Minimum 5-Year Clinical and Return-to-Sport Outcomes After Primary Arthroscopic Scapulothoracic Bursectomy and Partial Scapulectomy for Snapping Scapula Syndrome

BACKGROUND

Snapping scapula syndrome (SSS) is a rare condition that is oftentimes debilitating. For patients whose symptoms are resistant to nonoperative treatment, arthroscopic surgery may offer relief. Because of the rarity of SSS, reports of clinical outcomes after arthroscopic SSS surgery are primarily limited to small case series and short-term follow-up studies.

PURPOSE

To report minimum 5-year clinical and sport-specific outcomes after arthroscopic bursectomy and partial scapulectomy for SSS and to identify demographic and clinical factors at baseline associated with clinical outcomes at minimum 5-year follow-up.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients who underwent arthroscopic bursectomy and partial scapulectomy for SSS between October 2005 and February 2016 with a minimum of 5 years of postoperative follow-up were enrolled in this single-center study. Clinical outcome scores, including the 12-Item Short Form Health Survey (SF-12), American Shoulder and Elbow Surgeons (ASES) Shoulder Score, shortened version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, Single Assessment Numeric Evaluation (SANE), and visual analog scale (VAS) score for pain, were collected at a minimum 5-year follow-up. Additionally, it was determined which patients reached the minimal clinically important difference. Bivariate analysis was used to determine whether baseline demographic and clinical factors had any association with the outcome scores.

RESULTS

Of 81 patients eligible for inclusion in the study, follow-up was obtained for 66 patients (age 33.6 ± 13.3 years; 31 female). At a mean follow-up of 8.9 ± 2.5 years (range, 5.0-15.4 years), all of the outcome scores significantly improved compared with baseline. These included the ASES (from 56.7 ± 14.5 at baseline to 87.2 ± 13.9 at follow-up; P < .001), QuickDASH (from 38.7 ± 17.6 to 13.1 ± 14.6; P < .001), SANE (from 52.4 ± 21.2 to 82.7 ± 19.9; P < .001), SF-12 Physical Component Summary (from 39.7 ± 8.3 to 50.3 ± 8.2; P < .001), SF-12 Mental Component Summary (from 48.2 ± 11.7 to 52.0 ± 9.0; P = 0.014) and VAS pain (from 5.2 ± 2.1 to 1.4 ± 2.0; P < .001). The minimal clinically important difference in the ASES score was reached by 77.6% of the patients. Median postoperative satisfaction was 8 out of 10. It was found that 90.5% of the patients returned to sport, with 73.8% of the patients able to return to their preinjury level. At the time of final follow-up, 8 (12.1%) patients had undergone revision surgery for recurrent SSS symptoms. Older age at surgery (P = .044), lower preoperative SF-12 Mental Component Summary score (P = .008), lower preoperative ASES score (P = .019), and increased preoperative VAS pain score (P = .016) were significantly associated with not achieving a Patient Acceptable Symptom State on the ASES score.

CONCLUSION

Patients undergoing arthroscopic bursectomy and partial scapulectomy for SSS experienced clinically significant improvements in functional scores, pain, and quality of life, which were sustained at a minimum of 5 years and a mean follow-up of 8.9 years postoperatively. Higher patient age, inferior mental health status, increased shoulder pain, and lower ASES scores at baseline were significantly associated with worse postoperative outcomes.

Patient-reported outcomes of arthroscopic repair for partial or full-thickness upper third subscapularis tendon tears with open sub-pectoral biceps tenodesis: minimum 10-year outcomes

BACKGROUND

Although short-term results are promising, there are limited data for long-term results of arthroscopic subscapularis (SSC) repair. The purpose of this study is to report minimum 10-year outcomes of primary arthroscopic repair of isolated partial or full-thickness tears of the upper third of the SSC tendon.

METHODS

Patients who underwent arthroscopic repair of isolated upper third SSC tears, Lafosse type I (>50% of tendon thickness) or type II were included. Surgeries were performed by a single surgeon between November 2005 and August 2011. Patient-reported outcome measures were prospectively collected and retrospectively reviewed at minimum follow-up of 10 years. Patient-reported outcomes utilized included the American Shoulder and Elbow Surgeons score, Single Assessment Numeric Evaluation score (SANE), Quick Disabilities of the Arm, Shoulder and Hand score (QuickDASH), the Short Form 12 physical component summary, return to activity, and patient satisfaction. A subanalysis of patient age and outcomes was performed. Retears, revision surgeries, and surgical complications were recorded.

RESULTS

In total, 29 patients with isolated upper third SSC repairs were identified. After application of exclusion criteria, 14 patients were included in the final analysis. Follow-up could be obtained from 11 patients. The mean age at surgery was 52.7 years (range: 36-72) and the mean follow-up was 12 years (range 10-15 years). The American Shoulder and Elbow Surgeons score improved from 52.9 ± 21.8 preoperatively to 92.2 ± 13.7 postoperatively (P < .001). Regarding the SANE and QuickDASH scores, only postoperative data were available. Mean postoperative SANE, QuickDASH, and Short Form 12 physical component summary scores were 90.27 ± 10.5, 14.6 ± 15.5, and 49.2 ± 6.6, respectively. Median patient satisfaction was 10 (range 6-10). Patients reported improvements in sleep, activities of daily living, and sports. There was no correlation between patient age and clinical outcome (P > .05). No patients underwent revision surgery for a SSC retear.

CONCLUSION

Arthroscopic repair of upper third SSC tendon tears leads to improved clinical scores and high patient satisfaction at minimum 10-year follow-up. The procedure is durable, with no failures in the presented cohort.

Preoperative patient factors that predict achieving the minimal clinically important difference following arthroscopic treatment of snapping scapula syndrome

PURPOSE

The aim of this study was to define minimal clinically important difference (MCID) values for patient-reported outcomes (PROs) after arthroscopic treatment of snapping scapula syndrome (SSS) using a distribution-based method, and to identify demographic, clinical, and intraoperative factors significantly associated with the achievement of MCID.

METHODS

Patients who underwent arthroscopic treatment of SSS between October 2005 and September 2020 with a minimum of 2-year short-term postoperative follow-up were enrolled in this retrospective monocentric study. The MCID was calculated using a distribution-based approach for the following patient-reported outcomes (PROs): 12-Item Short Form Survey (SF-12), American Shoulder and Elbow Surgeons (ASES), Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH), Single Assessment Numeric Evaluation (SANE), and VAS pain "today" and "at worst." The association between achievement of the MCID and postoperative subjective satisfaction was investigated and factors associated with achievement of MCID were determined using bivariate analysis.

RESULTS

Of a total of 190 patients assessed for eligibility, 77 patients (38.1±14.3 years; 36 females) were included. Within the study population, statistically significant improvements in postoperative SF-12 PCS (p<.001) and MCS (p<0.034), ASES (p<.001), QuickDASH (p<.001), SANE (p<.001), and VAS pain (p<.001) were observed at minimum 2-year follow-up. The calculated MCID threshold values based on the study population were 5.0 for SF-12 PCS, 5.8 for SF-12 MCS, 11.3 for the ASES score, -10.5 for the QuickDASH score, 14.7 for SANE, 1.5 for the VAS pain, and 1.7 for the VAS pain at worst. Reaching the MCID was strongly associated with postoperative satisfaction (rated on a scale of 1-10). Across the PROs, younger age, favorable preoperative response to injection, partial scapuloplasty or scapulectomy, no prior surgery, as well as pain and function at baseline were significantly associated with attaining MCID.

CONCLUSIONS

Patients who underwent arthroscopic treatment for SSS experienced clinically significant improvements in functional scores, pain, and quality of life. This study demonstrated predictive roles for certain patient-specific factors and diagnostic variables for achieving MCID in PROs, which may help surgeons preoperatively assess preoperatively the probability of success and manage patient expectations.

Mid-Term Outcomes of Microfracture for the Treatment of Focal, Full-Thickness Cartilage Defects Isolated to the Humeral Head

BACKGROUND

While microfracture has been shown to be an effective treatment for chondral lesions in the knee, evidence to support its use for chondral defects in the shoulder is limited to short-term outcomes studies. The purpose of this study is to determine if microfracture provides pain relief and improved shoulder function in patients with isolated focal chondral defects of the humeral head at a minimum 5-year follow-up.

METHODS

Patients who underwent microfracture procedure for isolated focal chondral defects of the humeral head with a minimum follow-up of 5 years between 02/2006 and 08/2016 were included. At minimum 5-year follow-up, pre- and postoperative Patient Reported Outcome (PRO) measures were collected, including the American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH), Short Form-12 (SF-12) Physical Component Summary (PCS), Visual Analog Scale (VAS) for pain, and patient satisfaction level (1=unsatisfied, 10=very satisfied). Demographic, injury, and surgical data were retrospectively reviewed. Surgical failure was defined as revision surgery for humeral chondral defects or conversion to arthroplasty. Kaplan-Maier analysis was performed to determine survivorship at 5 years.

RESULTS

A total of 17 patients met inclusion/exclusion criteria. There were 15 men and 2 women with an average age of 51 years (range 36-69) and an average follow-up of 9.4 years (range 5.0 - 15.8). The median ASES score improved from 62 (range: 22-88) preoperatively to 90 (range: 50-100) postoperatively (p=.011). Median satisfaction was 8 out of 10 (range: 2-10). There was no correlation between patient age or defect size and PROs. Postoperatively, patients reported significant improvements in recreational and sporting activity as well as the ability to sleep on the affected shoulder (p= <0.05). Three patients failed and required revision surgery. The Kaplan-Meier analysis determined an overall survivorship rate of 80% at 5 years.

