Effect of hyperbaric oxygen on post-stroke depression

BACKGROUND

In patients with post-stroke depression (PSD) in diabetes, the situation may be more complex, requiring simultaneous treatment of blood glucose, depressive symptoms, and neurological dysfunction. Hyperbaric oxygen (HBO) therapy can improve tissue oxygen content and improve the situation of ischemia and hypoxia, thus playing a role in protecting brain cells and restoring the function of brain cells. However, there are few studies on HBO therapy for patients with PSD. This study explores the clinical efficacy of such therapy for stroke complicated with depression and diabetes mellitus, and to provide reference and basis for clinical treatment and development through the application of relevant rating scales and laboratory test indicators.

AIM

To evaluate the clinical effects of HBO therapy on patients with diabetes with PSD.

METHODS

A total of 190 diabetic patients with PSD were randomly divided into observation and control groups (95 patients per group). The control group received escitalopram oxalate 10mg once a day for eight weeks. In addition, the ob-servation group was also given HBO therapy, once a day, five times a week, for eight weeks. The Montgomery Depression Rating Scale (MADRS), National Institutes of Health Stroke Scale (NIHSS), hypersensitive C-reactive protein, tumor necrosis factor (TNF)-α, and fasting glucose levels were compared.

RESULTS

There were no significant differences in age, sex, or depression course between the groups (P > 0.05). After HBO treatment, MADRS scores in both groups decreased significantly (14.3 ± 5.2), and were significantly lower in the control group (18.1 ± 3.5). After HBO treatment, NIHSS scores in both groups decreased significantly, and scores in the observation group (12.2 ± 4.0) decreased more than in the control group (16.1 ± 3.4), the difference was statistically significant (P < 0.001). The levels of hypersensitive C-reactive protein and TNF-α in both groups were significantly decreased, and the observation group was significantly lower than the control group (P < 0.001). Fasting blood glucose levels in both groups decreased significantly, and those in the observation group decreased more (8.02 ± 1.10) than in the control group (9.26 ± 1.04), with statistical significance (t = -7.994, P < 0.001).

CONCLUSION

HBO therapy can significantly improve depressive symptoms and neurological dysfunction in patients with PSD, and reduce the levels of hypersensitive C-reactive protein, TNF-α and fasting blood glucose.

[ ≥ ]

Objective: To investigate the safety and efficacy of retroperitoneal laparoscopic selective renal artery branch occlusion with nephron sparing surgery in patients with renal carcinoma of stage ≥ T1b. Methods: From July 2016 to September 2020, 35 patients with renal cancer ≥T1b underwent retroperitoneoscopic nephron sparing surgery in the First Affiliated Hospital of Shenzhen University. The surgical methods were retroperitoneoscopic nephron sparing surgery with total renal artery occlusion (group A) or selective renal artery branch occlusion (group B). Operation time, heat ischemia time, blood transfusion rate, positive margin rate, intraoperative blood loss, postoperative complications and length of hospital stay were compared between the two groups, and the total glomerular filtration rate (GFR) and the single-nephron glomerular filtration rate (sGFR) of the offected kidneys were compared between the two groups before, 3 months after and 12 months after surgery. Results: Among the 35 patients, 19 were male and 16 were female, aged (55.7±8.4) years and the body mass index is (24.6±3.1) kg/m². The tumor diameter was (54.7±10.3) mm. The difference was statistically significant of operative time between group A and B [(103.5±14.3) vs (123.2±14.1) min,P=0.003]. There were no significant differences in thermal ischemia time, blood transfusion rate, positive margin, intraoperative blood loss, incidence of postoperative complications and length of hospital stay between the two groups (all P>0.05). The decrease of renal sGFR in the group A was significantly higher than group B at 3 months and 12 months after surgery [(23.1±3.6) vs (29.1±7.1) ml/min;(25.9±4.7) vs (30.7±7.2),both P<0.05]. Conclusion: Retroperitoneal laparoscopic selective renal artery branch occlusion and neon-sparing surgery for patients with ≥ T1b stage renal carcinoma is a safe and effective surgical method, which can well protect the renal function of patients in the early postoperative stage without increasing intraoperative blood loss and postoperative complications.

A meta-analysis comparing regorafenib with TAS-102 for treating refractory metastatic colorectal cancer

Objective

We performed this meta-analysis to compare the efficacy and toxicity of regorafenib and TAS-102.

Methods

Electronic databases were searched to identify studies comparing the efficacy and safety of regorafenib and TAS-102 in patients with chemotherapy-refractory metastatic colorectal cancer using pooled analyses.

Results

Three clinical trials were included in this analysis. Regarding the reasons for treatment discontinuation, regorafenib was significantly associated with disease progression (odds ratio [OR] = 0.33, 95% confidence interval [CI] = 0.21–0.50) and adverse events (OR = 4.38, 95% CI = 2.69–7.13). However, overall (OR = 0.97, 95% CI = 0.81–1.17) and progression-free survival (OR = 1.01, 95% CI = 0.86–1.18) did not significantly differ between the groups. The most common treatment-related adverse events in the regorafenib group were neutropenia (OR = 0.06, 95% CI = 0.03–0.11), hand–foot syndrome (OR = 50.34, 95% CI = 10.44–242.84), and liver dysfunction (OR = 34.51, 95% CI = 8.30–143.43). Conversely, the incidence of thrombocytopenia did not differ between the two groups.

Conclusions

Regorafenib and TAS-102 have similar efficacy but different adverse event profiles. Differences in the toxicity profiles of the two drugs will help guide treatment selection.

[Influence of different inner dressings in negative-pressure wound therapy on escharectomy wound of full-thickness burn rabbits]

