Granzyme B: an essential protease for the inflammatory response

BACKGROUND: The study reported here was performed to investigate morphologic intraocular reactions on the surface of metallic intraocular foreign bodies (IOFB) with scanning electron microscopy. METHODS: Twenty-seven extracted IOFB were investigated. Of these, 22 were situated in the vitreous body; 19 had contact with the retina. Five IOFB had been removed from the anterior segment (control group). The duration of intraocular retention was 6 h to 24 days. Immediately after microsurgical removal the IOFB were fixed, dehydrated, dried, sputter-coated and investigated with a scanning electron microscope. Two IOFB from the vitreous were treated for collagen preservation. RESULTS: Eighteen of 20 intravitreal IOFB showed fibers of fibrin on its surface; 11 of 20 were covered with a homogeneous layer. Within this layer a net of collagen fibers was detectable. A major cellular reaction was observed only on IOFB that injured the retina, pigment epithelium and choroid. CONCLUSIONS: This morphologic study shows that: (1) a fibrin net develops in the vitreous around intravitreal IOFB; (2) depositions of amorphous material into the spaces of this net lead to dense coverage of the IOFB; (3) cellular reactions are not condition for the development of this coverage; (4) laceration of the retina induces a fibrocellular response.     

Rapid response: care of burn victims

1. The occupational health nurse must understand the prehospital principles for treatment of burn victims. This understanding promotes appropriate burn management which can impact mortality and morbidity. 2. The most important concept in emergency management of burn victims is scene safety, the nurse's safety, and ultimately, the victim's safety. 3. All burn victims need to be managed as trauma victims with a primary and secondary survey to rapidly determine life threatening problems and whether other injuries are present. 4. Familiarity with the structures and functions of the skin is imperative to understand the pathophysiology and consequences of burn injuries.     

Intravenous zymosan-A challenge induces an alveolar inflammatory response

The purpose of this study was to evaluate the ability of intravenous zymosan-A (ZyA) challenge to induce an alveolar inflammatory response as indicated by inflammatory changes among lung lavage cells. The organ distribution of 1 mg of [51Cr]ZyA revealed that immediately following intravenous challenge of female ICR mice approximately 81% of the total cpm injected was associated with pulmonary tissue. Approximately 15% of the injected cpm was associated with the peripheral blood, liver, and spleen. ZyA translocated from the vascular compartment into pulmonary alveoli and was detected within polymorphonuclear neutrophils (PMN) and alveolar macrophages (AM) 18 h after intravenous challenge. PMN numbers among lung lavage cells increased beginning one day after challenge to a peak of approximately 5 x 10(5) PMNs by day 3 after challenge. The PMN response subsided by day 5 after challenge. There was no significant increase in the numbers of AM during the first week after intravenous ZyA; however, the number of AM increased from approximately 5 x 10(5) AM on day 1 after challenge to approximately 1.1 x 10(6) AM by day 5 after challenge. Within 24 h of intravenous ZyA, the number of AM in S phase of the cell cycle increased from approximately 2.5 x 10(4) AM one day after challenge to 1.1 x 10(5) AM in S phase five days after challenge. The data suggest that intravenous ZyA localized within pulmonary tissue immediately following intravenous challenge and translocated into the alveolar compartment where ZyA particles were found within phagocytes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Postoperative inflammatory response after autologous and allogeneic blood transfusion

BACKGROUND: Allogeneic blood transfusions cause immunosuppression. The aim of this study was to determine whether complement anaphylatoxins, cytokines, or both are released in the recipient, after blood transfusions in general, and after autologous blood transfusions in particular. METHODS: Thirty-one patients having total hip joint replacement surgery were randomized to receive either allogeneic red blood cells (n = 15) or predeposited autologous whole blood transfusion (n = 16). Plasma concentrations of the anaphylatoxins C3a and C5a, the terminal C5b-9 complement complex, and cytokines IL-6 and IL-8 in the recipients were repeatedly analyzed before, during, and after surgery. RESULTS: Significantly increased concentrations of IL-6 and IL-8 appeared in both groups, with a significantly greater increase in the autologous blood group. Patients in both groups developed a moderate but significant increase of C3a without a significant difference between them. C5a and terminal C5b-9 complement complex were not greatly changed. CONCLUSIONS: The study showed a greater increase in cytokine concentration after autologous blood transfusion than after allogeneic blood transfusion. The lower response in the latter may result from transfusion-induced suppression of cellular immunity.     

