Popliteomeniscal fascicles tears with lateral meniscus instability: outcomes of arthroscopic surgical technique at mid-term follow-up

PURPOSE

The popliteomeniscal fascicles (PMFs) are a crucial part of the posterolateral corner of the knee. They provide stability to the lateral meniscus and stabilize the joint during tibial internal rotation. The clinical diagnosis of a torn PMFs is difficult, and magnetic resonance imaging (MRI) may be inconclusive as well. The aim of the present study was to report the outcomes of a continuous series of patients affected by PMF lesions and treated with an arthroscopic repair.

METHODS

Seventeen patients (average age of 22 ± 3.6 years) with PMF lesions and lateral meniscus instability were prospectively enrolled. All patients were evaluated with clinical examination, International Knee Documentation Committee (IKDC), Lysholm and Tegner scores and 1.5 T MRI. All patients had the same arthroscopic procedure consisting of meniscal repair with an all-inside meniscal repair system (mean 2.2 ± 0.77 anchors) and followed with the same postoperative protocol.

RESULTS

All patients were available at a mean follow-up of 68 ± 24 months (range 49-84 months). Mean IKDC increased from 60.2 ± 13.5 to 83.1 ± 12, mean Lysholm score improved from 56.7 ± 8.2 to 89.8 ± 3.2, and mean Tegner score improved from 2.9 ± 1.3 to 6.5 ± 2. No intraoperative or postoperative complications were reported. MRI evaluation at 6-month follow-up showed successful healing of the menisco-popliteal fascicles in all cases.

CONCLUSIONS

The diagnosis and treatment of tears of the PMFs is still debated. Diagnostic confirmation of tearing of the PMFs is usually determined at the time of arthroscopy. Meniscal repair with an all-inside meniscal repair system appears to be an excellent treatment option, since it yields good functional results at mid-term follow-up, no local complications, and complete radiographic healing at 6-month follow-up MRI. Further studies are needed to confirm these promising early results.

LEVEL OF EVIDENCE

Case series, 4.

Hybrid coracoclavicular and acromioclavicular reconstruction in chronic acromioclavicular joint dislocations yields good functional and radiographic results

PURPOSE

Optimal treatment of chronic unstable acromioclavicular (AC) joint dislocations (stage 3-5 according the Rockwood classification) is still debated. Anatomic coracoclavicular (CC) reconstruction is a reliable option in terms of two-dimensional radiographic reduction, clinical outcomes, and return to sports, but there remain concerns regarding anterior-posterior stability of the AC joint with CC ligament reconstruction alone. The aim of the present study was to describe the mid-term results of a new hybrid technique with CC and AC ligament reconstruction for chronic AC joint dislocations.

METHODS

Twenty-two patients surgically treated for chronic AC joint dislocations (grade 3 to 5) were retrospectively reviewed. All patients were assessed before surgery and at final follow-up with the Constant-Murley score (CMS) and the American Shoulder and Elbow Surgeons (ASES) score. The CC vertical distance (CCD) and the CCD ratio (affected side compared to unaffected side) were measured on Zanca radiographs preoperatively, at 6 months postop and at final follow-up. The same surgical technique consisting in a primary fixation with a suspensory system, coracoclavicular ligaments reconstruction with a double loop of autologous gracilis and acromioclavicular ligaments reconstruction with autologous coracoacromial ligament was performed in all cases.

RESULTS

Twenty-two shoulders in 22 patients (19 males and 3 females) were evaluated with a mean age of 34.4 ± 9 years at the time of surgery. The mean interval between the injury and surgery was 53.4 ± 36.7 days. The mean duration of postoperative follow-up was 49.9 ± 11.8 months. According to the Rockwood classification, there were 5 (22.6%) type-III and 17 (77.2%) type-V dislocations. Mean preoperative ASES and CMS were 54.4 ± 7.6 and 64.6 ± 7.2, respectively. They improved to 91.8 ± 2.3 (p = 0.0001) and 95.2 ± 3.1 (p = 0.0001), respectively at final FU. The mean preoperative CCD was 22.4 ± 3.2 mm while the mean CCD ratio was 2.1 ± 0.1. At final FU, the mean CCD was 11.9 ± 1.4 mm (p = 0.002) and the mean CCD ratio was 1.1 ± 0.1 (p = 0.009). No recurrence of instability was observed. One patient developed a local infection and four patients referred some shoulder discomfort. Heterotopic ossifications were observed in three patients.

CONCLUSIONS

The optimal treatment of chronic high-grade AC joint dislocations requires superior-inferior and anterior-posterior stability to ensure good clinical outcomes and return to overhead activities or sports. The present hybrid technique of AC and CC ligaments reconstruction showed good clinical and radiographic results and is a reliable an alternative to other reported techniques.

LEVEL OF EVIDENCE

Level IV.

Soccer players show the highest seasonal groin pain prevalence and the longest time loss from sport among 500 athletes from major team sports

PURPOSE

Groin pain is a widely recognized medical issue among athletes. Groin pain can affect both player and team performance and sometimes can be a career-ending injury. The aim of this study was to assess seasonal groin pain prevalence and the average seasonal time loss from sport for each injury in different team sport athletes. The hip and groin functionality at the beginning of the following season was also investigated.

METHODS

A cross-sectional study was undertaken on 600 team sport athletes (soccer, futsal, basketball, volleyball, and water polo players). The seasonal prevalence of groin pain, level of competition (professional and non-professional), time loss, and concomitant injuries in addition to groin pain were reported and analyzed. The Copenhagen Hip and Groin Outcome Score (HAGOS) was used to assess hip and groin pain and function related to sport and activity.

RESULTS

Among the 506 (84%) players included, 123 players (24.3%) reported groin pain. Overall, soccer players reported the highest groin pain prevalence (32.5%) followed by futsal (25.5%), basketball (25.2%), water polo (17.6%) and volleyball players (13.6%). Professional soccer, futsal and basketball athletes showed higher groin pain prevalence in comparison with non-professional athletes (p = 0.02, p = 0.005 and p = 0.004, respectively). The mean time loss from sport due to groin pain was 60.3 ± 66 days in soccer, 41.1 ± 16.6 days in futsal, 31.5 ± 18 days in water polo, 37.2 ± 14.2 days in basketball and 50.8 ± 24.6 days in volleyball. Significantly lower HAGOS values were found in athletes with groin pain for all sports evaluated compared to athletes with no groin pain history (p =  0.0001). Longer time loss from sport was correlated with lower HAGOS values in soccer (p = 0.002) and futsal (p = 0.002) players with groin pain. Concomitant injuries were correlated with lower HAGOS values in water polo players (p = 0.03).

CONCLUSIONS

Seasonal groin pain occurs in as many as one in four team sport athletes. Soccer players show the highest groin pain prevalence and the longest time loss from sport. Professional athletes report higher prevalence of groin pain in comparison with non-professional athletes. HAGOS appears to be a valid outcome instrument to measure groin pain, correlating with both time loss from sport and concomitant injuries in athletes.

LEVEL OF EVIDENCE

Level IV.

The Rising Moon sign is specific and sensitive in the diagnosis of bucket handle tears of the medial meniscus

PURPOSE

Bucket handle tears of the meniscus are common and can lead to locking, extension deficit and functional impairment. The diagnosis is determined by a combination of physical examination and imaging, but in some cases the diagnosis may be challenging since specific clinical tests are lacking. The aim of the present study was to assess the value of a new clinical test, the elective pain at the anterior aspect of the joint line (defined as the "Rising Moon sign") in the diagnosis of bucket handle tears of the medial meniscus.

METHODS

Forty patients treated for a bucket handle of the medial meniscus were enrolled as the study group and were compared to a matched group of 40 patients with a posterior horn tear of the medial meniscus and 50 healthy subjects. The following aspects were investigated in the groups: body mass index, extension deficit, pain at the posterior aspect of the joint line (PPJL), at the middle joint line (PMJL), at the anterior join line (PAJL) and at combined hyperflexion of the knee and external rotation of the foot (PHE). Pain at the anterior joint line (PAJL) was defined as the Rising Moon sign.