Objective: To explore the influence of different inner dressings in negative-pressure wound therapy (NPWT) on escharectomy wound of full-thickness burn rabbits. Methods: Eighteen Japanese white rabbits were inflicted with full-thickness burn on unilateral back. They were divided into polymer dressing group (PD), biological dressing group (BD), and silver biological dressing group (SBD), according to the random number table, with 6 rabbits in each group. On 3 days post burn, the wounds were performed with escharectomy, and then wounds of rabbits in group PD were covered with polyurethane foam. Wounds of rabbits in group BD were covered with porcine acellular dermal matrix (ADM) and wounds of rabbits in group SBD were covered with silver porcine ADM. Then continuous NPWT was performed on rabbits of the three groups for 7 days. Immediately after surgery and on post surgery day (PSD) 7, general observation of wound was conducted and tissue around the wound was harvested for determination of dry to wet weight ratio. The content of bacteria was counted and the content of tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6 in wound was determined by enzyme-linked immunosorbent assay. Fibroblasts in wound were counted after Masson staining and number of microvessels was counted after CD31 antibody immunohistochemical staining. Data were processed with analysis of variance for repeated measurement, LSD-t test, paired samples t test, and Bonferroni correction. Results: (1) Immediately after surgery, there was no granulation tissue in basal wound of rabbits in the three groups, with rich blood supply and obvious edema. On PSD 7, much granulation tissue was found in basal wound of rabbits in the three groups, with no or mild edema and no obvious redness and swelling in wound edge. (2) There were no significant differences in dry to wet weight ratios of tissue around the wound among and within the three groups immediately after surgery and on PSD 7 (with F values respectively 0.70 and 0.09, t values from 0.17 to 0.52, P values above 0.05). (3) Immediately after surgery, the content of bacteria in wounds of rabbits in groups PD, BD, and SBD was respectively (603.0±146.0) ×10(4,) (573.0±63.0) ×10(4,) and (590.0±100.0)×10(4) colony-forming unit (CFU)/g, with no significant difference among them (F=0.13, P>0.05). On PSD 7, the content of bacteria in wounds of rabbits in groups PD, BD, and SBD were respectively (5.4±0.8) ×10(4,) (4.6±0.9) ×10(4,) and (3.5±0.9)×10(4) CFU/g. Among them, the content of bacteria in wounds of rabbits in group SBD was lower than that in groups PD and BD, respectively (with t values respectively 3.78 and 2.29, P<0.05 or P<0.01). The content of bacteria in wounds of rabbits in the three groups on PSD 7 was decreased compared with that immediately after surgery (with t values from 10.05 to 21.81, P values below 0.01). (4) There was no significant difference in content of TNF-α, IL-1β, and IL-6 in wounds of rabbits in the three groups immediately after surgery and on PSD 7 (with F values from 0.10 to 1.89, P values above 0.05). The content of TNF-α in wounds of rabbits in the three groups on PSD 7 was significantly higher than that immediately after surgery (with t values from 2.93 to 5.01, P<0.05 or P<0.01). (5) There was no significant difference in amount of fibroblasts in wounds of rabbits in the three groups immediately after surgery and on PSD 7 (with F values respectively 0.01 and 0.81, P values above 0.05). The amount of fibroblasts in wounds of rabbits in the three groups on PSD 7 was larger than that immediately after surgery (with t values from 4.78 to 11.58, P values below 0.01). (6) There was no significant difference in number of microvessels in wounds of rabbits in the three groups immediately after surgery and on PSD 7 (with F values respectively 2.42 and 2.49, P values above 0.05). The number of microvessels in wounds of rabbits in the three groups on PSD 7 was larger than that immediately after surgery (with t values from 7.17 to 11.14, P values below 0.01). Conclusions: SBD is better at inhibiting the growth of bacteria. PD, BD, and SBD have almost the same effects on reducing tissue edema and inflammatory reaction, and on promoting the accumulation of collagen fibers and tissue vascularization.

Quantifying Sarcopenia Reference Values Using Lumbar and Thoracic Muscle Areas in a Healthy Population

BACKGROUND

Sarcopenia is defined as the loss of skeletal muscle mass and function associated with aging. Muscle mass can be reliably and accurately quantified using clinical CT scans but reference measurements are lacking, particularly in healthy US populations.

METHODS

Two-phase CT scans from healthy kidney donors (age 18-40) at the University of Michigan between 1999-2010 were utilized. Muscle mass was quantified using two thoracic and two lumbar muscle cross-sectional area (CSA) measures. Indexed measurements were computed as area divided by height-squared. Paired analyses of non-contrast and contrast phases and different Hounsfield Unit (HU) ranges for muscle were conducted to determine their effect on CSA muscle measures. We report the means, standard deviations, and 2SD sarcopenia cutoffs from this population.

RESULTS

Healthy population CSA (cm2) cutoffs for N=604 males/females respectively were: 34.7/20.9 (T12 Dorsal Muscle), 91.5/55.9 (T12 Skeletal Muscle), 141.7/91.2 (L3 Skeletal Muscle), 23.5/14.3 (L4 Total Psoas Area), and 23.4/14.3 (L4 Psoas Muscle Area). Height-indexed CSA (cm2/m2) cutoffs for males/females respectively were: 10.9/7.8 (T12 Dorsal Muscle), 28.7/20.6 (T12 Skeletal Muscle), 44.6/34.0 (L3 Skeletal Muscle), 7.5/5.2 (L4 Total Psoas Area), and 7.4/5.2 (L4 Psoas Muscle Area). We confirmed that a mask of -29 to 150 HU is optimal and shows no significant difference between contrast-enhanced and non-contrast CT scan CSA measurements.

CONCLUSIONS

We quantified reference values for lumbar and thoracic muscle CSA measures in a healthy US population. We defined the effect of IV contrast and different HU ranges for muscle. Combined, these results facilitate the extraction of clinically valuable data from the large numbers of existing scans performed for medical indications.

[Effects on wound bed of deep burn following eschar excision with different wound management in rabbits]

OBJECTIVE

To compare the effects on wound bed of deep burn following eschar excision with different wound management in rabbits.

METHODS

Eighteen full-thickness burns models of Japanese white rabbits were established. They were randomly divided into 3 groups of traditional dressing, biological dressing and negative pressure wound therapy (NPWT) (n=6 each), according to the random number table. Eschar excision was performed three days later. The wound bed was observed and wound tissue was harvested for counting the quantity of bacteria, tissue dry wet ratio, measuring the level of tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β and IL-6, the amount of collagen fibers and the microvessel density instantly and again seven days later. Statistical analyses were performed.

RESULTS

The NPWT group was better than other groups by observing the wound bed. The quantity of bacteria of traditional dressing group, biological dressing group and NPWT group at the time point of seven days after escharectomy turned out to be (9.4±1.5)×10(4,) (8.1±2.7)×10(4,) (3.9±0.7)×10(4) cfu/g, the NPWT group was significantly lower than traditional dressing group and biological dressing group (both P<0.05), and all lower than that at the time point of the day when escharectomy was performed (576.9±169.5)×10(4,) (589.9±99.6)×10(4,) (583.0±160.4)×10(4) cfu/g ( all P<0.05). There were no statistically significant differences among three groups at two time points in tissue dry wet ratio (all P>0.05). The IL-6 of biological dressing group was higher than that of traditional dressing group at the time point of seven days after the eschar excision was performed[(94±10) vs (76±8) ng/L, P<0.05]. The amount of collagen fibers of three group at the time point of seven days after escharectomy turned out to be (60±9), (55±12), (77±17). The NPWT group was significantly higher than traditional dressing group and biological dressing group (P<0.05), and all higher than that at the time point of the day when escharectomy was performed[(39±6), (39±11), (38±6)](all P<0.05). The microvessel density of three groups at the time point of seven days after escharectomy turned out to be (42±6), (53±4), (82±10). The NPWT group was higher than that of the other two groups, and biological dressing group was higher than that of traditional dressing group (all P<0.05). The biological dressing group and NPWT group were both higher than that of the day when the eschar excision was performed (36±5) and (36±5) (P<0.05).

CONCLUSIONS

NPWT is the optimal selection for wound to inhibit the growth of bacteria, promote the accumulation of collagen and tissue vascularization. But these managements have similar effects on reducing tissue edema and inflammatory reaction.

