Evaluation of Arthrocentesis with hyaluronic acid injections for management of temporomandibular disorders: a systematic review and case series.

Although arthrocentesis is an accepted safe treatment modality for the management of temporomandibular disorders (TMD) in symptomatic patients, the benefit of hyaluronic acid (HA) injections remains uncertain. The aim of this study was to evaluate whether intra-articular HA injections adjunctive to arthrocentesis can be more effective than other medications for the improvement of TMD associated symptoms. Additionally, the impact of HA injections on quality of life of TMD patients was assessed with SF-36® questionnaire in a cohort of patients. An electronic search of Medline, Scopus and Cochrane databases was performed up to March 2020. The following search terms were used: "arthrocentesis", "hyaluronic acid", "intra-articular injections", "visco-supplementation", "temporomandibular disorders". Prospective and retrospective studies that reported the application of HA injections compared to other intra-articular drugs for the treatment of temporomandibular disorders were included. Systematic or narrative reviews and pre-clinical studies were excluded. Additionally, a retrospective clinical study was performed for evaluation of changes in quality of life before and after arthrocentesis with HA injections. In the systematic review, the initial search yielded 1327 articles. After screening of the titles, abstracts, and full texts, 29 studies were selected (26 randomized studies, 2 controlled clinical trials, 1 retrospective report). In the clinical study, 12 patients were included. Intra-articular injections of HA and other medications together with arthrocentesis seemed to be beneficial for improvement of functional symptoms of TMD and pain. The case series also supported the efficacy of HA injections showing an improvement of quality of life of these patients. However, from literature review, it was impossible to identify an optimum drug or a protocol for predictably improving the pain and/or functional symptoms of temporomandibular problems, due to different etiologies, diversity of treatment modalities and conflicting results. In conclusion, there is no consensus in the literature that HA injections shows better results in comparison with other treatment modalities. According to the results of the present clinical study, HA injections with/without arthrocentesis seems to be beneficial in terms of clinical symptoms and quality of life of the TMD patients.

Dental implant survival rate in irradiated and non-radiated patients: a systematic review and meta-analysis.

Radiotherapy to head and neck has always been considered as a risk factor for rehabilitation with dental implants. Nevertheless, recent data suggest that overall, 5-year implant survival in irradiated patients can be greater than 90%. The purpose of this review was to compare the implant survival rates of irradiated and non-radiated head and neck cancer sites, and discuss the outcomes, through a systematic review approach of prospective and retrospective studies. Electronic searches were performed in the EMBASE, Cochrane, and PubMed/Medline databases up to 2019 Dec, to identify retrospective and prospective clinical studies addressing the subject. This systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The primary variables collected from the studies were the site of tumor, age and sex of the patient, site of implant placement, radiation dosage, frequency and duration of radiotherapy, follow-up duration, implant survival and stability, hard and soft tissue changes after implant placement, any type of biological and mechanical complication, and oral health quality of life (QOL). Fifteen studies including 1097 patients and a total of 4637 implants placed in irradiated and non-irradiated sites, with a follow up duration varying from 6 to 120 months, were selected for the systematic review. The results of the quantitative synthesis suggested statistically significantly better survival rate of implants placed in nonradiated sites, as compared to irradiated sites (p<0.00001). However, the cumulative survival rates over a period of 7-10 years were reported to be comparable. Quality of life (QOL) after implant rehabilitation was not found to be significantly different between the compared groups. Due to the limited number of information, insufficient data was available to draw conclusion on peri-implant complication rate. No relationship was found between age, gender, and implant survival rates. Implant placement in irradiated sites is challenging and often warrants protocol modifications. Although statistically the survival rates at irradiated sites were lower in comparison to non-radiated sites, a strict inclusion criterion in patient selection, timing of implant placement after radiotherapy, radiation dosage and regular oral hygiene maintenance could minimize the chances of implant failure in irradiated patients.

Clinical efficacy of grape seed extract as an adjuvant to scaling and root planing in treatment of periodontal pockets.

