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Notes: Abstract: The PNS was anticipated to be involved in the modulation of immune responses. To study aspects of this neuronal-immune communication, a recently developed tissue slice method was used to study the effects of adrenergic and opioidergic transmitters on interleukin 6 (IL-6) secretion in the spleen. The α2-adrenergic agonist p-aminoclonidine (10−7M) inhibited IL-6 secretion (control vs. p-aminoclonidine, 100.0 ± 4.76 vs. 59.3 ± 6.6% of control values; p 〈 0.001). The α1-adrenergic agonist methoxamine (10−8M) also inhibited IL-6 secretion (100.0 ± 4.8 vs. 71.5 ± 3.8%; p 〈 0.001). The endogenous opioids β-endorphin (10−10M), methionine-enkephalin (10−9M), and leucine-enkephalin (10−9M) inhibited IL-6 secretion as well (p = 0.0051, p = 0.0337, and p = 0.0226, respectively). Electrical stimulation of spleen slices inhibited IL-6 secretion (100.0 ± 4.3 vs. 56.7 ± 4.6% of control values; p 〈 0.001). The involvement of α-adrenergic and opioidergic molecules in this electrically induced inhibition was shown by the use of antagonists. Electrical inhibition of IL-6 secretion was attenuated by phentolamine (10−7M; p = 0.0345), by naloxone (10−6M; p = 0.0046), by cyprodime (10−8M; p = 0.0014), and by the combination of cyprodime (10−7M) plus phentolamine (10−8M; p 〈 0.0001). We conclude from the complementary studies that the inhibition of IL-6 secretion induced by electrical pulses was mostly mediated by α-adrenergic and μ-opioidergic endogenous transmitters.

Notes: Abstract: The CNS modulates immune cells by direct synaptic-likecontacts in the brain and at peripheral sites, such as lymphoid organs. Tostudy the nerve-macrophage communication, a superfusion method was used toinvestigate cotransmission of neuropeptide Y (NPY) with norepinephrine (NE),with interleukin (IL)-6 secretion used as the macrophage read-out parameter.Spleen tissue slices spontaneously released NE, NPY, and IL-6 leading to asuperfusate concentration at 3-4 h of 1 nM, 10 pM, and 120pg/ml, respectively. Under these conditions, NPY dose-dependently inhibitedIL-6 secretion with a maximum effect at 10-10M(p = 0.012) and 10-9M (p 〈 0.001).Simultaneous addition of NPY at 10-9M and theα-2-adrenergic agonist p-aminoclonidine further inhibited IL-6secretion (p 〈 0.05). However, simultaneous administration of NPYat 10-9M and the β-adrenergic agonist isoproterenolat 10-6M or NE at 10-6Msignificantly increased IL-6 secretion (p 〈 0.005). To objectifythese differential effects of NPY, electrical field stimulation of spleenslices was applied to release endogenous NPY and NE. Electrical fieldstimulation markedly reduced IL-6 secretion, which was attenuated by the NPYY1 receptor antagonist BIBP 3226 (10-7M, p = 0.039;10-8M, p = 0.035). This indicates that NPY increases theinhibitory effect of endogenous NE, which is mediated at low NE concentrationsvia α-adrenoceptors. Blockade of α-adrenoceptors attenuatedelectrically induced inhibition of IL-6 secretion (p 〈 0.001),which was dose-dependently abrogated by BIBP 3226. This indicates that underblockade of α-adrenoceptors endogenous NPY supports the stimulatingeffect of endogenous NE via β-adrenoceptors. These experimentsdemonstrate the ambiguity of NPY, which functions as a cotransmitter of NE inthe nerve-macrophage interplay.

Notes: Abstract. Tubulinosema ratisbonensis is a microsporidian pathogen of Drosophila melanogaster belonging to the family Tubulinosematidae. The microsporidia in this family mainly cause infections in invertebrate hosts, but two members of this family, Brachiola vesicularum and Brachiola algerae, have been found to cause infections in humans as well. Moreover, B. algerae can be transmitted to immunodeficient mice and grows in mammalian cell cultures. Thus, the examination of the opportunistic properties of other members of the family Tubulinosematidae is important. Spores of T. ratisbonensis, isolated from infected fruit flies, were used to inoculate mammalian and insect cell cultures. Parasite growth was only seen in human lung fibroblasts. No growth was seen in Vero cells or insect cell cultures. Comparison of growth kinetics at 31°C and 37°C showed that there were fewer and smaller parasitic foci in cultures incubated at 37°C. Transmission electron microscopy revealed the typical ultrastructure of T. ratisbonensis, and scanning electron microscopy showed oval or slightly pyriform spores, with some spores having extruded their polar tubes. The PCR-amplified sequences of rDNA fragments from infected cell cultures were 100% identical to the original T. ratisbonensis rRNA sequence. As T. ratisbonensis is able to proliferate in mammalian cell cultures, it may have the opportunistic properties of other members of the family Tubulinosematidae.

