Higher Preimplantation Opioid Doses Associated With Long‐Term Spinal Cord Stimulation Failure in 211 Patients With Failed Back Surgery Syndrome

ObjectiveSpinal cord stimulation (SCS) is an effective treatment in failed back surgery syndrome (FBSS). We studied the effect of preimplantation opioid use on SCS outcome and the effect of SCS on opioid use during a two-year follow-up period.Materials and methodsThe study cohort included 211 consecutive FBSS patients who underwent an SCS trial from January 1997 to March 2014. Participants were divided into groups, which were as follows: 1) SCS trial only (n = 47), 2) successful SCS (implanted and in use throughout the two-year follow-up period, n = 131), and 3) unsuccessful SCS (implanted but later explanted or revised due to inadequate pain relief, n = 29). Patients who underwent explantation for other reasons (n = 4) were excluded. Opioid purchase data from January 1995 to March 2016 were retrieved from national registries.ResultsHigher preimplantation opioid doses associated with unsuccessful SCS (ROC: AUC = 0.66, p = 0.009), with 35 morphine milligram equivalents (MME)/day as the optimal cutoff value. All opioids were discontinued in 23% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.004). Strong opioids were discontinued in 39% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.04). Mean opioid dose escalated from 18 ± 4 MME/day to 36 ± 6 MME/day with successful SCS and from 22 ± 8 MME/day to 82 ± 21 MME/day with unsuccessful SCS (p < 0.001).ConclusionsHigher preimplantation opioid doses were associated with SCS failure, suggesting the need for opioid tapering before implantation. With continuous SCS therapy and no explantation or revision due to inadequate pain relief, 39% of FBSS patients discontinued strong opioids, and 23% discontinued all opioids. This indicates that SCS should be considered before detrimental dose escalation.     

Angiographic vasospasm and release of platelet thromboxane after subarachnoid hemorrhage

We studied adenosine diphosphate-induced platelet aggregation and the associated release of thromboxane B2 in 49 patients with subarachnoid hemorrhage in relation to angiographic vasospasm. Postoperative cerebral angiography was performed less than or equal to 3 (median 1) days after surgery for an aneurysm 5-14 days after subarachnoid hemorrhage. Correspondingly, one sample from each patient was taken within 24 hours either before or after angiography. The occurrence of severe as well as diffuse, moderate, or severe angiographic vasospasm was associated with the presence of delayed cerebral ischemia (p less than 0.05). Patients with diffuse angiographic vasospasm had significantly higher (p less than 0.05) values for thromboxane B2 release than the others, even after adjustment by the clinical grades on admission and before surgery, the timing of surgery, the time from subarachnoid hemorrhage to angiography and blood sampling, and nimodipine therapy. Severe and diffuse angiographic vasospasm were also associated with poor outcome at 1 year (p less than 0.05). Our results suggest that augmented release of platelet thromboxane may be involved in the pathogenesis of vasospasm in large cerebral arteries.     

Altered enzyme activities of xenobiotic biotransformation in kidneys after subchronic administration of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) to rats

Activities of the xenobiotic metabolizing enzymes were measured in the liver, kidney, duodenum and lung microsomes and cytosol fractions of Wistar rats after subchronic administration of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a potent bacterial mutagen in chlorinated drinking water. MX was administered by gavage at the dose level of 30 mg/kg for 18 weeks (low dose), or at the dose level which was raised gradually from 45 mg/kg for 7 weeks via 60 mg/kg for 2 weeks to a clearly toxic dose of 75 mg/kg for 5 weeks (high dose). Microsomal and cytosolic preparations were made and the activities of 7-ethoxyresorufin-O-deethylase (EROD), pentoxyresorufin-O-dealkylase (PROD), NADPH-cytochrome-c-reductase, UDP-glucuronosyltransferase (UDPGT) and glutathione-S-transferase (GST) were measured. Kidneys were affected most. A dose-dependent decrease was observed in EROD (90% in males, 80% in females at the high dose) and in PROD (58% in females, at the high dose) in kidneys. An increase was, however, detected in kidney NADPH-cytochrome-c-reductase (66% in females at high dose), UDPGT (89% in males and 97% in females at high dose) and GST activities (56% in males and 50% in females at high dose). MX caused only a few changes in the enzyme activities of the liver. The EROD activity was decreased 25% to 37%, both in the livers of males and females, but the total content of P450s was not altered. Hepatic GST activity was elevated in females in a dose-dependent manner (31% and 44%). GST activity was elevated in duodenum in females (59%) at the high dose. There were no marked changes in the enzyme activities in the lungs. MX was a weak inhibitor of EROD activity both in the liver and kidney microsomes in vitro, decreasing the EROD activity by 53% and 43%, respectively at the concentration of 0.9 mM. The results indicate that MX decreases the activity of phase I metabolism enzymes, but induces phase II conjugation enzyme activities, particularly in kidneys in vivo. It is possible that these changes contribute to metabolism of MX in kidneys and renders them susceptible to MX in the course of repeated exposure.     