Grape seed extract (GSE), a naturally producing polyphenolic compound, is found to be a potent hostmodulatory agent and considered for management of periodontal disease. Its anti-bacterial, antioxidant, and anti-inflammatory property may aid in achieving periodontal health. To assess the clinical efficacy of GSE in adjunct to scaling and root planing (SRP) in healing of periodontal pockets. The present study was a longitudinal, parallel design, randomized clinical trial. Seventy-two patients (mean age 39.2±8.6 years) with periodontal pockets were randomly divided into two groups; Test group received intra-pocket delivery of GSE with SRP and Control group received SRP alone. The clinical parameters like Plaque Index (PI), Gingival Index (GI), Probing Depth (PD) and Relative Attachment Level (RAL) were recorded at baseline and 3 months. 64 patients completed the study. Test group at the end of 3 months had statistically significant reduced PD (p=0.002) and RAL (p=0.01). No significant difference was observed for PI and GI at the end of 3 months. Intra-pocket application of GSE with SRP could be beneficial in management of periodontal pockets.

Optical coherence tomography application for assessing variation in bone mineral content: a preclinical study.

OBJECTIVE: Optical Coherence Tomography (OCT) is a non-invasive imaging technique that produces cross-sectional images through biological tissues, allowing three-dimensional reconstruction and analysis. Aim was to evaluate if OCT may discriminate among tissues with different bone density and composition, by measuring the depth of light penetration in porcine and rat bone samples. MATERIALS AND METHODS: Two carpal bone samples (2 cm length) were harvested from the porcine forelimb and fixed overnight in 3.7% buffered formal saline. Following fixation, one sample was decalcified in a 1:1 mixture of 8% hydrochloric acid and 8% formic acid solution for three days, with solution changes each day. Samples were imaged using an OCT microscope. Furthermore, the calvaria, ulnar, alveolar and basal bone of the mandible of 6 male and 6 female rats were cleared of overlying soft tissues and scanned under OCT. The light penetration depth in each sample was measured using the software Image J, and Scattering Attenuation Microscopy. RESULTS: In the mineralized bone the average depth (µm) and standard deviation (SD) of light penetration were 790.1±18.05 and 410.4±21.7 for periosteal and endosteal surface, respectively, and 507.3±21.03 for cross-section surfaces, while it was 858.4±32.03 for periosteal surface, 1150±26.9 for endosteal, and 627.3±31.8 for cross-section bone surfaces in demineralized porcine bone. There was a significant difference (p<0.001) in depth of light penetration between normal and de-mineralized bone for all regions evaluated. No systematic significant difference in light penetration depth between-gender was found at any site evaluated, while there were variations between sites (p<0.001). The OCT detected differences in bone mineral and porosity among gender (p<0.0001) CONCLUSIONS: This study suggests that OCT may represent a valuable technique to estimate local variations in bone mineral content.

Clinical and histopathological profile of oral cancer: a quadrennial analysis of Regional Cancer Centre of Odisha, India.

OBJECTIVE: To contribute toward the identification of population-based clinical and histopathological profile of oral squamous cell carcinoma (OSCC), this study was undertaken at the Regional Cancer Centre of Odisha (AHRCC), India. PATIENTS AND METHODS: This retrospective study included all patients diagnosed with OSCC registered at AHRCC, Odisha from 1st January 2015 to 31st December 2018. Demographic, clinical, and pathological data of each patient were retrieved from patient records. Patients with incomplete records were excluded. No postoperative treatment details were collected. RESULTS: The study included 851 cases of OSCC with the mean age of the population found to be 53.8±14.2 years. Male to female ratio was found to be 2.18:1. Gingivobuccal complex was the most common site of OSCC. While 679 patients were reported to undergo incision biopsy only 172 patients underwent excision biopsy in four years. Well differentiation (n=782) is the most common histological grading. The median clinical size of the tumour was 4 cm. Upon analyzing histological parameters in excision specimens lymphovascular and perineural invasion were seen in 38 and 26 cases, respectively. Cervical lymph node metastasis was seen in 42 cases out of 172 excision specimens (24%). 63.23% of cases presented with a depth of invasion between 5 to 10 mm. CONCLUSIONS: This is the largest comprehensive data from the regional cancer center of Odisha population which highlights the demographic, clinical, and histopathological data reported to date.