CONCLUSION

The presented study illustrates significant improvements for PROs, improved ability to perform recreational and sporting activities, and a survival rate of 80% at a mean of 9.4 years after microfracture for focal chondral humeral head defects.

Improved Functional Outcomes of Combined Hip Arthroscopy and Periacetabular Osteotomy at Minimum 2-Year Follow-Up

PURPOSE

To evaluate patient-reported outcomes (PROs) and survivorship at minimum 2-year follow-up after combined hip arthroscopy and periacetabular osteotomy (PAO) performed in the setting of a single anesthetic event.

METHODS

Patients who underwent combined hip arthroscopy (M.J.P.) and PAO (J.M.M.) between January 2017 and June 2020 were identified. Preoperative and minimum 2-year postoperative PROs including Hip Outcome Score-Activities of Daily Living (HOS-ADL), HOS-Sport, modified Harris Hip Score (mHHS), Western Ontario and McMaster Universities Osteoarthritis Index, 12-Item Short Form Survey Mental Component Scores (SF-12 MCS), and 12-Item Short Form Survey Physical Component Score were collected and compared in addition to revision rate, conversion to total hip arthroplasty (THA), and patient satisfaction.

RESULTS

Twenty-four of 29 patients (83%) eligible for the study were available for 2-year minimum follow-up with a median follow-up time of 2.5 years (range, 2.0-5.0). There were 19 females and 5 males with mean age of 31 ± 12 years. Mean preoperative lateral center edge angle was 20° ± 5° and alpha angle was 71° ± 11°. One patient underwent reoperation for removal of a symptomatic iliac crest screw at 11.7 months after operation. Two patients, a 33-year-old woman and a 37-year-old man, were converted to THA at 2.6 and 1.3 years, respectively, following the combined procedure. Both patients had a Tönnis grade of 1 on radiographs, as well as bipolar Outerbridge grade III/IV defects requiring microfracture of the acetabulum. For patients who did not convert to THA (n = 22), there was significant improvement from before to after surgery for all scores (P < .05) except SF-12 MCS. The minimal clinically significant difference and patient-acceptable symptom state rates for HOS-ADL, HOS-Sport, and mHHS were 72%, 82%, 86%, and 95%, 91%, and 95%, respectively. Median patient satisfaction was 10 (range, 4 to 10).

CONCLUSIONS

Single-stage combined hip arthroscopy with periacetabular osteotomy for patients with symptomatic hip dysplasia results in improvement in PROs and arthroplasty free survivorship of 92% at median 2.5 year follow-up.

LEVEL OF EVIDENCE

Level IV, case series.

Does glenoid version and its correction affect outcomes in anatomic shoulder arthroplasty? A systematic review

BACKGROUND

Correction of glenoid retroversion is commonly performed in anatomic total shoulder arthroplasty (TSA) to increase component contact area and decrease eccentric loading of the glenoid component. Despite demonstrated biomechanical advantages, limited information exists on the clinical benefit of correcting glenoid retroversion. The purpose of this systematic review is to critically evaluate the existing literature on the effect of preoperative and postoperative glenoid retroversion on clinical functional and radiologic outcomes in patients who underwent anatomic TSA.

METHODS

A systematic literature review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses using PubMed, Embase, and Cochrane Library evaluating the impact of glenoid retroversion on clinical and radiologic outcomes of TSA. English-language studies of level I through IV evidence were included. Blinded reviewers conducted multiple screens and methodological quality was appraised using the Modified Coleman Methodology Score.

RESULTS

Sixteen studies, including 3 level III and 13 level IV studies (1211 shoulders), satisfied all inclusion criteria. To address glenoid retroversion, 9 studies used corrective reaming techniques, and 4 studies used posteriorly augmented glenoids. Two studies used noncorrective reaming techniques. Mean preoperative retroversion ranged from 12.7° to 24° across studies. Eleven studies analyzed the effect of glenoid retroversion on clinical outcomes, including patient-reported outcome scores (PROs), range of motion (ROM), or clinical failure or revision rates. Most studies (8 of 11) did not report any significant association of pre- or postoperative glenoid retroversion on any clinical outcome. Of the 3 studies that reported significant effects, 1 study reported a negative association between preoperative glenoid retroversion and PROs, 1 study reported inferior postoperative abduction in patients with postoperative glenoid retroversion greater than 15°, and 1 study found an increased clinical failure rate in patients with higher postoperative retroversion. Ten studies reported radiographic results (medial calcar resorption, Central Peg Lucency [CPL] grade, Lazarus lucency grade) at follow-up. Only 1 study reported a significant effect of pre- and postoperative retroversion greater than 15° on CPL grade.

CONCLUSION

There is currently insufficient evidence that pre- or postoperative glenoid version influences postoperative outcomes independent of other morphologic factors such as joint line medialization. Given that noncorrective reaming demonstrated favorable postoperative outcomes, and postoperative glenoid version was not significantly and consistently found to impact outcomes, there is inconclusive evidence that correcting glenoid retroversion is routinely required.

Therapeutic potential of senolytic agent quercetin in osteoarthritis: A systematic review and meta-analysis of preclinical studies

BACKGROUND

Quercetin, a natural flavonoid, has shown promise as a senolytic agent for various degenerative diseases. Recently, its protective effect against osteoarthritis (OA), a representative age-related disease of the musculoskeletal system, has attracted much attention. The aim of this study is to summarize and analyze the current literature on the effects of quercetin on OA cartilage in in vivo preclinical studies.

METHODS

The Medline (via/using PubMed), Embase, and Web of Science databases were searched up to March 10th, 2023. Risk of bias and the qualitative assessment including mechanisms of all eligible studies and a meta-analysis of cartilage histological scores among the applicable studies was performed.

RESULTS

A total of 12 in vivo animal studies were included in this systematic review. A random-effects meta-analysis was performed on six studies using the Osteoarthritis Research Society International (OARSI) scoring system, revealing that quercetin significantly improved OA cartilage OARSI scores (SMD, -6.30 [95% CI, -9.59 to -3.01]; P = 0.0002; heterogeneity: I2 = 86%). The remaining six studies all supported quercetin's protective effects against OA during disease and aging.

CONCLUSIONS

Quercetin has shown beneficial effects on cartilage during OA across animal species. Future double-blind randomized controlled clinical trials are needed to verify the efficacy of quercetin in the treatment of OA in humans.

Sternoclavicular Joint Reconstruction With Gracilis Tendon Autograft

Clinical instability of the sternoclavicular (SC) joint is a challenging problem. Recurrent subluxation and pain can lead to significant functional limitations. Although many patients respond positively to conservative treatment, chronic dislocations often require operative intervention. The complex anatomy of the diarthrodial SC joint and the existence of concomitant SC joint degenerative changes compounded with close-by neurovascular structures present a surgical challenge. The purpose of this Technical Note is to describe a technique for the open management of symptomatic sternoclavicular joint instability using a figure-of-8 reconstruction with a gracilis autograft. The present authors believe this technique provides a technically safe and reproducible method for reconstructing the SC joint without compromising biomechanical strength.

Arthroscopic Labral Repair and Pancapsular Shift With Knotless All-Suture Anchors in the Setting of Multidirectional Instability of the Shoulder

In the management of multidirectional type of shoulder instability (MDI), arthroscopic surgical stabilization is a preferred treatment option after failed conservative therapy regimens because of the ability to easily access all aspects of the capsule with one surgical procedure. As arthroscopic techniques have evolved, factors critical to postoperative success have been elucidated. Currently, optimal arthroscopic treatment of MDI involves circumferentially restoring labral integrity, a tailored, patient-specific surgical reduction of capsular volume, and adequately managing potential lesions of the biceps anchor. The purpose of this article and accompanying video is to present our technique for arthroscopic circumferential labral repair and pancapsular shift using knotless all-suture anchors in the setting of MDI with a concurrent type II SLAP lesion.

Minimum 5-Year Clinical Outcomes of Arthroscopically Repaired Massive Rotator Cuff Tears: Effect of Age on Clinical Outcomes

BACKGROUND

Massive rotator cuff tears (MRCTs) can be challenging to treat, and the efficacy of repair of MRCTs in older patients has been debated.

PURPOSE

To report minimum 5-year outcomes after primary arthroscopic rotator cuff repair of MRCT and determine whether age affects outcomes.

STUDY DESIGN

Case series; Level of evidence 4.

METHODS

The study included consecutive patients with MRCTs who were treated with arthroscopic rotator cuff repair by a single surgeon between February 2006 and October 2016. MRCTs were defined as ≥2 affected tendons with tendon retraction to the glenoid rim and/or a minimum exposed greater tuberosity of ≥67. Patient-reported outcome (PRO) data collected preoperatively and at a minimum of 5 years included the American Shoulder and Elbow Surgeons (ASES) score; Single Assessment Numeric Evaluation (SANE) score; the shortened version of the Disabilities of the Arm, Shoulder and Hand score (QuickDASH); the 12-Item Short Form Health Survey (SF-12) Physical Component Summary (PCS); and patient satisfaction. Surgical failure was defined as subsequent revision rotator cuff surgery or conversion to reverse total shoulder arthroplasty. Regression analysis was performed to determine whether age had an effect on clinical outcomes.

