meets extremely stringent biosafety requirements.

Binding characteristics of the thyroid hormone receptor homo- and heterodimers to consensus AGGTCA repeat motifs

Previous studies have shown that thyroid hormone receptors can form homo- and heterodimeric complexes when binding to response elements. We report here the binding characteristics of thyroid hormone receptor (TR) homo- and heterodimers binding to synthetic oligonucleotides with directly and palindromically repeated consensus motifs (AGGTCA). Binding assays showed that TR homodimer formation on DNA had a low specificity and cooperativity, and very fast off rates. In contrast, TRs and retinoic acid receptors readily formed heterodimers with higher specificity and affinity on direct repeats of the AGGTCA motif spaced by four or five nucleotides, although these heterodimer/DNA complexes were only moderately stable when compared to DNA-bound TR/retinoid X receptor heterodimers. Also, TR/retinoic acid receptor heteromeric binding to other elements, including the synthetic T3RE-pal element, was of low specificity. These biochemical results suggest that TRs are unlikely to regulate transcription as homodimers in vivo, and that TR heterodimers mediate the effects of thyroid hormone.

Neuropathologic findings after long-term intrathecal infusion of morphine and bupivacaine for pain treatment in cancer patients

Epidural or intrathecal infusions of morphine and bupivacaine mixtures are presently used for the treatment of "refractory" cancer pain even though the neurotoxic potential of such mixtures is unknown. The pathologic findings of the spinal column, the meninges, the nerve roots, and the spinal cord, and the clinical neurologic deficits were recorded in 15 patients (5 men and 10 women), aged 26-83 (median 68) yr, treated for 4-274 (median 81) days with intrathecal infusions of morphine (with preservatives [sodium metabisulfite and sodium edetate]) and bupivacaine mixtures, given through open, subcutaneously tunneled nylon catheters. Six patients had been subjected to radiation therapy (20-96 Gy), applied over the spinal column, and four had been treated with antineoplastics believed to be neurotoxic. Ten patients had various neurologic deficits before the intrathecal treatment. The cumulative doses (ranges) given intrathecally were: morphine 33-11,900 mg, sodium metabisulfite 3.3-1,050 mg, sodium edetate 0.33-105 mg, and bupivacaine 10-41,400 mg; cumulative volumes were 16-9,400 ml. The concentrations of the drugs in the mixtures were: morphine 0.25-4.0 mg/ml, sodium metabisulfite 0.025-0.40 mg/ml, sodium edetate 0.0025-0.04 mg/ml, and bupivacaine 3.0-4.75 mg/ml. The osmolality of the mixtures in vitro ranged from 282 to 286 mOsm/kg and the pH from 4.1 to 4.6. The pathologic findings consisted of vertebral metastases (n = 6), epidural and/or intrathecal tumor masses (n = 8), focal subdural fibrosis (n = 6), infiltration of mononuclear cells in the subarachnoid space (n = 10), and discrete injuries (nerve fiber degeneration or fibrosis) to the anterior (five patients) and posterior (seven) nerve roots, and spinal cord (tumor compression [one], slight thickening of the leptomeninges [one], and thrombosis of a spinal artery and medullary infarction [one]). In none of the cases was any reaction against the nylon catheter within its subarachnoid course recorded. The neuropathologic findings were not related to the duration or cumulative doses of the intrathecal treatment. No new neurologic deficits that could be attributed to the intrathecal administration of the opiate-bupivacaine mixtures were recorded. The neuropathologic and clinical neurologic findings in cancer patients treated with intrathecal morphine-bupivacaine mixtures appeared similar to those in animals and humans reported with either intrathecal morphine or bupivacaine alone.

Thyroid hormone receptors in chick retinal development: differential expression of mRNAs for alpha and N-terminal variant beta receptors

Thyroid-hormone-dependent development of the neuroretina has principally been described in amphibia. Here, we show by in situ hybridisation that mRNAs coding for three distinct thyroid hormone receptors (TRs), TR alpha and two TR beta variants, are differentially expressed during chick retinal development. We isolated a cDNA for a novel N-terminal variant of chick TR beta (cTR beta 2) that is predominantly expressed in retinal development. Interestingly, in its N-terminal A/B domain cTR beta 2 is 70% homologous to the rat pituitary-specific TR beta 2. Expression of cTR beta 2 mRNA was high at embryonic day 6 (E6) in the retinal outer nuclear layer (ONL) and decreased to low levels at hatching. mRNA for the previously described chick beta receptor, cTR beta 0, was expressed at low levels in both the ONL and the inner nuclear layer (INL) after E10. In contrast, cTR alpha expression occurred in the ONL, INL and ganglion cell layer at intermediate and later stages. Finally, cTR beta 2 confers a stronger trans-activation of reporter gene transcription than cTR beta 0. The distinctive kinetics and localisation of TR alpha and beta gene expression suggest cell- and stage-specific functions for TRs, both individually and in combinations, in chick neuroretinal development.

