Campylobacter jejuni-stimulated secretion of interleukin-8 by INT407 cells

STUDY OBJECTIVES: To examine the effect of three titration schedules on the tolerability of tramadol, and to determine whether slow titration would reduce the frequency of drug discontinuation due to adverse events. DESIGN: Multicenter, outpatient, double-blind, parallel study. SETTING: Twenty-eight outpatient study centers. SUBJECTS: Four hundred sixty-five patients with chronic joint pain Interventions. Patients were randomized into one of four treatment groups for 14 days: placebo, or tramadol dosage titrated at 1, 4, or 10 days to achieve the study target dosage of 200 mg/day. They continued taking their dosage of nonsteroidal antiinflammatory drug during the study. Each group was examined to determine if slower titration resulted in a statistically significant trend toward fewer discontinuations due to nausea and/or vomiting and dizziness and/or vertigo. Discontinuation due to any adverse event was similarly analyzed. If the trend was statistically significant, pairwise comparisons were performed to determine the statistical significance among titration rates. MEASUREMENTS AND MAIN RESULTS: A statistically significant trend was seen toward fewer discontinuations as a result of nausea/vomiting, dizziness/vertigo, and any adverse event as the titration rate decreased. Patients with 10-day titration rate required the fewest discontinuations, and this rate was statistically significantly different from both the 1- and 4-day rates for discontinuations. CONCLUSION: A slower rate of initiating tramadol therapy (50-mg increments every 3 days) improved tolerability with significantly fewer discontinuations due to dizziness or vertigo.     

Theophylline for irreversible chronic airflow limitation: a randomized study comparing n of 1 trials to standard practice

Antibody-directed enzyme prodrug therapy (ADEPT) is a technique to increase antitumor selectivity in cancer chemotherapy. Our approach to this technology has been to design a mutant of human carboxypeptidase A (hCPA1-T268G) which is capable of hydrolyzing in vivo stable prodrugs of MTX and targeting this enzyme to tumors on an Ep-CAM1-specific antibody, ING1. Through the use of this >99% human enzyme which is capable of catalyzing a completely nonhuman reaction, we hope to increase ADEPT selectivity while decreasing overall immunogenicity of the enzyme-antibody conjugate. In the current report, prodrugs of the thymidylate synthase inhibitors GW1031 and GW1843 and the dihydrofolate reductase inhibitor methotrexate were studied for their wild-type and mutant hCPA enzyme hydrolysis, their in vivo stability, and their use in therapy. Prodrugs with high kcat/Km ratios for mutated versus wild-type hCPA1 were examined in vitro for their stability in human pancreatic juice, and in vivo for their stability in mouse plasma and tissues. In addition, targeting and in vivo enzyme activity studies were performed with an ING1 antibody conjugate of the mutant enzyme (ING1-hCPA1-T268G). Finally, in vivo therapy studies were performed with LS174T tumors to demonstrate proof of principle. Results indicate that prodrugs can be synthesized that are selective and efficient substrates of hCPA1-T268G and not substrates of the endogenous CPA activities; this leads to excellent in vivo stability for these compounds. In vivo conjugate targeting studies showed that the antibody-enzyme conjugate was targeted to the tumor and enzyme was initially active in vivo at the site. Unfortunately therapeutic studies did not demonstrate tumor reduction. Experiments to determine reasons for the lack of antitumor activity showed that the enzyme activity decreased as a result of enzyme instability. The results offer encouragement for additional novel mutant enzyme improvements and additional in vivo studies on this unique approach to ADEPT.     

Ordered mesoporous polymers of tunable pore size from colloidal silica templates

Ordered mesoporous polymers have been prepared by replication of colloidal crystals made from silica spheres 35 nanometers in diameter. The pores in the colloidal crystals were filled with divinylbenzene (DVB), ethyleneglycol dimethacrylate (EDMA), or a mixture of the two. Polymerization and subsequent dissolution of the silica template leaves a polycrystalline network of interconnected pores. When mixtures of DVB and EDMA are used, the pore size of the polymer replicas can be varied continuously between 35 and 15 nanometers because the polymer shrinks when the silica template is removed.     