Effect of linoleic acid, linoleic acid anilide, and arachidonic acid on the expression of adhesion molecules on human neutrophils

The effects of linoleic acid, linoleic acid anilide, and arachidonic acid on the expression of CD11b/CD18, CD11c/CD18 integrins and l-selectin on human neutrophils were studied by flow cytometry in a whole blood assay. None of these compounds had any effect on the basal expression of CD11b, CD11c, or l-selectin in the concentration range of 20–100 μM. However, linoleic acid at a concentration of 1000 μM slightly up-regulated CD11b and CD11c by a factor of 2.1 and 1.7, respectively. Linoleic acid, linoleic acid anilide, and arachidonic acid did not affect the formyl-methionyl-leucyl-phenylalanine induced up-regulation of CD11b or CD11c. However, linoleic acid and linoleic acid anilide slightly inhibited the phorbol myristate acetate (PMA)-induced expression of CD11b, which was decreased by 27 and 21% at concentrations of 100 and 1000 μM, respectively. Likewise, arachidonic acid at 40 μM inhibited the PMA-induced expression of CD11b by 19%. Our results suggest that linoleic acid, linoleic acid anilide, and arachidonic acid do not dramatically affect the expression of leukocyte adhesion molecules in a whole blood assay. Received: 17 February 1997  / Accepted: 5 May 1997     

A peptide inhibitor of vascular adhesion protein-1 (VAP-1) blocks leukocyte-endothelium interactions under shear stress

Vascular adhesion protein-1 (VAP-1) is an endothelial adhesion molecule mediating leukocyte interactions with blood vessels during leukocyte extravasation. Molecularly VAP-1 is a cell-surface-expressed ecto-enzyme belonging to the group of semicarbazide-sensitive amine oxidases (SSAO; EC 2.4.6.3), which deaminate primary amines. Here we asked whether peptides displaying a suitable free amine group could be a substrate or inhibitor of SSAO and thus regulate VAP-1-mediated leukocyte adhesion. On the basis of a molecular model of VAP-1, we designed synthetic peptides that fit to the substrate channel of VAP-1. One of these lysine-containing peptides effectively inhibits VAP-1-dependent lymphocyte rolling and firm adhesion to primary endothelial cells under physiologically relevant shear conditions. The same peptide inhibits the SSAO activity of endothelial and recombinant VAP-1 in a selective and long-lasting manner. We also show that all enzymatically active VAP-1 is displayed on the cell surface. Our results suggest that, in addition to soluble amines, specific cell-surface-bound molecules containing free NH(2) groups in a suitable position may modulate the enzymatic activity of SSAO. Moreover, the inhibitory peptide diminishes leukocyte interactions with endothelial cells under conditions of shear, and thus it may be useful to treat inflammatory conditions.     

CDK4 is a probable target gene in a novel amplicon at 12q13.3-q14.1 in lung cancer

Several chromosomal regions are recurrently amplified or deleted in lung tumors, but little is known about the underlying genes, which could be important mediators in tumor formation or progression. In lung cancer, the RB1-CCND1-CDKN2A pathway, involved in the G1-S transition, is damaged in nearly all tumors. In the present study, we localized a novel amplicon in lung tumors to a fragment of less than 0.5 Mb at 12q13.3-q14.1 by using comparative genomic hybridization (CGH) on cDNA microarrays. This approach enabled us to identify 10-15 genes with the most consistent amplifications. Semiquantitative RT-PCR analyses of 13 genes in this region showed that four of them (CDK4, CYP27B1, METTL1, and TSFM) were also highly up-regulated. Immunohistochemical (IHC) analysis of 141 tumor samples on a tissue microarray showed that CDK4 was expressed at a high level in 23% of lung tumors. Six (21.4%) of the tumors with high CDK4 expression (n = 28) were shown by fluorescence in situ hybridization (FISH) to contain the 12q13.3-q14.1 amplification. For CDK4, a positive correlation was found between gene copy number (FISH and CGH array), mRNA expression (RT-PCR), and level of protein expression (IHC). CDK4 expression did not correlate with CDKN2A methylation status. Amplification of CDK4 has been described in other tumor types, but its role in lung cancer remains to be elucidated. Although CDK4 amplification seems to be a relatively rare event (4.3%) in lung tumors, it indicates the significance of the RB1-CCND1 pathway in lung tumorigenesis.     

