Involvement of p38 mitogen-activated protein kinase in the induction of tolerance to hemorrhagic and endotoxic shock.

BACKGROUND: Exposure to sublethal hemorrhage (SLH) makes rats tolerant to subsequent hemorrhagic or septic shock and is associated with altered NF-kappaB activity. The purpose of this study was to explore whether changes in p38 mitogen-activated protein (MAP) kinase activity also occur in the induction of tolerance by SLH. METHODS: Rats were made tolerant by SLH or sham operation. Twenty-four hours later rats were exposed to lipopolysaccharide (LPS) or had peritoneal macrophages (Mphi) isolated. CNI-1493, a p38 MAP kinase inhibitor, or saline was given prior to SLH. Lungs were harvested 1 h after SLH or LPS and total protein was extracted. Peritoneal Mphi were stimulated with LPS (10 microg/ml) and total protein was isolated 1 h later. Active, dually phosphorylated p38 MAP kinase was determined by Western blot. Tumor necrosis factor (TNF) was measured in Mphi supernatants by enzyme-linked immunosorbent assay (ELISA) 18 h after LPS. RESULTS: SLH activated p38 MAP kinase in the lung and this was inhibited by CNI-1493. Twenty-four hours later, lung p38 MAP kinase activity increased to the same degree in tolerant and sham rats following LPS, but much more prominently in the CNI-1493 treated rats. There was no p38 activity in peritoneal Mphi at baseline, and similar to lung p38, LPS led to increased p38 activity which was most significant in Mphi from rats that received CNI-1493 prior to SLH. TNF production by tolerant Mphi in response to LPS was significantly (P < 0.05, t test) decreased and p38 inhibition with CNI-1493 at the time of SLH reversed the inhibitory effects of tolerance on TNF production. CONCLUSIONS: TNF production by tolerant Mphi following a second insult (LPS) is attenuated despite preservation of normal p38 MAP kinase activity. However, activation of this intracellular second messenger is a necessary step in the "cellular reprogramming" that occurs during the induction of tolerance by SLH.

Renal ischemia/reperfusion leads to macrophage-mediated increase in pulmonary vascular permeability.

BACKGROUND: Despite the advent of dialysis, survival with acute renal failure when associated with multiorgan failure is poor. The development of lung injury after shock or visceral ischemia has been shown; however, the effects of isolated renal ischemia/reperfusion injury (IRI) on the lungs are unclear. We hypothesized that isolated renal IRI could alter pulmonary vascular permeability (PVP) and that macrophages could be important mediators in this response. METHODS: Rats (N = 5 per group) underwent renal ischemia for 30 minutes, followed by reperfusion. Lung vascular permeability was evaluated by quantitation of Evans blue dye extravasation from vascular space to lung parenchyma at 1, 24, 48, or 96 hours after reperfusion. Serum was collected for blood urea nitrogen and creatinine at each time point. To examine the role of the macrophage, the macrophage pacifant CNI-1493, which inhibits the release of macrophage-derived inflammatory products, was administered in a blinded fashion during renal IRI. RESULTS: PVP was significantly (P < 0.05) increased at 24 hours and peaked at 48 hours after IRI compared with shams as well as baseline levels. PVP after IRI became similar to shams after 96 hours. This correlated with increases in blood urea nitrogen and creatinine at similar time points. At 48 hours, CNI-1493 significantly abrogated the increase in PVP compared with IRI alone. However, CNI-1493 did not alter the course of the acute renal failure. Pulmonary histology demonstrated interstitial edema, alveolar hemorrhage, and red blood cell sludging after renal IRI, which was partially attenuated by CNI-1493. CONCLUSIONS: Increased PVP develops after isolated renal IRI, and macrophage-derived products are mediators in this response. These findings have implications for understanding the mechanisms underlying respiratory dysfunction associated with acute renal failure.

Tolerance to shock: an exploration of mechanism.

