Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
1.
Arthroscopy ; 40(1): 176-186, 2024 01.
Article in English | MEDLINE | ID: mdl-37355192

ABSTRACT

PURPOSE: To systematically review the current literature on the effectiveness of hip arthroscopy simulation training and to determine the consistency of reporting and validation of simulation used in hip arthroscopy. METHODS: Three databases (PubMed, EMBase, and CINAHL) were screened using PRISMA guidelines in January 2022 for published literature on virtual simulation in hip arthroscopy. Studies reporting on the use of hip arthroscopy simulation training in orthopedic surgical trainees were included and assessed for quality and risk of bias using MINORS criteria. The number of participants, participant education level, experience, simulator type, validation type, method of assessment, and simulation outcomes were extracted from included studies. RESULTS: Of the 286 articles screened, 11 met inclusion criteria for review evaluating 323 orthopedic trainees with a mean of 29.36 participants per study published between 2012 and 2021, most commonly in the United Kingdom (55%). The four most reported surgical skills evaluated were visualization and probing tasks (82%), mean time to perform the task (73%), number of cartilage and soft tissue collisions (73%), and number of hand movements (73%). The most described measurement instruments included a simulation built-in scoring system (55%), Arthroscopic Surgical Skill Evaluation Tool (ASSET) Global Rating Scale (GRS) (27%), and motion analysis system (18%). Construct validity was the most reported overall type of validity (82%), followed by face validity (36%), transfer validity (18%) and content validity (18%). Construct validity was also the most reported validity for the simulator and measurement instrument (55% and 89%, respectively). CONCLUSIONS: There is significant variation in reported learning outcomes and measurement instruments for evaluating the effectiveness of hip arthroscopic-based education. This study highlights that simulation training may be an effective tool for evaluation of hip arthroscopy skills. LEVEL OF EVIDENCE: Level III, systematic review of level I to III studies.


Subject(s)
Orthopedics , Simulation Training , Humans , Arthroscopy/education , Clinical Competence , Orthopedics/education , Computer Simulation
2.
Orthop J Sports Med ; 9(5): 23259671211001773, 2021 May.
Article in English | MEDLINE | ID: mdl-33997073

ABSTRACT

BACKGROUND: Surgical management of unstable distal clavicle fractures (DCFs) remains controversial. Traditional open techniques result in acceptable union rates but are fraught with complications. In response to these limitations, arthroscopic techniques have been developed; however, clinical outcome data are limited. PURPOSE: The primary purpose was to systematically evaluate the clinical and radiographic outcomes of arthroscopic fixation of unstable DCFs. The secondary purpose was to characterize the overall complication rate, focusing on major complications and subsequent reoperations. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: A systematic review of the literature was performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and included a search of the PubMed, Web of Science, Cochrane Register of Controlled Trials, EMBASE, and Scopus databases. English-language studies between 2008 and 2019 that reported on outcomes of patients with DCFs who underwent operative fixation using an arthroscopic or arthroscopically assisted surgical technique were included. Data consisted of patient characteristics, fracture type, surgical technique, concomitant injuries, union rates, functional outcomes, and complications. RESULTS: A total of 15 studies consisting of 226 DCFs treated using an arthroscopically based technique were included in the systematic review. The majority of fractures were classified as Neer type II. Most (97%) of the fractures underwent arthroscopic fixation using a cortical button coracoclavicular stabilization surgical technique. Bony union was reported in 94.1% of the fractures. Good to excellent outcomes were recorded in most patients at the final follow-up. The Constant-Murley score was the most widely used functional outcome score; the pooled mean Constant score was 93.06 (95% CI, 91.48-94.64). Complications were reported in 14 of the 15 studies, and the overall complication rate was 27.4%. However, only 12% of these were considered major complications, and only 6% required a reoperation for hardware-related complications. CONCLUSION: Arthroscopic fixation of DCFs resulted in good functional outcomes with union rates comparable to those of traditional open techniques. While the overall complication profile was similar to that of other described techniques, there was a much lower incidence of major complications, including hardware-related complications and reoperations.