RESULTS

A total of 53 shoulders in 51 patients (mean age, 59.7 years; range, 39.6-73.8 years; 34 male, 19 female) met inclusion criteria with a mean follow-up of 8.1 years (range, 5.0-12.1 years). Three shoulders (5.7%) failed at 2.4, 6.0, and 7.1 years. Minimum 5-year follow-up was obtained in 45 of the remaining 50 shoulders (90%). Mean PROs improved as follows: ASES from 58.8 to 96.9 (P < .001), SANE from 60.5 to 88.5 (P < .001), QuickDASH from 34.2 to 6.8 (P < .001), and SF-12 PCS from 41.1 to 52.2 (P < .001). Patient satisfaction was a median of 10 (on a scale of 1-10). Age was not associated with any PRO measures postoperatively (P > .05).

CONCLUSION

This study demonstrated significantly improved clinical scores, decreased pain, and increased return to activity for patients with MRCT at midterm follow-up (mean, 8.1 years; range, 5.0-12.1 years). In this patient cohort, no association was found between age and clinical outcomes.

Minimum 10-Year Outcomes After Arthroscopic Repair of Partial-Thickness Supraspinatus Rotator Cuff Tears

BACKGROUND

The prevalence of partial-thickness rotator cuff tears (PTRCTs) has been reported to be 13% to 40% within the adult population, accounting for 70% of all rotator cuff tears. Approximately 29% of PTRCTs will progress to full-thickness tears if left untreated. The long-term clinical course after arthroscopic repair of PTRCTs is not well known.

PURPOSE

To investigate minimum 10-year patient-reported outcomes (PROs) after arthroscopic rotator cuff repair (RCR) of the supraspinatus tendon and to report reoperation and complication rates.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients were included who underwent arthroscopic RCR of a PTRCT performed by a single surgeon between October 2005 and October 2011. Arthroscopic RCR was performed with a transtendon repair of partial, articular-sided supraspinatus tendon avulsions, bursal-sided repair, or conversion into a full-thickness tear and repair. PRO data were collected preoperatively and at a minimum 10 years postoperatively. PRO measures included the American Shoulder and Elbow Surgeons score, Single Assessment Numeric Evaluation score, the shortened version of Disabilities of the Arm, Shoulder and Hand score (QuickDASH), the 12-Item Short Form Health Survey Physical Component Summary, and patient satisfaction. Subanalyses were performed to determine if tear location or age was associated with outcomes. Retears, revision surgery, and surgical complications were recorded.

RESULTS

In total, 33 patients (21 men, 12 women) at a mean age of 50 years (range, 23-68) met criteria for inclusion. Follow-up was obtained in 28 (87.5%) of the 32 eligible patients ≥10 years out from surgery (mean, 12 years; range, 10-15 years). Of the 33 PTCRTs, 21 were articular sided and 12 were bursal sided. Of the 33 patients, 26 underwent concomitant biceps tenodesis. At follow-up, the mean PROs were significantly improved when compared with preoperative levels: American Shoulder and Elbow Surgeons score from 67.3 to 93.7 (P < .001), Single Assessment Numeric Evaluation from 70.9 to 91.2 (P = .004), QuickDASH from 22.3 to 6.6 (P < .004), and 12-Item Short Form Health Survey Physical Component Summary from 44.8 to 54.2 (P < .001). Median postoperative satisfaction was 10 (range, 5-10). No patient underwent revision surgery.

CONCLUSION

Arthroscopic repair of PTRCTs results in excellent clinical outcomes and high patient satisfaction at minimum 10-year follow-up. Furthermore, the procedure is highly durable, with a clinical survivorship rate of 100% at 10 years.

The effects of losartan or angiotensin II receptor antagonists on cartilage: a systematic review

OBJECTIVE

The aim of this study is to analyze the latest evidence on the effects of losartan or Ang II receptor antagonists on cartilage repair, with a focus on their clinical relevance.

DESIGN

The PubMed, Embase, and Cochrane Library databases were searched up to November 12th 2021 to evaluate the effects of losartan or Ang II receptor antagonists on cartilage repair in in vitro studies and in vivo animal studies. Study design, sample characteristics, treatment type, duration, and outcomes were analyzed. The risk of bias and the quality of the eligible studies were assessed using the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) risk of bias assessment tool and Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies (CAMARADES).

RESULTS

A total of 12 studies were included in this systematic review. Of the 12 eligible studies, two studies were in vitro human studies, three studies were in vitro animal studies, one study was an in vitro human and animal study, and six studies were in vivo animal studies. The risk bias and quality assessments were predominantly classified as moderate. Since meta-analysis was difficult due to differences in treatment type, dosage, route of administration, and method of outcome assessment among the eligible studies, qualitative evaluation was conducted for each study.

CONCLUSIONS

Both in vitro and in vivo studies provide evidence to demonstrate beneficial effects of Ang II receptor antagonists on osteoarthritis and cartilage defect models across animal species.

Treatment options for massive irreparable rotator cuff tears: a review of arthroscopic surgical options

While functional reconstruction of massive irreparable rotator cuff tears remains a challenge, current techniques aimed at recentering and preventing superior migration of the humeral head allow for clinical and biomechanical improvements in shoulder pain and function. Recentering of the glenohumeral joint reduces the moment arm and helps the deltoid to recruit more fibers, which compensates for insufficient rotator cuff function and reduces joint pressure. In the past, the concept of a superior capsular reconstruction with a patch secured by suture anchors has been used. However, several innovative arthroscopic treatment options have also been developed. The purpose of this article is to present an overview of new strategies and surgical techniques and if existing present initial clinical results. Techniques that will be covered include rerouting the long head of the biceps tendon, utilization of the biceps tendon as an autograft to reconstruct the superior capsule, utilization of a semitendinosus tendon allograft to reconstruct the superior capsule, superior capsular reconstruction with dermal allografts, and subacromial spacers.

Superior clinical results for early arthroscopic treatment of grade IIIb and V acromioclavicular joint instability compared to delayed operative treatment

BACKGROUND

Arthroscopy-assisted cortical fixation devices have been increasingly used in the operative management of both acute and chronic cases of acromioclavicular joint instability (ACJI). It has been hypothesized that delayed surgical management leads to inferior clinical and radiologic outcomes compared to acute treatment. The purpose of this study is to compare clinical and radiologic outcomes, scapula dyskinesia, and failure or revision rates of arthroscopically treated acute and chronic ACJI.

METHODS

This retrospective study of prospectively collected data included all surgically treated patients with grade IIIb and V chronic ACJI between 2013 and 2017, matched 1:1 to a group of acute grade IIIb and V ACJI patients treated during the same time period. Chronic ACJI was defined as delayed surgical treatment >21 days after injury. Chronic cases received an additional hamstring autograft next to the suture pulley systems. Follow-up was obtained at an average of 3.2 years (range: 1.4-6.2). Clinical outcome scores included the Constant-Murley Score (CMS), Taft Score (TF), Nottingham Clavicle Score (NCS), ACJI Score, Sick Scapula Score (SSS), Subjective Shoulder Value (SSV), Subjective Shoulder Test (SST), American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score, and the visual analog scale pain score. Radiologic follow-up was obtained pre- and postoperatively and at final follow-up. The 2-year results were compared to the results of a 1:1 matched-pair group comprising patients who were treated with an acute ACJI during the same period.

RESULTS

Thirty-three (80.5%) of 41 chronic ACJI cases were available for follow-up and were compared with 33 matched-pair cases of acute ACJI (of 41). The clinical scores were significantly better in the acute cohort for the CMS (92 ± 8 vs. 88 ± 8, P = .030), ASES (91 ± 13 vs. 85 ± 13, P = .002), SSS (1.4 ± 1.6 vs. 3.4 ± 2.5, P = .0004), NCS (86 ± 13 vs. 81 ± 13, P = .049), TF (9.9 ± 1.9 vs. 9.0 ± 2.1, P = .030), and ACJI (83 ± 13 vs. 75 ± 1, P = .003). In contrast to the chronic cohort, the acute cohort illustrated a significant loss of reduction at follow-up (P = .020).

CONCLUSION

Based on the results of this study, early arthroscopy-assisted operative treatment of grade IIIb and V ACJIs seems superior to delayed surgical intervention of grade IIIb and V ACJIs. Furthermore, an additional autograft loop leads to less loss of reduction compared with suture pulley/suspensory loop fixation standalones.

Arthroscopic Core Decompression for Avascular Necrosis of the Femoral Head Using Multiple Small-Diameter Tunnels

Avascular necrosis of the femoral head (AVNFH) is a debilitating disease that requires early intervention to prevent subchondral collapse and irreversible damage leading to premature hip replacement. Patients presenting with AVNFH can have concomitant intra-articular pathology, including femoroacetabular impingement (FAI), that contributes to their hip pain and dysfunction. It is important to restore the native hip anatomy in addition to providing revascularization of necrotic areas to reduce pain, improve function, and maximize efforts to preserve the joint. The purpose of this Technical Note is to describe our preferred arthroscopic approach to core decompression through the femoral neck in combination with femoral osteoplasty to address AVNFH and FAI in a single-staged and minimally invasive procedure.