Congenital aural atresia treated with floating mass transducer on the round window: 5 years of imaging experience.

PURPOSE: The aim of this paper is to illustrate imaging features of patients affected by congenital aural atresia (CAA) before and after treatment with a Vibrant SoundBridge (VSB) device implanted on the round window. MATERIALS AND METHODS: Ten patients (5 males and 5 females; mean age 22.1 years) with CAA underwent preoperative high-resolution computed tomography (HRCT) to estimate the degree of involvement of the middle- and inner-ear structures and highlight radiological landmarks useful for surgical planning. RESULTS: Bilateral CAA, mostly of the mixed type, was present in 7 patients and ossicular chain abnormalities in 16 ears (94% of cases). The round window region was normal in all patients, whereas facial-nerve course and/or caliber abnormalities were present in 6 ears (35.3%). The tympanic cavity was small in 13 ears (76.5%), whereas the mastoid was well pneumatized in 8/17 (47%). CONCLUSIONS: HRCT provides accurate information about anatomy and malformations of the middle and inner ear and can thus assist the surgeon in planning the procedure.

Novel method of fitting of children with auditory brainstem implants.

OBJECTIVES: To develop a reliable and objective fitting method for use with young children with an auditory brainstem implant (ABI). MATERIALS AND METHODS: Subjects were 17 young children implanted with an ABI with the mean age 2 years and 4 months (8-64 months). Evoked auditory brainstem response (eABR) measurements were performed intraoperatively and at activation in order to record the auditory response and non-auditory side effects. Each child was tested to observe any subjective responses to the electric stimuli and non-auditory side effects. All children were fitted based on the postoperative eABR. The minimum follow up time was 12 months. RESULTS: Intraoperatively an eABR could be obtained in all children. The responses were recordable from 75-100% of all electrodes. At initial stimulation eABR were recordable in all children. The eABR was obtained in 79.7% of all electrodes (25-100%) with a mean eABR threshold of 22.3 nC. eABR without any non-auditory stimulation was recorded on all electrodes in 11 children. Mixed eABR and non-auditory responses were recorded on 2-6 electrodes in 6 children. The subjective auditory responses for at least 1 electrode were noted in 15 children. In the 2 remaining cases the auditory response was obtained only when the device was activated. In all children the subjective responses were within the estimated dynamic range for each electrode. Each child was able to accept up to 100% of volume of the created map. The non-auditory response was observed only on children and electrodes with mixed eABR and non-auditory responses. The mean CAP score at 6 months after the activation was 2.4 (1-4). CONCLUSIONS: eABR seems to be a reliable tool to judge ABI electrode placement and a reliable method for fitting of young children with an ABI. The data suggest that eABR-based fitting helps children to more quickly achieve auditory perception and development.

Role of tumor necrosis factor-alpha in the pathophysiologic alterations after hepatic ischemia/reperfusion injury in the rat.

Cytokines are recognized as critical early mediators of organ injury. We attempted to determine whether or not severe hepatic ischemia/reperfusion injury results in tumor necrosis factor-alpha (TNF-alpha) release with subsequent local and systemic tissue injury. After 90 min of lobar hepatic ischemia, TNF was measurable during the reperfusion period in the plasma of all 14 experimental animals, with levels peaking between 9 and 352 pg/ml. Endotoxin was undetectable in the plasma of these animals. Pulmonary injury, as evidenced by a neutrophilic infiltrate, edema and intra-alveolar hemorrhage developed after hepatic reperfusion. The neutrophilic infiltrate was quantitated using a myeloperoxidase (MPO) assay; this demonstrated a significant increase in MPO after only 1 h of reperfusion. Anti-TNF antiserum pretreatment significantly reduced the pulmonary MPO after hepatic reperfusion. After a 12-h reperfusion period, there was histologic evidence of intra-alveolar hemorrhage and pulmonary edema. Morphometric assessment showed that pretreatment with anti-TNF antiserum was able to completely inhibit the development of pulmonary edema. Liver injury was quantitated by measuring serum glutamic pyruvic transaminase which showed peaks at 3 and 24 h. Anti-TNF antiserum pretreatment was able to significantly reduce both of these peak elevations. These data show that hepatic ischemia/reperfusion results in TNF production, and that this TNF is intimately associated with pulmonary and hepatic injury.