Lipopolysaccharide binding protein inhibitory peptide protects against acetaminophen-induced hepatotoxicity

Acetaminophen (APAP)-induced liver injury remains the main cause of acute liver failure in the United States. Our previous work demonstrated that LPS binding protein (LBP) knockout mice are protected from APAP-induced hepatotoxicity. LBP is known to bind avidly to LPS, facilitating cellular activation. In this study, we sought to specifically inhibit the interaction between LBP and LPS to define the role of this interaction in APAP-induced liver injury. The peptide LBPK95A was able to inhibit LBP-mediated LPS activation of RAW 267.4 cells in a dose-dependent manner in vitro. In vivo, C57Bl/6 mice were treated with either LBPK95A or vehicle control concurrently with the administration of APAP (350 mg/kg). Mice treated with LBPK95A had significantly lower serum aspartate aminotransferase and alanine aminotransferase levels. Morphometric analysis of the liver tissue showed significantly less liver injury in mice treated with LBPK95A. To assess whether the LBPK95A altered glutathione depletion and APAP metabolism, we measured total glutathione levels in the liver after APAP. We found no difference in the glutathione levels and APAP-adduct formation between LBPK95A vs. vehicle control both at baseline and after APAP. In conclusion, our results support the hypothesis that LBP-induced liver injury after APAP is due to its ability to mediate activation by endogenous LPS. Our results suggest that blocking LBP-LPS interactions is a potential therapeutic avenue for the treatment of APAP-induced liver injury.

Investigation of valence orbitals of propene by electron momentum spectroscopy

The binding energy spectra and momentum distributions of all valence orbitals of propene were studied by electron momentum spectroscopy (EMS) as well as Hartree-Fock and density functional theoretical calculations. The experiment was carried out at impact energies of 1200 eV and 600 eV on the state-of-the-art EMS spectrometer developed at Tsinghua University recently. The experimental momentum profiles of the valence orbitals were obtained and compared with the various theoretical calculations. Moreover, the experiment with a new analysis method presents a strong support for the correct ordering of the orbital 8a' and 1a'', i.e., 9a' < 8a' < 1a'' < 7a'.

Direct observation of distorted wave effects in ethylene using the (e,2e) reaction

We report here the direct measurements of electron momentum distributions for ethylene using the (e,2e) reaction at different impact energies from 400 to 2400 eV. The "turn up" effects in the (e,2e) cross sections of the 1b(3g) orbital compared with the plane-wave impulse approximation calculations were observed at low and high momentum regions, and such discrepancies become smaller with the increase of the impact electron energies. It is suggested that the observed discrepancies are due to the distorted-wave effects in molecules, while appropriate theoretical calculations using distorted waves in molecules could not be achieved until now.

An investigation of valence shell orbital momentum profiles of difluoromethane by binary (e,2e) spectroscopy

The electron binding energy spectra and momentum profiles of the valence orbitals of difluoromethane, also known as HFC32 (HFC-hydrofluorocarbon) (CH(2)F(2)), have been studied by using a high resolution (e,2e) electron momentum spectrometer, at an impact energy of 1200 eV plus the binding energy, and by using symmetric noncoplanar kinematics. The experimental momentum profiles of the outer valence orbitals and 4a(1) inner valence orbital are compared with the theoretical momentum distributions calculated using Hartree-Fock and density functional theory (DFT) methods with various basis sets. In general, the shapes of the experimental momentum distributions are well described by both the Hartree-Fock and DFT calculations when large and diffuse basis sets are used. However, the result also shows that it is hard to choose the different calculations for some orbitals, including the methods and the size of the basis sets employed. The pole strength of the ionization peak from the 4a(1) inner valence orbital is estimated.

The outer valance orbital electron densities of cyclopentane by binary (e,2e) spectroscopy

The binding energy spectra and electron distributions in momentum space of the valence orbitals of cyclopentane (C(5)H(10)) are studied by Electron Momentum Spectroscopy (EMS) in a noncoplanar symmetric geometry. The impact energy was 1200 eV plus binding energy and energy resolution of the EMS spectrometer was 1.2 eV. The experimental momentum profiles of the outer valence orbitals are compared with the theoretical momentum distributions calculated using Hartree-Fock and density functional theory (DFT) methods. The shapes of the experimental momentum distributions are generally quite well described by both the Hartree-Fock and DFT calculations when the large and diffuse basis sets are used.

Increased severity of alcoholic liver injury in female rats: role of oxidative stress, endotoxin, and chemokines

Alcoholic liver injury is more severe and rapidly developing in women than men. To evaluate the reason(s) for these gender-related differences, we determined whether pathogenic mechanisms important in alcoholic liver injury in male rats were further upregulated in female rats. Male and age-matched female rats (7/group) were fed ethanol and a diet containing fish oil for 4 wk by intragastric infusion. Dextrose isocalorically replaced ethanol in control rats. We analyzed liver histopathology, lipid peroxidation, cytochrome P-450 (CYP)2E1 activity, nonheme iron, endotoxin, nuclear factor-kappa B (NF-kappa B) activation, and mRNA levels of cyclooxygenase-1 (COX-1) and COX-2, tumor necrosis factor-alpha (TNF-alpha), monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-2 (MIP-2). Alcohol-induced liver injury was more severe in female vs. male rats. Female rats had higher endotoxin, lipid peroxidation, and nonheme iron levels and increased NF-kappa B activation and upregulation of the chemokines MCP-1 and MIP-2. CYP2E1 activity and TNF-alpha and COX-2 levels were similar in male and female rats. Remarkably, female rats fed fish oil and dextrose also showed necrosis and inflammation. Our findings in ethanol-fed rats suggest that increased endotoxemia and lipid peroxidation in females stimulate NF-kappa B activation and chemokine production, enhancing liver injury. TNF-alpha and COX-2 upregulation are probably important in causing liver injury but do not explain gender-related differences.

Comorbid illness is an important determinant of health-related quality of life in patients with chronic hepatitis C

OBJECTIVES

Chronic hepatitis C (CHC) patients selected for entry into treatment trials have been reported to have impaired health-related quality of life (HRQOL). However, these trials have an inherent selection bias, and HRQOL in CHC patients may have been underestimated because of the exclusion of patients with comorbid illness. The aim of this study was to assess HRQOL in an unselected group of CHC patients and to identify factors associated with impairment in HRQOL.

METHODS

A total of 220 consecutive eligible CHC patients were enrolled from a hepatology clinic. HRQOL was assessed by the short form 36 (SF-36) and comorbid illnesses were assessed by an interview.

RESULTS

CHC patients had significantly lower SF-36 scores in all subscales and in the summary scales when compared to those of the healthy general population in the United States (p < 0.001). Compared to CHC patients entering treatment trials, our patients had lower SF-36 scores on five subscales (p < 0.001). The presence of comorbid illness was the most important predictor of HRQOL in CHC patients. However, CHC alone resulted in significantly lower SF-36 scores in all subscales and summary scales (p < or = 0.003) compared to those of the healthy U.S. population. There was no correlation between SF-36 scores and history of i.v. drug use or dependence. alcohol dependence. and serum aminotransferase levels.