Risk factors for progression to new sites of radiographically defined osteoarthritis in women

OBJECTIVE: To describe the association between hormonally related risk factors and the progression to new sites of radiographically defined full body (generalized) osteoarthritis (OA) in a cohort of older women. METHODS: A retrospective cohort design was used to study former radium dial painters over the age of 40 years who had minimal radium exposure. At study entry and at varying followup times, clinical examinations were conducted and full body radiographs were taken. Two followup groups were defined: women with a followup radiograph 1-9 years after baseline (n = 75) and 10-19 years after baseline (n = 53). Fifty-five joints (10 joint groups) were independently graded at baseline and followup for OA by the method of Kellgren and Lawrence, and provided the basis for summary full body OA progression scores. Progression was defined as an increase in the number of sites with OA and in separate analyses as an increase in the number of joint groups with OA. RESULTS: Increasing length of followup and lower baseline OA score were associated with greater OA progression, while age at baseline examination showed no clear relation to progression. Beyond these variables, increasing height and having ever smoked were inversely associated with OA progression, while body mass index (BMI) showed a weak positive association. In multivariable modeling for followup 1-9 years, only lower baseline OA score predicted greater OA progression to new sites (partial r2 = 0.13, p = 0.0009). In followup 10-19 years, baseline OA score (partial r2 = 0.12, p = 0.0011), height (partial r2 = 0.057, p = 0.033), and smoking status (partial r2 = 0.09, p = 0.035) were independent predictors of OA progression to new sites, while greater BMI was a positive, weak, and nonsignificant predictor (partial r2 = 0.031, p = 0.29). History of prior cholecystectomy, hysterectomy, dilation and curetage, number of pregnancies, and change in BMI were not significantly related to progression of OA to new sites. Similar results were found for predictors of OA progression to new joint groups. CONCLUSION: Lower baseline level of OA is associated with greater OA progression to new sites or joint groups independent of age, suggesting a "burnout" phenomenon. In addition, shorter height and having never smoked appear to be independent risk factors that predict the progression of radiographic OA to new sites or joint groups.     

Nitric oxide precursor arginine and S-nitrosoglutathione in synaptic and glial function

In the last few years, there has been an important increase in interest in nitric oxide (NO) as an intercellular messenger, and its putative role in numerous CNS functions is being continually updated. Arginine, the nitric oxide precursor, has been found in our laboratory to be released following stimulation of the white matter in the cerebellum and of sensory afferents in the thalamus. Since arginine is localized in glial cells while the nitric oxide synthesizing enzyme is localized in different cells (predominantly in neurons), these findings may represent a transfer of arginine from glia to neurons in order to supply the nitric oxide synthase with its substrate. The mechanism underlying this glial-neuronal interaction seems to involve the activation of excitatory amino acid receptors present on glial cells. Our results speak for an intense crosstalk between neurons and glia (activation of glial receptors by neurotransmitter released from neurons) and between glia and neurons (supply of the nitric precursor arginine from glia to neurons). The form in which NO is released from cells has been much debated. The chemical identity of the endothelial-derived relaxing factor in particular is still a matter of dispute, the major contender being NO. and a S-nitrosothiol compound. Based on the strong reactivity of NO for thiols and on the presence of cysteine and glutathione at the mM level intracellularly and microM level extracellularly, we have investigated whether S-nitrosothiols, i.e. S-nitrosoglutathione, may be the potential "package" form in which NO could be stored. We demonstrated, with HPLC coupled to mass spectrometry techniques, the presence of endogenous nitrosoglutathione in rat brain tissue. This packaging of NO in the form of nitrosothiols might serve to facilitate its transfer, prolong its life, and target its delivery to specific effectors. That could confer a specificity of action to the widely diffusable messenger NO, may determine the range of effectiveness of NO and mitigate its adverse cytotoxic effects.     

Non-union of the scaphoid. Treatment with cannulated screws compared with treatment with Herbert screws

We retrospectively reviewed the results for thirty-four patients in whom a non-union of the scaphoid had been treated with bone-grafting and internal fixation with use of one of two types of screws as well as the temporary placement of Kirschner wires parallel to the screw to prevent rotation. The patients were divided into two groups: Group 1 contained sixteen patients who had been managed with a Herbert screw from 1986 through 1989 and Group 2, eighteen patients who had been managed with a 3.5-millimeter cannulated AO/ASIF screw from 1990 through 1992. There were no clinical or radiographic differences between the two groups. The time to union, confirmed with tomography, was 7.6 +/- 3.6 months for Group 1 and 3.6 +/- 1.2 months for Group 2. This difference was significant (p < 0.01). Both screws significantly improved the alignment of the scaphoid and decreased carpal collapse (p < 0.05). Regardless of the type of screw used, the time to union was significantly shorter when the screw had been placed in the central one-third of the scaphoid (p < 0.05). Seventeen of the eighteen cannulated screws had been placed centrally, compared with seven of the sixteen Herbert screws (p < 0.01).     

