Neutrophils must adhere to the vessel wall, migrate, and degranulate in an ordered manner to perform their protective function. Disruption of these processes may be pathogenic. Current knowledge of the degranulation process is derived almost exclusively from studies on neutrophils in suspension, in which priming with the nonphysiological agent cytochalasin <em>B</em> is necessary to obtain elastase release in response to activating agents. To avoid this, we have adopted a different approach. Using a novel flow-based adhesion system, we have been able to quantify the release of elastase from the primary granules of activated neutrophils adherent to immobilized platelets or purified receptors without priming. Comparing stimuli, formyl tripeptide (fMLP), interleukin-8 (IL-8), activated complement fragment C5a, and platelet-activating factor (PAF) all induced rapid conversion to CD11b/CD18 (MAC-1) -mediated stationary adhesion when perfused over neutrophils already rolling on platelet monolayers or purified P-selectin. However, fMLP, C5a, and IL-8, but not PAF, induced release of elastase from the adherent cells in minutes. Neutrophils stimulated in suspension showed little degranulation. Treatment of neutrophils with an inhibitor of 5-lipoxygenase-activating protein (MK886) and thus synthesis of leukotrienes (<em>LTs</em>) or with an antagonist of the LT<em>B</em>4 receptor (LY223982) blocked the release of elastase. This indicated that endogenous synthesis of 5-lipoxygenase products such as <em>LTs</em> and autocrine activation of neutrophils was required for fMLP-driven elastase release. We hypothesize that the differential ability of PAF and fMLP to induce elastase release from surface-adherent neutrophils could arise from differential ability to generate leukotrienes, such as LT<em>B</em>4, and would be an appropriate mechanism for the control of elastase release during inflammation in vivo, where it is important that cytotoxic agents are not released until activated neutrophils have migrated into the extravascular tissues.

We studied the urinary excretion of the isoprostane 8-iso-prostaglandin F(2alpha) as an index of in vivo oxidant stress, and the production of leukotriene (LT) B(4) (LTB(4)) by neutrophils in subjects with chronic obstructive pulmonary disease (COPD) and normal subjects. Overnight urinary excretion of the isoprostane was significantly higher in patients with COPD than in control subjects, and LTB(4) production by challenge of neutrophils obtained from patients with COPD was also significantly higher than that observed in control neutrophils. Treatment with a standardized polyphenol extract caused a significant decrease in isoprostane excretion, accompanied by a statistically significant increase of Pa(O(2)). Furthermore, changes in FEV(1) significantly correlated with the changes in isoprostane urinary excretion observed from enrollment to the end of treatment. The results of this study suggest that enhanced oxidative stress in subjects with COPD is paralleled by the increased ability of neutrophils to synthesize the chemotactic factor LTB(4), and may ultimately contribute to the infiltration/activation of neutrophils into the airways of subjects with COPD. Antioxidant treatment in subjects with COPD is effective in reducing oxidant stress as shown by the decrease of urinary isoprostane, a reduction that correlates with the severity of the disease, as indicated by changes in Pa(O(2)) and FEV(1).

Different activation parameters of peripheral blood mononuclear cells (PBMC) from 31 patients with oral lichen planus (OLP) were examined and compared with 23 healthy donors. Impaired spontaneous (450 +/- 241 vs 1290 +/- 480 cpm) and mitogen-induced (39580 +/- 14470 vs 67000 +/- 11810 cpm) lymphocyte blastogenesis was observed in OLP patients. Furthermore, reduced cytokine production was found after phytohemagglutinin A (PHA) stimulation for all cytokines studied-tumour necrosis factor alpha (TNF alpha, 432.2 +/- 73.4 vs 979.8 +/- 46.3 units/ml), interleukin 2 (IL-2, 156.2 +/- 14.9 vs 572.6 +/- 12.9 pg/ml), interferon gamma (IFN gamma, 48.5 +/- 11.9 vs 82.6 +/- 12.4 pg/ml) and interleukin 6 (IL-6, 253.6 +/- 57.7 vs 1,419.0 +/- 279.6 units/ml)-except for interleukin 1 beta (IL-1 beta) and lymphotoxin (LT). In contrast, unstimulated culture supernatants showed increased TNF alpha (38.2 +/- 13.1 vs 8.0 +/- 0.2 units/ml), LT (10.2 +/- 2.2 units/ml vs < 0.4) and IL-6 (18.5 +/- 5.6 units/ml vs < 0.5) activity. Similarly, elevated concentrations of TNF alpha (19.6 +/- 6.3 units/ml) and IL-6 (22.9 +/- 4.7 units/ml) were detected in the sera of OLP patients. Combination of PHA and phorbol myristate acetate (PMA) could restore OLP proliferative T cell response and cytokine production to the level of healthy donors, whereas exogenous recombinant human IL-2 (rhuIL-2) plus PMA did not seem to be an effective stimulant for OLP T cells. These results indicate an alteration in the immune condition of OLP patients and an impairment in T lymphocyte function.