Chemokine expression during hepatic ischemia/reperfusion-induced lung injury in the rat. The role of epithelial neutrophil activating protein.

The liver is highly susceptible to a number of pathological insults, including ischemia/reperfusion injury. One of the striking consequences of liver injury is the associated pulmonary dysfunction that may be related to the release of hepatic-derived cytokines. We have previously employed an animal model of hepatic ischemia/reperfusion injury, and demonstrated that this injury causes the production and release of hepatic-derived TNF, which mediates a neutrophil-dependent pulmonary microvascular injury. In this study, we have extended these previous observations to assess whether an interrelationship between TNF and the neutrophil chemoattractant/activating factor, epithelial neutrophil activating protein-78 (ENA-78), exists that may be accountable for the pathology of lung injury found in this model. In the context of hepatic ischemia/reperfusion injury, we demonstrated the following alterations in lung pathophysiology: (a) an increase in pulmonary microvascular permeability, lung neutrophil sequestration, and production of pulmonary-derived ENA-78; (b) passive immunization with neutralizing TNF antiserum resulted in a significant suppression of pulmonary-derived ENA-78; and (c) passive immunization with neutralizing ENA-78 antiserum resulted in a significant attenuation of pulmonary neutrophil sequestration and microvascular permeability similar to our previous studies with anti-TNF. These findings support the notion that pulmonary ENA-78 produced in response to hepatic-derived TNF is an important mediator of lung injury.

The application of visible absorption spectroscopy to the analysis of uranium in aqueous solutions.

Through assay analysis into an excess of 1M H2SO4 at fixed temperature a technique has been developed for uranium concentration analysis by visible absorption spectroscopy over an assay concentration range of 1.8-13.4mgU/g. Once implemented for a particular spectrophotometer and set of spectroscopic cells this technique promises to provide more rapid results than a classical method such as Davies-Gray (DG) titration analysis. While not as accurate and precise as the DG method, a comparative analysis study reveals that the spectroscopic method can analyze for uranium in well characterized uranyl(VI) solution samples to within 0.3% of the DG results. For unknown uranium solutions in which sample purity is less well defined agreement between the developed spectroscopic method and DG analysis is within 0.5%. The technique can also be used to detect the presence of impurities that impact the colorimetric analysis, as confirmed through the analysis of ruthenium contamination. Finally, extending the technique to other assay solution, 1M HNO3, HCl and Na2CO3, has also been shown to be viable. Of the four aqueous media the carbonate solution yields the largest molar absorptivity value at the most intensely absorbing band, with the least impact of temperature.

Tumor necrosis factor-alpha gene expression in human whole blood.

Tumor necrosis factor-alpha (TNF) is recognized as a principal mediator of a variety of pathophysiologic and immunologic events. Lipopolysaccharide (LPS) challenge, either in vitro or in vivo, results in significant TNF production. In this study we present data demonstrating LPS-induced TNF mRNA expression and bioactivity using an in vitro tissue system of whole blood (WB). The kinetics of LPS-induced TNF production by WB was significantly accelerated as compared to isolated cultured peripheral blood monocytes (PBM). At post-LPS challenge, plasma from WB demonstrated a rapid rise in TNF bioactivity, peaking by 4 hr (1,021 units/ml/10(6) cells), plateauing between 4 and 8 hr, and then decreasing over the next 16 hr. In contrast, the highest measured TNF bioactivity from PBM did not occur until the 24-hr time-point (175 units/ml/10(6) cells). Whole blood buffy-coat TNF mRNA was assessed by Northern blot analysis, and demonstrated significant TNF mRNA accumulation at 1 hr and a peak 2 hr post-LPS challenge. By 8 hr TNF mRNA was undetectable. Concomitant administration of LPS with either prostaglandin E2 (10(-6)M) or Dexamethasone (10(-6)M) resulted in significant suppression of LPS-induced TNF production. This data supports WB as a useful in vitro medium for the molecular and cellular analysis of TNF. As specialized connective tissue, WB may provide an important environment to study the pharmacologic manipulation of TNF mRNA and bioactivity.