OBJECTIVE: To determine if cross-tolerance to septic shock could be induced by a previous insult with sublethal hemorrhage (SLH) and to characterize the mechanisms involved in this induced protective response. BACKGROUND DATA: It is possible to condition animals by prior SLH such that they tolerate an otherwise lethal hemorrhage. It is also possible to condition animals with low doses of lipopolysaccharide (LPS) so that they survive a "lethal" septic insult. However, a paucity of information exists on cross-tolerance between hemorrhage and sepsis. METHODS: Rats were made tolerant by conditioning SLH or sham operation. Twenty-four hours later, tolerant and sham rats were exposed to a lethal dose of LPS. To explore the mechanism of tolerance induction, rats were given the macrophage (Mphi) inhibitor CNI-1493 or saline carrier before SLH. Survival and pulmonary vascular injury were determined after LPS. Serum tumor necrosis factor (TNF) levels and splenic Mphi TNF gene expression were measured at several time points. RESULTS: Prior SLH indeed made rats tolerant and imparted a significant survival benefit and reduction in pulmonary vascular injury after LPS. The tolerance induced by SLH was reversed by Mphi inhibition. Tolerant animals had low serum TNF levels immediately after SLH and reduced circulating TNF levels after LPS. SLH, however, did not inhibit the augmentation of TNF gene expression after LPS. CONCLUSIONS: Sublethal hemorrhage bestows protection against a lethal LPS challenge. Inhibition of the Mphi attenuated the benefit of the tolerance induced by SLH. Circulating TNF but not TNF gene after LPS is lessened by SLH. This implicates changes in Mphi intracellular signaling in induction of the tolerant state.

Induction of tolerance to hemorrhagic or endotoxic shock involves activation of NF-kappaB.

BACKGROUND: Tolerance to hemorrhagic or endotoxic shock can be induced by prior sublethal hemorrhage (SLH). The purpose of this study was to explore whether alterations in signal transduction pathways involving NF-kappaB occur in macrophages (Mphi) following induction of tolerance by SLH. METHODS: Using a model of SLH previously shown in our lab to impart a survival benefit to subsequent hemorrhagic or endotoxic shock, rats (n = 30) were conditioned by SLH. Peritoneal Mphi were harvested 24 h after conditioning and stimulated with lipopolysaccharide (LPS) (10 microg/mL). Nuclear and cytosolic proteins were isolated 1 h later for determination of NF-kappaB activation by gel-shift assay and IkappaB-alpha by Western blot. TNF mRNA gene expression was measured 4 h after LPS stimulation by reverse transcription/polymerase chain reaction (RT/PCR). TNF protein levels were measured in cellular supernatants by enzyme-linked immunosorbent assay (ELISA) 18 h after LPS. RESULTS. LPS stimulation of sham Mphi increased NF-kappaB activation with corresponding loss of its inhibitor IkappaB-alpha. In contrast, IkappaB-alpha was not detectable following conditioning, and conditioned Mphi had NF-kappaB activation at baseline which increased minimally with LPS stimulation. LPS increased TNF gene expression and significantly increased protein production by both sham and conditioned Mphi, but this increase was greater in the sham-conditioned group. CONCLUSIONS: The ability of Mphi from animals made tolerant by SLH to produce TNF in vitro is conserved. Nevertheless, these same Mphi exhibit alterations in TNF gene induction and expression as well as signal transduction, specifically, changes in IkappaB-alpha and NF-kappaB activation. This suggests a role for activation of NF-kappaB in the induction of tolerance.

Sublethal hemorrhage blunts the inflammatory cytokine response to endotoxin in a rat model.

BACKGROUND: Tolerance to lipopolysaccharide (LPS) induced by previous hemorrhage in mice is associated with a blunted interleukin 1 (IL-1) response, suggesting down-regulation of the cytokine cascade as a possible protective mechanism. This study was undertaken to determine whether prehemorrhage induces attenuation of the cytokine response to sepsis beyond IL-1 in a rat model and whether this response occurs at the level of gene transcription. METHODS: Sprague-Dawley rats underwent sublethal hemorrhage, lethal intraperitoneal endotoxin, or sublethal hemorrhage with delayed lethal endotoxin. Animals were killed 12 hours after LPS injection or 24 hours after hemorrhage. IL-1 and tumor necrosis factor (TNF) mRNA levels were determined on total splenic RNA using reverse-transcriptase polymerase chain reaction, and serum cytokine levels were determined using enzyme-linked immunosorbent assay. RESULTS: Animals that received LPS alone mounted an IL-1 and TNF response (RNA and protein) much higher than animals subjected to hemorrhage alone. TNF and IL-1 gene expression and protein levels in prehemorrhaged animals that received LPS, however, were significantly lower than those of animals that received LPS alone. CONCLUSION: Hemorrhage induces early IL-1 and TNF gene expression, which blunts their subsequent expected increase after endotoxic challenge. These findings validate previously documented immune-modulated protective effects of the first insult in a two-hit model.