Long-term, open catheterization of the spinal subarachnoid space for continuous infusion of narcotic and bupivacaine in patients with "refractory" cancer pain. A technique of catheterization and its problems and complications

The technique of long-term, open catheterization of the spinal subarachnoid space for infusion of analgesics in patients with refractory cancer pain is sparsely reported in the literature. We report on a technique using 18G Portex nylon catheters and 16G-17G Tuohy needles, and its problems and complications. One hundred fifty-seven catheters were inserted in 142 patients, in most of them (79%) under deep sedation and local anesthesia. Attempts were made to place the catheter tip as close to the painful segments as possible. The catheters were tunneled subcutaneously (87% of them paravertebrally, over the shoulder, and further parasternally to the third chondrocostal cartilage). The Luer connections of the catheters were fixed to the patients' skin with monofilament steel sutures of dimension 0 and connected to a bacterial filter. At the end of the procedure, 10 ml isotonic saline was injected intrathecally to prevent postspinal puncture headache. Absorbent and impermeable dressings were applied over the tunnel exit, catheter Luer connection and bacterial filter. Antibiotics were given on the day of insertion and 2 days thereafter. During the insertion procedure, the following problems and complications were encountered; two or more attempts before successful spinal-dural puncture (32%), accidental puncture of an extradural vessel (10%), difficult dural puncture (18%), absence of free dripping of cerebrospinal fluid (CSF) in spite of successful dural puncture (4%), blood-stained CSF (9%), radicular pain and paresthesiae (4%), difficult advancement of the catheter (6%), difficult tunneling (11%), and bleeding in the tunnel (0.7%).(ABSTRACT TRUNCATED AT 250 WORDS)

Intracellular modifications of rat alpha 1 inhibitor3. Formation of disulphides, internal thiolester and sulphation

alpha 1 Inhibitor3 (alpha 1I3) is a monomeric protease inhibitor of about 190 kDa which is secreted by rodent hepatocytes. We have studied intracellular modifications of this protein in [35]methionine-labelled rat hepatocytes by pulse/chase experiments followed by immunoprecipitation and gel electrophoresis under reducing and nonreducing conditions. Directly after the pulse, most of the unreduced alpha 1I3 migrated faster than the reduced form, indicating that disulphide bridges are formed during or shortly after synthesis yielding a compact structure. With increasing chase time however, an increasing portion of the unreduced alpha 1I3 migrated with a mobility lower than that of the reduced protein, half-maximal conversion occurring after about 10 min. This finding suggests that alpha 1I3 undergoes a conformational change in the endoplasmic reticulum, possibly becoming more elongated. During 10-30 min of chase, the protein acquired the capacity to undergo autolytic cleavage upon heating, a property due to the existence of an internal thiolester bond [Howard, J. B., Vermeulen, M. & Swenson, R. P. (1980) J. Biol. Chem. 255, 3820-3823; Esnard, F., Gutman, N., El Moujahed, A. & Gauthier, F. (1985) FEBS Lett. 182, 125-129]. Analysis by subcellular fractionation indicated that this bond is formed in the endoplasmic reticulum. Finally, we show that secreted alpha 1I3 is sulphated, presumably at Tyr618.