3.
Foot Ankle Clin ; 26(1): 187-203, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33487240

ABSTRACT

In athletes, foot injuries present with a variety of mechanisms, severity, and implications for return to play. Although potentially given less attention than knee and shoulder injuries by the team physician, foot injuries are common and thus require knowledgeable consideration. In this article, we review the anatomy, presentation, workup, and management of several of the most common athletic foot injuries, including turf toe, Lisfranc injuries, Jones fractures, and navicular stress fractures. The goal is to provide the team physician with the information necessary to evaluate and manage these injuries on the sideline and in the training room.


Subject(s)
Athletic Injuries , Foot Injuries , Fractures, Bone , Sports , Athletic Injuries/diagnosis , Athletic Injuries/therapy , Foot Injuries/diagnosis , Foot Injuries/therapy , Humans , Seasons
4.
J Shoulder Elbow Surg ; 30(1): 151-157, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33317701

ABSTRACT

BACKGROUND: The American Shoulder and Elbow Surgeons (ASES) Standardized Shoulder Assessment Form is one of the most frequently used outcomes score for shoulder pathology. The patient report section of the ASES questionnaire (p-ASES) is easy to complete, can be quickly administered, and is applicable to a wide range of shoulder pathologies, yet a validated Spanish translation of this questionnaire does not currently exist for diverse Spanish-speaking populations. The purpose of this study was to translate and culturally adapt the patient report section of the ASES to Spanish and to assess its validity and reliability among a culturally diverse group of Spanish-speaking patients, typically seen in the United States. METHODS: The p-ASES Standardized Shoulder Assessment Form was translated into Spanish using a universal approach for translation and cultural adaptation of instruments. A total of 127 Spanish-speaking patients with shoulder pain were included in the study and asked to complete the Spanish translated p-ASES form, the Patient-Reported Outcomes Measurement Information System (PROMIS) v1.2 Physical Function SF 20a in Spanish and a demographics questionnaire. Construct validity was tested using correlational analysis between the Spanish translation of the p-ASES to the Spanish translation of the PROMIS v1.2 Physical Function Short Form 20a. Reliability was measured using both test-retest reliability and internal consistency (Cronbach α) in a subgroup of 27 patients who completed both surveys at a separate time point. RESULTS: The p-ASES demonstrated desirable convergent validity with the validated Spanish version of the PROMIS v1.2 Physical Function Short Form 20a with a strong correlation (r = 0.82, P < .04) for Spanish speakers. The Spanish translation of the p-ASES proved to be a reliable tool with a high degree of internal consistency across question items (α = 0.90). The Spanish p-ASES also demonstrated excellent test-retest reliability with a strong correlation (r = 0.87, P < .001) between time 1 and time 2. CONCLUSION: The Spanish p-ASES is both a valid and reliable tool for assessing shoulder function in Spanish-speaking patients from diverse cultural backgrounds and it demonstrates psychometric properties equivalent to those of the English-language version.


Subject(s)
Elbow , Shoulder , Surgeons , Humans , Language , Psychometrics , Reproducibility of Results , Surveys and Questionnaires , United States
6.
Orthop J Sports Med ; 7(9): 2325967119867920, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31579680