RESULTS

In the bucket handle group the average flexion contracture was 12° (0-30°). The average PPJL was one (0-2), the average PMJL was 1.6 (0-3), PAJL was 2.5 (1-3) and PHE was 1.6 (1-2). In the posterior horn tear group the average flexion contracture was 0.9° (- 10 to 5°). The average PPJL was 2.2 (1-3), the average PMJL was 1.4 (0-3), PAJL was 0.6 (0-2) and PHE was 2.5 (1-3). The rising moon showed 95% sensitivity and 98% specificity in the diagnosis of bucket handle tears. In addition it showed a positive predictive value of 97.4% and negative predictive value of 96%. Finally it also demonstrated high inter-observer reliability (0.905).

CONCLUSIONS

The "Rising Moon" sign has shown to be highly predictive for bucket handle tears of the medial meniscus with very high specificity and sensitivity. In addition it is easy to perform with very high inter-observer reliability.

LEVEL OF EVIDENCE

Level IV.

Shoulder arthroplasty to address the sequelae of anterior instability arthropathy and stabilization procedures: systematic review and meta-analysis

PURPOSE

Chronic anterior glenohumeral joint instability is a common situation and can lead to progressive cartilage deterioration and ultimately instability arthopathy. Progressive cartilage deterioration can occur despite conservative or surgical treatment and the sequelae of these conditions are often addressed with total shoulder arthroplasty. Aims of the present study were to analyze the available literature to describe the technical aspects of this particular operation and to report outcomes and complication rates. The hypothesis was that shoulder arthropalsty in the sequelae of instability had lower outcomes and higher complication rates than arthroplasties for primary arthritis.

METHODS

A systematic review of the literature was performed, in accordance with the PRISMA guidelines. PubMed, Ovid, Cochrane Reviews, and Google Scholar were comprehensively searched using a combination of the following keywords: shoulder arthroplasty, reverse shoulder arthroplasty, dislocation arthropathy, capsulorrhaphy arthropathy and stabilization procedures.

RESULTS

Thirteen studies with 365 patients met inclusion criteria. Since 13 patients were lost to follow-up, 352 were reviewed at an average follow-up of 53.4 months. The average Constant-Murley (CM) and American Shoulder and Elbow Society (ASES) scores improved from 35.6 and 35.7 to 72.7 and 77, respectively. The overall complication rate was 25.7% and the reoperation rate was 18.5%. Radiographs at follow-up revealed radiolucent lines on the humerus in 12.4% of cases and radiolucent lines or notching on the glenoid side in 22.7% of cases. The average Methodological Index for Non-randomized Studies Score (MINORS) was 12.9 for non-comparative studies and 21.3 for comparative studies.

CONCLUSION

Shoulder arthroplasty to address the sequelae of instability arthropathy and stabilization procedures can be a challenging procedure as a consequence of the distorted anatomy and severe glenohumeral joint pathology. Complication and reoperation rates are higher compared to shoulder arthroplasty for primary glenohumeral joint arthritis; however, the difference is not statistically significant. When reverse shoulder arthroplasties (RSA) were considered as a subgroup and compared to anatomic shoulder replacements (total shoulders and hemiarthroplasties), they showed a lower revision rate.

Comparable clinical and functional outcomes after anterior cruciate ligament reconstruction over and under 40 years of age

PURPOSE

The aim of the present meta-analysis was to update the literature on the outcomes and complications of ACL reconstruction in patients aged 40 years and older. It has been hypothesized that patients older than 40 years of age may have comparable clinical outcomes to those of younger patients.

METHODS

A systematic review of articles from 1996 to 2018 was completed using Pubmed, Medline, Cochrane Reviews, and Google Scholar databases using the keyword terms "anterior cruciate ligament reconstruction" and "middle-aged OR elderly OR over 40 OR age factors." Functional and clinical outcomes (International Knee Documentation Committee, Lysholm and Tegner score and KT-1000 arthrometer), complication and graft failure rate were evaluated.

RESULTS

Eleven articles met inclusion criteria. In total, 306 middle-aged patients and 566 younger patients were included in this study. The mean age of patients > 40 was 49 ± 7 (range 40-75) years with a mean follow-up of 25 ± 9 months (range 12-68). The mean age of younger patients was 26 ± 2.7 (range 15-39) years with a mean post-operative follow-up of 26.7 ± 11.5 months (range 3-64). The results were slightly higher (but no significantly different) towards the younger group in terms of objective IKDC (P = n.s.), Lysholm (P = n.s.) and Tegner (P = n.s.) scores and knee laxity assessment (P = n.s.). Complication rate (P = n.s.) and graft failure (P = n.s.) were low even in this cohort.

CONCLUSIONS

The present meta-analysis shows that patients older than 40 years achieve comparable clinical outcomes to those of younger patients following primary ACL reconstruction. This evidence may push the surgeons toward a more aggressive approach in this specific cohort of patients.

LEVEL OF EVIDENCE

III.

Early Outcomes and Perioperative Complications of the Arthroscopic Latarjet Procedure: Systematic Review and Meta-analysis

BACKGROUND

The arthroscopic Latarjet-Bristow procedure is emerging as a reliable alternative to the open procedure. The reduced soft tissue damage with potential advantages of early pain control and functional recovery is attractive. However, the operation is technically more demanding, and there are concerns regarding the potential for increased recurrence and complication rates.

PURPOSE

To evaluate the available literature focusing on the reported functional outcomes and complications of the arthroscopic Latarjet procedure and compare them with the open procedure.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A comprehensive systematic review was performed with the keywords "arthroscopy," "arthroscopic," "Latarjet," and "Bristow," with no limit regarding the year of publication. The review was limited to the English-language articles, and each article was evaluated with a modified MINORS (methodological index for nonrandomized studies) scoring system.

RESULTS

Fourteen studies met the inclusion criteria and were included in the review. Overall, 813 patients met inclusion criteria, with a mean follow-up of 24.5 months. The mean Walch-Duplay and Rowe scores were 89.6 and 90.2, respectively. The overall complication rate was 16.5%; intraoperative conversion to open surgery, 2%; recurrence, 2.5%; and revision surgery, 5.6%. When only comparative studies were considered, the overall complication rates were 23.7% (arthroscopically) and 15.3% (open). The recurrence and revision surgery rates were 6.5% and 5.7% in the study group, while the corresponding values in the control group were 4% and 2.9%. The mean MINORS score was 14.5 (11.6 for noncomparative studies and 19 for comparative studies).

CONCLUSION

The arthroscopic Latarjet-Bristow procedure is reliable. Outcomes are satisfactory, with less pain and faster recovery in the first postoperative week. However, the procedure is technically demanding, and higher rates of complications and reoperations should be expected. Finally, the arthroscopic operation is much more expensive in terms of implanted materials than the open procedure.

Cross-cultural adaptation and validation of the Italian versions of the Kujala, Larsen, Lysholm and Fulkerson scores in patients with patellofemoral disorders

BACKGROUND

The Kujala, Fulkerson, Larsen and Lysholm questionnaires have been demonstrated to be reliable and sensitive in assessing patients with patellofemoral pathology. The purpose of this study is to translate and cross-culturally adapt into Italian the English versions of the Kujala, Fulkerson, Larsen and Lysholm questionnaires, and undertake reliability and validity evaluations of the Italian versions of these scores in patients with patellofemoral pathology.

MATERIALS AND METHODS

The cross-cultural adaptation process was carried out following the simplified Guillemin criteria. The questionnaires were administered to 63 patients with either patellar instability or painful patella syndrome. To assess the validity of the questionnaires, they were compared with the Oxford knee score. The questionnaires were administered to a subsample of 33 patients 5 days later to assess test-retest reliability.

RESULTS

The interclass coefficient correlation was 0.96 for the Kujala score, 0.92 for the Larsen score, 0.96 for the Lysholm score, 0.94 for the Fulkerson score (P < 0.01), and 0.83 for the Oxford score. Pearson's correlation was0.96 between the Kujala and Oxford scores, 0.90 between the Larsen and Oxford scores, 0.94 between the Lysholm and Oxford score, and 0.93 between the Fulkerson and Oxford scores. Responsiveness, calculated by standardized response mean, was 1.2, and effect size was 1.4.

