Galectin-1 is overexpressed in nasal polyps under budesonide and inhibits eosinophil migration

Because of the importance of galectins for various cellular activities, the influence of the glucocorticoid budesonide on the level of expression of galectins-1 and -3 was investigated in human nasal polyposis. Ten nasal polyps obtained from surgical resection were maintained for 24 hours in the presence of various concentrations of budesonide. As quantitatively demonstrated by means of computer-assisted microscopy, 250 ng/ml (the highest dose tested) induced a pronounced increase of galectin-1 expression. This feature was observed in nasal polyps from allergic patients but not in those from nonallergic patients. Since eosinophils represent the main inflammatory cell population in nasal polyps, we investigated the effect of galectin-1 on their migration levels by means of quantitative phase-contrast computer-assisted videomicroscopy. Our results show that galectin-1 (coated on plastic supports) markedly reduced the migration levels of eosinophils in comparison to P-selectin. On the cellular level, marked modifications in the polymerization/depolymerization dynamics of the actin cytoskeleton (as revealed by means of computer-assisted fluorescence microscopy) and, to a much lesser extent, an increase in the adhesiveness of eosinophils to tested substrata were detectable. The present study therefore reveals a new galectin-1-mediated mechanism of action for glucocorticoid-mediated anti-inflammatory effects.     

Migration of lymphoblasts to the small intestine. III. Strain differences and relationship to distribution and duration of Trichinella spiralis infection.

In NIH strain mice, in which the majority of Trichinella spiralis are located in the anterior half of the small intestine early in the enteral phase of infection, enhanced localization of mesenteric lymphoblasts, nylon wool separated mesenteric T-lymphoblasts and even oxazolone sensitized peripheral lymphoblasts is most prominent in the anterior region of the small intestine. As the worms move to the posterior half of the small intestine, enahnced localization of lymphoblasts is observed in that region only. In BALB/c mice, in which most of the worms are located in the posterior half of the small intestine, enhanced localization of lymphoblasts is primarily in that region. Expulsion of the worms commences within 2--3 days of a large increase in the number of lymphoblasts localizing in the anterior region of the small intestine in NIH strain mice and likewise follows a second and larger increase in the number of lymphoblasts localizing in the posterior region of the small intestine of BALB/c mice.     

Modulation of Bcl-2 family proteins in primary endothelial cells during apoptosis

We studied the expression of Bcl-2 family proteins during cytokine- and verotoxin (VT)-induced apoptosis in primary human umbilical vein endothelial cells (HUVECs). Our experiments demonstrated that high initial expression of Bcl-2 protein was significantly downregulated in HUVECs treated with IFN-gamma whereas TNF-alpha gave a less pronounced decrease in Bcl-2 level. Treatment with the combination of cytokines was more efficient in downregulating Bcl-2 protein. HUVECs pretreated with cytokines and incubated with VT gave a further significant decrease in Bcl-2 level. Simultaneous measurement of Bcl-xl level did not reveal any significant changes. Bax protein was upregulated in HUVECs stimulated with TNF-alpha alone or in combination with IFN-gamma. However, addition of VT did not give any further increase in Bax level suggesting that Bax upregulation is more important for cytokine- rather than VT-mediated apoptosis. Total endothelial cell growth factor deprivation gave a significant increase in apoptosis accompanied by a decrease of Bcl-2 in apoptotic cells while Bcl-xl and Bax levels were unaffected. Our data indicate that anti-apoptotic protein Bcl-2 and pro-apoptotic protein Bax are reciprocally regulated during apoptosis, whilst Bcl-xl is essentially unaffected. This implies that Bcl-2/Bax ratio rather than Bcl-xl controls apoptosis in primary endothelial cells.     

The influence of the herpes simplex virus-1 DNA template environment on the regulation of gene expression

To determine the role of the HSV-1 genome structure and environment on the regulation of gene expression, we constructed recombinant viruses containing a heterologous gene inserted into either the immediate early ICP0 or late glycoprotein C (gC) genes of HSV-1. The heterologous gene consisted of the SV40 early promoter (without enhancer sequences) linked to the coding sequences for the bacterial chloramphenicol acetyl transferase (CAT). The expression of CAT was examined in Vero cells infected with either virus (named ICP0-CAT and Sph 6). For both recombinants, expression of CAT was not dependent upon prior viral protein synthesis. The kinetics of expression of CAT-specific mRNA resembled that of the HSV-1 genes into which CAT was inserted. Primer extension analysis revealed that the SV40 promoter is recognized and used when placed in cis in two different HSV-1 genome locations, and Northern hybridization experiments confirmed that the heterologous gene was expressed in the absence of prior viral protein synthesis. Therefore, this gene was not regulated as strictly as an HSV-1 gene, but was influenced by the environment into which it was placed, presumably by factors that are present when the normal viral gene is on.     