A single meal has the potential to alter brain oxylipin content

Our objective was to determine whether consumption of a single meal has the potential to alter brain oxylipin content. We examined the cerebrum of mice fed a single high-fat/high-sucrose Western meal or a low-fat/low-sucrose control meal, as well as fasted mice. We found no changes in fatty acid composition of cerebrum across the groups. The cerebral oxylipin profile of mice fed a Western meal is distinct from the profile of mice fed a low-fat/low-sucrose meal. Cerebral gene expression of cyclooxygenase 1, cyclooxygenase 2, and epoxide hydrolase 1 were elevated in Western meal-fed mice compared to low-fat/low-sucrose meal-fed mice. Mice that consumed either meal had lower gene expression of cytochrome P450, family 2, subfamily j, polypeptide 12 than fasted mice. Our data in this hypothesis-generating study indicates that the composition of a single meal has the potential to alter brain oxylipins and the gene expression of the enzymes responsible for their production.

Raman spectroscopic analysis of biochemical changes in individual triglyceride-rich lipoproteins in the pre- and postprandial state

Individual triglyceride-rich lipoprotein (TGRL) particles derived from human volunteers are nondestructively analyzed by laser tweezers Raman microspectroscopy, and information on their composition and distribution is obtained. The Raman signature of single optically trapped very low-density lipoproteins (VLDL), a subclass of TGRL, which play an important role in cardiovascular disease, exhibits distinct peaks associated with molecular vibrations of fatty acids, proteins, lipids, and structural rearrangements of lipids. Our analysis of pre- and postprandial VLDL exhibits the signature of biochemical changes in individual lipoprotein particles following the consumption of meals. Interaction of VLDL with endothelium leads to the breakdown of complex triacylglycerols and the formation of a highly ordered core of free saturated fatty acids in the particle. A particle distribution analysis reveals trends in the degree to which this process has occurred in particles at different times during the postprandial period. Differences in particle distributions based on the different ratios of polyunsaturated to saturated fats in the consumed meals are also easily discerned. Individual lipoprotein particles hydrolyzed in vitro through addition of lipoprotein lipase (LpL) exhibit strikingly similar changes in their Raman spectra. These results demonstrate the feasibility of monitoring the dynamics of lipid metabolism of individual TGRL particles as they interact with LpL in the endothelial cell wall using Raman spectroscopy.

Multinutrient supplement containing ephedra and caffeine causes weight loss and improves metabolic risk factors in obese women: a randomized controlled trial

OBJECTIVE

To determine the safety and efficacy of a dietary supplement with a low dose of ephedra and caffeine in overweight/obese premenopausal female subjects.

DESIGN

A 9-month, double-blind, randomized control study compared the efficacy and safety of a dietary supplement with ephedra and caffeine to a control supplement.

SUBJECTS

Sixty-one healthy, premenopausal women with body mass index (BMI) from 27 to 39 kg/m2 were randomly assigned and received a dietary supplement (40 mg/day ephedra alkaloids, 100 mg/day caffeine, high potency mixture of vitamins, minerals, omega-3 fatty acids) or a control supplement for 9 months.

MEASUREMENTS

EFFICACY

changes in body weight, body composition, lipids, insulin, leptin, adiponectin, ghrelin, and self-reports of physical activity, diet and quality of life indices.

SAFETY

blood pressure, heart rate, electrocardiograms, urinalysis, blood histology, serum chemistry measures and self-reported symptoms.

RESULTS

Forty-one women completed the study. The treatment group lost significantly more body weight (-7.18 kg) and body fat (-5.33 kg) than the control group (-2.25 and -0.99 kg, respectively), and showed significant declines in heart rate, serum cholesterol, triglycerides, cholesterol to high-density lipoprotein ratio, glucose, fasting insulin, and leptin. Blood pressure, electrocardiograms, other clinical chemistry measures, blood histology, urinalysis, and self-reported physical activity were similar in the groups. Minor symptoms included dry mouth, insomnia, nervousness and palpitations. The treatment group reported more energy and decreased appetite compared to controls and scored higher on a quality of life domain assessing vitality.

CONCLUSION

A dietary supplement containing a low potency ephedra/caffeine mixture appeared safe and effective in causing loss of weight and body fat, and improving several metabolic parameters, including insulin sensitivity and lipid profiles when tested under physician supervision. Such supplements could be a useful tool to assist with weight loss.

Exponential processes in human auditory excitation and adaptation

Peripheral auditory adaptation has been studied extensively in animal models, and multiple exponential components have been identified. This study explores the feasibility of estimating these component processes for human listeners with a peripheral model of adaptation. The processes were estimated from off-frequency masked detection data that probed temporal masking responses to a gated narrowband masker. The resulting response patterns reflected step-like onset and offset features with characteristically little evidence of confounding backward and forward masking. The model was implemented with linear combinations of exponential functions to represent the unadapted excitation response to gating the masker on and then off and the opposing effects of adaptation in each instance. The onset and offset of the temporal masking response were assumed to be approximately inverse operations and were modeled independently in this scheme. The unadapted excitation response at masker onset and the reversed excitation response at masker offset were each represented in the model by a single exponential function. The adaptation processes were modeled by three independent exponential functions, which were reversed at masker offset. Each adaptation component was subtractive and partially negated the unadapted excitation response to the dynamic masker. This scheme allowed for quantification of the response amplitude, action latency, and time constant for the unadapted excitation component and for each adaptation component. The results reveal that (1) the amplitudes of the unadapted excitation and reversed excitation components grow nonlinearly with masker level and mirror the 'compressive' input-output velocity response of the basilar membrane; (2) the time constants for the unadapted excitation and reversed excitation components are related inversely to masker intensity, which is compatible with neural synchrony increasing at masker onset (or offset) with increasing masker strength; (3) the composite strength of adaptation levels off at high masker levels; this 'saturation' response is consistent with a diminished contribution from peripheral neural adaptation processes at high sound levels; and (4) the response dynamics for two of the adaptation components correspond generally to those for the 'very rapid'/'rapid' processes and 'short-term' processes described in animal studies of peripheral neural adaptation. The action latency of a third adaptation component suggests the role of a second-order peripheral or central process. This modeling exercise (1) indicates that multiple adaptation processes, whatever their origins, contribute substantively to the form of the temporal masking response and (2) supports a sum-of-exponentials scheme for estimating properties of the component processes.

Chronic estradiol treatment attenuates stiffening, glycoxidation, and permeability in rat carotid arteries

Aging-related changes in vascular stiffening and permeability are associated with cardiovascular disease. We examined the interaction of estradiol on the aging process in vascular tissue from rats by assessing the changes in endothelial layer permeability, arterial compliance, and glycoxidative damage levels. We isolated carotid arteries from ovariectomized (OVX) rats that underwent 1 yr of estrogen treatment with subcutaneous pellets and a subsequent 1 mo of cessation of treatment. Endothelial layer permeability and arterial compliance were determined using quantitative fluorescence microscopy. Endothelial layer permeability was reduced with estradiol treatment (estrogen groups, 2.58 +/- 0.21 ng dextran x min(-1) x cm(-2) vs. nonestrogen groups, 4.01 +/- 0.30 ng dextran x min(-1) x cm(-2); P < 0.05). Additionally, arteries from animals treated with estradiol had an increased compliance index (estrogen groups, 82.9 +/- 3.8 mm2. Torr vs. nonestrogen groups, 69.3 +/- 3.2 mm2. Torr; P < 0.05). Estradiol treatment also reduced levels of pentosidine, which is a specific marker of glycoxidative damage (estrogen groups, 0.11 +/- 0.03 pmol pentosidine/nmol collagen vs. nonestrogen groups, 0.20 +/- 0.03 pmol pentosidine/nmol collagen; P < 0.05). These results indicate that estradiol has multiple chronic vasculoprotective effects on the artery wall to maintain normal vascular wall function.

Early postnatal dexamethasone diminishes transforming growth factor alpha localization within the ileal muscularis propria of newborn mice and extremely low-birth-weight infants

Focal small bowel perforation (FSBP) occurs most commonly in the ileum of extremely low-birth-weight (ELBW) infants. Early postnatal dexamethasone (EPD) administration results in an increased risk for FSBP in this patient population, but the mechanism by which this occurs is unknown. Infants with FSBP have healthy mucosa but thinned smooth muscle, suggesting a mechanism involving the muscularis propria for these perforations. One explanation for these findings would be that dexamethasone alters the tissue availability of pertinent growth factors to the smooth muscle. To explore this possibility, we administered dexamethasone or saline by intraperitoneal injection to newborn mice for 3 days (dosed at 1 microg/g of body weight/day) to simulate EPD protocols. The animals were sacrificed after 72 h of treatment and their ileums harvested and prepared for microscopy. Immunolocalization was performed for three related growth factors (epidermal growth factor [EGF], heparin-binding EGF [h-EGF], and transforming growth factor alpha [TGF-alpha]) and their common receptor. We found TGF-alpha to be abundant and discretely localized in the muscularis propria in control animals but to be diminished in dexamethasone-treated animals. EGF-receptor immunostaining was also decreased with dexamethasone but there was minimal to no detection of EGF or h-EGF in either treatment condition. Surgical and autopsy specimens of the ileum were obtained from seven ELBW infants who either received EPD or not. These tissues were used for immunolocalization of the same growth factors and similar distributions for TGF-alpha were observed in several of these cases. These findings are consistent with an autocrine role for TGF-alpha in ileal smooth muscle proliferation and suggest a mechanism by which EPD might mediate smooth muscle thinning.