CONCLUSIONS

We conclude that unselected CHC patients presenting for medical evaluation have a reduced HRQOL, which is lower than that reported for CHC patients entering treatment trials. CHC alone is associated with significant impairment in HRQOL, but the presence of comorbid illness leads to further diminution in HRQOL.

Outcome of liver transplantation for hepatitis B: report of a single center's experience

Results of liver transplantation (LT) for hepatitis B have improved significantly with the use of hepatitis B immune globulin (HBIG) and/or lamivudine. The aim of this study is to review the long-term outcome of patients who underwent LT for hepatitis B. Records of 41 patients who underwent LT for hepatitis B and survived 3 months or longer post-LT were reviewed. Twenty patients were administered no immunoprophylaxis or short-term intramuscular HBIG, whereas 21 patients were administered high-dose intravenous (IV) HBIG. Median post-LT follow-up in these 2 groups was 76 months (range, 4 to 155 months) and 25 months (range, 4 to 68 months), respectively. Hepatitis B recurred in 15 (75%) and 4 patients (19%) who underwent LT in the pre-HBIG and post-HBIG eras, respectively. Cumulative rates of recurrent hepatitis B at 1 and 3 years post-LT in these 2 groups were 66% and 77% and 20% and 20%, respectively (P <.001). Recurrent hepatitis B in the post-HBIG era correlated with antibody to hepatitis B surface antigen titer less than 100 IU/L. Nine patients with recurrent hepatitis B were administered lamivudine for 13 to 49 months (median, 28 months); 6 patients continued to have stable or improved liver disease, whereas 3 patients developed virological breakthrough with slow deterioration of liver disease. Long-term IV HBIG is effective in preventing recurrent hepatitis B. The risk for recurrent hepatitis B is negligible after the first year post-LT. Among patients with no virological breakthrough, lamivudine can stabilize or improve liver disease for up to 4 years in patients with recurrent hepatitis B post-LT.

Protegrin-1 enhances bacterial killing in thermally injured skin

OBJECTIVE

Septic complications and the emergence of drug-resistant microbes represent serious risks to patients. Recently, naturally occurring peptides have been discovered that possess potent and broad-spectrum antimicrobial activity. Protegrin-1 is particularly attractive for clinical use in human wounds because, unlike defensins, protegrin-1 retains broad antimicrobial and antifungal activity at physiologic salt concentration and in the presence of serum. The objective of this study was to examine the efficacy of protegrin-1 in killing multiple drug-resistant microbes isolated from human burn patients.

DESIGN

For thein vitroexperiment, bilayer radial diffusion was performed comparing standard antibiotics with protegrin-1 on multiple-drug-resistant microbial organisms isolated from infected burn wounds. In vivo, rats received a 20% total body surface area partial-thickness burn by immersion in 60 degrees C water for 20 secs followed by wound seeding with 106 colony forming units of Silvadene-resistant Pseudomonas aeruginosa.

SETTING

University of Michigan research laboratory.

SUBJECTS

Adult, male Sprague-Dawley rats.

INTERVENTIONS

Rats were randomized into three groups: those receiving synthetic protegrin-1, acetic acid (carrier), or gentamicin (positive control). Protegrin-1 was administered by topical application or intradermal injection. Wound tissues were harvested aseptically at different time points for quantitative bacterial counts.

MEASUREMENTS AND MAIN RESULTS

In vivo and in vitro experiments revealed rapid and significant decreases in bacterial counts for protegrin-1-treated groups compared with controls.

CONCLUSIONS

This study shows that protegrin-1 potentially may be used as an alternative or adjunct therapy to standard agents used to treat wound infections.

Feasibility of biolistic gene therapy in burns

Skin is an especially attractive target for genetic manipulation because it is readily accessible and easily monitored for both the presence and the expression of inserted genes. This study was designed to assess the feasibility of particle mediated gene transfer to burned skin and to compare the transfection efficiency, anatomic distribution, and duration of transgene expression achievable in normal versus burned skin. Two days following scald injury of varying depths in 60 degrees C water (10 s: superficial partial; 20 s: deep partial; 40 s: full thickness) reporter gene (beta-galactosidase) constructs were delivered using a gene gun at various helium pressures (200-600 psi) to normal and burned skin. A time course study was performed to examine the kinetics of transgene expression. Animals received a superficial partial thickness burn and were sacrificed 12 h, 1, 3, 5, 7, 14, or 21 days after gene transfer. India Ink injection and immunohistochemistry were used to assess the depth of the scald injury. Transfection efficiency was measured in skin homogenates 24 h after gene transfer by morphometric and chemoluminescent assays. We found that the extent of tissue damage was directly related to the duration of heat source exposure. Reporter gene activity was significantly higher in superficial partial thickness burns compared to normal controls and gradually declined with increasing tissue injury. No activity was seen in the full thickness burn group. Beta-galactosidase activity reached a maximum level 12 h after gene transfer in both normal and superficial partial thickness burned skin with no levels seen after 5 days post-transfection. These findings indicate that particle-mediated gene transfer in thermally injured skin is feasible and may provide a means of introducing biologic agents into injured tissue capable of enhancing bacterial clearance and improving wound healing.

Lipopolysaccharide-binding protein accelerates and augments Escherichia coli phagocytosis by alveolar macrophages

BACKGROUND

The first step in bacterial clearance by leukocytes is attachment and phagocytosis. Although lipopolysaccharide-binding protein (LBP) is best known for potentiating LPS-induced cytokine production through a CD14-dependent pathway, recent studies suggest that LBP plays a critical role in clearance of gram-negative bacteria and is essential for survival after bacterial challenge. We therefore sought to examine LBP's effect on Escherichia coli phagocytosis by alveolar macrophages (AMs) and to determine if this effect is mediated through CD14.

MATERIALS AND METHODS

Phosphatidylinositol-specific phospholipase C (PIPLC)-treated and untreated rat AMs were incubated in the presence of increasing doses of recombinant LBP or negative control protein (choramphenicol acetyltransferase) prior to E. coli-FITC (Ec-F) BioParticle challenge. Phagocytosed bacteria were assayed by fluorescence measurement. A time course study was also performed.

RESULTS

LBP potentiated phagocytosis of Ec-F BioParticles by AMs in a dose-dependent fashion. Kinetic studies showed that LBP augmented Ec-F phagocytosis by 76% at 30 min. Treatment of AMs with PIPLC to remove CD14 resulted in only a partial decrease in LBP-mediated enhancement of phagocytosis.

CONCLUSION

These results clearly demonstrate that LBP plays an important role in enhancing Ec-F binding and phagocytosis in a time- and dose-dependent manner. This observed increase may not require the presence of CD14 as significant potentiation of phagocytosis still occurred after PIPLC treatment. We postulate that the LBP-mediated increase in Ec-F phagocytosis can occur in the absence of CD14 through the presence of another receptor.