Low-temperature (LT) induced genes of the Wcs120 family in wheat (Triticum aestivum) were mapped to specific chromosome arms using Western and Southern blot analysis on the ditelocentric series in the cultivar Chinese Spring (CS). Identified genes were located on the long arms of the homoeologous group 6 chromosomes of all 3 genomes (A, B, and D) of hexaploid wheat. Related species carrying either the A, D, or AB genomes were also examined using Southern and Western analysis with the Wcs120 probe and the WCS120 antibody. All closely related species carrying one or more of the genomes of hexaploid wheat produced a 50 kDa protein that was identified by the antibody, and a Wcs120 homoeologue was detected by Southern analysis in all species. In the absence of chromosome arm 6DL in hexaploid CS wheat no 50 kDa protein was produced and the high-intensity Wcs120 band was missing, indicating 6DL as the location of Wcs120 but suggesting silencing of the Wcs120 homoeologue in the A genome. Levels of proteins that cross-reacted with the Wcs120 antibody and degrees of cold tolerance were also investigated in the Chinese Spring/Cheyenne (CS/CNN) chromosome substitution series. CNN chromosome 5A increased the cold tolerance of CS wheat. Densitometry scanning of Western blots to determine protein levels showed that the group 5 chromosome 5A had a regulatory effect on the expression of the Wcs120 gene family located on the group 6 chromosomes of all three hexaploid wheat genomes.

Liver transplantation (LT) is the treatment of choice for end-stage liver disease, but is controversial in patients with human immunodeficiency virus (HIV) infection. Using a prospective cohort of HIV-hepatitis B virus (HBV) coinfected patients transplanted between 2001-2007; outcomes including survival and HBV clinical recurrence were determined. Twenty-two coinfected patients underwent LT; 45% had detectable HBV DNA pre-LT and 72% were receiving anti-HBV drugs with efficacy against lamivudine-resistant HBV. Post-LT, all patients received hepatitis B immune globulin (HBIG) plus nucleos(t)ide analogues and remained HBsAg negative without clinical evidence of HBV recurrence, with a median follow-up 3.5 years. Low-level HBV viremia (median 108 IU/mL, range 9-789) was intermittently detected in 7/13 but not associated with HBsAg detection or ALT elevation. Compared with 20 HBV monoinfected patients on similar HBV prophylaxis and median follow-up of 4.0 years, patient and graft survival were similar: 100% versus 85% in HBV mono- versus coinfected patients (p = 0.08, log rank test). LT is effective for HIV-HBV coinfected patients with complications of cirrhosis, including those who are HBV DNA positive at the time of LT. Combination HBIG and antivirals is effective as prophylaxis with no clinical evidence of HBV recurrence but low-level HBV DNA is detectable in approximately 50% of recipients.

The effects of crude lymphokine-enriched supernatants, purified recombinant lymphotoxin (LT), tumor necrosis factor-alpha (TNF), and gamma interferon (gamma IF) on proliferating human keratinocytes were assessed using two in vitro culture systems. Activated splenocyte supernatants inhibited keratinocyte colony growth on fibroblast feeder layers and arrested basal keratinocyte DNA synthesis within 24 h. Purified recombinant LT, TNF, and gamma IF inhibited cell proliferation in serum-free medium without noticeably affecting viability. Cytostasis was dose-dependent (up to 90% with LT or TNF and 99% with gamma IF) and was maximal within 24-36 h. Specific antibodies neutralized TNF- and gamma IF-mediated cytostasis. Combined treatment with LT (or TNF) and gamma IF increased the degree of cytostasis, particularly at low lymphokine concentrations. Maximum inhibition of DNA synthesis and the duration of exposure required for this inhibition were comparable for LT and TNF and differed for gamma IF. Each of these lymphokines induced cell enlargement, flattening, and vesiculation, with gamma IF apparently more potent in this respect than LT or TNF. Fusiform keratinocytes with diffusely distributed cytokeratin were observed after prolonged treatment with gamma IF alone or gamma IF plus either LT or TNF. Flow cytometric studies of lymphokine-treated keratinocytes indicated that LT, TNF, and gamma IF could enhance beta-2 microglobulin expression 1.5-fold to threefold, whereas only gamma IF induced class II antigens. Staining for class II and beta-2 microglobulin was reduced on cells treated with high concentrations of gamma IF compared with either optimally treated or untreated cells. The potential relevance of these findings to cutaneous immune defense and disease is discussed.