ABSTRACT

BACKGROUND: When treated conservatively, unstable distal clavicle fractures demonstrate a high symptomatic nonunion rate. While a variety of surgical techniques have been described, many of these techniques are associated with high failure rates and hardware-related complications. The surgical technique used in this study has shown promising biomechanical results; however, long-term clinical results have not yet been described. PURPOSE: To assess the clinical and radiological outcomes of a surgical technique for fixing displaced distal clavicle fractures using a combination of cortical button fixation and coracoclavicular (CC) ligament reconstruction. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We conducted a retrospective review of 22 consecutive patients with displaced, unstable Neer type II or V distal clavicle fractures who underwent this surgical technique from 2012 to 2019. Primary outcome variables were radiographic union, patient satisfaction, and postoperative shoulder function. Preoperative and postoperative University of California, Los Angeles (UCLA), and American Shoulder and Elbow Surgeons (ASES) scores were compared. Secondary outcome variables included intraoperative complications, postoperative complications, time to radiographic union, and preoperative and postoperative CC distance. Quality of life was assessed using preoperative and postoperative 36-Item Short Form Health Survey (SF-36) scores. RESULTS: Nearly all (21/22) patients were available for a final review; 1 patient was lost to follow-up at 2 weeks. All 21 patients achieved radiographic union by 4 months (mean, 60.38 days; range, 41-84 days; 95% CI, 53.80-66.96 days). All patients were satisfied with the surgical procedure and their functional outcome. The mean UCLA score improved from 5.36 (95% CI, 4.14-6.60) preoperatively to 32.52 (95% CI, 30.56-34.48) postoperatively (mean difference, 27.14; P < .001). The mean ASES score improved from 16.23 (95% CI, 9.79-22.67) preoperatively to 88.11 (95% CI, 81.82-94.40) postoperatively (mean difference, 71.91; P < .001). Statistically significant improvements in SF-36 scores were seen in the physical functioning, role limitations due to physical health, pain, social functioning, and emotional well-being categories. There were 3 postoperative complications, including 1 patient with a minor complication secondary to hardware irritation, 1 patient with adhesive capsulitis, and 1 patient with wound dehiscence requiring wound closure. CONCLUSION: We describe a surgical technique for fixing displaced distal clavicle fractures using a combination of cortical button fixation and CC ligament reconstruction that resulted in a 100% union rate and excellent clinical outcomes with acceptable complications.

7.
Cureus ; 11(2): e4091, 2019 Feb 19.
Article in English | MEDLINE | ID: mdl-31032151

ABSTRACT

Objective To define the critical elements of common procedures in arthroscopic surgery. Methods A survey was administered to surgeons associated with the American Orthopaedic Society for Sports Medicine (AOSSM) to determine the critical elements for four common arthroscopic procedures: anterior cruciate ligament (ACL) reconstruction, knee arthroscopy with meniscal debridement or repair, rotator cuff repair (RCR), and capsulorrhaphy for anterior glenohumeral instability (Bankart repair). Respondents were asked which steps necessitated their direct supervision. The level of experience and practice demographics were also recorded. Results For all applicable procedures, patient positioning and closure were not considered critical steps. Establishing arthroscopic portals was critical for all procedures, except knee arthroscopy. Diagnostic arthroscopy was only critical in ACL reconstruction. Private practice surgeons considered every step of these common procedures to be critical elements. Less experienced surgeons were more likely to regard certain aspects of a procedure critical. Surgeons with >15 years of experience considered diagnostic arthroscopy critical to all procedures, whereas those with <15 years of experience did not. Unlike surgeons with a resident as first assist, surgeons with a physician assistant (PA) or nurse practitioner (NP) found every step of each procedure to be critical except closure and positioning. Conclusion Across all procedures, only patient positioning and closure were consistently regarded as non-critical elements. There were significant differences in responses according to experience and practice setting. Future research is necessary to determine the implications of these findings and guide the definition of the "critical portions" of surgery.