Predictors of plasma triglyceride elevation in patients participating in a coronary atherosclerosis treatment program

PURPOSE

Low-fat, high-carbohydrate diets have been used successfully to prevent and treat coronary heart disease, although these diets have been shown to cause elevations in fasting plasma triglyceride concentrations. The present study investigated metabolic factors (glucose, insulin, body weight) associated with changes in plasma triglyceride concentrations in patients participating in a comprehensive, multidisciplinary program, which included the use of a very low-fat diet designed to regress atherosclerotic cardiovascular disease.

METHODS

Thirty-six patients were entered into the study and placed on a 10% fat diet. Body mass index and fasting plasma insulin, glucose, lipids, and apolipoproteins were assessed at entrance into and after 3 months of participation in the program. Statistical analysis (discriminant function analysis) was used to identify factors that predicted elevations in plasma triglyceride that occurred during therapy.

RESULTS

For the entire group, significant reductions in body weight (-2.4%), fasting glucose (-6%), total cholesterol (-8%), and low-density lipoprotein cholesterol (-11%) were observed, while insulin and triglycerides showed no significant changes. Twenty-one of the patients experienced an increase in fasting triglyceride concentration of 10% or greater.

CONCLUSIONS

Three variables (baseline body mass index and fasting triglyceride and insulin concentrations) accurately classified 90% of those who would experience a > or = 10% elevation in triglycerides (P = 0.0002) and 67% of those who experienced no change. The present analysis provides a practical algorithm for clinicians to predict which patients will experience significant elevations in plasma triglyceride concentration when undergoing risk factor reduction that includes the consumption of a very low-fat, high-carbohydrate diet.

Depressive symptoms and risks of coronary heart disease and mortality in elderly Americans. Cardiovascular Health Study Collaborative Research Group

BACKGROUND

Several epidemiological studies have associated depressive symptoms with cardiovascular disease. We investigated whether depressive symptoms constituted a risk for coronary heart disease (CHD) and total mortality among an apparently healthy elderly cohort.

METHODS AND RESULTS

In a prospective cohort of 5888 elderly Americans (>/=65 years) who were enrolled in the Cardiovascular Health Study, 4493 participants who were free of cardiovascular disease at baseline provided annual information on their depressive status, which was assessed using the Depression Scale of the Center for Epidemiological Studies. These 4493 subjects were followed for 6 years for the development of CHD and mortality. The cumulative mean depression score was assessed for each participant up to the time of event (maximum 6-year follow-up). Using time-dependent, proportional-hazards models, the unadjusted hazard ratio associated with every 5-unit increase in mean depression score for the development of CHD was 1.15 (P:=0.006); the ratio for all-cause mortality was 1.29 (P:<0.0001). In multivariate analyses adjusted for age, race, sex, education, diabetes, hypertension, cigarette smoking, total cholesterol, triglyceride level, congestive heart failure, and physical inactivity, the hazard ratio for CHD was 1.15 (P:=0.006) and that for all-cause mortality was 1.16 (P:=0.006). Among participants with the highest cumulative mean depression scores, the risk of CHD increased by 40% and risk of death by 60% compared with those who had the lowest mean scores.

CONCLUSIONS

Among elderly Americans, depressive symptoms constitute an independent risk factor for the development of CHD and total mortality.

Direct visualization of lipid deposition and reverse lipid transport in a perfused artery : roles of VLDL and HDL

The major goal of this study was to determine the interactions of VLDL surface and core lipids with the artery wall. We first demonstrated in vitro that surface lipid in VLDL could be traced using the phospholipid-like fluorescent probe 1,1'-dioctadecyl-3,3, 3',3'-tetramethyl-indocarbocyanine (DiI). The core of VLDL particles was traced by fluorescently labeling apolipoprotein B with TRITC. The labeled VLDLs were perfused through rat carotid arteries, and accumulation of the fluorescently labeled VLDL components in the arterial walls was determined by quantitative fluorescence microscopy. Addition of lipoprotein lipase increased the accumulation of both DiI and TRITC by >2.3-fold. Histological examination showed that DiI and TRITC were primarily localized to the endothelial layer; however, DiI also accumulated as small "lakes" deeper in the artery, in a subendothelial position. Addition of HDL to the perfusion decreased the accumulation of surface lipid and apolipoprotein B-containing particles and eliminated the DiI lakes. Moreover, the increase in endothelial layer permeability associated with lipolysis was attenuated 21% by HDL. If VLDL surface lipid first was allowed to accumulate in the arterial wall, its subsequent rate of loss was more than twice as fast if HDL was included in the perfusate. These studies directly demonstrate atherogenic effects of VLDL lipolysis and their inhibition by HDL.

Smoking and cardiovascular disease

Mainstream and ETS exposure are strong risk factors for cardiovascular disease in men and women. The relationships between smoking and cardiovascular disease result from multiple mechanisms that interact to contribute to atherosclerosis, vascular injury, thrombosis, and vascular dysfunction. We are only now beginning to understand how smoking contributes to the genesis and progression of cardiovascular disease. Because of the complexity of the interactions between nicotine and the components of MSS, ETS, and sidestream smoke with the vasculature, it will take a great deal of time and effort to fully unravel the mechanisms by which smoking contributes to cardiovascular disease. In addition, cardiovascular risk in female smokers is complicated by hormonal variables that may contribute to greater relative risk. It is important that health care providers, educators, and policy makers recognize the changing patterns of smoking and the impact of smoking on cardiovascular disease, and continue campaigns aimed at enhancing smoking cessation in the general population and in teens. Rigorous research is needed on the changing cultural, psychosocial, and environmental factors that influence tobacco use to improve our understanding of racial/ethnic smoking patterns, and identify strategic tobacco control opportunities. The capacity of tobacco control efforts to keep pace with patterns of tobacco use and cessation depends on timely recognition of emerging prevalence and cessation patterns and the resulting development of appropriate community-based programs to address the factors involved. Smoking trends today will determine how heavy the health burden of cardiovascular disease and others will be among communities tomorrow. Programs that aim at early intervention and reflect cultural diversity will be the cornerstone in the battle against tobacco use. Continued interest in research, educational, and prevention efforts are needed to help curb the risk of cardiovascular disease from smoking in men and women.

17beta-estradiol acts separately on the LDL particle and artery wall to reduce LDL accumulation

Estrogen replacement therapy has been shown to attenuate atherogenesis, although the mechanisms for this effect are incompletely defined. Previously, we showed that 17-beta estradiol (estradiol) attenuated oxidant stress-induced increases in vascular low density lipoprotein (LDL) accumulation. It was unclear whether estradiol's effect was imparted on the lipoprotein particle or the artery wall. To examine this, we chronically treated rats with the following sex hormones: low estradiol, high estradiol, progesterone, low estradiol + progesterone, placebo, or control. Carotid arteries (n = 8/group) were isolated and perfused with fluorescently labeled LDL. Rates of LDL accumulation were measured before and after treatment with 10 ng/ml tumor necrosis factor-alpha (TNF) using quantitative fluorescence microscopy. We observed a 50% decrease in basal LDL accumulation rates (P < 0.01) and a 25% decrease in endothelial layer permeability (P < 0.01) in arteries from estradiol-treated animals. There was no effect of hormone replacement on rate of TNF-induced LDL accumulation (P = 0.451), while incubation of LDL with 65 pg/ml estradiol attenuated the TNF effect (P < 0.01). These experiments suggest two independent mechanisms of anti-atherogenic protection by estradiol: 1) decreased endothelial layer permeability; and 2) incorporation of estradiol into the LDL particle and prevention of LDL binding to the artery wall.

The clinical impact of increased sensitivity PT and APTT coagulation assays

To determine how more-sensitive prothrombin time (PT) and activated partial thromboplastin time (aPTT) reagents affected the number and distribution of abnormal test results and whether the increased sensitivity for deficiencies resulted in improved diagnosis of clinically significant coagulopathies, we retrospectively compared preoperative coagulation screening data for 140 children undergoing open heart surgery after the reagent change with a similar group of 135 before the change. The more sensitive reagents resulted in a higher rate of abnormal values, but no increase in the identification of clinically significant hemostatic abnormalities. Of 67 patients with abnormal aPTTs in the group screened with more sensitive reagents, 63 had no further workup. No patients in either group were diagnosed subsequently with a coagulopathy because of unexpected bleeding. An abnormal test result did not predict the need for perioperative blood products. We hypothesize that the high frequency of abnormal aPTTs led to physician "desensitization" about the merit of coagulation screening. Therefore, we question the usefulness of preoperative coagulation screening of the pediatric cardiac surgery patient, particularly since lasting changes in physician perception regarding the clinical significance of abnormal values may lead to missed diagnoses in other settings.

Lifestyle modification program in management of patients with coronary artery disease: the clinical experience in a tertiary care hospital

OBJECTIVES

The authors examined clinical outcomes in 71 male and female patients with coronary atherosclerosis who enrolled in a 2-year, independent-living, lifestyle modification program. The findings in 43 patients who completed the program were compared with those in 28 patients who dropped out of the program.