Respiratory syncytial virus immune globulin for prophylaxis against respiratory syncytial virus disease in infants and children with congenital heart disease. The Cardiac Study Group.

OBJECTIVE: To examine the effectiveness of respiratory syncytial virus immune globulin administered intravenously (RSV-IGIV) in reducing hospitalization for treatment of RSV in children with congenital heart disease (CHD). METHODS: Children younger than 4 years of age were randomly assigned to a treatment group receiving RSV-IGIV, 750 mg/kg, monthly or to a control group not receiving infusions. Surveillance for respiratory tract infections was carried out and management decisions were made by physicians blinded to treatment group. RESULTS: Hospitalization for treatment of an RSV infection occurred in 32 of 214 (15%) of control children and 21 of 202 (10%) of the children receiving RSV-IGIV, a 31% reduction (P = .16). However, in infants younger than 6 months of age at study entry, 20 of 82 (24%) in the control group and 10 of 96 (10%) in the RSV-IGIV group had RSV hospitalizations (58% reduction, P = .01). The incidence of hospitalization for any respiratory tract symptomatology was lower in the RSV-IGIV group (34 of 202, 17%) than in the control group (57 of 214, 27%; P = .02). There was a significantly higher frequency of unanticipated cyanotic episodes and of poor outcomes after surgery among children with cyanotic CHD in the RSV-IGIV group (22 of 78, 28%) than in the control group (4 of 47, 8.5%; P = .009). CONCLUSION: RSV-IGIV should not be used for prophylaxis of RSV disease in children with cyanotic CHD. RSV-IGIV did not reduce RSV hospitalization in all children with CHD, but it was effective in preventing RSV hospitalization in infants younger than 6 months of age. Further studies in these children are indicated.

The physiologic consequences of macrophage pacification during severe acute pancreatitis.

Macrophage overproduction of inflammatory mediators is detrimental in the progression of acute pancreatitis. Although inhibition of inflammatory mediators has been shown to decrease the severity of experimental pancreatitis and improve overall survival, less is known about the mechanism by which blockade produces these benefits. Prior to the induction of lethal acute pancreatitis, rats were randomized to receive a single dose (.01, .1, 1.0, or 10 mg/kg) of a macrophage-pacifying compound (CNI-1493) or vehicle. Escalating doses provided incremental increases in survival from 10% (vehicle) to a maximum of 70% (CNI-1493, 1.0 mg/kg). To evaluate the physiologic mechanism responsible for the improved survival, continuous arterial blood pressure, serial hematocrit, ascites volume, pancreatic edema, bronchoalveolar leukocytes and protein, and pancreatic histology were determined in additional rats receiving CNI-1493 (1.0 mg/kg). Serum tumor necrosis factor-alpha and nitrites were also determined to assess the mechanism of action of CNI-1493. Macrophage pacification decreased pancreatitis severity as determined by enzyme release and pancreatic histology score. Ascites volume and bronchoalveolar protein levels were also decreased, indicating that CNI-1493 prevents the loss of circulating blood volume and maintains hematocrit and mean arterial pressure, thus improving survival. CNI-1493 prevented the increase of serum tumor necrosis factor-alpha but not serum nitrites, implicating macrophage-derived cytokines and not nitric oxide in the pathogenesis of physiologic decompensation and death in this model of pancreatitis.

Respiratory syncytial virus (RSV) immune globulin intravenous therapy for RSV lower respiratory tract infection in infants and young children at high risk for severe RSV infections: Respiratory Syncytial Virus Immune Globulin Study Group.