CONCLUSIONS

The Italian versions of the Kujala, Larsen, Lysholm and Fulkerson scoring systems were shown to be equivalent to their English versions and demonstrated good validity, reliability and responsiveness to surgical treatment of patellofemoral pathology. To the best of the authors' knowledge, this is the first attempt to adapt four of the most common patellofemoral-specific scoring scales to the Italian language.

LEVEL OF EVIDENCE

Level II.

A novel broth medium for enhanced growth of Francisella tularensis

Francisella tularensis is a fastidious organism that requires a lengthy incubation time in liquid growth media for detection. The objective of this study was to develop a medium formulation using readily available supplements that enhanced early growth of F. tularensis. Francisella tularensis live vaccine strain was used to evaluate the growth responses for each of the media formulations tested. Growth in brain heart infusion broth supplemented with 2% Vitox, 10% Fildes and 1% histidine (BVFH) resulted in a significant increase in growth after 8 h incubation compared to other media formulations tested (P < 0·001). Virulent strains of F. tularensis grown in BVFH medium demonstrated similar enhanced early growth. Cell densities of 3·9-5·2 log₁₀ CFU per ml were obtained after 24 h of growth in BVFH from a 1-2 cell ml^-1 starting inoculum of the virulent Type A Schu4 strain, indicating the suitability of this medium in rapidly amplifying low starting titres of F. tularensis. Collectively, these results indicate that the novel formulation of the BVFH medium was capable of producing enhanced growth response for F. tularensis.

SIGNIFICANCE AND IMPACT OF THE STUDY

The need for rapid cultivation of Francisella tularensis is essential for detection and monitoring during natural outbreak events or intentional bioterrorism attacks. The addition of selected supplements into the base medium BHI (BVFH) developed in this study enhanced growth of F. tularensis Type A1, A2 and B strains compared to BHI alone. Growth of these organisms in BVFH will allow for improved response time should a natural or intentional contamination event occur.

Lateral tibial plateau autograft in revision surgery for failed medial unicompartmental knee arthroplasty

PURPOSE

Revision surgery for failed unicompartmental knee arthroplasty (UKA) with bone loss is challenging. Several options are available including cement augmentation, metal augmentation, and bone grafting. The aim of the present study was to describe a surgical technique for lateral tibial plateau autografting and report mid-term outcomes.

METHODS

Eleven consecutive patients (median age 69.5 years) affected by posteromedial tibial plateau collapse after medial UKA were enrolled in the present study. The delay between UKA and revision surgery was 21 months (range 15-36 months). All patients were revised with a cemented posterior-stabilized implant, with a tibial stem. Medial tibial plateau bone loss was treated with an autologous lateral tibial plateau bone graft secured with two absorbable screws. All patients were evaluated with the Oxford Knee Score (OKS), visual analogue scale for pain (VAS), and complete radiographic evaluation.

RESULTS

At a median follow-up of 60 months (range 36-84 months), the OKS improved from 21.5 (range 16-26) to 34.5 (range 30-40) (p < 0.01) and the median VAS score improved from 8.0 (range 5-9) to 5.5 (range 3-7) (p < 0.01). No intraoperative complications were recorded. Partial reabsorption of the graft was observed in two cases at final follow-up.

CONCLUSION

Lateral tibial plateau bone autograft is an alternative to metal wedge or cement augments in the treatment of medial plateau collapse after UKA. Primary fixation of the tibial plateau autograft can be achieved with absorbable screws and a tibial-stemmed implant. Further comparative studies with a larger series may be helpful to draw definitive conclusions.

LEVEL OF EVIDENCE

Case series, Level IV.

The role of wound closure in total knee arthroplasty: a systematic review on knee position

PURPOSE

Post-operative range of motion (ROM) is one of the most important parameters to assess, following total knee arthroplasty (TKA). The aims of the present systematic review were to analyse the available literature and determine if closing the knee in flexion or extension influences post-operative ROM, clinical outcomes, and complications following TKA.

METHODS

A systematic review was performed using the keywords "total knee arthroplasty", "total knee replacement", and "wound closure" or "joint closure" or "extension" or "flexion" with no limit regarding the year of publication. The review was limited to the English-language articles, and each article was evaluated with a modified Coleman Methodology Score (mCMS).

RESULTS

Six articles met inclusion criteria. The initial cohort included 202 TKAs in the flexion group and 201 in the extension group. Three hundred and ninety-seven TKAs were evaluated with an average follow-up of 8 months. There was no statistical difference (n.s.) between the two groups in terms of the average post-operative flexion. There were no statistical differences between the two groups regarding post-operative functional scores and VAS scores (n.s.). The average mCMS was 70.9, indicating good methodological quality in the included studies.

CONCLUSIONS

The findings of the present review did not show any statistically significant differences in terms of post-operative flexion ROM, functional scores, or complications related to the position of the knee at the time of joint and wound closure during TKA. There is no clear advantage to either closure method based on the currently available evidence, and therefore, this choice should be based on surgeon preference.

Cross-cultural adaptation and validation of the Italian version of the Western Ontario Osteoarthritis of the Shoulder index (WOOS)

BACKGROUND

The Western Ontario Osteoarthritis of the Shoulder index (WOOS) has been introduced as a disease-specific quality of life measurement in patients with glenohumeral arthritis. The aim of the present study was to perform a cross-cultural adaptation of the English version of the WOOS to Italian and to assess its validity, reliability and responsiveness in patients with glenohumeral joint osteoarthritis treated conservatively.

MATERIAL AND METHODS

The adaptation process was carried out following the simplified Guillemin criteria. The English version was translated into Italian by two bilingual orthopaedic surgeons and then translated back into English by two different bilingual orthopaedic surgeons. The original version was compared with the back-translation. The questionnaire was prospectively administered to 30 patients with glenohumeral osteoarthritis at baseline and again after 5 days for retest reliability. After 6 months of conservative treatment, the responsiveness of the questionnaire was assessed in a subsample of 20 patients. The level of statistical significance was set at 0.05.

RESULTS

The interclass correlation coefficient between test and retest of the WOOS was 0.99 (P < 0.001). Pearson's correlation coefficient between the WOOS and disability of the arm, shoulder and hand (DASH) preoperatively was 0.73 (P < 0.01) and the correlation between the changes of score for the WOOS and DASH was 0.75 (P < 0.01). There were no floor or ceiling effects. Responsiveness, calculated by standardized response mean, was 1.1 and effect size was 1.3.

CONCLUSIONS

The Italian version of the WOOS questionnaire has shown to be equivalent to its English version and demonstrated good validity, reliability and responsiveness to conservative treatment of glenohumeral osteoarthritis.

LEVEL OF EVIDENCE

Level II.

Bone block procedures in posterior shoulder instability

PURPOSE

Posterior shoulder dislocation is often associated with bone defects. Surgical treatment is often necessary to address these lesions. The aim of the present systematic review was to analyse the available literature concerning bone block procedures in the treatment of bone deficiencies following posterior dislocation. In addition, the methodology of the articles has been evaluated through the Coleman methodology score.

METHODS

A systematic review of the literature was performed using the keywords "posterior shoulder instability", "posterior shoulder dislocation", "bone loss", "bone defect", "bone block", and "bone graft" with no limit regarding the year of publication. All English-language articles were evaluated using the Coleman methodology score.

RESULTS

Fifty-four articles were identified, and 13 articles met inclusion criteria. The initial cohort included 208 shoulders, and 182 were reviewed at an average follow-up of 72.7 months (±55.2). The average Coleman score was 57.2 (±8.0). The most lacking domains were the size of study population, the type of study, and the procedure for assessing outcomes. All the articles showed an increase in the outcome scores. Radiographic evaluation revealed degenerative changes such as osteoarthritis and graft lysis in most of the series.

CONCLUSIONS

This review confirms the lack of studies with good methodological quality. However, bone grafting is a reliable option since significant improvement in all scores is reported. Although a low incidence of recurrence is generally described, there are concerns that the results may deteriorate over time as evidenced by graft lysis and glenohumeral osteoarthritis in up to one-third of patients.

LEVEL OF EVIDENCE

Systematic review, Level IV.