Long-term intrathecal morphine and bupivacaine in "refractory" cancer pain. I. Results from the first series of 52 patients

Neither epidural (EDA) or intrathecal (IT) morphine nor EDA opiate + bupivacaine provides acceptable relief of some types of cancer pain, e.g. pain originating from mucocutaneous ulcers, deafferentation pain, continuous and intermittent visceral and ischaemic pain, and that occurring with body movement as a result of a fracture. To improve pain relief in such conditions, we gave combinations of morphine and bupivacaine through open IT-catheters to 52 patients with "refractory", severe (VAS 7-10 out of 10), complex cancer pain (Edmonton Stage-3), for periods of 1-305 (median = 23) days. The efficacy of the treatment was estimated from: 1) daily dosage (intraspinal and total opiates, and intraspinal bupivacaine), and 2) scores of non-opiate analgesic and sedative consumption, gait and daily activities, and amount and pattern of sleep. Forty-four patients obtained continuous and acceptable pain relief (VAS 0-2), 26 of them with daily doses of IT-bupivacaine of less than or equal to 30 mg/day (less than or equal to 1.5 mg/h). Higher IT-bupivacaine doses (greater than 60-305 mg/day), not always giving acceptable pain relief, were necessary in 13 patients with deafferentation pain from the spinal cord or brachial or lumbosacral plexuses or pain from the coeliac plexus, or from large, ulcerated mucocutaneous tumours. By combining IT-bupivacaine with IT-morphine, it was possible to use relatively low IT-morphine doses (10-25 mg/day during the first 2 months of treatment) in more than half of the patients. The IT-treatment significantly decreased the total (all routes) opiate consumption and significantly improved sleep, gait and daily activities. For the whole period of observation (6 months), the IT-treatment was assessed as adequate in 3.8%, good in 23.1%, very good in 59.6% and excellent in 13.5% of the cases. Adverse effects of the IT-bupivacaine (paraesthesiae, paresis, gait impairment, urinary retention, anal sphincter disturbances and orthostatic hypotension) did not occur with doses of 2.5-3.0 mg/h (approx. 60-70 mg/day).

Contrasting developmental and tissue-specific expression of alpha and beta thyroid hormone receptor genes

Thyroid hormones and their receptors (TRs) have critical functions in development. Here we show that a chicken TR beta cDNA clone encodes a receptor with a novel, short N-terminal domain. In vitro-expressed TR beta protein bound thyroid hormone with similar affinity as the chicken TR alpha. Comparison of expression of TR alpha and TR beta mRNAs throughout chicken development until 3 weeks post-hatching revealed ubiquitous expression of TR alpha mRNAs (in 14 different tissues) with some variations in levels, from early embryonic stages. In contast, expression of TR beta mRNA was restricted, occurring notably in brain, eye, lung, yolk sac and kidney, and was subject to striking developmental control, especially in brain where levels increased 30-fold upon hatching. Levels also sharply increased in late embryonic lung, but were relatively high earlier in embryonic eye and yolk sac. RNase protection analyses detected no obvious mRNAs for alpha and beta TRs with variant C-termini as demonstrated previously for the rat TR alpha gene. The data suggest a general role for TR alpha and specific developmental functions for TR beta, and that thyroid-dependent development involves temporal and tissue-specific expression of the TR beta gene.

Epidural versus intrathecal morphine-bupivacaine: assessment of consecutive treatments in advanced cancer pain

Twenty-five patients with multifocal and multitype (somatic, visceral, and neurogenic) advanced cancer pain who experienced severe pain despite extradural (ED) morphine and bupivacaine were converted to intrathecal (IT) morphine and bupivacaine. The consecutive ED and IT periods (2-174 days, median = 50 days, and 1-305 days, median = 37 days, respectively) were assessed in clinical terms (daily analgesic dosages giving acceptable pain relief and quality of life expressed as sleeping hours and walking/daily activities). With the IT treatment, the total (all routes) opiate consumption and the daily doses of spinal morphine and spinal bupivacaine decreased significantly at the beginning of the treatment compared to the ED period, and continued to be significantly reduced for up to 1 wk for spinal opiate and bupivacaine and 6 mo for total opiate. The spinal opiate and bupivacaine doses were still lower in 50% of the patients at the end of the IT treatment compared to the end of the ED period. When final ED versus initial (2nd day) IT doses were assessed, the daily median dose ratios were 7.5 for total opiate and 4 for both spinal opiate and bupivacaine. Subsequently, lower daily volumes and higher concentrations were needed for IT administration of the drugs. During the first month of the IT treatment, sleeping and walking scores improved compared to ED treatment. Thus, the IT treatment gave more satisfactory pain relief, and--because of lower daily doses and volume--proved to be more suitable for treatment at home (continuous infusion from external pumps) than the ED treatment.