Carboxypeptidase E (CPE) is involved in peptide processing in the brain and various neuroendocrine tissues. In mice homozygous for the Cpefat mutation, the virtual absence of CPE activity in islets of Langerhans and pituitary was associated with a missense mutation effecting a Ser202 to Pro shift (Naggert, J. K., Fricker, L. D., Varlamov, O., Nishina, P. M., Rouille, Y., Steiner, D. F., Carroll, R. J., Paigen, B. J., and Leiter, E. H. (1995) Nat. Genet. 10, 135-142). To examine the importance of Ser202 in CPE function, several mutations in this position were generated (Pro202, Ala202, Gly202, and Phe202). When the mutant proteins were expressed in a Baculovirus system, both Phe202 and Pro202CPE were enzymatically inactive, were unable to bind to a substrate affinity column, and were not secreted from Sf9 cells. In contrast, Ala202CPE or Gly202CPE exhibited enzymatic properties similar to those of wild-type CPE and were secreted from Sf9 cells. When expressed in AtT-20 cells, a mouse pituitary-derived cell line, CPE with Pro202 and Phe202 were not secreted. Pulse-chase analysis with [35S]Met indicated that Pro202CPE was degraded in AtT-20 cells within several hours. This degradative process was blocked by incubation at 15 degrees C but not by brefeldin A or by lysosomotrophic drugs. Pulse-chase analysis using dispersed pituitary cells from C57BLKS/Lt-Cpefat/Cpefat mutant mice shows similar results; Pro202-CPE produced in these cells was not secreted but rather was degraded within 5 h. Immunofluorescence analysis of epitope-tagged CPE revealed Ser202CPE to be present primarily in secretory vesicles, whereas Pro202CPE was localized to the endoplasmic reticulum and not the secretory vesicle-like structures. These results support the previous finding that Cpefat/Cpefat mice are defective in CPE activity because of the point mutation producing the Ser202 to Pro substitution. Furthermore, these results are consistent with a model that Ser202 is important for the intracellular folding of CPE.

T lymphocytes play a central role in controlling adaptive immune responses. IL-2 critically regulates both T cell growth and death and is involved in maintaining peripheral tolerance, but the molecules involved in these and other IL-2 actions are only partially known. We now provide a comprehensive compendium of the genes expressed in T cells and of those regulated by IL-2 based on a combination of DNA microarrays and serial analysis of gene expression (SAGE). The newly identified IL-2 target genes include many genes previously linked to apoptosis in other cellular systems that may contribute to IL-2-dependent survival functions. We also studied the mRNA expression of known regulators of signaling pathways for their induction in response to IL-2 in order to identify potential novel positive and/or negative feedback regulators of IL-2 signaling. We show that IL-2 regulates only a limited number of these genes. These include suppressors of cytokine signaling (SOCS) 1, SOCS2, dual-specificity phosphatase (DUSP) 5, DUSP6 and non-receptor type phosphatase-7 (PTPN7). Additionally, we provide evidence that many genes expressed in T cells locate in chromosomal clusters, and that select IL-2-regulated genes are located in at least two clusters, one at 5q31, a known cytokine gene cluster, and the other at 6p21.3, a region that contains genes encoding the tumor necrosis factor (TNF) superfamily members TNF, LT-alpha and LT-beta.

Escherichia coli heat-labile enterotoxin (labile toxin, LT) catalyzed the hydrolysis of NAD to ADP-ribose and nicotinamide and the ADP-ribosylation of arginine (Moss, J., and Richardson, S.H. (1978) J. Clin. Invest. 62, 281-285). Analysis of the product of the ADP-ribosylation of arginine by nuclear magnetic resonance spectroscopy indicated that the reaction was stereospecific and resulted in the formation of alpha-ADP-ribosyl-L-arginine. This reaction product rapidly anomerized to yield a mixture of the alpha and beta forms. In the presence of [adenine-U-14C]NAD, E. coli enterotoxin catalyzed the transfer of the radiolabel to proteins; the ADP-ribosylation of proteins was inhibited by arginine methyl ester, an alternative substrate. Digestion of the 14C-protein with snake venom phosphodiesterase released predominantly 5'-AMP. No product was obtained with a mobility similar to that of 2'-(5''-phosphoribosyl)-5'-AMP. This result is consistent with the covalent attachment by the enterotoxin of ADP-ribose rather than poly(ADP-ribose) to protein. Thus, LT is catalytically equivalent to choleragen, an enterotoxin of Vibrio cholerae, and activates adenylate cyclase through a similar stereospecific ADP-ribosylation reaction.