Notes: Abstract. A new species of microsporidia from Drosophila melanogaster was investigated by light and electron microscopy and by ribosomal RNA (rRNA) sequencing. This microsporidium and the previously described Nosema kingi and Nosema acridophagus have been transferred to the new genus Tubulinosema gen. nov. with the following characters: nuclei are in diplokaryotic arrangement during the life cycle. All stages are in direct contact with the host cell cytoplasm, slightly anisofilar polar tube with the last coils being smaller in diameter arranged in one or two rows on both sides of the diplokaryon and small tubuli on the surface of late meronts. Spores are oval or slightly pyriform. Thick endospore wall, thinner over anchoring disc. This new genus and the genus Brachiola have been placed in a new family Tubulinosematidae fam. nov. Phylogenetic analysis of small subunit rRNA sequences by different methods placed Tubulinosema spp. in one clade with the genus Brachiola forming its sister clade, which is distant from the clade containing the true Nosema spp. including Nosema bombycis.

Notes: Background : 6-Thioguanine-nucleotides seem to be the active metabolites of thiopurine therapy, and their monitoring has been considered a useful tool for optimizing response in inflammatory bowel diseases. Tioguanine (thioguanine) therapy results in much higher levels of 6-thioguanine-nucleotide levels when compared with azathioprine or mercaptopurine.Aim : To elucidate the influence of 6-thioguanine-nucleotide and methylated 6-thioguanine-nucleotide levels under tioguanine on efficacy and toxicity in Crohn's disease.Methods : 6-Thioguanine-nucleotide and methylated 6-tioguanine-nucleotide levels were measured regularly in 26 Crohn's disease patients treated with tioguanine. Nucleotide levels were related to efficacy and toxicity.Results : 6-Thioguanine-nucleotide levels rose very high [median 1241 pmol/8 × 108 red blood cells (range 313–1853)]. Methylated 6-thioguanine-nucleotide levels were detected in all patients [491 pmol/8 × 108 red blood cells (154–1775)]. 6-Thioguanine-nucleotide and methylated 6-thioguanine-nucleotide concentrations correlated significantly (r = 0.7, P 〈 0.0001). Nucleotide levels from patients achieving remission (n = 14) did not differ significantly from non-remitters (n = 12) [6-thioguanine-nucleotide: 1077 (599–2160) vs. 1210 (534–4665); methylated 6-thioguanine-nucleotide: 510 (214–1222) vs. 421 (145–1284)]. One patient with intermediate thiopurine S-methyltransferase activity experienced bone marrow toxicity upon dose escalation parallel with excessively high thioguanine-nucleotide levels.Conclusions : 6-Thioguanine-nucleotide as well as methylated 6-thioguanine-nucleotide levels under tioguanine therapy were not related to efficacy. This suggests that monitoring of 6-thioguanine-nucleotide levels is not a useful tool to predict response to thiopurines.

Notes: Triple therapy including two antibiotics and a proton pump inhibitor is a rational approach to the treatment of Helicobacter pylori induced peptic ulcer disease. The interaction of antimicrobial therapy and acid suppression is not yet well elucidated.〈section xml:id="abs1-2"〉〈title type="main"〉Aims:To investigate the effects of proton pump inhibitors on roxithromycin levels in plasma and gastric tissue under steady-state conditions in volunteers.〈section xml:id="abs1-3"〉〈title type="main"〉Methods:In two crossover studies omeprazole 20 mg b.d., lansoprazole 30 mg b.d., roxithromycin 300 mg b.d., and the combination of roxithromycin with either omeprazole or lansoprazole were administered to 12 healthy volunteers over 6 days. Blood plasma levels of the drugs were measured. In addition, roxithromycin concentrations were also determined in gastric juice and gastric tissue obtained during endoscopy.〈section xml:id="abs1-4"〉〈title type="main"〉Results:The proton pump inhibitors and roxithromycin did not alter the blood plasma pharmacokinetics of each other. When compared to roxithromycin administered alone, its combination with a proton pump inhibitor significantly increased the roxithromycin concentrations in gastric juice (3.0–5.0 μg/mL vs. 0.3–0.4 μg/mL) and gastric tissue (antrum: 3.8–4.0 vs. 2.8 μg/g, fundus: 5.9–7.4 vs. 4.2–4.4 μg/g).〈section xml:id="abs1-5"〉〈title type="main"〉Conclusions:Proton pump inhibitors and roxithromycin do not alter the systemic bioavailability of each other. However, proton pump inhibitors increase the local concentration of roxithromycin in the stomach which may contribute to the clinically proven synergic beneficial action in eradication therapy of H. pylori.