Antimicrobial use and outcomes in patients with multidrug-resistant and pansusceptible Salmonella Newport infections, 2002-2003

Multidrug-resistant Salmonella Newport with decreased susceptibility to ceftriaxone (MDR-AmpC) is becoming increasingly common in its food animal reservoirs and in humans. Few data exist on rates of antimicrobial use or differences in clinical outcomes in persons infected with MDR-AmpC or other Salmonella strains. We conducted a case-comparison analysis of data from a multistate population-based case-control study to identify antimicrobial treatment choices and differences in clinical outcomes in those infected with MDRAmpC compared to pansusceptible S. Newport. Of isolates from 215 laboratory-confirmed S. Newport cases, 54 (25%) were MDR-AmpC, 146 (68%) were pansusceptible, and 15 (7%) had other resistance patterns; 146 (68%) patients with S. Newport were treated with antimicrobial agents and 66 (33%) were hospitalized. Over two-thirds of cases at low-risk for serious complications received antimicrobial therapy, most commonly with fluoroquinolones, to which this strain was susceptible. There were no significant differences in symptoms, hospitalization, duration of illness, or other outcomes between the persons infected with MDR-AmpC and pansusceptible S. Newport. Although currently prevalent MDR-AmpC S. Newport strains remains susceptible to the antimicrobial most commonly prescribed for it, continued efforts to reduce unnecessary use of antimicrobial agents in food animals and humans are critical to prevent further development of resistance to quinolones and cephalosporins, which is likely to lead to substantial adverse outcomes.     

Enhanced Toxicity for Mice of Combinations of Antibiotics with Escherichia coli Cells or Salmonella typhosa Endotoxin

Enhanced lethality for BALB/c mice has been observed after the administration of Salmonella typhosa endotoxin with either actinomycin D, cycloheximide, or nogalamycin. The dose of actinomycin D required to kill half of the mice (LD₅₀) was 0.8 mg/kg in normal animals, 0.35 mg/kg in mice administered 0.08 mg of endotoxin per kg, and 0.28 mg/kg in mice administered 0.2 mg of endotoxin per kg. The LD₅₀ of endotoxin in normal mice was 12 mg/kg and in mice given 0.4 mg of actinomycin D per kg was 0.067 mg/kg. The LD₅₀ of actinomycin D in mice administered 1.8 × 10⁸ live Escherichia coli cells per kg or 1.8 × 10⁹ heat-killed E. coli cells per kg was reduced to 0.4 mg/kg. The LD₅₀ of cycloheximide was 181 mg/kg in normal animals and 28 mg/kg in mice administered 4 mg of endotoxin per kg. The LD₅₀ of endotoxin in mice given 120 mg of cycloheximide per kg was 0.02 mg/kg. Enhanced lethality due to various combinations of cycloheximide and endotoxin was abolished by pretreatment of mice with endotoxin. The LD₅₀ of nogalamycin was 21 mg/kg in normal mice and 13 mg/kg in mice receiving 1 mg of endotoxin per kg.     

Study of nuclear diameters in non-Hodgkin's lymphomas

The mean maximum nuclear diameter (D_max) in 21 cases of non-Hodgkin's lymphoma (NHL) has been determined, using the Reichert-Jung (Kontron) MOP-AMO₃ user-controlled image analyser. Nuclear diameters of high-grade malignancy NHL were found to be considerably greater than those of low-grade malignancy lymphomas, although there was some overlap of their ranges. These findings confirm objectively subjective estimates of nuclear size in NHL. The relative usefulness of the user-controlled (interactive) image analyser for the measurement of nuclei in tissue sections is compared with that of a fully automatic machine.     

Stress and immune mediators in miscarriage.

BACKGROUND: Stress is thought to be abortogenic and psycho-neuro-immunological pathways have been suggested to be involved in triggering miscarriages. From experiments in pregnant mice exposed to stress some insights into the underlying mechanisms have been gained, delineating immunological imbalances as a cause of pregnancy failure. In order to test the validity of the conclusions drawn from murine experiments and the role of stress in human pregnancy loss, the following study was performed. METHODS: We used an established perceived stress questionnaire and measured the stress score of women with a confirmed diagnosis of first trimester spontaneous abortion (n = 94). Decidual tissue was investigated by immunohistochemistry and in-situ hybridization to detect the presence and distribution of immunocompetent decidual cells [CD56(+) natural killer (NK) cells, CD8(+)and CD3(+) T cells, tryptase(+) mast cells (MCT(+)) and tumour necrosis factor (TNF)-alpha(+) cells]. The patient cohort was divided into women experiencing low or high levels of stress. RESULTS: In the decidua of women with high stress scores we observed significantly higher numbers of MCT(+), CD8(+) T cells and TNF-alpha(+) cells per mm(2) tissue (P < or = 0.05). No significant differences between individuals with lower or higher stress scores could be observed with respect to decidual CD56(+) NK and CD3(+) T cells. CONCLUSIONS: Using a questionnaire to score perceived stress in humans may be a valid approach to assess non-biased stress scores. Stress-triggered abortion in humans, identified by a questionnaire, can be linked to immunological imbalances.