Lethal toxin (LT) is a critical virulence factor of Bacillus anthracis, the etiological agent of anthrax, whose pulmonary form is fatal in the absence of treatment. Inflammatory response is a key process of host defense against invading pathogens. We report here that intranasal instillation of a B. anthracis strain bearing inactive LT stimulates cytokine production and polymorphonuclear (PMN) neutrophils recruitment in lungs. These responses are repressed by a prior instillation of an LT preparation. In contrast, instillation of a B. anthracis strain expressing active LT represses lung inflammation. The inhibitory effects of LT on cytokine production are also observed in vitro using mouse and human pulmonary epithelial cells. These effects are associated with an alteration of ERK and p38-MAPK phosphorylation, but not JNK phosphorylation. We demonstrate that although NF-kappaB is essential for IL-8 expression, LT downregulates this expression without interfering with NF-kappaB activation in epithelial cells. Histone modifications are known to induce chromatin remodelling, thereby enhancing NF-kappaB binding on promoters of a subset of genes involved in immune response. We show that LT selectively prevents histone H3 phosphorylation at Ser 10 and recruitment of the p65 subunit of NF-kappaB at the IL-8 and KC promoters. Our results suggest that B. anthracis represses the immune response, in part by altering chromatin accessibility of IL-8 promoter to NF-kappaB in epithelial cells. This epigenetic reprogramming, in addition to previously reported effects of LT, may represent an efficient strategy used by B. anthracis for invading the host.

Cross-resistance to cefoxitin (FOX), chloramphenicol (CMP), and quinolones (nalidixic acid [NAL]) related to a putative efflux system overexpression has recently been reported for Klebsiella pneumoniae. The potential impact of this multidrug resistance (MDR) on the virulence of K. pneumoniae was evaluated in the Caenorhabditis elegans model. For 2 of the 3 MDR clinical isolates studied, a significant increase in acrB transcription was found in comparison with their antibiotic-susceptible revertants. ATCC 138821 and MDR, revertant, and derivative strains with altered porin expression were studied. Strains proved or suspected to overexpress an efflux system were significantly more virulent than the ATCC and revertant strains (time to kill 50% of nematodes [LT(50)] in days: 3.4 to 3.8 ± 0.2 versus 4.1 to 4.4 ± 0.3, P < 0.001). Inversely, strains with altered porin expression were significantly less virulent, independently of the expression level of efflux system (LT(50) = 5.4 to 5.6 ± 0.2, P < 0.001). Altered porin expression did not change MICs of CMP and NAL but did those of FOX (4 to 16× MIC) and ertapenem (16 to 64× MIC). The strains with a normally or an overexpressed efflux system that received the β-lactamase CTX-M-15 became more widely resistant without modification of their virulence potential, suggesting that balance between resistance and virulence is dependent on the type of resistance mechanisms. In conclusion, this study shows that the expression of both efflux systems and porins is a key factor not only for antibiotic resistance but also virulence potential in K. pneumoniae.

<p><div>(<em>b</em>)Background</<em>b</em>)</div>The glo<em>b</em>al emergence and spread of extended-spectrum <em>beta</em>-lactamases (ESBLs) producing <i>Entero<em>b</em>acteriaceae</i> have <em>b</em>een threatening the a<em>b</em>ility to treat an infection. Hence, this study aimed to determine the prevalence of ESBL-producing and mu<em>lt</em>i-drug resistance (MDR) <i>Entero<em>b</em>acteriaceae</i> (ESBLs-E) from different clinical specimens in Addis A<em>b</em>a<em>b</em>a, Ethiopia.</p><p><div>(<em>b</em>)Methods</<em>b</em>)</div>A cross-sectional study was conducted from January 1 to May 30, 2017. A total of 426 <i>Entero<em>b</em>acteriaceae</i> isolates were identified from clinical specimens. The isolates were collected from four la<em>b</em>oratories. Antimicro<em>b</em>ial suscepti<em>b</em>ility testing was performed using the Kir<em>b</em>y-Bauer disk diffusion method on Muller Hinton agar (MHA). All <i>Entero<em>b</em>acteriaceae</i> were screened for ESBLs production using cefotaxime and ceftazidime as per CLSI guideline. Each ESBL screening positive <i>Entero<em>b</em>acteriaceae</i> were confirmed <em>b</em>y a com<em>b</em>ination disk test (CDT). Data were entered and analyzed <em>b</em>y using SPSS version-20.</p><p><div>(<em>b</em>)Resu<em>lt</em></<em>b</em>)</div>The most frequent <i>Entero<em>b</em>acteriaceae</i> were <i>E. coli</i> 228 (53.5%) and <i>K. pneumoniae</i> 103 (24.1%). The magnitude of ESBLs-E was 57.7% (246/426). The highest frequencies of ESBLs-E were o<em>b</em>served in <em>b</em>lood specimesns (84.4%) and the highest ESBLs production was o<em>b</em>served in <i>K. pneumoniae</i> (85.4%). The highest resistance level was seen to sulfamethoxazole-trimethoprim (77.0%), amoxicillin with clavulanic acid (71.6%), cefotaxime (62.2%), cefepime (60.3%) and ceftazidime (60.8%). The overall magnitude of mu<em>lt</em>i-drug resistance (MDR) level was 68.3%. Of ESBLs-E, 96.3% of them were MDR (<i>P</i> &<em>lt</em>; 0.001).</p><p><div>(<em>b</em>)Conclusion</<em>b</em>)</div>There was a high prevalence of ESBLs-E and MDR isolate in Addis A<em>b</em>a<em>b</em>a. Most of ESBLs-E was isolated primarily in <em>b</em>lood and urine. The highest ESBLs production was o<em>b</em>served among <i>K. pneumoniae</i>. Hence, strong infection control strategies must <em>b</em>e implemented in hospital settings of the country.</p>