Brain inflammatory response induced by intracerebroventricular infusion of lipopolysaccharide: an immunohistochemical study

Turkey meningoencephalitis virus (TMEV) causes paralysis and mortality in turkeys. Because the classical diagnostic methods are complicated, we developed the RT-PCR as a new molecular diagnostic method. Since the nucleic acid sequence of TMEV is unknown, the first step in developing the RT-PCR relied on conserved sequences of viruses belonging to the Flaviviridae family, in which TMEV has been classified serologically. Using primers from the NS5 gene, three amplification products of TMEV RNA were obtained (125 bp, 181 bp and 800 bp). Their sequences were homologous to one another and to the NS5 gene of other flaviviruses.     

Exacerbation of the inflammatory response to Mycobacterium tuberculosis after antiretroviral therapy

A patient with HIV infection was successfully treated for pulmonary tuberculosis, but pulmonary inflammation and lymphadenitis worsened dramatically after subsequent combination antiretroviral therapy. As this relapse coincided with development of a strong delayed-type hypersensitivity response to tuberculin and improved after treatment with the anti-inflammatory agent oxpentifylline, it was probably caused by restoration of pathogen-specific cellular immunity.     

Passive avoidance behavior in rats after electroconvulsive shock: Facilitative effect of response retardation.

In 3 experiments, a total of 178 male Wistar rats were trained in a one-trial passive avoidance task and then were submitted to electroconvulsive shock (ECS) or to sham ECS. 24 hrs later they were tested for retention, with the door opened either immediately or 30 sec after the beginning of the test. Ss initially forced to avoid for 30 sec continued to avoid for the entire test, but the others had the usual low step-through latencies seen with ECS-treated Ss. Activity measures for those Ss stepping through differentiated groups having received footshock from those not having footshock and ECS. A retest 5-10 min later showed "recovery" in the amnestic Ss and continued avoidance behavior for those that avoided on the first test. Results are taken as evidence that ECS effects are not on memory storage but on the capacity of the animal to organize information effectively and quickly in order to produce an adaptive response. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

PET validation of a novel prefrontal task: Delayed response alteration.

Deficits in working memory have been proposed to explain the performance failures of frontally lesioned primates on delayed alternation (DA) and delayed response (DR) tasks. The authors examined a computerized test of delayed response alternation (DRA), which combines elements of DR and DA in a sample of 18 normal volunteers who underwent oxygen-15 PET regional cerebral blood flow scans during the DRA and a sensorimotor control task. Significant activations were observed in a network of frontal, parietal, occipital, and temporal regions during initial task performance. A qualitatively similar but somewhat reduced set of activations was observed in a subset of participants who repeated the task after practice and instruction. These results are consistent with distributed models of working memory derived from studies of nonhuman primates and suggest that the frontal lobes contribute to human working memory function. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cue and response-choice acquisition and reversal after exposure to uncontrollable shock: Induction of response perseveration.

Evaluated the effects of inescapable shock in shock-motivated cue, response-choice (RC), and RC/positional Y-maze discrimination tasks. Ss were 253 male CD-1 mice. In the RC paradigm, Ss were required to turn in a predetermined direction to escape, whereas in the RC/positional task, Ss were required to enter the arm to the right of the start arm on any given trial. Although inescapable shock retarded escape performance, this was dependent on task difficulty and on the compatibility between response tendencies and the response requirement of the task. Irrespective of the task, exposure to inescapable shock did not influence accuracy of discrimination responding (acquisition or performance of a previously established discrimination). Likewise, discrimination reversal performance was unaffected by inescapable shock in either the cue or the RC paradigm. In contrast, acquisition of the RC/positional reversal was retarded by inescapable but not escapable shock. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dual control of heat shock response: involvement of a constitutive heat shock element-binding factor

Heat shock factor (HSF) has been implicated as the key regulatory protein in the heat shock response. Our studies on the response of rodent cells to heat shock or sodium arsenite indicate that a high level of HSF-DNA-binding activity, by itself, is not sufficient for the induction of hsp70 mRNA synthesis; furthermore, a high level of HSF binding is also not necessary for this induction. Analysis of the binding of protein factors to the heat shock element (HSE) in extracts of stressed rodent cells indicates that the regulation of heat shock response involves the heat-inducible HSF and a constitutive HSE-binding factor. Our results also suggest that overexpression of human hsp70 may decrease the level of heat-induced HSF-HSE-binding activity in rat cells.     