Obesity Increases Early Complications After High-Energy Pelvic and Acetabular Fractures

Elevated body mass index has been identified as a potential risk factor for complications in operatively treated pelvic trauma. Although obesity is an independent risk factor for morbidity and mortality following high-energy blunt force trauma, there is little information on the immediate complications following isolated pelvic and acetabular fractures in obese patients with trauma. The authors hypothesized that obesity (body mass index ≥30 kg/m(2)) is a risk factor for complications in both operative and nonoperative pelvic and acetabular fractures. The authors conducted a 5-year retrospective data collection of all patients with isolated pelvic and acetabular fractures presenting to a Level I trauma center, excluding pediatric (age <18 years) patients, those with ballistic injuries, and those with concomitant long bone fractures or an Abbreviated Injury Scale score of greater than 2 in any other body region. Complications during the immediate hospitalization period were identified by the institution's Trauma Registry of the American College of Surgeons database, including wound infection, dehiscence, deep venous thrombosis, pulmonary embolus, pneumonia, and development of decubitus ulcers. Mean body mass index was 27.4 ± 6.8 kg/m(2), with 68 (27.0%) obese patients. Mean body mass index of patients with complications was significantly higher (31.9 ± 9.5 vs 27.0 ± 6.5 kg/m(2); P=.001). Logistic regression showed that obesity was a significant risk factor for complications (odds ratio, 2.87; 95% confidence interval, 1.02-8.04), after adjusting for age (odds ratio, 1.03; 95% confidence interval, 1.01-1.06) and Injury Severity Score (odds ratio, 1.20; 95% confidence interval, 1.10-1.32). Obesity is associated with increasing complications following operative fixation of pelvic and acetabular fractures. However, it is important to recognize that even nonoperative management of pelvic and acetabular fractures in obese patients can have early complications. This study showed a significant obesity-related risk of complications after trauma in both operative and nonoperative pelvic injuries.

Novel treatment strategies for schizophrenia from improved understanding of genetic risk

Recent years have seen significant advances in our understanding of the genetic basis of schizophrenia. In particular, genome-wide approaches have suggested the involvement of many common genetic variants of small effect, together with a few rare variants exerting relatively large effects. While unequivocal identification of the relevant genes has, for the most part, remained elusive, the genes revealed as potential candidates can in many cases be clustered into functionally related groups which are potentially open to therapeutic intervention. In this review, we summarise this information, focusing on the accumulating evidence that genetic dysfunction at glutamatergic synapses and post-synaptic signalling complexes contributes to the aetiology of the disease. In particular, there is converging support for involvement of post-synaptic JNK pathways in disease aetiology. An expansion of our neurobiological knowledge of the basis of schizophrenia is urgently needed, yet some promising novel pharmacological targets can already be discerned.

The 2010 Royal Australasian College of Physicians' policy statement 'Circumcision of infant males' is not evidence based

Infant male circumcision (MC) is an important issue guided by Royal Australasian College of Physicians (RACP) policy. Here we analytically review the RACP's 2010 policy statement 'Circumcision of infant males'. Comprehensive evaluation in the context of published research was used. We find that the Statement is not a fair and balanced representation of the literature on MC. It ignores, downplays, obfuscates or misrepresents the considerable evidence attesting to the strong protection MC affords against childhood urinary tract infections, sexually transmitted infections (human immunodeficiency virus, human papilloma virus, herpes simplex virus type 2, trichomonas and genital ulcer disease), thrush, inferior penile hygiene, phimosis, balanoposthitis and penile cancer, and in women protection against human papilloma virus, herpes simplex virus type 2, bacterial vaginosis and cervical cancer. The Statement exaggerates the complication rate. Assertions that 'the foreskin has a functional role' and 'is a primary sensory part of the penis' are not supported by research, including randomised controlled trials. Instead of citing these and meta-analyses, the Statement selectively cites poor quality studies. Its claim, without support from a literature-based risk-benefit analysis, that the currently available evidence does 'not warrant routine infant circumcision in Australia and New Zealand' is misleading. The Statement fails to explain that performing MC in the neonatal period using local anaesthesia maximises benefits, safety, convenience and cost savings. Because the RACP's policy statement is not a fair and balanced representation of the current literature, it should not be used to guide policy. In the interests of public health and individual well-being, an extensive, comprehensive, balanced review of the scientific literature and a risk-benefit analysis should be conducted to formulate policy.

Biological basis for the protective effect conferred by male circumcision against HIV infection

Here we provide an up-to-date review of research that explains why uncircumcised men are at higher risk of HIV infection. The inner foreskin is a mucosal epithelium deficient in protective keratin, yet rich in HIV target cells. Soon after sexual exposure to infected mucosal secretions of a HIV-positive partner, infected T-cells from the latter form viral synapses with keratinocytes and transfer HIV to Langerhans cells via dendrites that extend to just under the surface of the inner foreskin. The Langerhans cells with internalized HIV migrate to the basal epidermis and then pass HIV on to T-cells, thus leading to the systemic infection that ensues. Infection is exacerbated in inflammatory states associated with balanoposthitis, the presence of smegma and ulceration - including that caused by infection with herpes simplex virus type 2 and some other sexually transmitted infections (STIs). A high foreskin surface area and tearing of the foreskin or associated frenulum during sexual intercourse also facilitate HIV entry. Thus, by various means, the foreskin is the primary biological weak point that permits HIV infection during heterosexual intercourse. The biological findings could explain why male circumcision protects against HIV infection.

Molecular characterization of renin-angiotensin system components in human intrauterine tissues and fetal membranes from vaginal delivery and cesarean section

A prorenin-angiotensin system (RAS) could, via the (pro)renin receptor (ATP6AP2), have various effects in human intrauterine tissues, either directly by prorenin/ATP6AP2 cell signaling, or indirectly via angiotensin II and/or angiotensin 1-7. Here we describe RAS components in fetal membranes, decidua and placenta collected at elective cesarean section (non-laboring), after spontaneous delivery (after labor, n = 38), and in myometria (n = 16) from elective (non-laboring) or emergency cesarean (laboring) deliveries. Angiotensinogen (AGT), angiotensin-converting enzyme 1 and 2 (ACE; ACE2), angiotensin receptor 1 and 2 (AGTR1; AGTR2) and angiotensin 1-7 receptor (MAS1) mRNAs were measured by qRT-PCR and proteins were localized by immunohistochemistry. In myometrium, prorenin (REN), ATP6AP2, and downstream signaling proteins zinc finger and BTB domain-containing protein 16 (ZBTB16), transforming growth factor-β1 (TGFβ1) and prostaglandin-endoperoxide synthase 2 (PTGS2) mRNAs were also measured. RAS mRNAs, except AGTR1 and AGTR2, were abundant in decidua and lowest in amnion compared to the other tissues. ACE, AGT and PTGS2 mRNAs were higher in laboring than non-laboring myometrium, suggesting that the myometrial RAS is involved in labor. Angiotensinogen and prorenin staining in amnion, chorion and decidua was pervasive despite their mRNAs being low in amnion and chorion. In placenta, prorenin, angiotensinogen and AGTR2 were present in syncytiotrophoblasts, ACE was in fetal endothelium, while ACE2 distribution was diffuse. AGTR1 and AGTR2 mRNAs and proteins were abundant. No differences were evident in the staining patterns with labor. These results are consistent with the hypothesis that fetal vascular ACE might contribute angiotensin II to the fetus, whilst syncytial ACE2 might hypothetically have a role in converting angiotensin II to angiotensin 1-7 in maternal blood.

Contrasting roles of neuronal Msk1 and Rsk2 in Bad phosphorylation and feedback regulation of Erk signalling

Activated extracellular-signal-regulated kinase (Erk) phosphorylates and activates downstream kinases including ribosomal S6 kinase 2 (Rsk2/RPS6KA3) and mitogen- and stress-activated kinase 1 (Msk1, RPS6KA5). Rsk2 plays an important role in neuronal plasticity, as patients with Coffin-Lowry syndrome, where Rsk2 is dysfunctional, have impaired cognitive function. However, the relative role of neuronal Rsk2 and Msk1 in activating proteins downstream of Erk is unclear. In PC12 cells and in cortical neurones, the calcium ionophore A23187-induced phosphorylation of Erk, Msk1, Rsk2 and also the Bcl-2-associated death protein (Bad), which protects against neurotoxicity. Specific knockdown of Msk1 with small interfering RNA reduced the ability of A23187 to induce Bad phosphorylation in both PC12 cells and cortical neurones. Conversely, specific knockdown of Rsk2 potentiated Bad phosphorylation following A23187 treatment, and also elevated Erk phosphorylation in both cell types. This indicates that Msk1 rather than Rsk2 mediates neuronal Bad phosphorylation following Ca(2+) influx and implicates Rsk2 in a negative-feedback regulation of Erk activity.