8.
J Shoulder Elbow Surg ; 28(5): 982-988, 2019 May.
Article in English | MEDLINE | ID: mdl-30713066

ABSTRACT

BACKGROUND: Unstable distal clavicular fractures treated surgically are associated with high failure rates and hardware-related complications. Newer techniques have shown promising early clinical results with fewer hardware complications; however, their biomechanical performance has not been assessed. This study biomechanically compared a distal-third locking plate with 3 newer techniques that incorporate coracoid fixation into the construct. METHODS: The study randomized 36 adult fresh frozen cadaveric shoulders to 4 groups: (1) distal-third locking plate (P); (2) distal-third locking plate with a coracoid button augmentation (P + CB); (3) coracoclavicular button (CB); and (4) coracoclavicular button with coracoclavicular ligament reconstruction using semitendinosus allograft (CB + CC). After fixation, each specimen was stressed in the coronal plane. Cyclic displacement, load at 10-mm displacement, and ultimate load to failure were measured. RESULTS: All 3 experimental groups biomechanically outperformed the locking plate. Mean load to failure was significantly higher in the CB (343 ± 76 N) and CB + CC (349 ± 94 N) groups compared with the P group (193 ± 52 N). There was also significantly less cyclic displacement in the CB (4.3 ± 1.9 mm) and CB + CC (4.4 ± 1.9 mm) groups compared with the P group (8.2 ± 2.9 mm). With respect to load at 10 mm of displacement, which essentially measures a clinical failure, the P + CB (235 ± 112 N), CB (253 ± 111 N), and CB+CC (238 ± 76 N) experimental groups significantly outperformed the P group (96 ± 29 N). CONCLUSIONS: CB and CB + CC techniques demonstrated more than 75% greater strength than the traditional locking plate alone. Coupled with greater overall construct strength and lower-profile hardware, these newer techniques may result in improved clinical outcome and fewer hardware-related complications.


Subject(s)
Bone Plates , Clavicle/injuries , Fracture Fixation, Internal/methods , Fractures, Bone/surgery , Acromioclavicular Joint/physiopathology , Adult , Aged , Aged, 80 and over , Biomechanical Phenomena , Cadaver , Clavicle/surgery , Female , Fracture Fixation, Internal/instrumentation , Fractures, Bone/physiopathology , Humans , Ligaments, Articular/surgery , Male , Middle Aged
9.
Arthrosc Tech ; 7(4): e411-e415, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29942734

ABSTRACT

Management of distal clavicle fractures remains controversial. Various treatment options have been described including open reduction and internal fixation with hook plate fixation, tension band wiring, screw fixation, and distal locking plates. Many of these techniques are associated with a high perioperative complication rate. We describe a surgical technique that allows indirect fixation of distal clavicle fractures and reconstruction of the CC ligaments without the use of prominent hardware.

10.
J Surg Orthop Adv ; 23(3): 155-61, 2014.
Article in English | MEDLINE | ID: mdl-25153814

ABSTRACT

To examine whether anchors used in arthroscopic Bankart repair increased the risk of subsequent fracture, six intact polyurethane scapulae and six with three 3.0-mm suture anchors placed along the anteroinferior glenoid were compared. An axial load of 1 mm/s was applied to the anteroinferior glenohumeral joint with a prosthetic humeral head. Outcome measures were force needed for initial fracture and catastrophic failure, percent of anterior glenoid bone loss, and fracture length. With the numbers available, no significant differences could be detected between groups in yield load or maximum load. The anchor group had a significantly larger percentage of bone loss (p < .01) and fracture length (p < .01) compared to the intact group. In this study, anchors did not decrease force needed to fracture but did lead to significantly larger fractures of the anterior glenoid during a simulated dislocation event. Further study using various anchors and techniques is warranted.


Subject(s)
Arthroscopy/adverse effects , Fractures, Bone/etiology , Glenoid Cavity/injuries , Shoulder Dislocation/surgery , Suture Anchors/adverse effects , Adolescent , Adult , Bone Resorption , Fractures, Bone/pathology , Fractures, Bone/surgery , Glenoid Cavity/pathology , Glenoid Cavity/surgery , Humans , Joint Instability/etiology , Joint Instability/surgery , Male , Models, Biological , Recurrence , Reoperation , Retrospective Studies , Shoulder Joint/surgery , Weight-Bearing , Young Adult
11.
Clin Orthop Relat Res ; 472(3): 1050-7, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24338040

ABSTRACT

Effective treatment of knee extensor mechanism disruptions requires prompt diagnosis and thoughtful decision-making with surgical and nonsurgical approaches. When surgery is chosen, excellent surgical technique can result in excellent outcomes. Complications and failures arise from missed or delayed diagnoses and from technical problems in the operating room. In particular, inappropriate surgical timing (especially late surgery), misplaced patellar drill holes, and failure to address concomitant injuries can result in complications seen when repairing a patellar or quadriceps tendon tear. We review the complications that can occur during treatment of these injuries (Table 1).