Mechanism of the alcohol cyclic pattern: role of the hypothalamic-pituitary-thyroid axis

The cause of the cycle of urinary alcohol levels (UALs) in rats fed ethanol continually at a fixed rate is unknown. Rats were fed ethanol intragastrically at a constant dose for 2 mo, and daily body temperatures and UALs were recorded. Body temperature cycled inversely to UAL, suggesting that the rate of metabolism could be mechanistically involved in the rate of ethanol elimination during the cycle. To document this, whole body O(2) consumption rate was monitored daily during the cycle. The rate of O(2) consumption correlated positively with the change in body temperature and negatively with the change in UAL. Since the metabolic rate responds to changes in body temperature, thyroid hormone levels were measured during the UAL cycle. T(4) levels correlated positively with the O(2) consumption rate and negatively with the UALs. In a second experiment using propylthiouracil treatment, UALs did not cycle and a fall in body temperature failed to stimulate an increase in the rate of ethanol elimination. Consequently, rats died of overdose. Likewise, in a third experiment using rats with severed pituitary stalks, UALs failed to cycle and rats died of overdose. From these observations it was concluded that the UAL cycle depends on an intact hypothalamic-pituitary-thyroid axis response to the ethanol-induced drop in body temperature by increasing the rate of ethanol elimination.

Skin lipopolysaccharide-binding protein and IL-1beta production after thermal injury

In response to a burn injury, skin can have an inflammatory response characterized by the production of inflammatory cytokines, recruitment of immune cells, containment of invading organisms, and clearance of noxious substances from the wound. Lipopolysaccharide-binding protein (LBP) is a molecule that is capable of coordinating all 4 functions; we previously found evidence that suggested that LBP is produced within surgical wounds. Because of the central role of LBP in the response to bacterial infection, as well as in the high rate of infection after burn injuries, we sought to determine whether a thermal injury could affect wound LBP production and thereby affect host responses against bacterial infection. Rats were given either a burn or a sham burn and were killed 24, 48, and 72 hours after the injuries. Wound specimens were assayed for bacterial counts and for the presence of LBP, messenger (m)RNA, and interleukin (IL)-1beta mRNA. Wound LBP mRNA was significantly upregulated at 24 hours in the group with burn injuries (P < .05; burn vs sham burn); this was followed by decreases at 48 and 72 hours. Immunohistochemistry showed LBP protein in the epidermis of animals with burns. Bacterial counts increased in the group with burn injuries (P < .05; burn vs sham burn) and continued to rise for 72 hours. IL-1beta mRNA levels were elevated at all time points in the group with burn injuries (P < .05). These results suggest an inverse correlation between burn wound LBP expression and bacterial wound counts. This failure to maintain local LBP production after severe thermal injury despite localized inflammation shown by high IL-1beta levels may predispose local wounds to bacterial invasion.

Kupffer cell activation by lipopolysaccharide in rats: role for lipopolysaccharide binding protein and toll-like receptor 4

Lipopolysaccharide (LPS) binding protein (LBP) is a key serum factor that mediates LPS activation of mononuclear cells. In the presence of LBP, 1/1,000 the concentration of LPS is sufficient to activate peripheral blood monocytes. Previous studies with Kupffer cells have shown a variable effect of serum on LPS activation of these cells and led to the conclusion that, unlike extrahepatic mononuclear cells, Kupffer cells do not respond to LPS in an LBP-dependent fashion. Because there are multiple components in serum other than LBP that might affect LPS activation, these reports with serum are difficult to interpret. To investigate the specific role of LBP in LPS activation of Kupffer cells, we produced a functional recombinant rat LBP using a baculovirus expression system, which we used to selectively examine the role of LBP's on Kupffer-cell function. Isolated Kupffer cells exposed to increasing concentrations of LPS (0, 1, 10 ng/mL) showed a dose-dependent increase in TNF-alpha production, which was augmented and accelerated by the presence of LBP. The effects of LBP on Kupffer cell activation by LPS are dependent on a functional Toll-like receptor 4 (Tlr 4) because Kupffer cells from C3H/HeJ mice failed to respond to LPS in the presence of LBP. LBP plays an important role in mediating Kupffer cell activation by LPS, and these effects are dependent on the presence of functioning Tlr 4.

Activation of nuclear factor kappa B and cytokine imbalance in experimental alcoholic liver disease in the rat

Inflammatory stimuli and lipid peroxidation activate nuclear factor kappa B (NF-kappaB) and upregulate proinflammatory cytokines and chemokines. The present study evaluated the relationship between pathological liver injury, endotoxemia, lipid peroxidation, and NF-kappaB activation and imbalance between pro- and anti-inflammatory cytokines. Rats (5 per group) were fed ethanol and a diet containing saturated fat, palm oil, corn oil, or fish oil by intragastric infusion. Dextrose isocalorically replaced ethanol in control rats. Pathological analysis was performed and measurements of endotoxin were taken, lipid peroxidation, NF-kappaB, and messenger RNA (mRNA) levels of proinflammatory cytokines (tumor necrosis factor-alpha [TNFalpha], interleukin-1 beta [IL-1beta], interferon-gamma, [IFN-gamma], and IL-12), C-C chemokines (regulated upon activation, normal T cell expressed and secreted [RANTES], monocyte chemotactic protein [MCP]-1, macrophage inflammatory protein [MIP]-1alpha), C-X-C chemokines (cytokine induced neutrophil chemoattractant (CINC), MIP-2, IP-10, and epithelial neutrophil activating protein [ENA]-78), and anti-inflammatory cytokines (IL-10, IL-4, and IL-13). Activation of NF-kappaB and increased expression of proinflammatory cytokines C-C and C-X-C chemokines was seen in the rats exhibiting necroinflammatory injury (fish oil-ethanol [FE] and corn oil-ethanol[CE]). These groups also had the highest levels of endotoxin and lipid peroxidation. Levels of IL-10 and IL-4 mRNA were lower in the group exhibiting inflammatory liver injury. Thus, activation of NF-kappaB occurs in the presence of proinflammatory stimuli and results in increased expression of proinflammatory cytokines and chemokines. The Kupffer cell is probably the major cell type showing activation of NF-kappaB although the contribution of endothelial cells and hepatocytes cannot be excluded. Downregulation of anti-inflammatory cytokines may additionally exacerbate liver injury.