The toxic effects of Eucalyptus globulus leaf oil-derived monoterpenoids [1,8-cineole, l-phellandrene, (-)-alpha-pinene, 2-beta-pinene, trans-pinocarveol, gamma-terpinene, and 1-alpha-terpineol] and the known Eucalyptusleaf oil terpenoids (beta-eudesmol and geranyl acetate) on eggs and females of the human head louse, Pediculus humanus capitis, were examined using direct contact and fumigation bioassays and compared with the lethal activity of delta-phenothrin and pyrethrum, two commonly used pediculicides. In a filter paper contact bioassay with female P. h. capitis, the pediculicidal activity was more pronounced with Eucalyptus leaf oil than with either delta-phenothrin or pyrethrum on the basis of LT(50) values (0.125 vs 0.25 mg/cm(2)). 1,8-Cineole was 2.2- and 2.3-fold more toxic than either delta-phenothrin or pyrethrum, respectively. The pediculicidal activities of (-)-alpha-pinene, 2-beta-pinene, and (E)-pinocarveol were comparable to those of delta-phenothrin and pyrethrum. l-Phellandrene, gamma-terpinene, and 1-alpha-terpineol were relatively less active than delta-phenothrin and pyrethrum. beta-Eudesmol and geranyl acetate were ineffective. 1-alpha-Terpineol and (E)-pinocaveol were highly effective at 0.5 and 1.0 mg/cm(2), respectively, against P. h. capitis eggs. At 1.0 mg/cm(2), (-)-alpha-pinene, 2-beta-pinene, and gamma-terpinene exhibited moderate ovicidal activity, whereas little or no ovicidal activity was observed with the other terpenoids and with delta-phenothrin and pyrethrum. In fumigation tests with female P. h. capitis at 0.25 mg/cm(2), 1,8-cineole, (-)-alpha-pinene, (E)-pinocarveol, and 1-alpha-terpineol were more effective in closed cups than in open ones, indicating that the effect of the monoterpenoids was largely due to action in the vapor phase. Neither delta-phenothrin nor pyrethrum exhibited fumigant toxicity. Eucalyptus leaf oil, particularly 1,8-cineole, 1-alpha-terpineol, and (E)-pinocaveol, merits further study as potential pediculicides or lead compounds for the control of P. h. capitis.

Pattern recognition receptors for fungi include dectin-1 and mannose receptor, and these mediate phagocytosis, as well as production of cytokines, reactive oxygen species, and the lipid mediator leukotriene <em>B</em>(4) (<em>LT</em><em>B</em>(4)). The influence of G protein-coupled receptor ligands such as <em>LT</em><em>B</em>(4) on fungal pattern recognition receptor expression is unknown. In this study, we investigated the role of <em>LT</em><em>B</em>(4) signaling in dectin-1 expression and responsiveness in macrophages. Genetic and pharmacologic approaches showed that <em>LT</em><em>B</em>(4) production and signaling through its high-affinity G protein-coupled receptor leukotriene <em>B</em>(4) receptor 1 (<em>B</em><em>LT</em>1) direct dectin-1-dependent binding, ingestion, and cytokine production both in vitro and in vivo. Impaired responses to fungal glucans correlated with lower dectin-1 expression in macrophages from leukotriene (<em>LT</em>)- and <em>B</em><em>LT</em>1-deficent mice than their wild-type counterparts. <em>LT</em><em>B</em>(4) increased the expression of the transcription factor responsible for dectin-1 expression, PU.1, and PU.1 small interfering RNA abolished <em>LT</em><em>B</em>(4)-enhanced dectin-1 expression. GM-CSF controls PU.1 expression, and this cytokine was decreased in <em>LT</em>-deficient macrophages. Addition of GM-CSF to <em>LT</em>-deficient cells restored expression of dectin-1 and PU.1, as well as dectin-1 responsiveness. In addition, <em>LT</em><em>B</em>(4) effects on dectin-1, PU.1, and cytokine production were blunted in GM-CSF(-/-) macrophages. Our results identify <em>LT</em><em>B</em>(4)-<em>B</em><em>LT</em>1 signaling as an unrecognized controller of dectin-1 transcription via GM-CSF and PU.1 that is required for fungi-protective host responses.