Molecular epidemiology of two international sprout-borne Salmonella outbreaks.

Sprout-borne Salmonella outbreaks in Finland have increased during the last 10 years. The latest two were caused by Salmonella enterica serovar Bovismorbificans (antigenic structure 6,8:r:1,5) in 1994 and S. enterica serovar Stanley (4,5, 12:d:1,2) in 1995. In this study, the restriction fragment length polymorphism of genomic DNA after pulsed-field gel electrophoresis (PFGE) and antimicrobial resistance profiles of the outbreak and nonoutbreak strains were compared. In each separate outbreak, the PFGE patterns of the outbreak strains (40 strains of S. enterica serovar Bovismorbificans and 28 strains of S. enterica serovar Stanley) after digestion of genomic DNA with restriction enzyme XbaI were indistinguishable from each other but differed clearly from those of the nonoutbreak strains (26 strains of S. enterica serovar Bovismorbificans and 40 strains of S. enterica serovar Stanley). The restriction enzyme XhoI did not differentiate the outbreak and nonoutbreak strains. The S. enterica serovar Stanley strains associated with the outbreak also had a unique antimicrobial resistance pattern, whereas all S. enterica serovar Bovismorbificans strains, both outbreak and nonoutbreak strains, were sensitive to all antimicrobial agents tested. Thus, the molecular typing confirmed that the S. enterica serovar Bovismorbificans outbreak isolates from humans and sprout salad were identical and strongly supported the epidemiological finding that S. enterica serovar Stanley outbreak isolates also originated from contaminated alfalfa seeds. It also confirmed that the sources of similar outbreaks in Sweden in 1994 caused by S. enterica serovar Bovismorbificans and in the United States in 1995 caused by S. enterica serovar Stanley and the source of the Finnish outbreaks were common.     

Timing of different virus neutralizing 19S and 7S antibodies in natural Coxsackie infections of newborn babies and adults

Neutralizing Coxsackie antibodies arising from natural infections with Coxsackie virus type B3 or B5 were studied in adults and newborn babies. No differences could be found between the antibody response of the newborn babies and that of the adults.

The antibody titres rose approximately as rapidly in the babies as in the adult patients, and the means of the peak titres did not differ significantly in the two groups. Early in the infection the neutralizing antibodies of both newborn babies and adults were exclusively IgM. There was a gradual shift to IgG in the course of 3 months, and this shift was as rapid in babies as in adults.

     

p53Mutations and Presence of HPV DNA Do Not Correlate with Radiosensitivity of Gynecological Cancer Cell Lines

Objective.The correlation betweenp53tumor suppressor gene mutations and the presence of high-risk human papillomavirus (HPV) DNA with thein vitroradiosensitivity of gynecological malignancies was studied in 26 cell lines derived from gynecological cancers of 23 patients.Methods.Comparison of the intrinsic radiosensitivity was performed with mean inactivation dose (D?) determined with the 96-well plate clonogenic assay.p53mutations were investigated with polymerase chain reaction and single-strand conformation polymorphism (PCR–SSCP) analysis and direct DNA sequencing, and the presence of HPV DNA was studied with PCR using HPV consensus primers.Results. p53mutations were found in 6 of 10 vulvar squamous cell carcinoma (SCC) lines. Nine vulvar and 1 vaginal SCC cell lines were HPV DNA negative and 1 vulvar cell line was HPV 16 positive. All 4 cervical SCC lines were HPV positive and possessed the wild-typep53.Three cell lines expressed HPV 16 and 1 HPV 68. Among 10 endometrial cancer cell lines, 2 cell lines with mutantp53and 1 HPV 16 positive cell line were found. No correlation could be demonstrated between inactivation of thep53gene and radiosensitivityin vitro;the cell lines were evaluated as one group or according to their anatomical origin or histology.Conclusion.Our results indicate that inactivation of thep53gene through mutation or binding with HPV DNA does not increase the resistance of gynecological malignancies to ionizing radiationin vitro.