Hyperacute rejection in porcine liver transplantation. I. Clinical characteristics, histopathology, and disappearance of donor-specific lymphocytotoxic antibody from serum.

Hyperacute rejection following orthotopic liver transplantation remains an extremely unusual occurrence. In this study, we examined a porcine model of liver transplantation in which recipient animals were sensitized prior to transplantation with three serial full-thickness skin grafts. Three experimental groups were studied. Group I recipients (n = 6) were specifically sensitized against their liver donors with biweekly skin grafts followed by hepatic grafting. Group II recipients (n = 6) underwent third-party skin graft sensitization prior to liver transplantation. Group III recipients (n = 6) underwent liver grafting without sensitization. Mixed lymphocyte cultures were done before each skin graft and prior to transplantation. Lymphocytotoxic antibody (LCTA) titers were measured before the first skin graft, at weekly intervals thereafter, intraoperatively, and daily postoperatively until death. Intraoperative and postmortem liver biopsies were obtained in all recipients. Five of six recipients in Group I died within 4 hr of hepatic revascularization. The remaining animal survived for four days. Mean survival time in group I was 0 +/- 0.7 days. In contrast, MST in groups II and III were 4.0 +/- 1.2 and 6.2 +/- 1.3 days, respectively. The MST in group I was significantly shorter than in groups II and III (P less than 0.026 and P less than 0.005, respectively). There was no significant difference in survival between groups II and III. MLC reactivity between recipients and skin donors increased progressively following each skin graft, reaching a peak just prior to liver transplantation. LCTA titers also increased following each skin graft, reaching peak levels immediately prior to hepatic grafting. Intraoperative LCTA titers decreased within 2 min of graft revascularization and were undetectable within 4 hr. In group III (unsensitized recipients), MLC reactivity was low and at no time was LCTA detectable. Histologic examination of the livers from group I recipients showed parenchymal hemorrhage, endophlebitis, and neutrophil infiltration. Histologic examination of postmortem liver biopsies from animals in groups II and III revealed acute cellular rejection. In conclusion, hyperacute rejection resulting in graft failure and recipient death can be consistently produced in a porcine model of hepatic transplantation by donor-specific sensitization of the recipient. It is postulated that high titers of donor-specific antibody are required to exceed the liver's capacity for antibody absorption and elimination and produce the clinical picture of hyperacute rejection.

Mechanisms of hyperacute rejection in porcine liver transplantation. Antibody-mediated endothelial injury.

Hyperacute rejection after OLT is an unusual event. We have demonstrated previously that hepatic hyperacute rejection can occur in the presence of high titers of donor-specific cytotoxic antibody. This study addresses the issues of antibody localization within the allograft and the consequences of antibody deposition and complement activation within the transplanted organ. A porcine model of liver transplantation was used and 3 experimental groups were studied. Group I recipients (n = 6) were specifically sensitized to their liver donors with skin grafts from their liver donors before hepatic grafting. Group II recipients (n = 6) underwent third-party skin graft sensitization before liver transplantation. Group III recipients (n = 6) underwent liver grafting without prior sensitization. After liver transplantation, serum complement (CH50) levels declined promptly in all groups; a statistically significant drop as compared with control animals was seen only in group I (P < 0.05). Liver biopsies from donor-specific sensitized recipients showed massive injury by light microscopy within 30 min of revascularization, demonstrating fibrinoid necrosis of vessels and neutrophil influx. On immunofluorescent examination, liver specimens from donor-specific sensitized animals showed intense IgG, IgM, and C3 deposition in the vessels of the portal triads. Antibody deposition was not seen in third-party sensitized animals or control animals. On electron microscopy, control animals and third-party sensitized animals showed minimal ultrastructural alterations. In comparison, livers from donor-specific sensitized animals showed severe microvascular injury with destruction of endothelial cells, edema, hemorrhage, and hepatocyte necrosis. In a passive serum transfer experiment carried out by infusing serum from a skin graft-sensitized pig directly into the portal vein of the skin graft donor, severe liver injury was evident, with identification of antibody deposition by light and electron microscopy and by immunofluorescence. These studies demonstrate that tissue injury in hyperacute hepatic rejection is mediated by antibody deposition within the grafted liver and is associated with systemic activation of the complement cascade.