OBJECTIVES: To evaluate the efficacy of high-titer intravenous respiratory syncytial virus immune globulin (RSVIG) in the treatment of children at high risk for severe RSV infection who were hospitalized with proven RSV. METHODS: Infants and young children younger than 2 years with bronchopulmonary dysplasia, chronic lung disease, congenital heart disease, or prematurity (<32 weeks' gestational age), hospitalized with a history of lower respiratory tract infection (LRI) of less than 4 days, were enrolled in this study. Patients were randomized in a blinded fashion to receive either 1500 mg/kg RSVIG or placebo in equal volumes. They were evaluated daily for safety and respiratory scores and for RSV nasal shedding. RESULTS: One hundred seven high-risk children were randomized--54 in the RSVIG group and 53 in the placebo group. Of these children, 51 in each group were considered evaluable. Children with pulmonary disease, congenital heart disease, or prematurity were equally distributed between the two treatment groups. However, two important differences were found in baseline variables between the two groups: there were more patients in the placebo group who had histories of previous LRI and there was a trend toward more severe disease at study entry in the RSVIG group. This was manifested by a higher entry respiratory score in the RSVIG group than in the placebo group (3.4 +/- 0.2 vs 3.1 +/- .01). A higher proportion of children in the RSVIG group (47%) than in the placebo group (28%) required intensive care at entry and mechanical ventilation at study entry (31% RSVIG-treated vs 18% placebo-treated patients). No significant difference was found between groups in the mean unadjusted duration of hospitalization (RSVIG group, 9.10 +/- 1.18 days; control group, 8.17 +/- 1.08 days). When the mean was adjusted for entry respiratory score, likewise, no difference was observed between each group (8.41 +/- 0.97 vs 8.89 +/- .99 days). The lack of efficacy observed in the study primary endpoint was observed in all diagnostic groups. No differences between the RSVIG and placebo groups were observed in the following secondary endpoints: duration of intensive care unit stay, duration of intensive care unit stay for RSV, mechanical ventilation, or supplemental oxygen. No significant differences in adverse events were reported in the RSVIG group (16 children) when compared with the control group (10 children). CONCLUSION: RSVIG treatment was safe but not efficacious in the treatment of children with bronchopulmonary dysplasia, congenital heart disease, or premature gestation who were hospitalized with RSV LRI.

Safety and bioequivalency of three formulations of respiratory syncytial virus-enriched immunoglobulin.

Respiratory syncytial virus (RSV) causes serious illness (lower respiratory illness) in preterm infants. RSV antibody-enriched immunoglobulin (RSVIG) that was lyophilized (LYO) protected against RSV lower respiratory illness. The Food and Drug Administration now requires an additional viral inactivation step (VI). We compared LYO, LYO-VI, and a more convenient liquid RSVIG (LIQ-VI) in 30 preterm infants (median age, 7 months; median weight, 5.4 kg). Infants were randomized to receive LYO (n = 10), LYO-VI (n = 10), or LIQ-VI (n = 10) in monthly infusions of 750 mg/kg of body weight per dose (December to March). Children were monitored closely for adverse reactions to RSVIG and for RSV illness.

Virus-specific antibody responses to human cytomegalovirus (HCMV) in human immunodeficiency virus type 1-infected persons with HCMV retinitis.

Human cytomegalovirus (HCMV) causes retinitis and is the leading cause of blindness in patients infected with the human immunodeficiency virus (HIV). While most patients with HIV are HCMV seropositive, not all will develop clinical complications from it. The immune responses that can prevent the development of HCMV retinitis are unknown. The levels of anti-HCMV antibodies, including responses to the two major envelope proteins, gpUL55 (gB) and gpUL75 (gH), which are the targets of neutralizing antibody (NA), were examined in HIV-infected patients with and without retinitis. No specific deficiency in the antibody response of retinitis patients was observed. However, higher levels of NA were associated with a more favorable clinical course. These results indicate that antibodies may modulate progression of disease, and they suggest a possible role for the exogenous administration of NA in patients who develop HCMV retinitis.

Candidate recombinant vaccine for human B19 parvovirus.