Activation of nuclear factor kappa B and cytokine imbalance in experimental alcoholic liver disease in the rat

Inflammatory stimuli and lipid peroxidation activate nuclear factor kappa B (NF-kappaB) and upregulate proinflammatory cytokines and chemokines. The present study evaluated the relationship between pathological liver injury, endotoxemia, lipid peroxidation, and NF-kappaB activation and imbalance between pro- and anti-inflammatory cytokines. Rats (5 per group) were fed ethanol and a diet containing saturated fat, palm oil, corn oil, or fish oil by intragastric infusion. Dextrose isocalorically replaced ethanol in control rats. Pathological analysis was performed and measurements of endotoxin were taken, lipid peroxidation, NF-kappaB, and messenger RNA (mRNA) levels of proinflammatory cytokines (tumor necrosis factor-alpha [TNFalpha], interleukin-1 beta [IL-1beta], interferon-gamma, [IFN-gamma], and IL-12), C-C chemokines (regulated upon activation, normal T cell expressed and secreted [RANTES], monocyte chemotactic protein [MCP]-1, macrophage inflammatory protein [MIP]-1alpha), C-X-C chemokines (cytokine induced neutrophil chemoattractant (CINC), MIP-2, IP-10, and epithelial neutrophil activating protein [ENA]-78), and anti-inflammatory cytokines (IL-10, IL-4, and IL-13). Activation of NF-kappaB and increased expression of proinflammatory cytokines C-C and C-X-C chemokines was seen in the rats exhibiting necroinflammatory injury (fish oil-ethanol [FE] and corn oil-ethanol[CE]). These groups also had the highest levels of endotoxin and lipid peroxidation. Levels of IL-10 and IL-4 mRNA were lower in the group exhibiting inflammatory liver injury. Thus, activation of NF-kappaB occurs in the presence of proinflammatory stimuli and results in increased expression of proinflammatory cytokines and chemokines. The Kupffer cell is probably the major cell type showing activation of NF-kappaB although the contribution of endothelial cells and hepatocytes cannot be excluded. Downregulation of anti-inflammatory cytokines may additionally exacerbate liver injury.

CD14 expression and production by human hepatocytes

BACKGROUND/AIMS

CD14 has been identified as a receptor for LPS and is present both in a membrane-bound and a soluble form. Membrane CD14 (mCD14) is predominantly expressed on monocytes, macrophages and granulocytes. The source of soluble CD14 (sCD14) is as yet unclear. Previous investigation using monocytes has shown that sCD14 can be derived either from the shedding of mCD14 or from direct secretion by monocytes. Whether the monocyte is the sole or even the major source of sCD14 is as yet uncertain. Clearance of LPS from the bloodstream is thought to be primarily mediated by the liver. Production of CD14 by hepatocytes would potentially provide a powerful mechanism by which the liver could clear LPS, and therefore we examined the ability of human hepatocytes to produce CD14.

METHODS

Human hepatocytes were isolated using collagenase perfusion.

RESULTS

Human hepatocytes were found to have CD14 mRNA by Northern blot analysis. Western blot analysis and immunohistochemical staining confirmed CD14 protein in primary hepatocyte cultures. Further studies showed that a liver epithelial-like cell line AKN-1 is capable of producing CD14. Comparisons of the size of hepatocyte-derived CD14 protein with the sCD14 protein from the human monocytic leukemia cell line HL60 suggested that a slightly larger form of CD14 is expressed by human liver cells.

CONCLUSION

This is the first study to demonstrate production of CD14 by human hepatocytes.

Pulmonary LPS-binding protein (LBP) upregulation following LPS-mediated injury

BACKGROUND

The acute respiratory distress syndrome (ARDS) causes significant morbidity and mortality among trauma patients. Although multiple factors have been implicated, pulmonary injury in this population may be due to inflammatory mediators released in response to stimuli such as endotoxin (LPS). LBP plays an integral part in LPS-mediated release of inflammatory cytokines and increased local expression of LBP as the result of a primary injury may prime the lung to secondary LPS-mediated damage.

MATERIALS AND METHODS

To determine the magnitude of pulmonary LBP upregulation following LPS injury we challenged rats with either intravenous (IV) or intratracheal (IT) LPS. Animals from each group were euthanized at 1, 2, 4, and 8 h postchallenge. Lung LBP and CD14 mRNA levels were assayed by Northern blot. Serum and bronchoalveolar lavage (BAL) fluid were assayed for inflammatory cytokines (TNF-alpha, MCP-1, IL-1beta, IL-6, and IL-10) by ELISA.

RESULTS

LBP and CD14 mRNA levels were found to increase significantly in lung tissue after both IV and IT LPS with the IV LPS animals having a greater increase over 8 h. Serum TNF-alpha was significantly elevated in the IV LPS group whereas very low levels were detected in the BAL. Only BAL TNF-alpha was increased in the IT group at 8 h.

CONCLUSION

Local pulmonary LBP and CD14 mRNA are both upregulated after either systemic or local LPS exposure. Such upregulation may render thelung more susceptible to local immune overactivation and injury during subsequent exposures to LPS.

Tissue coexpression of LBP and CD14 mRNA in a mouse model of sepsis

BACKGROUND

Lipopolysaccharide binding protein (LBP) markedly increases the sensitivity of immune cells to LPS and CD14 expression correlates with cellular responsiveness to LPS. LBP gene expression can be induced in multiple organs following injury and CD14 upregulation on monocytes correlates with the infection and mortality rates in severely injured patients. We sought to determine the time-course induction of LBP and CD14 gene expression following experimental peritonitis.

MATERIAL AND METHODS

BALB/c mice were subjected to laparotomy alone or laparotomy with cecal ligation and puncture and treated with Imipenem. At serial time points, animals were sacrificed and tissues harvested for isolation of RNA and protein. LBP, CD14, and cytokine mRNAs were analyzed by Northern blot analysis and TaqMan fluorescent quantitative RT-PCR.

RESULTS

LBP and CD14 mRNA levels were significantly increased in all three organs from CLP mice compared to sham-operated mice. IL-1 mRNA levels increased in all three organs following CLP with significantly higher levels found in the lungs compared to the kidney and liver. No significant differences were noted in local TNF mRNA levels.

CONCLUSIONS

LBP, CD14, and IL-1 mRNA levels are induced concurrently in the lung, kidney, and liver after cecal ligation and puncture. Given the synergistic affect of LBP and CD14 in potentiating LPS-induced production of inflammatory cytokines and the hypothesized role of such cytokines in the etiology of MSOF following injury and sepsis, our findings suggest a mechanism by which these organs may be rendered more susceptible to a "second hit" from endotoxemia after initial injury.

CD14 and lipopolysaccharide binding protein expression in a rat model of alcoholic liver disease

Lipopolysaccharide-binding protein (LBP) and CD14 play key intermediary roles in the activation of cells by endotoxin. As endotoxin has been postulated to participate in promoting pathological liver injury in alcoholic liver disease, we investigated the role of LBP and CD14 in alcoholic liver injury. Rats were fed intragastrically ethanol or dextrose and either medium-chain triglycerides, corn oil, or fish oil for 4 weeks. Kupffer cells, endothelial cells, and hepatocytes were isolated. LBP and CD14 mRNA levels were measured in liver and individual cell types. The highest levels of LBP and CD14 mRNA levels in the liver were found in the fish oil/ethanol group, which was also the group with the greatest degree of pathological injury and inflammation. CD14 mRNA levels were also significantly elevated in groups fed unsaturated fatty acids with dextrose. CD14 expression was localized to the Kupffer cells and LBP expression to the hepatocytes. Expression of CD14 mRNA was also found in nonmyeloid cells in the two experimental groups (fish oil/ethanol and corn oil/ethanol) that had liver necrosis and inflammation. Our results suggest that enhanced LBP and CD14 expression correlates with the presence of pathological liver injury in alcoholic liver injury. Furthermore, unsaturated fatty acids may prime cells to respond to endotoxin by enhancing CD14 expression.