Two plasmid vectors encoding the A and B subunits of cholera toxin (CT) and two additional vectors encoding the A and B subunits of the Escherichia coli heat-labile enterotoxin (LT) were evaluated for their ability to serve as genetic adjuvants for particle-mediated DNA vaccines administered to the epidermis of laboratory animals. Both the CT and the LT vectors strongly augmented Th1 cytokine responses (gamma interferon [IFN-gamma]) to multiple viral antigens when codelivered with DNA vaccines. In addition, Th2 cytokine responses (interleukin 4 [IL-4]) were also augmented by both sets of vectors, with the effects of the LT vectors on IL-4 responses being more antigen dependent. The activities of both sets of vectors on antibody responses were antigen dependent and ranged from no effect to sharp reductions in the immunoglobulin G1 (IgG1)-to-IgG2a ratios. Overall, the LT vectors exhibited stronger adjuvant effects in terms of T-cell responses than did the CT vectors, and this was correlated with the induction of greater levels of cyclic AMP by the LT vectors following vector transfection into cultured cells. The adjuvant effects observed in vivo were due to the biological effects of the encoded proteins and not due to CpG motifs in the bacterial genes. Interestingly, the individual LT A and B subunit vectors exhibited partial adjuvant activity that was strongly influenced by the presence or absence of signal peptide coding sequences directing the encoded subunit to either intracellular or extracellular locations. Particle-mediated delivery of either the CT or LT adjuvant vectors in rodents and domestic pigs was well tolerated, suggesting that bacterial toxin-based genetic adjuvants may be a safe and effective strategy to enhance the potency of both prophylactic and therapeutic DNA vaccines for the induction of strong cellular immunity.

BACKGROUND

This phase II study investigated efficacy and safety of weekly alternating Bevacizumab (BEV)/Irinotecan (CPT-11) or Oxaliplatin (OHP) associated to weekly 5-Fluorouracil (5-FU) in first line treatment of metastatic colorectal carcinoma (MCRC).

METHODS

Simon two-step design: delta 20% (p0 50%, p1 70%), power 80%, α 5%, β 20%. Projected objective responses (ORR): I step, 8/15 patients (pts); II step 26/43 pts. Schedule: weekly 12 h-timed-flat-infusion/5-FU 900 mg/m2, days 1-2, 8-9, 15-16, 22-23; CPT-11 160 mg/m2 plus BEV 5 mg/kg, days 1,15; OHP at three dose-levels, 60-70-80 mg/m2, days 8, 22; every 4 weeks.

RESULTS

Fifty consecutive, unselected pts < 75 years were enrolled: median age 63; young-elderly (yE) 24 (48%); liver metastases (LM) 33 pts, 66% Achieved OHP recommended dose, 80 mg/m2. ORR 82% intent-to-treat and 84% as-treated analysis. Median progression-free survival 12 months. Equivalent efficacy was obtained in yE pts. Liver metastasectomies were performed in 26% of all pts and in 39% of pts with LM. After a median follow-up of 21 months, median overall survival was 28 months. Cumulative G3-4 toxicities per patient: diarrhea 28%, mucositis 6%, neutropenia 10%, hypertension 2%. They were equivalent in yE pts. Limiting toxicity syndromes (LTS), consisting of the dose-limiting toxicity, associated or not to G2 or limiting toxicities: 44% overall, 46% in yE. Multiple versus single site LTS, respectively: overall, 24% versus 20%; yE pts, 37.5% versus 8%.

CONCLUSIONS

Poker combination shows high activity and efficacy in first line treatment of MCRC. It increases liver metastasectomies rate and can be safely administered.

BACKGROUND

Osservatorio Nazionale sulla Sperimentazione Clinica dei Medicinali (OsSC) Agenzia Italiana del Farmaco (AIFA) Numero EudraCT 2007-004946-34.

Nationwide surveys of acute liver failure (ALF) are conducted annually in Japan, and 20% of patients with ALF undergo liver transplantation (LT). We extracted data for 212 patients who underwent LT for ALF from the nationwide survey database of the Intractable Liver Diseases Study Group of Japan. After the exclusion of 3 patients who underwent deceased donor LT, 209 recipients of living donor liver transplantation (LDLT) were analyzed. ALF patients were placed into 3 subgroups according to the time from the onset of the disease to the occurrence of encephalopathy: patients who presented with encephalopathy within 10 days of the disease's onset were classified as having acute ALF, patients who presented within 11 to 56 days were classified as having subacute ALF, and patients who presented within 9 to 24 weeks were classified as having late-onset hepatic failure (LOHF). Long-term follow-up data were obtained from the registry of the Japanese Liver Transplantation Society. The 2 data sets were merged, and descriptive and survival data were analyzed. A Cox regression analysis was performed to define factors predicting overall mortality, short-term mortality (≤90 days after LT), and long-term mortality (>90 days after LT). One hundred ninety of the analyzed patients (91%) were adults (age ≥ 18 years); 70 patients (34%) were diagnosed with acute ALF, 124 (59%) were diagnosed with subacute ALF, and 15 (7%) were diagnosed with LOHF. Hepatitis B virus was the most common cause of acute ALF (61%), whereas autoimmune hepatitis (14%) and drug allergy-induced hepatitis (14%) were more frequent in patients with subacute ALF or LOHF. The cumulative patient survival rates 1, 5, and 10 years after LT were 79%, 74%, and 73%, respectively. Patient age was associated with short- and long-term mortality after LT, whereas ABO incompatibility affected short-term mortality, and donor age affected long-term mortality. In conclusion, the long-term outcomes of LDLT for ALF in this study were excellent, regardless of the etiology or classification. The majority of the donors were living donors. Increasing the deceased donor pool might be an urgent necessity.