Recombinant baculoviruses were used to produce human B19 parvovirus empty capsids composed of only VP2 and VP2 capsids containing 4%, 25%, 35%, or 41% VP1 protein. Immunogenicity of the purified capsids, formulated with or without adjuvant, was evaluated in mice, guinea pigs, and rabbits. Sera were analyzed for total anti-B19 parvovirus antibodies, antibodies specific to the region unique to the VP1 capsid protein, and virus neutralizing antibodies. A relationship was observed between the development of antibodies specific to sequences unique to the VP1 protein and virus neutralization. The polypeptide composition of the empty capsid immunogens appeared to be important for elicitation of potent virus neutralizing activity. VP2 capsid immunogens devoid of VP1 protein, or consisting of only 4% VP1, the composition of naturally occurring virions, were generally poor at eliciting high levels of virus neutralizing activity. Capsids consisting of > or = 25% VP1 protein efficiently and consistently provoked vigorous B19 virus neutralizing responses. Recombinant empty capsids enriched for the VP1 protein should serve as the basis for a human B19 parvovirus vaccine.

Labor and delivery events and risk of sudden infant death syndrome (SIDS)

The purpose of this study was to assess whether labor and delivery events were risk factors for sudden infant death syndrome (SIDS). A nested case-control design was used. From the 1974 cohort of live births for Upstate New York (exclusive of New York City), resident mothers (n = 132,948), SIDS cases, and living controls were selected. Data were abstracted from hospital delivery and vital records for 148 autopsied cases and 355 frequency-matched controls. With the use of unconditional logistic regression, no increase in SIDS risk was observed for artificial rupture of membranes, medication use during labor, induction/augmentation of labor, or anesthesia for delivery. An increased risk of SIDS was observed for labor 16 hours or more (odds ratio (OR) = 2.6, 95% confidence interval (CI) 1.1-6.5) and vaginal breech delivery (OR = 7.2, 95% CI 0.7-72.2). Significant inverse trends were observed for Apgar scores and risk of SIDS.

Familial aggregation of bladder cancer stratified by smoking status.

To assess bladder cancer incidence in first-degree relatives of affected probands, bladder cancer patients and matched control probands provided general demographic and smoking information on their first-degree relatives. Bladder cancer incidence was established through information from the New York State Tumor Registry. The risk ratio for relatives of case probands versus relatives of control probands was 1.9; for relatives who smoked, the risk ratio was 2.1, while for nonsmoking relatives, the risk ratio was 1.8. Results from a proportional hazards regression analysis agreed with those above. These results indicate a familial component that is independent of smoking.

Intrauterine growth retardation and risk of sudden infant death syndrome (SIDS)

The purpose of this study was to assess whether intrauterine growth retardation was associated with an increased risk of sudden infant death syndrome (SIDS). A total of 148 SIDS cases were identified from the Upstate New York (exclusive of New York City) live birth cohort for 1974 (n = 132,948). Dead controls represented all other sudden deaths (n = 114). Live controls were randomly selected and matched to cases on mother's age, race, parity, and residence and infant's birth date (n = 355). Data were collected from vital certificates (response, 97%), medical records (89%), and autopsy reports (100%). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated with the use of logistic regression techniques to control for confounding. With live controls, significant risks were observed for gestations less than 37 weeks (OR = 2.2, CI 1.2-4.1), birth weights less than 2,500 g (OR = 2.5, CI 1.3-5.0) and birth lengths less than or equal to 47.0 cm (OR = 3.4, CI 1.8-6.4). Birth length less than or equal to 47.0 cm was the only significant risk factor observed when dead controls were used (OR = 2.9, CI 1.3-6.8). Risk decreased with increasing gestation and birth size. Postterm infants (greater than or equal to 42 weeks) were at lowest risk (live controls OR = 0.9, CI 0.5-1.6; dead controls OR = 0.6, CI 0.3-1.1). When gestational age was controlled for, SIDS infants were found to have reductions in both weight and length; this suggests that responsible mechanisms begin early in pregnancy.

The stroke rehabilitation outcome study: Part II. Relative merits of the total Barthel index score and a four-item subscore in predicting patient outcomes.