Increased expression of interferon-gamma in a rat model of chronic intestinal allograft rejection

Chronic rejection remains a major cause of late graft dysfunction. Although much research has focused on acute rejection, little is known about the mechanisms of chronic rejection. Our group has recently reported evidence of significant intestinal smooth muscle hypertrophy and hyperplasia associated with abnormal contractile and electrical activities in a rat model of chronic intestinal rejection. The changes in the smooth muscle layer are associated with a significant inflammatory infiltrate. In order to further delineate the immune mechanisms of chronic rejection, we sought to clarify the nature of this infiltrate. Orthotopic small bowel transplantation was performed using an allogeneic (ACI-Lewis) rat combination. The rats only received immunosuppression for the first 28 days posttransplantation (cyclosporine 15 mg/kg daily from postoperative day 0 to 6 and every other day from postoperative day 7 to 28). This led to chronic rejection of the graft by day 90, at which time the rats were sacrificed. Analysis by immunohistochemistry revealed NK and CD5+ leukocytes infiltrating the muscular layer. Examination of cytokine production by radiolabeled polymerase chain reaction showed high levels of steady state interferon-gamma mRNA in full thickness intestinal segments and within the isolated muscularis of chronically rejecting intestinal allografts as compared to syngeneic and control grafts. Interferon-gamma mRNA was localized to both the muscularis and mucosa. Interestingly, positively hybridized cells within the muscularis tended to preferentially localize to the myenteric and submucosal plexuses suggesting potential role for this cytokine in chronic intestinal ejection.

Update of the Adult and Pediatric Liver Transplant Program at the University of Michigan

Significant technical innovations and improvements in immunosuppression have been introduced into our liver transplant program since its inception in 1985. The indications for transplantation have been extended to younger and older patients, and simultaneously more patients with comorbidities have been accepted for transplant. The net impact of these changes has been a continuing trend toward improved survival. Overall, patients with hepatitis B or malignancy have had poor survival rates. The introduction of prophylactic anti-hepatitis B immunoglobulin and lamivudine, and better selection of patients with malignancy may improve results for these patients in the future. As in other programs, our most vexing problem is the continuing scarcity of donor organs which has led to an ever-expanding waiting list, more deaths while awaiting transplant, and more suffering before transplantation. The introduction of living donor hepatic transplantation will be of some help in alleviating this shortage. We are confident that the evolution of our program into a joint multidisciplinary structure will provide more efficient, convenient and cost-effective care to our patients.

Role of lipopolysaccharide (LPS), interleukin-1, interleukin-6, tumor necrosis factor, and dexamethasone in regulation of LPS-binding protein expression in normal hepatocytes and hepatocytes from LPS-treated rats

Lipopolysaccharide (LPS)-binding protein (LBP) has been reported to be an acute-phase protein. LBP binds to LPS with a high affinity; LPS-LBP complexes then interact with the receptor CD14, resulting in increased expression of LPS-inducible genes. Hepatocytes represent a major source of LBP, but little is known about the regulation of rodent hepatocyte LBP synthesis. In these studies, undertaken to characterize hepatocyte LBP expression, we show that greater-than-20-fold increases in LBP mRNA levels in hepatocytes occurred following injection of LPS or turpentine in rats. In primary cultures of rat hepatocytes, the addition of interleukin-6 (IL-6) and LPS led to 4.5- and 3.2-fold stimulation in LBP mRNA levels, respectively. The induction of LBP by IL-6 or LPS was attenuated by dexamethasone. In contrast to IL-6 and LPS, in the presence of 10(-6) M dexamethasone, IL-1 and tumor necrosis factor (TNF) led to maximal LBP mRNA induction levels, 4.7- and 3.8-fold, respectively, suggesting that IL-6 and LPS stimulate LBP expression by mechanisms different from those of IL-1 and TNF. Similar induction levels of LBP mRNA were seen in rat H35 hepatoma cells for all four stimuli, and dexamethasone inhibited these responses. Dexamethasone alone increased the spontaneous induction in primary hepatocytes at early time points but suppressed induction at later time points. Furthermore, hepatocytes from rats treated with LPS in vivo exhibited a > 10-fold increase in mRNA expression in response to LPS and enhanced responses to TNF and IL-1. As with the normal hepatocytes, dexamethasone inhibited the LPS-dependent induction in the LPS-treated rat hepatocytes. These data suggest that LBP synthesis by hepatocytes is under the control of LPS, IL-1, TNF, IL-6, and glucocorticoids and that the LPS treatment primes hepatocytes for subsequent responses to LPS, TNF, and IL-1 for LBP synthesis.

Induction of lipopolysaccharide-binding protein gene expression in cultured rat pulmonary artery smooth muscle cells by interleukin 1 beta

Lipopolysaccharide (LPS)-binding protein (LBP) binds with high affinity to LPS, and the LBP-LPS complex enhances cellular inflammatory responses to LPS. Although it is present in normal serum, LBP is also induced as part of the acute phase response. Synthesis of LBP is though to be limited to the liver, but we have recently reported significant extrahepatic (including pulmonary) LBP mRNA expression in in vivo rat models of sepsis and inflammation. In the present study, we tested the hypothesis that a cellular source of pulmonary LBP in the rat may be vascular smooth muscle, by exposing cultured rat pulmonary artery smooth muscle cells (RPASMC) to cytokines and LPS. Treatment of RPASMC for 4 and 24 h with a combination of tumor necrosis factor alpha, interleukin 1 beta (IL-1 beta), interferon gamma, and LPS resulted in significant LBP mRNA expression. Of this mixture, IL-1 beta alone was sufficient to induce LBP mRNA expression in both a time- and dose-dependent manner. The effects of IL-beta on LBP mRNA expression were significantly antagonized by IL-1 receptor antagonist protein. Furthermore, supernatants from RPASMC treated with IL-1 beta enhanced the binding of [125I]ASD-LPS by the macrophage cell line RAW 264.7, indicative of LBP bioactivity. We conclude that pulmonary artery smooth muscle cells stimulated with IL-1 beta produce a transcript for LBP or a homologous product in vitro. Local production of LBP could play an important role in the pulmonary response to inflammation and sepsis.