Subject(s)
Knee Injuries/surgery , Knee Joint/surgery , Orthopedic Procedures/adverse effects , Patellar Ligament/surgery , Quadriceps Muscle/surgery , Biomechanical Phenomena , Humans , Knee Injuries/diagnosis , Knee Injuries/physiopathology , Knee Joint/physiopathology , Patellar Ligament/injuries , Patellar Ligament/physiopathology , Quadriceps Muscle/injuries , Quadriceps Muscle/physiopathology , Risk Factors , Treatment Outcome
12.
J Shoulder Elbow Surg ; 21(9): 1177-83, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22047785

ABSTRACT

INTRODUCTION: The range of motion (ROM) in the wrist and elbow required for daily activities has been reported to be less than the normal anatomic ROM. This functional ROM has not been defined for the shoulder. Many shoulder outcome assessment tools use specific functional tasks of daily living to score functional results of treatment. This study quantified the total shoulder ROM required to perform the functional tasks of the American Shoulder and Elbow Surgeon (ASES), Simple Shoulder Test (SST), and University of Pennsylvania (U-Penn) Shoulder Score (PSS). MATERIALS AND METHODS: The FASTRAK electromagnetic tracking system (Colchester, VT, USA) was used to test 40 shoulders in 20 volunteers with no shoulder pathology found on physical examination. Three sensors were used: 1 each on the T3 spinous process, the scapular spine, and the arm over the distal humerus. Subjects performed each functional task of the ASES, SST, and PSS while flexion, extension, abduction, adduction, external rotation, and internal rotation were recorded. RESULTS: Average shoulder motions required to perform the 10 functional tasks were flexion, 121° ± 6.7°; extension, 46° ± 5.3°; abduction, 128° ± 7.9°; cross-body adduction, 116° ± 9.1°; external rotation with the arm 90° abducted, 59° ± 10°; and internal rotation with the arm at the side, 102° ± 7.7°. CONCLUSION: Although attaining full motion is a reasonable goal of all shoulder treatment, our results indicate that less ROM is required to perform the functional tasks used in common outcome tools.


Subject(s)
Activities of Daily Living , Range of Motion, Articular/physiology , Shoulder Joint/physiology , Adult , Female , Humans , Male , Reference Values
13.
J Surg Res ; 135(2): 242-9, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16926028

ABSTRACT

BACKGROUND: There is great interest in the field of transplantation to genetically modify grafts to decrease preservation injury or allograft rejection. Although adenoviral gene transfer has been effective in experimental liver transplantation, viral toxicity and safety concerns limit potential use in clinical trials. Therefore, the purpose of this study was to develop a model of nonviral gene transfer in the liver transplant setting, allowing for efficient transgene expression. MATERIALS AND METHODS: Orthotopic syngeneic rat liver transplantation was performed with 3 h cold ischemia using University of Wisconsin (UW) preservation. A hydrodynamic gene transfer technique was developed where plasmid DNA was delivered to the liver graft by ex vivo rapid infusion of DNA in UW via the IVC with other vessels clamped. Expression plasmids for the marker genes luciferase and secreted human alpha1-antitrypsin (alpha1-AT) were used. Hepatic injury was assessed by graft histology and liver transaminases. Transgene expression was determined by hepatic luciferase relative light units activity (RLU) and serum alpha1-AT protein levels. Variables examined included the effect of (a) volume injected on the intravenous pressure in the liver graft; (b) injury to the liver, as measured by hepatic enzymes and histopathology; (c) variable expression between lobes; (d) volume of UW that the plasmid is administered in; (e) amount of DNA plasmid; (f) type of the promoter used; (g) clamp time; as well as (h) the time course of the marker gene expression. RESULTS: Control rats underwent standard orthotopic syngeneic rat liver transplantation and had no detectable hepatic luciferase activity or serum human alpha1-AT. The optimal DNA plasmid dose was found to be 400 mug/liver graft, as there was no increase in the luciferase expression by increasing the dose. Furthermore, cytomegalovirus promoter yielded greater expression than Rous sarcoma virus. A high injection pressure gradient allowed for more efficient transgene expression, but produced greater liver injury shown by elevated transaminases and centrilobular necrosis. Lowering injection volume from 75 to 50% of graft weight decreased liver injury by 4.5-fold. Although higher UW injection volumes were associated with increased expression, volumes of only 50% led to luciferase expression up to 10,000,000 RLU/mg; this expression was homogeneous between the different liver lobes. Human alpha1-AT was detected in recipient blood as early as 6 h, peaked at 24 h, and remained high for 5 days. CONCLUSIONS: We have developed a nonviral gene transfer technique where hydrostatic pressure across the cold-preserved liver vascular bed allows for efficient plasmid DNA delivery. This simple strategy should prove useful to genetically modify liver grafts in the transplantation setting.