Selective increases in the cytokine, TNFalpha, in the prefrontal cortex of PCP-treated rats and human schizophrenic subjects: influence of antipsychotic drugs

The psychotomimetic drug phencyclidine (PCP) induces symptoms closely related to those of schizophrenia in humans. In order to test the hypothesis that cytokines may be involved in the aetiology and treatment of schizophrenia, this study investigated the levels of cytokine mRNAs in rat brain after acute and chronic administration of PCP, in the presence and absence of antipsychotic drugs. The levels of the mRNAs encoding TNF, IL-2, IL-6, TGF 1, 2, 3, IL-3 and GM-CSF were measured in the prefrontal cortex, cortex, hippocampus, ventral and dorsal striatum regions of male hooded Long Evans rats after acute drug administration. Antipsychotic drugs and PCP significantly reduced the levels of TNF in the prefrontal cortex compared to vehicle-treated animals, whilst other cytokines remained unchanged. In addition, significant reductions in the levels of TNF mRNA in the prefrontal cortex still occurred 24h after acute PCP administration. However, levels of TNF mRNA were restored to control values after chronic PCP treatment, whereas increased expression was detected in animals co-administered with haloperidol. Levels of TNF mRNA were also found to be significantly increased in the prefrontal cortex of schizophrenic subjects. The relationship between TNF levels and schizophrenia are discussed.

Divergent regulation of Pyk2/CAKbeta phosphorylation by Ca2+ and cAMP in the hippocampus

Proline-rich tyrosine kinase 2 (Pyk2) is activated in neurones following NMDA receptor stimulation via PKC. Pyk2 is involved in hippocampal LTP and acts to potentiate NMDA receptor function. Elevations of intracellular Ca2+ and cAMP levels are key NMDA receptor-dependent triggering events leading to induction of hippocampal LTP. In this study, we compared the ability of A23187 (Ca2+ ionophore) or forskolin (adenylate cyclase activator) to modulate the phosphorylation of Pyk2 in rat hippocampal slices. Using an immunoprecipitation assay, phosphorylated Pyk2 levels were increased following treatment with A23187, levels peaking at around 10 min. Staurosporine, at concentrations inhibiting conventional and novel isoforms of PKC, and chelerythrine, at concentrations inhibiting the atypical PKC isoform PKMxi, were compared for their ability to attenuate the effect of A23187. Exposure of acute hippocampal slices to either chelerythrine or staurosporine completely blocked enhanced phosphorylation of Pyk2 by A23187, suggesting a possible involvement of PKMxi and typical PKCs in Pyk2 activation by Ca2+. In contrast, application of forskolin reduced phosphorylated Pyk2 below basal levels, suggesting that cAMP inhibits Pyk2. These results implicate Ca2+ and multiple forms of PKC in the activation of Pyk2 downstream of NMDA receptors and suggest that cAMP-dependent processes exert a suppressive action on Pyk2.

N-Methyl-D-aspartate and Brain-Derived Neurotrophic Factor Induce Distinct Profiles of Extracellular Signal-Regulated Kinase, Mitogen- and Stress-Activated Kinase, and Ribosomal S6 Kinase Phosphorylation in Cortical Neurons

Stimulation of N-methyl-D-aspartate (NMDA) receptors is believed to underlie long-term memory formation, and excessive NMDA receptor activation has been linked to several neuropathological conditions. Phosphorylation and activation of p42/44 mitogen-activated protein kinase (ERK) is believed to mediate many of these effects, but the downstream targets of ERK in response to NMDA activation have not been determined. In primary cultures of rat cortical neurons, we found that NMDA was able to elevate phosphorylation of mitogen- and stress-activated kinase 1 (MSK1) as well as ERK. Likewise, brain-derived neurotrophic factor (BDNF) treatment increased phosphorylation of MSK1 and ERKs. The NMDA-induced MSK1 phosphorylation was sensitive to the MEK inhibitor 2'-amino-3'-methoxyflavone (PD98059) and the p38 inhibitor 4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole (SB203580). MSK1 activation by NMDA was transient, although ERK remained phosphorylated within the neuronal cytoplasm for several hours. Although BDNF increased ribosomal S6 kinase (RSK) phosphorylation, NMDA had no discernable effect on the phosphorylation of RSKs. Thus, phosphorylation and activation of MSK1 but not RSK could be an important step in the pathway linking NMDA-induced ERK phosphorylation to the activation of transcription factors required for the formation of long-term memory.

Regulation of myosin light chain phosphorylation by RhoB in neuronal cells

The phosphorylation of myosin light chain (MLC) is a key regulatory point in the control of cellular morphology. Evidence suggests that RhoA-a member of the Rho GTPase family-regulates MLC phosphorylation via Rho kinase (ROK). Neurones display subtle alterations in their cytoarchitecture during the synaptic plasticity following high-frequency stimulation. We have recently demonstrated that RhoB, and not RhoA, is activated in neurones by high-frequency stimulation. However, the downstream consequences of RhoB activation in cells are unclear. In this study, we tested the hypothesis that RhoB might stimulate neuronal MLC phosphorylation. Transfection of PC12 cells with constitutively active RhoB increased MLC phosphorylation. Conversely, dominant-negative RhoB vectors reduced MLC phosphorylation. The effect of RhoB was attenuated by pretreatment with a selective ROK inhibitor. This confirms that Rho GTPases are important regulators of MLC phosphorylation, but suggests that, in neuronal cells, the control is exerted via RhoB rather than RhoA.

cAMP controls human renin mRNA stability via specific RNA-binding proteins

It is now recognized that post-transcriptional mechanisms are pivotal to renin production. These involve factors that modulate renin mRNA stability. In 2003 new data has emerged from work in Australia and Germany that has identified several of the, as many as, 20 or so proteins involved. These include CP1 (hnRNP E1), HuR, HADHB, dynamin, nucleolin, YP-1, hnRNP K and MINT-homologous protein. Cyclic AMP (cAMP) is a crucial regulator of renin secretion as well as transcriptional and post-transcriptional control of expression. Many of the RNA-binding proteins that were identified responded to forskolin, increasing in amount by two to 10-fold. The cAMP mechanisms that regulate renin mRNA target, at least in large part, other genes that presumably encode some of these proteins. The increase in the expression of these then facilitates, sequentially, renin mRNA stabilization and destabilization. Our data, using a battery of different techniques, confirm that CP1 and HuR stabilize renin mRNA, whereas HADHB causes destabilization. These proteins target cis-acting C-rich sequences (in the case of CP1) and AU-rich sequences (HuR) in the distal region of the 3'-untranslated region of renin mRNA. We found HADHB was enriched in juxtaglomerular cells and that that within Calu-6 cells HADHB, HuR and CP1 all localized in nuclear subregions, as well as cytoplasm (HADHB and CP1) and mitochondria (HADHB) commensurate with the role each plays in control of renin mRNA stability. The specific proteins that bind to human renin mRNA have begun to be revealed. Cyclic AMP upregulates the binding of several of these proteins, which in turn affect renin mRNA stability and thus overall expression of renin.

Increased long-term potentiation in the CA1 region of rat hippocampus via modulation of GTPase signalling or inhibition of Rho kinase

There is accumulating evidence that Ras, and Ras-related GTPases of the Rho family, such as RhoA, RhoB and Rac1, are involved in synaptic plasticity in brain regions such as the hippocampus. We have recently shown that Rho family GTPases are activated by synaptic transmission in the CA1 region of the hippocampus. Since the function of these GTPases is dependent on post-translational isoprenylation by either farnesyl or geranylgeranyl transferases, we tested the hypothesis that inhibition of isoprenylation would modify long-term potentiation (LTP). Farnesyl transferase inhibition, which suppressed activation of RhoB and Ras but not RhoA or Rac1, reduced the magnitude of LTP, while geranylgeranyl transferase inhibition, which inhibited RhoA and Rac1 but not RhoB, increased the magnitude of LTP. In addition, Y-27632, a specific inhibitor of a downstream effector of Rho GTPases-Rho-kinase-also increased the magnitude of LTP. This provides strong evidence that GTPases are important mediators of synaptic plasticity, and demonstrates that Rho-kinase acts to reduce the degree of plasticity at hippocampal synapses during LTP. Rho-kinase inhibitors have the unusual property of increasing the magnitude of LTP, and so may be potential cognitive enhancers.