The production of tumor necrosis factor alpha and the development of a pulmonary capillary injury following hepatic ischemia/reperfusion.

The large mass of fixed macrophages resident in the liver make it a potentially rich source of cytokines. We have previously demonstrated that an isolated and severe ischemia/reperfusion injury to the liver results in cytokine release, specifically tumor necrosis factor alpha, and that TNF is then involved in the development of pulmonary pathology. This study was designed to determine the kinetics of TNF release following varying periods of hepatic ischemia and to further investigate the acute lung injury that follows. Suprahepatic blood samples were obtained at serial time points following a 45-, 60-, 75-, or 90-min ischemic insult to a segment of the rat liver with subsequent reperfusion. Using a bioassay based on the WEHI 164 cell line, plasma TNF levels were measured in all experimental animals; sham-operated control animals had undetectable levels. Changes in pulmonary capillary permeability were then measured using a standard 125I-labeled albumin washout technique following a 90-min ischemic insult with subsequent reperfusion. A significant increase in the mean permeability index was observed 9 to 12 hr following hepatic reperfusion (.601 +/- 102 as compared with .114 +/- .085 in sham-operated controls, P less than 0.005). Animals treated with anti-TNF antiserum prior to the induction of hepatic ischemia had a significantly reduced pulmonary capillary leak compared to animals pretreated with rabbit serum without TNF-blocking properties (.184 +/- .029 versus .694 +/- 052 for the control serum, P less than 0.005). TNF release follows both moderate and severe ischemic injury to the liver and the results reported here implicate TNF as an important mediator of increased pulmonary capillary permeability. These experiments confirm previous histologic studies that demonstrated pulmonary edema and intra-alveolar hemorrhage following hepatic ischemia/reperfusion, with subsequent blockade of the histologic injury by pretreatment with anti-TNF antiserum.

Identification of a new non-neuronal cell type in rat olfactory epithelium.

We have examined adult and embryonic rat olfactory epithelia by immunohistochemical techniques using the monoclonal antibody 1A-6, which was raised against embryonic rat olfactory epithelia. A heretofore unidentified cell type, reactive with the monoclonal antibody 1A-6, was observed scattered within the epithelium. The 1A-6 reactivity of these cells is most intense on the microvilli projecting from the luminal cell surfaces. For several reasons, we believe these cells are not neurons but a distinct subpopulation of supporting cells or some other sort of non-neuronal cells. (1) They have no identifiable axonal process, are not reactive with an antibody against olfactory marker protein, and are not in juxtaposition with trigeminal axons. (2) They survive ablation of the olfactory bulb. (3) Their nuclei lie within the supporting cell layer, and they resemble supporting cells morphologically and in their [3H]thymidine birthdating and turnover characteristics. However, the 1A-6-positive cells fail to react with the general supporting cell-specific monoclonal antibody SUS-1 [see Hempstead J. L. and Morgan J. I. (1983) Brain Res. 188, 289-295] a finding which suggests that they are not typical supporting cells. Immunoreactivity to 1A-6 is developmentally regulated. Immunohistochemical preparations of almost all tissues we examined showed widespread reactivity in the embryo but a much more restricted pattern in the adult. In the olfactory epithelium of the fetus, the luminal surfaces of all cells, including supporting cells and olfactory receptor cells and cilia, are reactive, while in the adult only the non-neuronal cell subpopulation shows this reactivity. We also found that during the reconstitution of olfactory epithelium which occurs in response to olfactory bulbectomy-induced neuronal degeneration, fetal patterns of 1A-6 reactivity are not re-expressed, i.e. the only 1A-6-positive cells are the non-neuronal cells seen in unperturbed adult olfactory epithelium. Preliminary biochemical analyses of membrane fractions from E19 brain and from adult olfactory mucosa indicate that the 1A-6 reactivity is associated with two bands, having molecular weights of 42,000 and 46,000 on Western blots.

Lung and liver injury following hepatic ischemia/reperfusion in the rat is increased by exogenous lipopolysaccharide which also increases hepatic TNF production in vivo and in vitro.