Lipopolysaccharide binding protein participation in cellular activation by LPS

Lipopolysaccharide binding protein (LBP) is a plasma protein that plays an important intermediary role in host-endotoxin (LPS) interactions. LBP binds with high affinity to the lipid A portion of LPS and then interacts with the monocytic differentiation antigen CD14 to markedly up-regulate TNF-alpha production by mononuclear phagocytes. In the presence of LBP, 100-fold less LPS is required to trigger this cytokine response. LBP has been implicated in the interaction of LPS with both CD14+ (monocytes, macrophages, neutrophils) and CD14-cells (endothelial and epithelial cells) to promote such varying responses as secretion of cytokines and nitric oxide (NO), expression of adhesion molecules, production of tissue factor, and activation of neutrophils. Non-CD 14-bearing cells, such as endothelial cells, can also respond to LPS through this pathway via the soluble form of CD14, an interaction that is similarly enhanced by LBP. Recently, it has been proposed that LBP cannot only potentiate host responses to LPS but can also facilitate the neutralization of LPS under certain conditions. LBP has been described as acting as a lipoprotein transfer protein facilitating the transfer of LPS both to the target receptor (CD14) and lipoprotein (HDL).

Suppression of lipopolysaccharide-induced macrophage nitric oxide and cytokine production in vitro by a novel lipopolysaccharide antagonist

BACKGROUND

Many of the physiologic derangements resulting in septic shock are caused by inflammatory mediators such as nitric oxide (NO) and cytokines produced in response to bacterial endotoxin or, more specifically, lipopolysaccharide. The recent development of a novel class of lipopolysaccharide antagonists offers the opportunity to block this response selectively. In this article we investigated the ability of one of these antagonists, B464 (Eisai), to block lipopolysaccharide-induced release of macrophage NO and cytokines.

METHODS

The mouse macrophage cell line RAW264.7 was grown in vitro and exposed to (1) media control, (2) B464 alone, (3) lipopolysaccharide alone, or (4) lipopolysaccharide plus graded concentrations of B464. Supernatants were assayed for nitrite plus nitrate, the stable end products of NO, as well as tumor necrosis factor-alpha and interleukin-6. Total cellular RNA was examined for inducible NO synthase and interleukin-6 mRNA.

RESULTS

Lipopolysaccharide-stimulated increases in NO, tumor necrosis factor, and interleukin-6 production were blocked by B464. Reduction of NO was also seen at the level of inducible NO synthase mRNA. Induction of interleukin-6 mRNA was also suppressed.

CONCLUSION

B464 is a novel potent specific antagonist of lipopolysaccharide-induced macrophage NO and cytokine production.

Molecular cloning, characterization, and tissue distribution of rat lipopolysaccharide binding protein. Evidence for extrahepatic expression

LPS binding protein (LBP) is a glycoprotein present in normal serum that becomes markedly elevated during acute phase responses. LBP has been reported to greatly potentiate host responses to endotoxin or LPS. Therefore, LBP may play a critical role in the body's response to injury and infection. Little is known about the factors regulating production of LBP. To investigate the regulation of LBP expression, we have cloned the full-length cDNA for rat LBP. The deduced amino acid sequence of rat LBP was highly homologous with that reported for rabbit and human LBP. The sequence of rat LBP further refines the conserved regions found within the family of proteins that bind LPS; this family is comprised of bactericidal permeability-increasing protein and LBP from multiple species. Use of the rat LBP cDNA clone for Northern blot analysis reveals that LBP mRNA levels are markedly up-regulated in liver during acute phase responses. However, in contrast to previous reports, we also find evidence of extrahepatic expression of LBP under these induced conditions. The presence of LBP mRNA in activated tissues other than liver suggests that LBP may play a larger role in local tissue responses to LPS than previously appreciated.

Molecular cloning, characterization, and tissue distribution of rat lipopolysaccharide binding protein. Evidence for extrahepatic expression

LPS binding protein (LBP) is a glycoprotein present in normal serum that becomes markedly elevated during acute phase responses. LBP has been reported to greatly potentiate host responses to endotoxin or LPS. Therefore, LBP may play a critical role in the body's response to injury and infection. Little is known about the factors regulating production of LBP. To investigate the regulation of LBP expression, we have cloned the full-length cDNA for rat LBP. The deduced amino acid sequence of rat LBP was highly homologous with that reported for rabbit and human LBP. The sequence of rat LBP further refines the conserved regions found within the family of proteins that bind LPS; this family is comprised of bactericidal permeability-increasing protein and LBP from multiple species. Use of the rat LBP cDNA clone for Northern blot analysis reveals that LBP mRNA levels are markedly up-regulated in liver during acute phase responses. However, in contrast to previous reports, we also find evidence of extrahepatic expression of LBP under these induced conditions. The presence of LBP mRNA in activated tissues other than liver suggests that LBP may play a larger role in local tissue responses to LPS than previously appreciated.

Induction of hepatocyte lipopolysaccharide binding protein in models of sepsis and the acute-phase response

Lipopolysaccharide binding protein (LBP) is a serum glycoprotein that complexes with lipopolysaccharide (LPS) to facilitate macrophage response to endotoxin. To determine the conditions that stimulate LBP production in vivo, we measured the induction of LBP in models of inflammation produced by LPS, Corynebacterium parvum, and turpentine injection. Plasma aspartate aminotransferase and alanine aminotransferase concentrations and hepatocyte fibrinogen synthesis were elevated in all models. Northern blot analysis revealed 17-, 14-, and 20-fold upregulation of hepatocyte LBP mRNA following treatment with LPS, C parvum, and turpentine, respectively. Peritoneal macrophage interleukin 6 and tumor necrosis factor production following endotoxin stimulation was augmented by cultured hepatocyte supernatants, suggesting increased LBP synthesis in these groups. The results show that LBP mRNA is induced during hepatic inflammation and suggest that LBP is an acute-phase protein important in regulating the in vivo response to endotoxin.

Effect of folate supplementation on the incidence of dysplasia and cancer in chronic ulcerative colitis. A case-control study

Folate deficiency has been associated with dysplasia in human cancer models. Patients with ulcerative colitis commonly have decreased folate levels, which are partially due to sulfasalazine, a competitive inhibitor of folate absorption. To study the effect of folate supplementation on the risk of dysplasia or cancer (neoplasia) in ulcerative colitis, records from 99 patients with pancolitis for greater than 7 yr and enrolled in a surveillance program were reviewed. Thirty-five patients with neoplasia were compared with 64 patients in whom dysplasia was never found to determine the effect of folate supplementation on the rate of development of neoplasia using case-control methodology. At the time of the index colonoscopy, patients with neoplasia were older (43 +/- 11 vs. 39 +/- 12 yr) and had disease of longer duration (20 +/- 8 vs. 15 +/- 7 yr, p less than 0.05). Folate supplementation was associated with a 62% lower incidence of neoplasia compared with individuals not receiving supplementation (odds ratio, 0.38; 95% confidence interval, 0.12-1.20). There was no appreciable change in this effect when models were fit to adjust for sulfasalazine dose, duration of disease, age at symptom onset, prednisone dose, sulfa allergy, sex, race, or family history of colon cancer. The statistical power of the association between folate supplementation and neoplasia was 72%. Correction of risk factors before the development of neoplasia may prevent this serious complication. Pending a larger case-control study, folate supplementation during sulfasalazine administration is recommended to possibly prevent the complication of dysplasia or cancer in ulcerative colitis.