Differential regulation of MAP2 and αCamKII expression in hippocampal neurones by forskolin and calcium ionophore treatment

The genes encoding microtubule-associated protein 2 (MAP2), and the alpha subunit of calcium/calmodulin-dependent protein kinase II (alphaCaMKII), are members of a small number of genes whose expression is increased in hippocampal neurones during the intermediate phase of long-term potentiation (LTP)-a phase dependent on mRNA translation but not on gene transcription. However, the intracellular signalling pathways which mediate these increases in expression are largely unknown. Organotypic slice cultures of rat hippocampus were exposed to either forskolin (to elevate cAMP levels), A23187 (to increase intracellular Ca(2+) levels) or the corresponding vehicle. The levels of immunoreactive (ir-) MAP2 were increased 4 h after forskolin treatment, but were unaffected by A23187 treatment. Conversely, the levels of ir-alphaCaMKII were increased 4 h after A23187 treatment, but were unaffected by forskolin. The regulation of the expression of these proteins was the same in the CA3 region as in the CA1 and dentate gyrus of the hippocampus. While rapamycin reduced the basal levels of ir-MAP2, it did not affect the ability of either forskolin or A23187 to enhance ir-MAP2 or ir-alphaCaMKII levels. These results suggest that cAMP and Ca(2+) differentially modulate the expression of these two plasticity-related genes, and that translational enhancement via the mammalian target of rapamycin kinase is not involved in these effects.

Activation of Rho GTPases by synaptic transmission in the hippocampus

Ras-related GTPases of the Rho family, such as RhoA and RhoB, are well-characterised mediators of morphological change in peripheral tissues via their effects on the actin cytoskeleton. We tested the hypothesis that Rho family GTPases are involved in synaptic transmission in the CA1 region of the hippocampus. We show that GTPases are activated by synaptic transmission. RhoA and RhoB were activated by low frequency stimulation, while the induction of long-term potentiation (LTP) by high frequency stimulation was associated with specific activation of RhoB via NMDA receptor stimulation. This illustrates that these GTPases are potential mediators of synaptic transmission in the hippocampus, and raises the possibility that RhoB may play a role in plasticity at hippocampal synapses during LTP.

Association of EDNRA , but not WNK4 or FKBP1B , polymorphisms with essential hypertension

In a study of the genetic basis of essential hypertension (HT), we tested four variants in three candidate genes not previously investigated in HT. These encoded the endothelin receptor type A (EDNRA), which transduces most of the vasoconstrictive properties of endothelin-1, protein kinase lysine deficient 4 (WNK4) whose gene resides in a HT linkage region on chromosome 17, and FK506-binding protein 1B (FKBP1B), which can reduce blood pressure by increasing nitric oxide. The variants were: for EDNRA, a G-->A in the 5'-UTR and C-->T in exon 8; for WNK4, a tetranucleotide repeat in intron 10; and for FKBP1B, a T-->C in exon 4. Subjects were Anglo-Celtic white Australians and included 155 HTs with two HT parents and 245 normotensives (NTs) whose parents were both NT. For EDNRA, we found a weak association of the exon 8 variant with HT (p = 0.019) and association of the 5'-UTR variant with elevation in systolic and diastolic blood pressure (BP) (p = 0.038 and 0.0031, respectively). The WNK4 intron 10 variant and the FKP1B exon 4 variant showed no association with HT, but tracking with BP was seen for the latter (p = 0.015 and 0.0011 for systolic and diastolic BP, respectively). Our study thus suggests possible involvement of EDNRA in essential HT.

Striatal neurones show sustained recovery from severe hypoglycaemic insult

Glucose deprivation provides a reliable model to investigate cellular responses to metabolic dysfunction, and is reportedly associated with permanent cell death in many paradigms. Consistent with previous studies, primary cultures of rat striatal neurones exposed to 24-h hypoglycaemia showed dramatically decreased sodium 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) metabolism (used as a marker of cell viability) and increased TUNEL staining, suggesting widespread DNA damage typical of apoptotic cell death. Remarkably, restoration of normal glucose levels initiated a sustained recovery in XTT staining, along with a concomitant decrease in TUNEL staining, even after 24 h of hypoglycaemia, suggesting recovery of damaged neurones and repair of nicked DNA. No alterations in the levels of four DNA repair proteins could be detected during hypoglycaemia or recovery. A reduction in intracellular calcium concentration was seen in recovered cells. These data suggest that striatal cells do not die after extended periods of glucose deprivation, but survive in a form of suspended animation, with sufficient energy to maintain membrane potential.

Distribution of Rho family GTPases in the adult rat hippocampus and cerebellum

Small GTPases are monomeric guanine nucleotide binding proteins of 20-25 kDa mass. Rho GTPases belong to the Ras superfamily of small GTPases. The small GTPases of the Rho family have been shown to participate in the organisation of the actin cytoskeleton and signal transduction pathways leading to gene transcription. Recent evidence suggests that Rho family GTPases may play an important role in synaptic communication in the brain, and particularly in synatic plasticity. In this study the distribution of RhoA, RhoB, RhoG, Cdc42, and Rac1 was investigated in hippocampal and cerebellar tissue of adult rat brain using immunohistochemical techniques. Previous studies suggest that distribution of Rho family mRNA is uniform throughout these structures. Here we provide evidence for differences in expression of these proteins between different regions of the hippocampus, and between the molecular and granular layers in the cerebellum. These differences may prove important with regard to the physiological functions of Rho family GTPases.

Involvement of NMDA receptors and a p21Ras-like guanosine triphosphatase in the constitutive activation of nuclear factor-kappa-B in cortical neurons

The transcription factor nuclear factor-kappa-B (NF-kappaB) is now recognised as a key mediator of physiological and pathological plasticity in the central nervous system (CNS), and ionotropic glutamate receptor stimulation potently triggers NF-kappaB activation. This study was designed to identify the mechanisms responsible for the high basal levels of activated NF-kappaB present in neurons in the cerebral cortex. In cultured cortical neurons, the basal levels of activated NF-kappaB were reduced by the glutamate receptor antagonists MK801 and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), but were not affected by exposure to a mitogen-activated protein (MAP) kinase kinase (MEK) inhibitor, a p38 MAP kinase inhibitor or a cyclic guanosine monophosphate (cGMP)-dependent protein kinase inhibitor. However, activated NF-kappaB levels were reduced by a guanylate cyclase inhibitor, the Src-family tyrosine kinase inhibitor PP1, or the farnesyl transferase inhibitors manumycin and farnesyl transferase (Ftase) inhibitor 1. There was no additive effect when MK801 was applied together with manumycin. These results suggest that the basal levels of activated NF-kappaB in cortical neurons are maintained partially by synaptic activity involving N-methyl- D-aspartate (NMDA) and AMPA/kainate glutamate receptors, coupled to activation of an Src-family tyrosine kinase and a p21(Ras)-like guanosine triphosphatase (GTPase) in a cGMP-dependent manner. The results are intriguing in the light of the recent identification of a synaptic p21(Ras) activator stimulated by cGMP.