BACKGROUND

Clinical studies suggest that lifestyle modification of risk factors for coronary atherosclerosis reduces subsequent cardiac events but there are very few reports of the effect of these programs in patients living independently.

METHODS

Patients with diagnosed coronary atherosclerosis were managed for a 2-year period in a structured multidisciplinary program by a team that included two cardiologists, a nurse, a dietitian, an exercise physiologist, and a clinical psychologist. The overall aim of the program was to normalize or control all major reversible cardiovascular risk factors. Patients were required to participate in several weekly sessions for exercise, meditation/stress reduction training, dietary education and counseling, and participatory dinners. There was a strong emphasis on patient's self care, inclusion of support members, and regular monitoring of and feedback to patients.

RESULTS

Data comparing baseline and 2-year outcomes showed a significant reduction in body weight, dietary intake of total/saturated fat and cholesterol, serum low- and high-density lipoprotein concentration, and an increase in exercise capacity. In the compliant group, the incidence of cardiac events was 2.3% over 2 years.

CONCLUSION

Multidisciplinary lifestyle modification programs addressing cardiovascular risk factors are known to have a significant impact upon cardiac risk factors in patients with coronary atherosclerosis. Data show that these changes can be accomplished in independent-living patients in a program offered through a routine cardiology service. However, compliance is an important issue in these self-regulated programs.

17 beta-estradiol reduces glycoxidative damage in the artery wall

Glycoxidative damage in the vasculature has been linked to atherosclerotic cardiovascular disease. Estrogens protect against the development and progression of atherosclerosis. Because estrogens are potent antioxidants that also effect glucose metabolism, part of their protection against atherosclerosis could be through attenuation of glycoxidative damage in the vascular wall. In this study, we tested the hypothesis that chronic estradiol administration is associated with decreased levels of glycoxidative damage in arterial walls. We harvested and examined iliac arteries from ovariectomized, 8-month-old rats that had been implanted for 6 months with 1 of the following subcutaneous hormone pellets: low estradiol (2.5 mg estradiol), high estradiol (25 mg estradiol), P4 (200 mg progesterone), low estradiol and P4, placebo (no hormone), or control (no implant). Using pentosidine as a biomarker of glycoxidative damage, we found that all vessels from rats receiving estradiol (low estradiol, high estradiol, and low estradiol+P4) exhibited a 50% reduction in glycoxidative damage compared with P4, placebo, and control vessels (P<0.05). Consistent with this finding, we observed that estradiol-treated rats had a 30% decrease in tissue levels of hydroperoxides, a marker of oxidative stress. Finally, estradiol-treated rats had a small, but significant, decrease in plasma glucose levels (P<0.01). In summary, we report the novel finding that chronic estrogen administration is associated with significant decreases in glycoxidative damage and oxidative stress in the arterial wall. It seems likely that these actions may constitute a mechanism by which estrogen attenuates the progression of atherosclerosis.

Modified LDL-mediated increases in endothelial layer permeability are attenuated with 17 beta-estradiol

-Current research suggests that estrogen may have primary effects on the artery wall. To investigate the mechanisms of female sex hormone actions in the artery wall, we used an isolated, perfused, rat carotid artery model to examine the effects of estradiol on the rates of accumulation of normal (N-LDL) and minimally modified (MM-LDL) low density lipoprotein in ovariectomized rats. N-LDL, MM-LDL, and oxidized LDL (OX-LDL) were fluorescently labeled and perfused into individual arteries. The rate of LDL accumulation was measured by quantitative fluorescence microscopy before and after treatment with estradiol (1 nmol/L, 272 pg/mL). Estradiol had no effect on the rate of N-LDL accumulation (45+/-12 versus 48+/-15 ng cholesterol per cm2 per h). However, estradiol significantly decreased the rate of MM-LDL (240+/-48 versus 160+/-48 ng cholesterol per cm2 per h; P<0.05) and OX-LDL (191+/-53 versus 112+/-36 ng cholesterol per cm2 per h; P<0.05) accumulation. Further experiments showed that perfusion of unlabeled MM-LDL (100 microgram/mL) increased endothelial layer permeability when the rate of accumulation of a water-soluble, fluorescently labeled, reference molecule (64 000-molecular weight dextran) was determined before and after perfusion of MM-LDL (319+/-96 versus 510+/-191 ng per cm2 per h, n=6 arteries; P<0.05). Estradiol prevented the expected increase in the rate of dextran accumulation when perfused with MM-LDL (control, 415+/-49 ng per cm2 per h and MM-LDL+estradiol, 415+/-160 ng per cm2 per h). Our studies show that estradiol prevents compromise of the endothelial barrier mediated by MM-LDL and attenuates accumulation of MM-LDL in the artery wall.

17beta-estradiol reduces tumor necrosis factor-alpha-mediated LDL accumulation in the artery wall

Estrogens have direct effects on the vascular wall that may prevent the development of atherosclerosis. In particular, estrogens, such as 17beta-estradiol (estradiol), are known to have potent antioxidant activity. Tumor necrosis factor-alpha (TNF) is found in human atheroma and produces oxygen-derived free radicals. These oxygen-derived free radicals may modify low density lipoproteins (LDL) and increase LDL binding in the artery wall. We asked: 1) does TNF increase LDL accumulation in the artery wall and 2) can the TNF-mediated increase in LDL accumulation be prevented by the antioxidant activity of estradiol? Carotid arteries from ovariectomized 3-month-old rats were removed and perfused with fluorescently labeled LDL and arterial LDL flux was measured using quantitative fluorescence microscopy. In six arteries, addition of TNF (10 ng/ml) to the perfusate resulted in a 2.3-fold increase in the rate of LDL accumulation (1.50 +/- 0.37 ng/min per cm2 vs. 3.38 +/- 0.48 ng/min per cm2; P < 0.01). Estradiol (65 pg/ml) and alpha-tocopherol (6 mg/L) both attenuated TNF-mediated LDL accumulation (P < 0.05), indicating that TNF may exert its effects on LDL accumulation through cellular production of oxygen-derived free radicals. These results support an antioxidant role for estradiol in the protection against LDL accumulation in the artery wall and subsequent progression of atherosclerosis.

Reduced oxidative susceptibility of LDL from patients participating in an intensive atherosclerosis treatment program

The goal of this investigation was to determine whether participation in an atherosclerosis treatment program would reduce the oxidative susceptibility of LDL from patients with coronary artery disease. The treatment program included intensive exercise therapy, stress management, and consumption of a diet containing 10% fat. The size and antioxidant and lipid contents of LDL particles from 25 patients were analyzed at baseline and after 3 mo of therapy. The susceptibility of LDL to copper-mediated oxidation was measured by a conjugated diene assay and headspace gas chromatography (HSGC). Atherosclerosis treatment significantly reduced plasma total cholesterol and apolipoprotein B concentrations and the molar ratio of LDL cholesterol ester to apolipoprotein B (P < 0.01). The LDL content of alpha-tocopherol and beta-carotene was increased (27% and 17%, respectively, P < 0.04) and the molar ratio of LDL cholesterol ester the sum of LDL alpha-tocopherol and LDL beta-carotene decreased from 159 at baseline to 122 at 3 mo (P < 0.01). The lag phase of LDL conjugated diene formation increased 24%, whereas the maximum rate of oxidation slowed 29% (P < 0.01). As assessed by HSGC, copper-catalyzed formation of volatile lipid oxidation products was reduced 15% (P < 0.007); the reduction in volatiles was correlated with an increase in the alpha-tocopherol content of LDL (r=-0.48, P < 0.01). The principal determinants of reduced LDL oxidative susceptibility were the particle contents of alpha-tocopherol and beta-carotene. To our knowledge, this is the first report to document a reduction in LDL oxidation in coronary artery disease patients undergoing atherosclerosis-reversal therapy.

Parvovirus B19-induced anemia as the presenting manifestation of X-linked hyper-IgM syndrome

Parvovirus B19 (B19) can cause chronic anemia due to persistent infection in immunocompromised hosts who cannot produce neutralizing antibody necessary for clearing B19. Three patients with X-linked hyper-IgM syndrome (XHIM), who were all asymptomatic until they developed B19-induced chronic anemia at the ages of 8, 14, and 17 years, respectively, were found to have mutations of the CD40L gene, including a missense mutation (T254M), a nonsense mutation resulting in a new initiation codon and loss of the intracellular domain (R11X), and a splice site mutation (nt 309+2t-->a). Antibody responses to the T cell-dependent antigen, bacteriophage phiX174, were impaired, but neutralizing antibody titers were higher than in XHIM patients with classic phenotype. All 3 patients responded to intravenous immune globulin (IVIG) treatment. Certain mutations of the CD40L gene result in a mild XHIM phenotype that may become apparent following B19 infection in patients not on IVIG therapy and therefore not protected from B19 infection.

Brachydactyly type A1 with abnormal menisci and scoliosis in three generations

We report a three-generation family in which four members had brachydactyly type A1, degenerative arthritis of the knee as a complication of abnormal menisci, and variable scoliosis. Nine of the 15 individuals in the two generations preceding the proband had brachydactyly. Three of these nine had degenerative arthritis of the knee including the proband's father who had meniscal degeneration with tears. One other had radiologically confirmed discoid menisci. Of those with brachydactyly, five also had scoliosis. Although autosomal dominant inheritance of brachydactyly A1 and discoid menisci have been reported separately, cosegregation of these features in one family has not previously been described and seems to comprise a unique autosomal dominant condition. The combination of brachydactyly, meniscal abnormalities including discoid meniscus, and scoliosis suggests that this disorder represents a new osteochondrodysplasia syndrome.