Hepatic ischemia/reperfusion (I/R) results in tumor necrosis factor (TNF) release. Kupffer cells (KC) are one source of this TNF. This study investigates the effects of hepatic I/R combined with lipopolysaccharide (LPS) on the lung and liver injury that follow hepatic I/R and on hepatic release of TNF, epithelial neutrophil activating protein (ENA-78), and macrophage inflammatory protein-2 (MIP-2). The effects of these experimental conditions on TNF production by primary rat KC in vitro were also investigated. Rats were subjected to hepatic I/R alone, hepatic I/R + LPS, sham laparotomy alone, or sham laparotomy + LPS and pulmonary MPO, pulmonary microvascular permeability, hepatic neutrophil influx, hepatic injury, and hepatic TNF, ENA-78, and MIP-2 production were measured. These experiments demonstrated that hepatic I/R in conjunction with LPS results in a more severe lung and liver injury and increased hepatic TNF, ENA-78, and MIP-2 release. The effects of these experimental conditions on rat KC TNF production demonstrated that hepatic I/R + LPS results in a more significant release of TNF as compared to LPS alone or I/R alone. Hepatic I/R plus LPS results in a more severe lung and liver injury and is likely secondary to a more significant and prolonged release of TNF by KC. This may provide a mechanism for development of multiple organ system failure in some patients undergoing hepatic resection, hepatic transplantation, complex vascular operations, or in the setting of hypovolemic shock. Portal endotoxemia related to mesenteric venous congestion or other systemic insults may have a significant impact on post-operative complications and recovery in the setting of a local or global hepatic I/R injury.

Post-ischemic shunt following hepatic ischemia/reperfusion does not affect tissue chemokine levels of tissue injury.

Hepatic ischemia followed by reperfusion causes the release of a cascade of mediators, including tumor necrosis factor-alpha and epithelial neutrophil activating protein (ENA-78), which are important in the subsequent development of the lung and liver injury associated with this insult. We hypothesize that preferential post-ischemic shunting of blood into the nonischemic hepatic lobes at the time of reperfusion may increase the ischemic injury. To test this hypothesis, we utilized a rat model of lobar no-flow hepatic ischemia/reperfusion and removed the nonischemic hepatic lobes at the time of reperfusion to eliminate the preferential shunting of blood into the nonischemic tissues. We assessed pulmonary and hepatic tissue levels of ENA-78, pulmonary neutrophil influx and changes in pulmonary capillary permeability, and liver injury as measured by hepatic neutrophil influx and serum transaminase levels. Our results demonstrated that there were no significant differences in pulmonary and hepatic levels of ENA-78, or in the development of the lung and liver injury in animals undergoing resection of the nonischemic hepatic lobes at the time of reperfusion, as compared with animals undergoing hepatic ischemia/reperfusion alone.

Hepatic inflammation following 70% hepatectomy may be related to up-regulation of epithelial neutrophil activating protein-78.

Tumor necrosis factor-alpha (TNF) is known to be released after partial hepatectomy. Furthermore, TNF triggers the release of chemotactic cytokines, such as epithelial neutrophil activating protein (ENA-78), which are important for neutrophil chemotaxis, activation, and propagation of the inflammatory response. We now postulate that ENA-78 may play a role the hepatic inflammatory response that occurs following partial hepatectomy. Rats were subjected to 70% hepatectomy or sham laparotomy and were killed in a time-dependent manner. Hepatic neutrophil influx, as assessed by myeloperoxidase (MPO) levels, serum alanine aminotransferase (ALT), and hepatic TNF and ENA-78 levels, as measured by ELISA, were evaluated at 1, 6, and 12 h following operation. MPO levels became significantly elevated within 6 h of hepatectomy and remained elevated at 12 h. Serum ALT became significantly elevated within 1 h of hepatectomy and continued to rise at 12 h. Hepatic TNF and ENA-78 were also increased significantly after hepatectomy. Next, rats undergoing 70% hepatectomy were treated with neutralizing anti-ENA-78 serum; this resulted in a significant decrease in hepatic MPO and serum ALT, suggesting less hepatic injury. To determine whether ENA-78 release was induced by TNF is this model, rats were treated with neutralizing anti-TNF serum and hepatic ENA-78 levels measured 6 h posthepatectomy. ENA-78 levels were significantly decreased in the animals receiving the anti-TNF serum, suggesting that ENA-78 is released in response to TNF in this model. These data suggest that TNF triggers the release of ENA-78 following 70% hepatectomy and that ENA-78 contributes to the hepatic neutrophil influx and liver injury following 70% hepatectomy.