Induction of differential patterns of local cerebral glucose metabolism and immediate-early genes by acute clozapine and haloperidol

Atypical antipsychotic drugs, such as clozapine, show many differences in their actions as compared to typical antipsychotic drugs, such as haloperidol. In particular, the neuroanatomical substrates responsible for the superior therapeutic profile of clozapine are unknown. In order to identify regions of the CNS which are affected either differentially or in parallel by clozapine and haloperidol, we have used 2-deoxyglucose autoradiography to monitor local cerebral glucose utilisation (LCGU), in parallel with in situ hybridisation to monitor the expression of five immediate-early genes (c-fos, fos B, fra 1, fra 2 and zif 268). Clozapine (20 mg/kg i.p.) caused a reduction in LCGU in many areas of the psychosis-related corticolimbothalamic and Papez circuits, such as the anterior cingulate and retrosplenial cortices and the mammillary body. Haloperidol (1 mg/kg i.p.) showed less ability to modulate LCGU in these regions. Clozapine also increased immediate-early gene expression in these limbic circuits, although the pattern of induction was different for each gene, and also differed from the pattern of effects on LCGU. The only region which displayed similar effects with both antipsychotics was the anteroventral thalamus, with LCGU and c-fos mRNA expression being altered similarly by both drugs. This further supports the hypothesis of the thalamus being a common site of antipsychotic action. Since the Papez circuit has been implicated in emotive learning, and to be involved in mediating the negative symptoms associated with schizophrenia, the greater action of clozapine on regions within this circuit may also provide clues to the atypical antipsychotic's superior efficacy against negative symptoms. This is one of the first studies which provides a direct comparison of regional activity as assessed by LCGU and by a panel of IEGs. The results emphasise the necessity of monitoring a number of different parameters of regional activity in order to identity the neuroanatomical substrate for actions of a drug in the CNS.

Association of beta2-adrenoceptor Gln27Glu variant with body weight but not hypertension

Beta2-adrenoceptor (beta2-ADR)-mediated vasodilatation decreases vascular reactivity and blood pressure (BP) and chromosome 5 where its gene (ADRB2R) resides and shows linkage to hypertension (HT). A Gln27Glu ADRB2R variant confers resistance to agonist-induced desensitization and enhanced vasodilator response to isoprenaline. Therefore, we carried out a case-control study in a cohort of HT and normotensive (NT) Anglo-Celtic Australian white subjects whose parents had a similar BP status as the subjects. Glu27 frequency was 0.41 in 108 HT and 0.42 in 141 NT (chi2 = 0.05, P = .82). Within the HT group, the Glu27 allele was more prevalent in 61 subjects who were overweight (body mass index [BMI] > or = 25 kg/m2) compared with 41 who were lean (BMI <25 kg/m2); ie, 0.49 v 0.31, respectively (chi2 = 6.4, P = .012). Furthermore, Glu27 tracked with elevation in BMI in these subjects: 24 +/- 4 kg/m2, 27 +/- 5 kg/m2, and 28 +/- 5 kg/m2 for Gln/Gln, Gln/Glu, and Glu/Glu, respectively (P = .0058 by one-way ANOVA). Thus, the Gln27Glu beta2-ADR variant is excluded in HT, but might influence body weight.

Renin gene expression: the switch and the fingers

1. Now that many of the factors and control elements that regulate renin transcription have been identified, the scene is set to address the question of the mode of control. 2. Based on current gene control theories, either renin gene transcription in each cell undergoes gradual responses over a continuous range or transcription is switched completely on or completely off. The latter model of 'binary' or 'variegated' expression fits with observations such as the 'recruitment' of new cells for renin expression during strong physiological stimulation and the progressive switching off of expression during development. 3. The renin gene offers an excellent general model for testing the mode of control of genes that are subject to continuous modulatory influences from the demands of physiological perturbations. This is because the promoter is well characterized and is subject to the influence of a strong far-upstream enhancer, one of the key elements of the variegation model. 4. Renin is also controlled at the post-transcriptional level and this, like transcriptional control, involves cAMP mechanisms. We have cloned the human and mouse homologues of a protein (ZNF265) that is important in renin mRNA processing and stability. This uses 'zinc fingers' to bind the mRNA. The role of this and other proteins in splicing and stabilization of mRNA is now being elucidated. 5. Unravelling the mechanisms that determine rate of supply of renin mRNA to the biosynthetic machinery is being assisted by advances in concepts and techniques in the rapidly moving field of genomics.

Characterization of nucleoside and DNA adducts formed by S-(1-acetoxymethyl)glutathione and implications for dihalomethane-glutathione conjugates

S-(1-Acetoxymethyl)glutathione (GSCH(2)OAc) was synthesized and used as a model for the reaction of glutathione (GSH)-dihaloalkane conjugates with nucleosides and DNA. Previously, S-[1-(N(2)-deoxyguanosinyl)methyl]GSH had been identified as the major adduct formed in the reaction of GSCH(2)OAc with deoxyguanosine. GSCH(2)OAc was incubated with the three remaining deoxyribonucleosides to identify other possible adducts. Adducts to all three nucleosides were found using electrospray ionization mass spectrometry (ESI MS). The adduct of GSCH(2)OAc and deoxyadenosine was formed in yield of up to 0.05% and was identified as S-[1-(N(7)-deoxyadenosinyl)methyl]GSH. The pyrimidine deoxyribonucleoside adducts were formed more efficiently, resulting in yields of 1 and 2% for the GSCH(2)OAc adducts derived from thymidine and deoxycytidine, respectively, but their lability prevented their structural identification by (1)H NMR. On the basis of the available UV spectra, we propose the structures S-[1-(N(3)-thymidinyl)methyl]GSH and S-[1-(N(4)-deoxycytidinyl)methyl]GSH. Because adduct degradation occurred most rapidly at alkaline and neutral pH values, an enzymatic DNA digestion procedure was developed for the rapid hydrolysis of DNA to deoxyribonucleosides at acidic pH. DNA digests were completed in less than 2 h with a two-step method, which consisted of a 15 min incubation of DNA with high concentrations of deoxyribonuclease II and phosphodiesterase II at pH 4.5, followed by incubation of resulting nucleotides with acid phosphatase. Analysis of the hydrolysis products by HPLC-ESI-MS indicated the presence of the thymidine adduct.

ZNF265--a novel spliceosomal protein able to induce alternative splicing

The formation of the active spliceosome, its recruitment to active areas of transcription, and its role in pre-mRNA splicing depends on the association of a number of multifunctional serine/arginine-rich (SR) proteins. ZNF265 is an arginine/serine-rich (RS) domain containing zinc finger protein with conserved pre-mRNA splicing protein motifs. Here we show that ZNF265 immunoprecipitates from splicing extracts in association with mRNA, and that it is able to alter splicing patterns of Tra2-beta1 transcripts in a dose-dependent manner in HEK 293 cells. Yeast two-hybrid analysis and immunoprecipitation indicated interaction of ZNF265 with the essential splicing factor proteins U1-70K and U2AF(35). Confocal microscopy demonstrated colocalization of ZNF265 with the motor neuron gene product SMN, the snRNP protein U1-70K, the SR protein SC35, and with the transcriptosomal components p300 and YY1. Transfection of HT-1080 cells with ZNF265-EGFP fusion constructs showed that nuclear localization of ZNF265 required the RS domain. Alignment with other RS domain-containing proteins revealed a high degree of SR dipeptide conservation. These data show that ZNF265 functions as a novel component of the mRNA processing machinery.

G-protein beta3 subunit gene splice variant in obesity and overweight

OBJECTIVE

To determine whether the C825T polymorphism of the G-protein beta3 subunit gene (GNB3) is associated with overweight and obesity. This polymorphism leads to a splice variant (Gbeta3-s) with higher activity and very strong association with essential hypertension.

DESIGN

A cross-sectional case-control study.

SUBJECTS

The sets of affected and control British/European Caucasian subjects used were: (i) an obesity clinic group most of whom had "morbid obesity" (mean body mass index (BMI) for group=43+/-8 kg/m(2)) and non-obese controls (BMI< or =30); (ii) a group of overweight/obese healthy normotensive community volunteers (BMI>25; mean 29+/-5) and controls (BMI< or =25; mean 23+/-1); (iii) a group of overweight/obese hypertensive patients (BMI>25; mean 30+/-4) and lean hypertensive controls (BMI< or =25; mean=23+/-2).

MEASUREMENTS

BMI, blood pressure, serum lipids, alleles of GNB3 polymorphism.

RESULTS

Compared with control, frequency of the T allele in obese subjects was higher by 12% in (i), 17% in (ii) and 28% in (iii), but the differences were not statistically significant. Slight tracking of the T allele with elevation in BMI was, however, observed, in the obesity clinic group (P=0.018).