Developmental toxicity induced during early stages of mammalian embryogenesis

Both a conceptual and a practical borderland between teratology and mutagenesis is early embryogenesis, the period between fertilization and gastrulation. Radiation and a variety of chemicals adversely affect the early conceptus leading to in utero mortality and malformations. The post-fertilization period of susceptibility differs from exposures of gametes, the later producing excessive pre- and peri-implantational death and low rates of fetal anomalies predominated by growth retardation. In contrast mutagen exposure of the zygote induces peri-implantational death, pan-gestational death and fetal anomalies predominated by hydrops, abdominal wall defects, and eye aberrations. The mechanism for this pathology remains unclear. These same agents produce a broader range of phenotypic anomalies during the remainder of pre-gastrulation development with anomalies overlapping those induced during organogenesis. Retinoic acid and 5-azacytidine administered prior to gastrulation produce novel malformation syndromes indicative of gene expression modification. The rates and types of defects from mutagen treatment of both gametes and the early conceptus contrast with those resulting from embryonic treatment during organogenesis, and the mechanisms are likely to differ. The pre-gastrulation period has not been explored to the extent reported during gametogenesis or organogenesis. Pre-gastrulation teratology is a new area of investigation with relevance both to reproductive toxicology and to mammalian developmental biology.

Regression of severe atherosclerotic plaque in patients with mild elevation of LDL cholesterol

BACKGROUND

Intensive risk factor reduction in patients with dyslipidemias and coronary atherosclerosis has been shown to result in alterations in coronary artery morphology and reduced clinical events. However, the impact of such interventions in populations with relatively normal levels of low-density lipoproteins (LDL) is unclear.

METHODS

To test the hypothesis that intensive risk factor reduction results in angiographic regression in patients with only mildly elevated levels of LDL, 14 patients with angiographically proven coronary atherosclerosis were entered into the University of California Davis Coronary Artery Disease Regression Program and intensively treated with pharmacologic and nonpharmacologic interventions for 2 years. Quantitative angiography was performed prior to and after 2 years of therapy to determine changes in coronary artery diameter.

RESULTS

As a result of this program, dietary fat intake was reduced by 58% and LDL fell from 120 +/- 7 mg/dL to 104 +/- 6 mg/dL (p = 0.05). The average diameter of the measured arterial locations (including all 53 stenoses and 292 nondiscrete regions) on study entry was 2.74 +/- 0.05 mm. After 24 months, there was a net increase in arterial diameter (regression) of +0.05 +/- 0.04 mm to 2.81 +/- 0.05 mm (p = 0.01). While there was no significant change in the average diameter of discrete stenoses, all 8 lesions > or = 50% initial diameter narrowing regressed, with a mean diameter change of + 0.2 mm. Conversely, only 1 of 8 mild lesions < or = 20% regressed, while 4 progressed. Intermediate lesions (20% to 50%, n = 37) had balanced progression and regression.

CONCLUSIONS

When examined as a continuous variable, there was a significant linear correlation between initial lesion severity (% stenosis) and the extent of regression (mm). Therefore, risk factor reduction (dietary therapy, exercise, psycho-social counseling, and lipid lowering therapy) in patients with only mild dyslipidemia results in angiographic regression of more severe lesions (> 50% initial stenosis), but does not prevent progression of mild lesions (< 20%). These findings demonstrate that intensive risk factor reduction in patients with only mild elevation of lipids beneficially influences the morphology of the most severe lesions.

Human mucopolysaccharidosis IIID: clinical, biochemical, morphological and immunohistochemical characteristics

Mucopolysaccharidosis IIID (MPS IIID) is one of the rarest of the MPS-III syndromes. To date, the clinical manifestations of 10 patients have been reported, the deficient N-acetylglucosamine 6-sulfatase (G6S) enzyme has been purified, and the G6S gene has been cloned, sequenced and localized. However, morphological manifestations of this condition have not been reported and the pathogenesis of the severe neurological deficits remains an enigma. In this paper we describe and correlate the clinical, biochemical and pathological observations for 2 cases of MPS IIID. We used monoclonal antibodies against heparan sulfate (HS) and GM2-ganglioside, thin layer chromatography, mass spectrometry, and morphological techniques to demonstrate the nature and the distribution of the uncatabolized substrates. The majority of the cells in various tissues showed morphological changes expected with lysosomal storage of HS. The central nervous system (CNS) was most severely affected because of the secondary storage of GM2 and GM3 gangliosides in addition to the primary accumulation of HS. The extent as well as the distribution of the diverse storage materials varied within and among different neurons as observed in MPS-III A, B, and C syndromes. This study supports the hypothesis that the neurological dysfunction and neurodegeneration common to the Sanfilippo syndromes is, in part, due to the secondary metabolic perturbations induced by HS accumulation.

Nitric oxide mediates LDL uptake in the artery wall in response to high concentrations of 17 beta-estradiol

Female sex hormones are known to affect lipoprotein flux in the artery wall and atherosclerosis. However, the mechanisms of these artery wall effects are unclear. To examine the effect of 17 beta-estradiol (estradiol) on LDL uptake in the artery wall, we developed an isolated perfused rat carotid artery model from ovariectomized rats. LDL flux in the artery wall was measured by quantitative fluorescence microscopy before and after treatment with estradiol (0.001 to 10,000 nmol/L). Dose-response experiments showed no significant difference in the rate of LDL uptake when arteries were perfused with estradiol at physiological concentrations (0.001 to 1 nmol/L) compared with control perfusions. However, higher concentrations of estradiol (10 to 10,000 nmol/L) significantly increased the rate of LDL uptake in isolated arteries. Artery lumen volume significantly increased with perfusion of estradiol (1 to 100 nmol/L) but decreased after perfusions of higher concentrations of estradiol (1000 to 10,000 nmol/L). Additional studies were performed to examine mechanisms of estradiol-mediated increases in LDL uptake. The effect of estradiol (10 nmol/L) on the rate of LDL uptake was blocked by nitric oxide synthase inhibitors. However, the estrogen receptor antagonist tamoxifen did not block the effects of estradiol on the rate of LDL uptake. Our study indicates that modulation of LDL uptake in the artery wall by estradiol is concentration dependent. High concentrations of estradiol increase LDL uptake by production of endothelium-derived nitric oxide. These observations suggest that increased nitric oxide production compromises endothelial layer barrier function to increase LDL uptake in the artery wall.

Lipoprotein lipase increases lipoprotein binding to the artery wall and increases endothelial layer permeability by formation of lipolysis products

Mechanisms responsible for the accumulation of low-density lipoprotein (LDL) were investigated in a new model, the perfused hamster aorta. To do this, we developed a method to study LDL flux in real time in individually perfused arteries; each artery served as its own control. Using quantitative fluorescence microscopy, the rates of LDL accumulation and efflux were separately determined. Perfusion of arteries with buffer plus lipoprotein lipase (LpL) increased LDL accumulation 5-fold (0.1 +/- 0.03 mV/min [control] versus 0.5 +/- 0.05 mV/min [LpL]) by increasing LDL retention in the artery wall. This effect was blocked by heparin and monoclonal antibodies directed against the amino-terminal region of apolipoprotein B (apo B). This suggests that specific regions of apo B are involved in LDL accumulation within arteries. Also, the effect of hydrolysis of triglyceride-rich lipoproteins on endothelial barrier function was studied. We compared endothelial layer permeability using a water-soluble reference molecule, fluorescently labeled dextran. When LpL was added to hypertriglyceridemic plasma, dextran accumulation within the artery wall increased > 4-fold (0.024 +/- 0.01 mV/min [control] versus 0.098 +/- 0.05 mV/min [LpL]). Under the same conditions, LpL increased LDL accumulation approximately 3-fold (0.016 +/- 0.003 mV/min [control] versus 0.047 +/- 0.013 mV/min [LpL]). Rapid efflux of LDL from the artery wall indicated that increased endothelial layer permeability was the primary mechanism during periods of increased lipolysis. Our data demonstrate two LpL-mediated effects that may increase the amount of LDL in the artery wall. These findings may pertain to the observed relationship between increased postprandial lipemia and atherosclerosis.

Ras oncogene mutations in childhood brain tumors

Although N-nitroso compounds (NNC) are ubiquitous in the human environment and are known neurocarcinogens in animal models, results of epidemiological studies have not yet convincingly associated NNCs with brain tumor occurrence in humans. Animal studies have suggested that specific codons (12, 13, and 61) in the ras family are mutable by exposure to NNCs. The purpose of this study was to measure the presence of mutations in the ras family of oncogenes in tissue from childhood brain (CB) tumors as a preliminary step toward investigating their potential use as biomarkers of chemical exposure. DNA was extracted from paraffin-embedded formalin-fixed CB tumors from tissues resected during neurosurgical operations. Using the PCR, designed RFLP-screening methods, and sequencing, we attempted to screen brain tumors from 46 children for the presence of H, K, and N-ras mutations at codons 12, 13, and 61. Screening for oncogene mutations using PCR, RFLP methods, and DNA sequencing was successfully completed for a high proportion of the available specimens. Astrocytoma specimens from three children for whom screening with PCR was successfully completed were found to contain CAA-->GAA point mutations in K-ras at codon 61. None of the specimens contained mutations at any of the other locations. These results, although preliminary, provide a potential clue for future mechanistic studies of CB tumors. The possible roles of NNCs in inducing this mutation, or of this mutation as an early or late event in tumor progression, however, remain unclear.