<A<em>b</em>stractText>To examine the feasi<em>b</em>ility of using a computer tool for stratifying the severity of Coronavirus Disease 2019 (COVID-19) <em>b</em>ased on computed tomography (CT) images.</A<em>b</em>stractText><A<em>b</em>stractText>We retrospectively examined 44 confirmed COVID-19 cases. All cases were evaluated separately <em>b</em>y radiologists (visually) and through an in-house computer software. The degree of lesions was visually scored <em>b</em>y the radiologist, as follows, for each of the 5 lung lo<em>b</em>es: 0, no lesion present; 1, &<em>lt</em>;1/3 involvement; 2, >1/3 and &<em>lt</em>; 2/3 involvement; and 3, >2/3 involvement. Lesion density was assessed <em>b</em>ased on the proportion of ground-glass opacity (GGO), consolidation and fi<em>b</em>rosis of the lesions. The parameters o<em>b</em>tained using the computer tool included lung volume (mL), lesion volume (mL), lesion percentage (%), and mean lesion density (HU) of the whole lung, right lung, left lung, and each lo<em>b</em>e. The scores o<em>b</em>tained <em>b</em>y the radiologists and quantitative resu<em>lt</em>s generated <em>b</em>y the computer software were tested for correlation. A Chi-square test was used to test the consistency of radiologist- and computer-derived lesion percentage in the right/left lung, upper/lower lo<em>b</em>e, and each of the 5 lo<em>b</em>es.</A<em>b</em>stractText><p><div>(<em>b</em>)Resu<em>lt</em></<em>b</em>)</div>The resu<em>lt</em>s showed a strong to moderate correlation <em>b</em>etween lesion percentage scores o<em>b</em>tained <em>b</em>y radiologists and the computer software (<i>r</i> ranged from 0.7679 to 0.8373, <i>P</i> &<em>lt</em>; 0.05), and a moderate correlation <em>b</em>etween the proportion of GGO and mean lesion density (<i>r</i> = -0.5894, <i>P</i> &<em>lt</em>; 0.05), and proportion of consolidation and mean lesion density (<i>r</i> = 0.6282, <i>P</i> &<em>lt</em>; 0.05). Computer-aided quantification showed a statistical significant higher lesion percentage for lower lo<em>b</em>es than that assessed <em>b</em>y the radiologists (χ² = 8.160, <i>P</i> = 0.004).</p><A<em>b</em>stractText>Our experiments demonstrated that the computer tool could relia<em>b</em>ly and accurately assess the severity and distri<em>b</em>ution of pneumonia on CT scans.</A<em>b</em>stractText>

The small genome of polyomaviruses encodes a limited number of proteins that are highly dependent on interactions with host cell proteins for efficient viral replication. The SV40 large T antigen (LT) contains several discrete functional domains including the LXCXE or RB-binding motif, the DNA binding and helicase domains that contribute to the viral life cycle. In addition, the LT C-terminal region contains the host range and adenovirus helper functions required for lytic infection in certain restrictive cell types. To understand how LT affects the host cell to facilitate viral replication, we expressed full-length or functional domains of LT in cells, identified interacting host proteins and carried out expression profiling. LT perturbed the expression of p53 target genes and subsets of cell-cycle dependent genes regulated by the DREAM and the B-Myb-MuvB complexes. Affinity purification of LT followed by mass spectrometry revealed a specific interaction between the LT C-terminal region and FAM111A, a previously uncharacterized protein. Depletion of FAM111A recapitulated the effects of heterologous expression of the LT C-terminal region, including increased viral gene expression and lytic infection of SV40 host range mutants and adenovirus replication in restrictive cells. FAM111A functions as a host range restriction factor that is specifically targeted by SV40 LT.

Pseudomonas aeruginosa is a leading cause of hospital-acquired infections and is resistant to many antibiotics. Among its primary mechanisms of resistance is expression of a chromosomally encoded AmpC β-lactamase that inactivates β-lactams. The mechanisms leading to AmpC expression in P. aeruginosa remain incompletely understood but are intricately linked to cell wall metabolism. To better understand the roles of peptidoglycan-active enzymes in AmpC expression-and consequent β-lactam resistance-a phenotypic screen of P. aeruginosa mutants lacking such enzymes was performed. Mutants lacking one of four lytic transglycosylases (LTs) or the nonessential penicillin-binding protein PBP4 (dacB) had altered β-lactam resistance. mltF and slt mutants with reduced β-lactam resistance were designated WIMPs (wall-impaired mutant phenotypes), while highly resistant dacB, sltB1, and mltB mutants were designated HARMs (high-level AmpC resistant mutants). Double mutants lacking dacB and sltB1 had extreme piperacillin resistance (>256 μg/ml) compared to either of the single knockouts (64 μg/ml for a dacB mutant and 12 μg/ml for an sltB1 mutant). Inactivation of ampC reverted these mutants to wild-type susceptibility, confirming that AmpC expression underlies resistance. dacB mutants had constitutively elevated AmpC expression, but the LT mutants had wild-type levels of AmpC in the absence of antibiotic exposure. These data suggest that there are at least two different pathways leading to AmpC expression in P. aeruginosa and that their simultaneous activation leads to extreme β-lactam resistance.