Mediators of septic shock: new approaches for interrupting the endogenous inflammatory cascade

OBJECTIVES: To review the molecular pathogenesis of septic shock, with particular emphasis on the induction of cytokines by endotoxin. By understanding the mechanisms that result in the systemic inflammatory response, novel clinical interventions may be more effectively studied. DATA SOURCES: The English medical literature was reviewed, including human clinical trials, animal experiments, and in vitro studies elucidating cellular and molecular interactions. Expert testimony from the Roundtable Conference on Sepsis (Brussels, March 1992) was also used to synthesize emerging concepts and to ensure inclusion of ongoing investigations. STUDY SELECTION: Emphasis on controlled experimental studies which elucidated the molecular and cellular interactions during sepsis. DATA EXTRACTION: This study focused only on data that directly involved the induction and regulation of protein mediators of sepsis, especially tumor necrosis factor (TNF) and interleukin-1. Data concerning the role of TNF during health were extracted from the author's peer-reviewed data. DATA SYNTHESIS: Information concerning the many facets of the systemic inflammatory response was integrated into a chronological, clinically oriented model of cytokine induction during endotoxemia. CONCLUSIONS: The induction of inflammation during sepsis is a complex, but increasingly understood, biological cascade that is dependent on inter- and intracellular signaling. Novel biotherapies may improve patient outcome in sepsis by interrupting any or all points of signal transduction.     

Heat shock proteins: regulators of stress response and apoptosis

Nup153 is a large O-linked glycoprotein that is a component of the basket-like structure that forms the nucleoplasmic face of nuclear pore complexes (NPCs). The Nup153 molecule has a tripartite structure consisting of N- and C-terminal domains flanking a central zinc finger domain. All of the targeting and assembly information contained within Nup153 is contributed by the N-domain. In fact this region of the molecule can target a cytosolic protein, pyruvate kinase, to the nucleoplasmic face of the NPC. The zinc finger and C-terminal domains appear to have no role in these targeting and assembly activities. Deletion analysis reveals that there are two distinct regions within the Nup153 N-domain that contain different targeting functions. One of these is directly involved in assembly into the NPC while a second overlapping region may target Nup153, as well as other reporter molecules, to the inner face of the nuclear envelope.     

RhoA signaling via serum response factor plays an obligatory role in myogenic differentiation

Serum response factor (SRF) plays a central role during myogenesis, being required for the expression of striated alpha-actin genes. As shown here, the small GTPase RhoA-dependent activation of SRF results in the expression of muscle-specific genes, thereby promoting myogenic differentiation in myoblast cell lines. Co-expression of activated V14-RhoA and SRF results in an approximately 10-fold activation of the skeletal alpha-actin promoter in replicating myoblasts, while SRFpm1, a dominant negative SRF mutant, blocks RhoA dependent skeletal alpha-actin promoter activity. Serum withdrawal further potentiates RhoA- and SRF-mediated activation of alpha-actin promoter to about 30-fold in differentiated myotubes. In addition, the proximal SRE1 in the skeletal alpha-actin promoter is sufficient to mediate RhoA signaling via SRF. Furthermore, SRFpm1 and to a lesser extent dominant negative N19-RhoA inhibit myoblast fusion, postreplicative myogenic differentiation, and expression of direct SRF targets such as skeletal alpha-actin and indirect targets such as myogenin and alpha-myosin heavy chain. Moreover, RhoA also stimulates the autoregulatable murine SRF gene promoter in myoblasts, and the expression level of SRF is reduced in myoblasts overexpressing N19-RhoA. Our study supports the concept that RhoA signaling via SRF serves as an obligatory muscle differentiation regulatory pathway.     

Experimental analysis of progressive necrosis after spinal cord trauma in the rat: etiological role of the inflammatory response