The ultrastructure of skin from a patient with mucopolysaccharidosis IIID

Mucopolysaccharidosis IIID (MPS-IIID) is the rarest of the MPS-III syndromes. It is caused by deficient activity of lysosomal N-acetylglucosamine-6-sulfatase (G6S). To date, the clinical and biochemical features of seven patients with MPS-IIID have been reported, but no biopsy or autopsy findings have been described. The purpose of this report is to define the ultrastructure of affected cells seen in a skin biopsy from a 14-year-old boy. The child presented with progressive mental deterioration, hyperactivity and mild to moderate dysmorphism. The diagnosis of a mucopolysaccharidosis was suggested, but the initial urine analyses were negative for elevated mucopolysaccharides, and only the third analysis showed abnormal excretion of heparan sulfate. Because of the diagnostic difficulties posed by this case, a skin biopsy was performed for morphological and biochemical studies. Numerous vacuoles were noted in Schwann cells, fibroblasts, smooth muscle cells, eccrine gland and ductal epithelium in resin-embedded sections stained with toluidine blue. Ultrastructurally, many lysosomes were distended with abundant, fibrillar material. Occasionally, lamellated membranous structures were present within the same lysosomes. These findings are consistent with those seen in other forms of MPS, in which the lysosomal storage occurs predominantly, but not exclusively, in mesenchymal cells. Furthermore, deficient activity of G6S was confirmed in cultured skin fibroblasts. This study demonstrates that electron microscopy of skin biopsies is a useful method for identification of patients with clinical features of MPS-IIID whether or not heparan sulfaturia is present.

Effect of environmental tobacco smoke on LDL accumulation in the artery wall

BACKGROUND

Previous research has shown that exposure to environmental tobacco smoke (ETS) increases the risk of atherosclerosis. To test the hypothesis that exposure to ETS increases LDL accumulation in the artery wall, we developed a model to measure the rate of LDL accumulation in individually perfused rat carotid arteries after the artery had been perfused with plasma taken from rats exposed to ETS (ETS-plasma).

METHODS AND RESULTS

Rats were exposed to ETS in a chamber in which steady-state sidestream smoke was continuously circulating. After exposure, blood from the animals was collected. Carotid arteries from unexposed rats were perfused first with normal plasma containing fluorescently labeled LDL. Then the same arteries (10 arteries from five rats) were perfused with ETS-plasma plus fluorescently labeled LDL. Photometric measurements were made during perfusion of the arteries with fluorescently labeled LDL, and rate of LDL accumulation (mV/min) and lumen volume (mV) (volume of fluorescently labeled LDL solution) were determined. Perfusion with ETS-plasma increased the rate of LDL accumulation (mean +/- SEM, 6.9 +/- 1.8 mV/min) compared with control (1.6 +/- 0.40 mV/min, P < or = .02). LDL accumulation was primarily dependent on LDL interaction with ETS-plasma rather than the interaction of ETS-plasma with the artery wall. Also, ETS-plasma significantly increased lumen volume (43.3 +/- 5.1 mV) compared with control (35.1 +/- 4.4 mV, P < or = .005).

CONCLUSIONS

Exposure to ETS acutely increased LDL accumulation in perfused arteries. Repeated exposure to ETS may represent important early events in atherogenesis.

Bone marrow transplantation in Hunter syndrome

Hunter syndrome (mucopolysaccharidosis II) is a rare X-linked disorder of mucopolysaccharide metabolism that typically progresses to severe mental retardation and death by 18 years of age. A child with Hunter syndrome received an allogeneic bone marrow transplantation from an unaffected human leukocyte antigen-identical sibling at the age of 29 months without complications. Despite full and sustained engraftment now at 70 months after transplantation, the patient's neurocognitive abilities have continued to deteriorate. In this case, replacement of defective marrow-derived macrophages by bone marrow transplantation was not effective in preventing the neurologic progression of the disease in a child with the severe phenotype of Hunter syndrome.

Exposure to ethylene oxide during the early zygotic period induces skeletal anomalies in mouse fetuses

Exposure of mouse zygotes to ethylene oxide (EtO) has been shown to increase the incidence of external malformations among late fetuses [Generoso et al. (1987) Mutat. Res., 176:267-274; Rutledge and Generoso, (1989) Teratology, 39:563-572]. The present study was designed to determine whether EtO also affects the skeletal system. We report here the effects of varying times of exposure during the zygotic period on skeletal development. Female hybrid mice were injected intraperitoneally (IP) with 125 mg/kg EtO at 1, 3, 5, or 7 hr postmating. A positive control group consisted of female mice that were injected IP with 150 mg/kg EtO once daily between the 6th to 8th days of gestation. Day 17 fetuses were double-stained for "blind" examination of skeletal deviations and degree of ossification. Zygotic exposure to EtO significantly increased loss of conceptuses as well as the incidence of external defects, skeletal anomalies, and retarded ossification in live day 17 fetuses. An increase in the number of exposed fetuses with cleft sternum was observed with the highest rate (58.5%) occurring in fetuses whose mothers were exposed to EtO 3 hours postmating. Cleft sternum was seen in only 5% of fetuses exposed during the period of organogenesis and less than 1% of control fetuses. It is concluded that zygotic exposure to EtO produces a pattern of skeletal defects that differs from those observed following treatment with EtO during organogenesis.

Expression of myogenic regulatory proteins (myogenin and MyoD1) in small blue round cell tumors of childhood

The distinction of rhabdomyosarcoma (RMS) from other small blue round cell tumors of childhood, such as Ewing's sarcoma/peripheral primitive neuroectodermal tumor (pPNET) and neuroblastoma, continues to present a diagnostic challenge to pathologists. The recent recognition of the master role of myogenic regulatory proteins in skeletal muscle commitment and differentiation, and the availability of monoclonal antibodies to two of them (myogenin and MyoD1), has prompted us to test their diagnostic utility in routinely processed, formalin-fixed, and deparaffinized tissue. Preliminary studies had demonstrated that, with the use of heat-induced epitope retrieval techniques, expression of myogenin and MyoD1 could be documented specifically in nuclei of fetal skeletal muscle by the respective antibodies. We performed a retrospective immunohistochemical analysis on 72 cases of small blue round cell tumors, including 33 RMSs, 1 metastatic myogenous Wilms' tumor, 26 Ewing's sarcomas/pPNETs, and 12 neuroblastomas. Nuclear expression of myogenin and MyoD1 were both found in 30/33 non-overlapping cases of RMS, with no significant differences in the sensitivity with respect to histological subtypes, and in 1/1 case of myogenous Wilms' tumor. None of the neuroblastomas or Ewing's sarcomas/pPNETs demonstrated positive nuclear staining with either antibody. However, most of the neuroblastomas, and occasional Ewing's sarcomas/pPNETs, showed variable fibrillary, cytoplasmic immunoreactivity with antibody to MyoD1. We conclude that, with the use of microwave-based epitope retrieval, antibodies to myogenin and MyoD1 are both useful markers for the identification of RMS among other small blue round cell tumors of childhood, but antibodies to myogenin have technical advantages over those to MyoD1, as the latter may cross-react with an unknown cytoplasmic antigen in non-muscle cells and tumors.

Quality assurance in pediatric anatomic pathology: the Society for Pediatric Pathology slide survey program

The Society for Pediatric Pathology initiated an external slide survey program in 1989 and has produced yearly challenges of 12 autopsy and surgical pathology glass slides. The history and operational difficulties are reviewed. As the program matures, it presents new challenges in the area of proficiency testing and case acquisition.

Platelet-derived growth factor A-chain expression in developing and mature human kidneys and in Wilms' tumor

Regulated expression of PDGF A-chain may be important in kidney development. We employed two polyclonal antisera to detect expression of PDGF A-chain in fetal and normal adult kidneys by immunohistochemistry. Specificity of the antisera was demonstrated by Western blots of fetal and adult kidneys, demonstrating monospecific bands at 10 to 15 kD, and by absorption studies with PDGF-A peptide. PDGF A-chain is uniformly expressed by visceral glomerular epithelial cells and the epithelial cells of the distal nephron, including collecting ducts and contiguous urothelium lining the renal pelvis, in both fetal and adult kidneys. Fetal kidneys also demonstrate expression of PDGF A-chain at the earliest stages of vesicle formation from the metanephric blastema; this expression is then only intermittently detectable in developing glomeruli until differentiation of visceral epithelial cells occurs. Fetal and mature arterial smooth muscle cells, and some express PDGF A-chain. In situ hybridization with a riboprobe made from PDGF A-chain cDNA showed close correlation of mRNA expression with protein immunohistochemistry. PDGF A-chain expression was also identified in epithelial elements of 5/6 Wilms' tumors studied. These are the first studies to localize PDGF A-chain expression in human kidney and suggest sites of activity for PDGF A-chain in development, neoplasia, and in the renal arterial sclerosis of aging.