BACKGROUND

Vitamin D may act as an immune modulator in experimental and human organ transplantation, but these data are yet to be confirmed in human liver transplantation (LT).

OBJECTIVE

This study aimed to assess the relationship between acute liver allograft cellular rejection (ACR) and pretransplant serum vitamin D concentration or post-transplant vitamin D supplementation.

METHODS

We studied 133 LT recipients who underwent two per protocol allograft biopsies in the early post-operative period, plus on-demand biopsies as clinically indicated. ACR estimate was given according to the Banff scheme in biopsies obtained along two follow-up periods: (a) from the transplant operation to the end of the second month (0-2 months); (b) and from the third month to the end of the eighth month (3-8 months) post-LT.

RESULTS

The median pretransplant serum 25-hydroxyvitamin D concentration was 12.5 ng/ml; 40 patients had concentrations < or =12.5 ng/ml, of whom six had < or =5.0 ng/ml. Seventy-nine recipients received oral vitamin D(3) supplementation to treat post-transplant osteoporosis. In the 0-2 months period, moderate-to-severe rejection episodes were independently associated with cytomegalovirus reactivation (P<0.005) and progressively lower pretransplant serum 25-hydroxyvitamin D concentrations (P<0.02). Early vitamin D(3) supplementation was independently associated with a lack of ACR (P<0.05).

CONCLUSIONS

These results suggest that vitamin D may favour immune tolerance towards the liver allograft.

It is commonly believed that allergic sensitization starts when an allergen contacts the surface of an antigen-presenting cell in mucosal or skin epithelia. Most studies dealing with this aspect use allergen extracts as stimulus. Under natural exposure conditions, however, the bioavailability of allergen depends on allergen liberation from internal binding sites within the allergen carrier, e.g. pollen grains. In comparing total protein and major allergen release from timothy grass (Phleum pratense L.) pollen freshly collected on rural meadows or near high-traffic roads, there was a striking difference between the pollen, with higher allergen release rates from rural meadow pollen grains. Thus, allergen release does not explain the higher prevalence rates of atopic sensitization and disease observed in many epidemiological studies in children exposed to automobile exhaust. Therefore, other possible effectors from pollen grains were investigated. Pollen grains incubated in protein- free buffer were found to secrete significant amounts of eicosanoid-like substances, namely leukotriene (LT) B(4)-like and prostaglandin E(2)-like substances, in a pH-, time- and temperature-dependent fashion. The highest values of eicosanoid secretion were found in birch, grass and mugwort pollen, while pine (Pinus sylvestris L.) pollen showed only marginal eicosanoid-like secretion. Additionally, the release of these substances was significantly higher from pollen which had been collected near roads with heavy traffic, indicating a stronger proinflammatory activity of these pollen grains. In order to investigate the effects of air pollutants, native pollen grains were exposed in a dose- and time-dependent fashion in a fluidized bed reactor to traffic-related pollutants, e.g. volatile organic compounds (toluene, m-xylene), leading again to a significant increase in the secretion of LTB(4)-like immunoreactivity, in contrast to exposure with sulfur dioxide. This finding opens a new dimension of understanding of the early events in allergic sensitization, indicating that proinflammatory effects of the allergen carrier, e.g. the pollen grain itself, can lead to activation of the mucosal membrane. These findings might help to also explain the higher prevalence rates of pollen allergy in areas with high automobile exhaust emissions. Furthermore, the allergenic 'potency' of various allergens has to be redefined at the allergen carrier level with regard to different stages of allergen and mediator release prior to the contact with the host's immune system.

The heat-labile enterotoxin of Escherichia coli (LT) consists of an enzymatically active A subunit (LTA) and a pentameric B subunit (LTB). LT has been extensively studied as a potent modulator of immune responses but wild-type LT is toxic and therefore unsuitable for clinical use. Approaches pursued to avoid the toxicity associated with the use of the native toxin while retaining its adjuvant properties have included isolation of subunit B (LTB) and construction of non-toxic LT AB complex mutants, such as LTK63 mutant. Here we review the immunomodulatory characteristics of LTB and LTK63 and their potential as mucosal and parenteral vaccine adjuvants.