Notes: In osteoarthritis (OA), cartilage and bone fragments have been described within the synovial tissue which are surrounded by synovial cells (i.e. detritus synovitis). These cells appear to attach actively to the cartilage and bone fragments. In rheumatoid arthritis (RA), on the other hand, synovial fibroblasts (SF) have also been shown to be localized at sites of invasion into cartilage and bone and to degrade extracellular matrix (ECM) by secreting proteolytic enzymes. One prerequisite for exerting their aggressive properties is the attachment to cartilage and bone ECM. This attachment appears to be mediated by the expression of different adhesion molecules for which corresponding binding sites on ECM components are known. As it has not been addressed to which ECM proteins SF adhere and with which affinity this process takes place, we investigated the adherence of SF from patients with OA and RA to different cartilage and bone matrix proteins. Synovial tissue samples were obtained during synovectomy or arthroplastic surgery and used for isolating and culturing SF. Synovial cells attaching to cartilage/bone fragments were characterized using immunohistochemistry. The adherence of SF to ECM proteins was examined using an adhesion assay with the following proteins coated on 96-well plates: aggrecan (AGG), bone sialoprotein (BSP), cartilage oligomeric matrix protein (COMP), collagen type I, II and VI, proline arginine-rich, end leucine-rich repeat protein (PRELP), osteopontin (OPN) and recombinant chondroadherin (CHAD). Bovine serum albumin was used as negative control. In addition, adhering fibroblasts were photographed using a phase-contrast microscope. As compared with RA-SF, significantly higher numbers of OA-SF adhering to collagen type II, OPN and CHAD could be detected (P 〈 0.05). In contrast, RA-SF showed increased attachment to collagen type II, OPN and BSP. Adhesion to AGG, COMP and PRELP appeared not to be significantly increased and differed widely among the SF samples, and, apart from one exception (BSP), OA-SF adhered in higher numbers to the matrix proteins than did RA-SF. Using immunohistochemistry, synovial cells attached to cartilage/bone fragments could be shown to predominantly express CD68 (≥50%). The CD68-negative population was of the fibroblast phenotype (AS02 positive). The study demonstrates that the binding pattern of OA-SF and RA-SF to ECM proteins differs considerably and therefore provides novel insights into the difficult pathophysiology of OA and RA. In general, it appeared that SF adhere primarily to ECM proteins that contain known binding sites for adhesion molecules (e.g. integrins: collagen/integrin α2β1) and that higher numbers of OA-SF adhered to the cartilage and bone matrix proteins than did RA-SF.

Notes: Macrophages play a central role in establishing a specific immune response by acting as professional antigen presenting cells (APC) for T cells leading to a vigorous immune response. In order to analyze if Herpes simplex Virus (HSV) type 1 infection might affect the macrophage APC-function, monocyte-derived human macrophages were infected with HSV-1 strain F in vitro. Cocultures with allogeneic T cells revealed a strongly impaired stimulatory capacity of HSV-infected macrophages compared to uninfected controls which was not owing to a productive viral infection in macrophages. An increased expression of Fas ligand (FasL/CD95L) was detected in HSV-infected macrophages by FACS analysis. Although the majority of the macrophages expressed high levels of Fas (CD95/Apo-1), the HSV-induced upregulation of FasL did not result in an increased autocrine apoptosis of macrophages which might be related to endogenous expression of the apoptosis inhibitor FLICE inhibitory protein (FLIP). However, substantial apoptosis occurred in peripheral T cells as well as Fas-sensitive Jurkat T cells when cocultured with HSV-infected macrophages. These findings suggest that the paracrine killing of activated T cells by FasL expressing APC might be a novel strategy of immune evasion by HSV.

Notes: In this study, we explored the everyday experiences of 40 infants from families who migrated recently from Central America to the US. Another 42 infants from middle class families of Euro-American background were included to facilitate the evaluation of our methodology and findings. Detailed descriptions of the previous 24 hours were obtained by interviewing the mothers when their infants were 8 and 12 months of age. The infants' experiences and activities were very similar in both groups, and the effects of the mothers', fathers' or others' presence on ongoing activities were similar, too. The groups differed with regard to (1) the circadian distribution of activities, (2) opportunities for interactions with various people, and (3) the differences between weekdays and weekends. Overall, the social worlds of the Central American children were characterized by the simultaneous presence of several people and thus by multiple social partners. The social worlds of the Euro-American children were characterized by more opportunities for dyadic interactions and by exposure to fewer partners.