Subject(s)
Gene Transfer Techniques , Genetic Therapy/methods , Graft Rejection/therapy , Liver Transplantation/methods , Analysis of Variance , Animals , Graft Rejection/prevention & control , Histocytochemistry , Liver/metabolism , Luciferases , Male , Plasmids/genetics , Pressure , Rats , Rats, Inbred Lew , Transgenes/genetics , alpha 1-Antitrypsin
14.
Am J Physiol Gastrointest Liver Physiol ; 283(5): G1175-84, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12381532

ABSTRACT

The role of NF-kappaB, the rapid-response transcription factor for multiple genes, in cold ischemia-reperfusion (I/R) injury was examined after syngeneic transplantation of liver grafts. Lewis rat recipients were killed 1-48 h after reperfusion of three different liver grafts: 1) uninfected control, 2) infected ex vivo with control adenoviral vector (AdEGFP), and 3) infected ex vivo with AdIkappaB. In uninfected control livers, NF-kappaB was activated biphasically at 1-3 and 12 h after reperfusion with aspartate transaminase (AST) levels of 4,244 +/- 691 IU/l. The first peak of NF-kappaB activation associated with an increase of mRNA for TNF-alpha, IL-1beta, and IL-10. AdEGFP transfection resulted in similar outcomes. Interestingly, AdIkappaB-transfected liver grafts suffered more severe I/R injury (AST >9,000 IU/l). Transfected IkappaB was detected in transplanted livers as early as 6 h, and this correlated with the abrogation of the second, but not the first, peak of NF-kappaB activation at 12-48 h and increased apoptosis. Thus inhibition of the second wave of NF-kappaB activation in IkappaB-transfected livers resulted in an increase of liver injury, suggesting that NF-kappaB may have a dual role during liver I/R injury.


Subject(s)
Ischemia/pathology , Liver Circulation , Liver/pathology , NF-kappa B/metabolism , Reperfusion Injury/pathology , Adenoviridae/genetics , Animals , Apoptosis/physiology , Cryopreservation , Cytokines/genetics , DNA/metabolism , Gene Transfer Techniques , Genetic Vectors , I-kappa B Proteins/genetics , I-kappa B Proteins/metabolism , I-kappa B Proteins/pharmacology , Liver/drug effects , Male , NF-kappa B/genetics , RNA, Messenger/metabolism , Rats , Rats, Inbred Lew
15.
Hepatology ; 36(3): 573-81, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12198649