Hepatitis B and C infection among drug abusers in Nepal

Prevalence of hepatitis B and C virus infection amongst intravenous drug users (IDU) in Nepal is not known. To estimate such prevalence 72 IDU individuals were tested for HBV and HCV markers. About 80% of the drug abusers are both anti-HBc (59/72) and anti-HCV (58/72) sero-positive. However persistent infection with hepatitis B, as indicated by positive HBsAg, was detected in only 5.5% (n = 4). Active hepatitis C infection, as indicated by HCV RNA positivity, was documented in 74% (42/58) of those who were anti-HCV positive. Importance of awareness of this observation among the healthcare workers in the prevention of hepatitis C in the community is stressed.     

Regulation of IL-6 synthesis in human peripheral blood mononuclear cells by C3a and C3a(desArg)

The anaphylatoxin C3a has been reported to have immunomodulatory effects on a number of different cell types. In this study we investigated the effects of C3a and C3a(desArg) on gene expression and protein secretion of IL-6 in human PBMCs, either alone or in combination with LPS or IL-1beta. C3a or C3a(desArg) alone exhibited no effect on the expression or secretion of IL-6. However, when PBMC were stimulated with LPS or IL-1beta, both C3a and C3a(desArg) were found to enhance IL-6 release by PBMC in a dose-dependent manner. Since C3a has been shown to induce PGE2 production by monocytes, and PGE2 has been shown to influence cytokine production, we investigated the potential role of PGE2 in C3a-mediated enhancement of LPS- and IL-1beta-induced IL-6 production. Indomethacin blocked PGE2 release, but had no influence on the observed effects of C3a, suggesting that the effects of C3a on IL-6 production are independent of PGE2 formation by monocytes. Northern blot analysis showed that C3a as well as C3a(desArg) enhanced LPS-induced mRNA levels for IL-6. Pretreatment of PBMCs with pertussis toxin blocked the functions of C3a and C3a(desArg), indicating that the actions of these two molecules are mediated by a G protein-coupled pathway. Furthermore, we investigated the effects of C3a and C3a(desArg) on induction of NF-kappaB and activating protein-1 binding. Both molecules enhanced LPS-induced NF-kappaB and activating protein-1 binding activity. These results demonstrate the capacity of intact C3a and its circulating des-Arg form to exert immunmodulatory effects in vitro.     

Interferons regulate the phenotype of wild-type and mutant herpes simplex viruses in vivo

Mechanisms responsible for neuroattenuation of herpes simplex virus (HSV) have been defined previously by studies of mutant viruses in cultured cells. The hypothesis that null mutations in host genes can override the attenuated phenotype of null mutations in certain viral genes was tested. Mutants such as those in infected cell protein (ICP) 0, thymidine kinase, ribonucleotide reductase, virion host shutoff, and ICP34.5 are reduced in their capacity to replicate in nondividing cells in culture and in vivo. The replication of these viruses was examined in eyes and trigeminal ganglia for 1-7 d after corneal inoculation in mice with null mutations (-/-) in interferon receptors (IFNR) for type I IFNs (IFN-alpha/betaR), type II IFN (IFN-gammaR), and both type I and type II IFNs (IFN-alpha/beta/gammaR). Viral titers in eyes and ganglia of IFN-gammaR-/- mice were not significantly different from congenic controls. However, in IFN-alpha/betaR-/- or IFN-alpha/beta/gammaR-/- mice, growth of all mutants, including those with significantly impaired growth in cell culture, was enhanced by up to 1,000-fold in eyes and trigeminal ganglia. Blepharitis and clinical signs of infection were evident in IFN-alpha/betaR-/- and IFN-alpha/beta/gammaR-/- but not control mice for all viruses. Also, IFNs were shown to significantly reduce productive infection of, and spread from intact, but not scarified, corneas. Particularly striking was restoration of near-normal trigeminal ganglion replication and neurovirulence of an ICP34.5 mutant in IFN-alpha/betaR-/- mice. These data show that IFNs play a major role in limiting mutant and wild-type HSV replication in the cornea and in the nervous system. In addition, the in vivo target of ICP34.5 may be host IFN responses. These experiments demonstrate an unsuspected role for host factors in defining the phenotypes of some HSV mutants in vivo. The phenotypes of mutant viruses therefore cannot be interpreted based solely upon studies in cell culture but must be considered carefully in the context of host factors that may define the in vivo phenotype.