Part I of this series described the background of the study; the characteristics of the patient population; and their functional status before onset of stroke, at rehabilitation admission, at discharge, and at six months after discharge. Results at follow-up showed that patients with higher Barthel index scores living in the community were more likely to be satisfied with life in general, to have more person-to-person contacts, and to be more active in community affairs. Part II describes the utility of two sets of data derived from the admission Barthel index (combinations of independent performance of four basic items of the index vs the total score) in predicting the likely range of Barthel index scores at discharge and functional outcomes at six-month follow-up.

Comparative longitudinal study of 2 methods of scheduling maintenance visits: 4-year data.

116 subjects were recruited from a population of patients previously treated for adult periodontitis and maintained in periodontal health by means of periodic prophylaxes every 3-6 months. The subjects were divided into a control (C) and a test (T) group. A total of 33 patients in the T group and 47 in the C group completed the 4-year study. The C subjects were examined every 6 months and given a prophylaxis every 3 months. The patients in the T group were examined at similar intervals, but prophylaxes were administered according to the individualized scheme of Listgarten and Shiffter, on the basis of a differential microscopic count of subgingival bacterial morphotypes. Recurrent periodontitis was defined as an increase in probing depth of 3 mm or more from baseline measurements. Teeth so affected were sampled microbiologically when the diagnosis of recurrent disease was made and "exited" from the study for treatment. A control microbial sample was taken at the same time from a previously-defined pooled sample of non-affected surfaces with comparatively high, but stable probing depths. During a 4-year period, more than half of the subjects developed at least one recurrence of disease, and one-third of the subjects had 2 or more recurrences of periodontitis. Disease recurred on approximal surfaces 81% and on orovestibular surfaces 19% of the time. There were no significant differences in the rate of disease recurrence between the C and the T group, even though recall intervals in the T group at the 4-year examination averaged 19.4 months and an average of 30.6 months had elapsed since the previous prophylaxis. Both groups exhibited similar plaque index and gingival index scores, similar probing depth and attachment level measurements, and similar proportions of different bacterial morphotypes during the 4-year study. However, differences were noted between examinations for both groups with respect to most of these criteria. This study provides 4-year longitudinal data on the clinical and certain microbiological characteristics of a population of adult patients previously treated for moderate to advanced periodontitis, and subsequently placed on periodontal maintenance. The results indicate that some of these patients may remain in good periodontal health despite the lack of regular tri-monthly recall visits, and that microscopic monitoring of the subgingival microbiota may be of value in identifying these individuals.(ABSTRACT TRUNCATED AT 400 WORDS)

Familial aggregation of congenital dislocation of the hip in a Norwegian population.

Previous studies of congenital dislocation of the hip have not used adequate control groups in estimating the level of genetic influence on that trait. Furthermore, it could not be demonstrated that alleged maternal effects were not an artifact of reporting bias. To that end, information was obtained on the presence of the anomaly in the families of adult twins and their spouses participating in the Norwegian Twin Registry. The prevalence odds ratio for having that disorder in first degree relatives was 10.0. Stratifying by class of relatives, the prevalence odds ratio was 8.1 for fathers, 35.8 for mothers, 12.7 for siblings, and 3.3 for offspring. The increased prevalence odds ratio for mothers over that of fathers suggests a maternal effect. Since both males and females reported on the anomaly for each parental type, it is unlikely that the difference in prevalence odds ratios is due to general reporting bias.

The influence of secular effects and gravidity on the rate of ectopic pregnancy in a Norwegian population.

In order to assess the influence of secular effects and gravidity on the incidence rate of ectopic pregnancy, information from reproductive history questionnaires was obtained for 7804 gravid females identified through the Norwegian Twin Panel. The overall ectopic pregnancy incidence rate was 5.6 per 1000 estimated conceptions, with rates increasing for women born after 1950. Women experiencing their first pregnancy were at lowest risk for that pregnancy being ectopic. When women were stratified by whether they were born before or after 1950, gravidity still had an effect on the incidence rate of ectopic pregnancy. Conversely, year of birth was influential when stratifying by gravidity. The results obtained here suggest that the recent increase in the incidence of ectopic pregnancy is unrelated to the number of prior pregnancies.