ABSTRACT

Organ graft preservation injury is a major problem complicating liver transplantation. The L-arginine/nitric oxide pathway has protective effects in several models of liver injury. The purpose of this study was to evaluate the role of the L-arginine/NO synthase (NOS) pathway on liver preservation injury and to characterize endogenous inducible NOS (iNOS) expression. Orthotopic liver transplantation was performed with 18-hour University of Wisconsin preservation solution in syngeneic rats. Recipient rats were either untreated or treated with L-arginine, D-arginine, nonspecific NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME), or iNOS selective inhibitor L-N(6)-(1-imino-ethyl)lysine (L-NIL) after revascularization. As early as 1 hour following reperfusion, circulating arginine levels decreased 10-fold and ornithine levels increased 4-fold. A corresponding increase in arginase I protein was detected in serum. To address the profound arginine deficiency, we supplemented recipients with arginine after transplantation. L-arginine (but not D-arginine) supplementation significantly reduced preservation injury 12 hours after reperfusion, suggesting that the protective effect of L-arginine was mediated through the generation of NO. iNOS protein expression peaked in the liver 6 to 12 hours following reperfusion. Blockade of the L-arginine/NO pathway with L-NAME significantly increased necrotic and apoptotic cell death in the transplanted graft. Addition of the iNOS selective inhibitor L-NIL mildly increased liver transaminase levels and also increased apoptosis in the liver graft. In conclusion, transplant recipients are profoundly arginine deficient postreperfusion due to arginase release. L-Arginine supplementation and NO synthesis decrease necrotic and apoptotic cell death and ameliorate liver transplant preservation injury.


Subject(s)
Apoptosis/physiology , Arginine/blood , Liver Transplantation , Liver/pathology , Nitric Oxide Synthase/antagonists & inhibitors , Animals , Apoptosis/drug effects , Arginase/metabolism , Arginine/deficiency , Arginine/pharmacology , Enzyme Inhibitors/pharmacology , Liver/enzymology , Male , NG-Nitroarginine Methyl Ester/pharmacology , Necrosis , Nitrates/blood , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Nitrites/blood , Rats , Rats, Inbred Lew , Up-Regulation/physiology
16.
Transplantation ; 74(1): 7-13, 2002 Jul 15.
Article in English | MEDLINE | ID: mdl-12134092

ABSTRACT

BACKGROUND: Endotoxin or lipopolysaccharide (LPS) initiates a cascade of complications of septic shock and multiple organ failure seen in Gram-negative bacterial infections. The first step of this pathway, which leads to activated nuclear factor (NF)-kappaB, activating protein (AP)-1, and other transcription factors, is the formation of the LPS receptor complex by LPS, LPS-binding protein (LBP), CD14, and toll-like receptor (TLR) 2 or 4. We examined whether the LPS signaling pathway is activated by hepatic ischemia/reperfusion injury in the transplant setting. METHODS: Orthotopic syngeneic rat liver transplantation was performed with 0 to 18 hr of cold preservation in University of Wisconsin solution. Animals were killed 1 to 48 hr after reperfusion. Northern blot analysis for CD14, LBP, and TLR2 mRNA, immunohistochemistry for LBP, liver enzyme analysis, and gel shift assay for NF-kappaB and AP-1 were performed. RESULTS: LPS levels were elevated early after reperfusion. Aspartate aminotransferase and alanine aminotransferase maximally increased 12 hr after transplantation. LBP mRNA and protein and CD14 mRNA were significantly up-regulated peaking at 6 to 12 hr after reperfusion. TLR2 mRNA was also increased. NF-kappaB activity showed a biphasic peak at 1 to 3 hr and 12 hr after reperfusion, whereas AP-1 activity showed a peak at 3 to 6 hr. The induction of CD14 mRNA correlated with the length of cold ischemia time. CONCLUSIONS: These data indicate that multiple components of the LPS signaling pathway are activated during ischemia/reperfusion injury after liver transplantation.


Subject(s)
Acute-Phase Proteins , Drosophila Proteins , Lipopolysaccharides/blood , Liver Transplantation , Reperfusion Injury/physiopathology , Signal Transduction/physiology , Animals , Carrier Proteins/analysis , Carrier Proteins/genetics , Cold Temperature , Gene Expression/physiology , Lipopolysaccharide Receptors/genetics , Liver/chemistry , Liver/physiology , Liver Function Tests , Male , Membrane Glycoproteins/genetics , NF-kappa B/metabolism , Postoperative Complications/physiopathology , Protein Binding/physiology , RNA, Messenger/analysis , Rats , Rats, Inbred Lew , Receptors, Cell Surface/genetics , Toll-Like Receptor 2 , Toll-Like Receptors , Transcription Factor AP-1/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...