Proliferative effects of CXC chemokines in rat hepatocytes in vitro and in vivo.

The CXC chemokines have well-documented neutrophil chemotactic, angiogenic, and mitogenic properties. The current investigations evaluate the effects of interleukin-8 (IL-8), epithelial neutrophil activating protein (ENA-78), and macrophage inflammatory peptide-2 (MIP-2) on hepatocyte proliferation in vitro and liver regeneration in vivo. Primary rat hepatocytes were isolated by collagenase digestion and exposed to incremental doses of IL-8, ENA-78, or MIP-2, and cellular proliferation was measured via tritiated thymidine incorporation. These experiments demonstrated significant increases in hepatocyte proliferation in response to IL-8, ENA-78, and MIP-2. Next, rats were sacrificed in a time-dependent manner following 70% hepatectomy or sham laparotomy, and hepatic tissue levels of MIP-2 and ENA-78 were measured using an ELISA. ENA-78 and MIP-2 were significantly elevated following 70% hepatectomy as compared with sham-operated control animals. Rats undergoing 70% hepatectomy were then treated with neutralizing anti-ENA-78 serum, anti-MIP-2 serum, or preimmune control serum, and liver regeneration was evaluated. These experiments demonstrated that neutralization of ENA-78 or MIP-2 slowed the rate of liver regeneration. These data suggest that the CXC chemokines may be important agents for the induction of hepatocyte proliferation and may be important molecules in vivo in the setting of liver injury, repair, and regeneration.

Tumor necrosis factor up-regulates intercellular adhesion molecule 1, which is important in the neutrophil-dependent lung and liver injury associated with hepatic ischemia and reperfusion in the rat.

Tumor necrosis factor (TNF) is released during hepatic ischemia/reperfusion (I/R) and plays an important role in the ensuing neutrophil-mediated lung and liver injury. Since TNF is not a direct neutrophil chemotaxin, we hypothesized that TNF may up-regulate neutrophil adhesion molecules, specifically intercellular adhesion molecule-1 (ICAM-1), following hepatic I/R, and that this molecule then plays an important role in tissue neutrophil influx. Rats underwent 90 min of lobar hepatic ischemia with reperfusion. Pulmonary and hepatic ICAM-1 expression were assessed by reverse transcription-polymerase chain reaction, Western blot analysis, and immunohistochemical staining. Increases in hepatic ICAM-1 were demonstrated within 1 h of reperfusion, while increases in pulmonary ICAM-1 were not seen until 6 h of reperfusion. Next, rats were treated with anti-TNF antibody or control antibody without TNF neutralizing properties prior to hepatic I/R. Pretreatment with anti-TNF antibody significantly decreased pulmonary and hepatic ICAM-1 expression after hepatic I/R. We next investigated the effects of pretreatment with anti-ICAM-1 antibodies on the lung and liver injury that follows hepatic I/R. Lung injury was assessed by changes in pulmonary capillary permeability as estimated by extravasation of Evans Blue dye and pulmonary neutrophil influx as measured by lung myeloperoxidase levels. Liver injury was assessed by hepatic neutrophil morphometrics and plasma liver enzymes (alanine aminotransferase). Pretreatment with anti-ICAM-1 antibodies significantly decreased pulmonary capillary permeability, pulmonary myeloperoxidase, hepatic neutrophil influx, and plasma alanine aminotransferase, as compared to animals pretreated with control antibody. These data suggest that TNF is a proximal trigger for pulmonary and hepatic ICAM-1 up-regulation following hepatic ischemia with reperfusion, and that ICAM-1 is important for pulmonary and hepatic neutrophil influx, with the resultant tissue injury, following hepatic I/R.