Progressive tissue necrosis is a unique reaction to spinal cord trauma in which the site of injury is gradually transformed into a large, cavity-filled lesion. The earliest histopathological changes after injury include a widely disseminated extravasation of erythrocytes and neutrophils. To test whether such an inflammatory reaction might initiate progressive necrosis, we examined the effects of the following anti-inflammatory treatments: allopurinol (Ap) to inhibit injury-induced xanthine oxidase, indomethacin (I) or naproxen to inhibit constitutive and inducible cyclooxygenase, aminoguanidine (Ag) to inhibit inducible nitric oxide synthase, pregnenolone (P) as a precursor steroid, and a bacterial lipopolysaccharide (L) to stimulate secretory activities of glial cells and macrophages. The spinal cord of adult rats was crushed at T8 with jeweler's forceps and, after 3 or 21 days of treatment, the cords were studied quantitatively by light microscopical image analysis. Ag, Ag+I, or Ap significantly reduced the size of the primary lesion at 3 days postoperatively, while P+L+I did so only after 21 days of treatment. A secondary lesion developed in the dorsal column and gradually extended for many millimeters rostral and caudal from the primary lesion. The size of the dorsal column lesion was diminished by 3-day treatment with Ap and by 21-day treatment with Ap or P+L+I, but Ag or Ag+I had no effect. We conclude that (a) progressive necrosis is initiated and maintained by inflammatory mechanisms and (b) for this reason, treatment with specific anti-inflammatory agents selectively attenuates various components of the necrotizing process.     

Effect of the antioxidant Nicanartine on the proliferative and inflammatory response after experimental balloon angioplasty

BACKGROUND: Antioxidant treatment seems to reduce the development of restenosis after percutaneous transluminal angioplasty. In this study, the effect of Nicanartine, a new antioxidant drug with both antiproliferative and lipid-lowering properties, on the proliferative and inflammatory response after balloon angioplasty was investigated in a rabbit model of restenosis. METHODS: To induce pre-interventional plaques in the common carotid artery of 48 New Zealand White rabbits, electrostimulation was carried out for 28 days. After a break of 7 days, balloon angioplasty was performed in 36 animals, of which 18 received Nicanartine at a dose of 120 mg/kg body weight; the other 18 served as a control group. The vessels were excised by day 7 and 28 after balloon angioplasty and examined for intimal plaque size, macrophage content and proliferative activity. Bromodeoxyuridine labeling was used to determine proliferating cells in the dilated segment; macrophages were detected using the RAM-11 antibody. RESULTS: In the Nicanartine-treated group, immunohistological quantification 7 days after intervention showed a statistically significant (P< 0.05) reduction of both cells undergoing DNA synthesis (1.6+/-1.4% versus 3.7+/-2.2%) and intimal macrophages (0.7+/-1.2% versus 1.3+/-0.6%). Twenty-eight days after balloon angioplasty, proliferative activity in both groups was decreased to a level comparable to the non-dilated control groups. A clear trend towards smaller plaques could be seen in the Nicanartine group (0.146+/-0.077 mm2 versus 0.255+/-0.174 mm2). Total cholesterol levels did not differ significantly between the groups. CONCLUSION: Under treatment with Nicanartine a clear reduction in the proliferative and inflammatory response after balloon angioplasty was observed. Antioxidant treatment, especially with compounds having antiproliferative and lipid-lowering properties, appears to be an effective secondary preventive strategy after interventional treatment in patients with coronary artery disease.     

Interleukin-1 mediates a rapid inflammatory response after injection of adenoviral vectors into the brain

Adenovirus-mediated gene transfer into the brain is associated with significant inflammation and activation of anti-vector and anti-transgene immune responses that curtail the gene delivery of adenoviruses and therapeutic efficacy. Elucidating the molecular mediators of inflammatory and immune responses to adenoviruses injected into the brain should allow us to inhibit their inflammatory actions, thereby reducing vector clearance and enhance adenoviral-mediated gene transfer into the CNS. Cytokines are primary mediators of the immune response and are released during inflammation. Here we report for the first time that injection of replication-deficient adenovirus vectors into the cerebral ventricles of rats causes a rapid increase in body temperature. This fever response precedes any vector-encoded transgene expression and occurs with vectors encoding no transgene, as well as with vectors encoding a therapeutic transgene i.e., HSV1-thymidine kinase. No fever is detected after infection of the striatum, an important brain target in studies on neurodegeneration. After infection of the brain ventricles, CSF levels of immunoreactive tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta increase significantly (up to 300-fold). In the hypothalamus, the locus of thermoregulation in the brain, only IL-1beta and IL-6 are significantly elevated. A neutralizing TNF-alpha antibody has no effect on adenovirus-induced fever. However, pretreatment with either the IL-1 receptor antagonist or the cyclooxygenase inhibitor flurbiprofen completely abolishes adenovirus-induced fever, suggesting that IL-1 and prostaglandins are direct mediators of this response. These results are the first to demonstrate that IL-1, but not TNF-alpha, is the main mediator of a very early inflammatory response to adenovirus in the brain.