CONCLUSION

The C825T splice variant of GNB3 makes little if any contribution to obesity in the groups we tested.

Influence of an inducible nitric oxide synthase promoter variant on clinical variables in patients with coronary artery disease

Pathophysiological processes in coronary artery disease (CAD) are influenced by genetic factors. Since (i) inducible nitric oxide synthase (iNOS) has important cardiovascular effects, and (ii) the promoter of the iNOS gene (NOS2A) is genetically modulated by a 4 bp insertion/deletion (+/-) polymorphism located 0.7 kb upstream, we decided to examine the influence of this variant on clinical variables in 856 CAD patients of Anglo-Celtic/Northern European extraction. We found that 2% of CAD patients were homozygous for the + allele, and 19% were heterozygous. Males made up 74% of the patient group, and in these the + allele was associated with 38% higher plasma glucose levels (P=0.005), a 4.8% elevation in the waist/hip ratio (P=0.009) and a 48% greater frequency of unstable angina (P=0.014). The + allele, by influencing iNOS expression, could thus contribute to indices of insulin resistance and angina severity in male CAD patients.

Activation of p44/p42 MAP kinase in striatal neurons via kainate receptors and PI3 kinase

The members of the mitogen-activated protein (MAP) kinase family -- p44/p42 MAP kinase (ERK), c-jun N-terminal kinase (JNK) and p38 MAP kinase (p38) are known to be important mediators of the physiological plasticity or neurotoxicity induced in the striatum by activation of ionotropic glutamate receptors. However, our knowledge of the class of glutamate receptor and the intracellular pathways involved derives totally from studies on embryonic neurons, where the mechanisms are likely to be totally different from those operating in mature neurons. In superfused striatal slices from adult rats, NMDA and kainate, but not AMPA, were found to activate ERK. No activation of p38 or JNK was detected following treatment with any ionotropic glutamate receptor agonist. The activation of ERK by kainate was blocked by the ERK kinase (MEK) inhibitor PD98059, and the PI3 kinase inhibitor wortmannin, but not by the p38 MAP kinase inhibitor SB203580. This provides evidence for a novel pathway linking striatal kainate receptors to ERK activation via PI3 kinase and MEK.

TNFRSF1B in genetic predisposition to clinical neuropathy and effect on HDL cholesterol and glycosylated hemoglobin in type 2 diabetes

OBJECTIVE

Genetic variation in the tumor necrosis factor (TNF) receptor 2 gene (TNFRSF1B) has shown association with insulin resistance in type 2 diabetes, hypercholesterolemia, coronary artery disease, and essential hypertension. Here we tested the TNFRSF1B marker used in the latter studies in type 2 diabetes patients.

RESEARCH DESIGN AND METHODS

A case-control study of a microsatellite marker with five alleles (CA13- CA17) in intron 4 of TNFRSF1B was performed in 357 well-characterized white patients and 183 healthy control subjects.

RESULTS

The CA16 allele was associated with clinical neuropathy (frequency = 27% in 69 patients with the condition versus 16% in 230 subjects without the condition; chi2 = 9.0, P = 0.011; odds ratio = 2.1 [95% CI 1.2-3.8]). No association was seen with other complications or diabetes itself. The CA16 allele tracked with elevation plasma HDL cholesterol (1.3 +/- 0.2, 1.2 +/- 0.4, and 1.1 +/- 0.2 for CA16/CA16, CA16/-, and -/-, respectively; n = 9, 110, and 218, respectively; P = 0.009) and reduction in plasma glycosylated hemoglobin (6.6 +/- 0.3, 8.3 +/- 0.2, and 8.1 +/- 0.1 for CA16/CA16, CA16/-, and -/-, respectively; n = 9, 102, 205, respectively; P = 0.007) Significance remained after Bonferroni correction for multiple testing.

CONCLUSIONS

Genetic variation in or near TNFRSF1B may predispose clinical neuropathy, reduced glycosylated hemoglobin, and increased HDL cholesterol in type 2 diabetes patients. The latter could be part of a protective response.

Decreased renal expression of nitric oxide synthase isoforms in adrenocorticotropin-induced and corticosterone-induced hypertension

Administration of adrenocorticotropic hormone (ACTH) leads to the development of hypertension. Because glucocorticoids can affect the nitric oxide system at several sites, the present study tested the hypothesis that nitric oxide synthase (NOS) expression may be altered in ACTH-induced and corticosterone-induced hypertension in the rat. This was addressed by measuring Nos1, Nos2, and Nos3 mRNA in the kidney, adrenal gland, heart, and hypothalamus of 16 ACTH-treated and 16 vehicle-treated rats as well as in 10 corticosterone-treated and 10 control rats. In addition, in situ hybridization and immunohistochemistry were used to confirm changes by detection of Nos in RNA and NOS protein in tissues. Systolic blood pressure of ACTH and corticosterone rats was elevated (165+/-6 and 162+/-11 mm Hg; P<0.001 versus control). Each Nos isoform mRNA was measured by reverse transcriptase-polymerase chain reaction technique. In ACTH rats, mRNA for Nos2 was reduced in renal cortex by 58+/-5% and in medulla by 68+/-7%; for Nos3, mRNA reductions of 59+/-6% and 51+/-11% were seen (P<0.001 after Hochberg correction for multiple comparisons). In corticosterone rats, Nos2 mRNA decreased in cortex by 68+/-5% and in medulla by 62+/-6%; Nos3 mRNA by 50+/-8% in cortex, and Nos1 by 29+/-7% in medulla (all P<0.001 after Hochberg correction). Reductions seen in kidney were supported by in situ hybridization and immunohistochemistry. Apart from a 62+/-2% decrease in Nos2 mRNA in adrenal of ACTH rats (corrected P<0.05), no significant changes were seen in the other nonrenal tissues for any isoform. In conclusion, we have shown for the first time that the physiological components of glucocorticoid action (ACTH and corticosterone) when given chronically in vivo reduce Nos2 and Nos3 expression in the kidney. Such changes are consistent with a role in hypertension for ACTH and corticosterone.

Tumor necrosis factor receptor 2 gene (TNFRSF1B) in genetic basis of coronary artery disease

Tumor necrosis factor (TNF)-alpha has been implicated in pathophysiological processes in coronary artery disease (CAD). TNF receptor 2 is of particular interest in mediating such effects. The gene for this receptor (TNF-RSF1B) has, moreover, been implicated in hypertension, elevated cholesterol and insulin resistance. TNFRSF1B is thus a worthy candidate in studies of the genetic basis of CAD. We therefore conducted a case-control study of a microsatellite marker with five alleles (CA13-CA17) in intron 4 of TNFRSF1B in 1006 well-characterized white patients with angiographically confirmed CAD and a control group of 183 healthy subjects. We found a strong association of the TNFRSF1B marker with CAD (chi2=40, P=0.00000069). The frequency of the CA16 allele was 33% in CAD vs. 21% in control (odds ratio, OR, to have CAD for presence vs. absence of CA16 allele in CA16 homozygotes was 4.5, 95% CI 2.1-9.4, P<0.0001; in CA16 heterozygotes OR was 1.3, 95% CI 0.94-1.89, P=0.10). The frequency of the major allele (CA15) was 43% in CAD vs. 56% in controls (in CA15 homozygotes OR 0.33, 95% CI 0.20-0.52, P<0.0001; in heterozygotes OR 0.41, 95% CI 0.26-0.63, P<0.0001). In a stepwise logistic regression model the CA16 allele was significantly associated with overweight (OR 1.44, 95% CI 1.0-1.9, P=0.027). Apolipoprotein A-I was elevated (P<0.0001), as was high-density lipoprotein (P=0.098), and severity of angina was decreased (P=0.024) as a function of genotype. Plasma soluble (s) TNF-R2 was 5.1 +/- 0.1 ng/ml in CAD vs. 3.2 +/- 0.1 in control (P<0.0001), 5.2 +/- 0.1 in the presence vs. 4.6 +/- 0.2 in the absence of vessel disease (P=0.009), and rose with increasing severity of angina: 4.2 +/- 0.2 (no angina), 5.0 +/- 0.1 (stable angina), 5.4 +/- 0.2 (unstable angina; P=0.003). sTNF-R2 was correlated with age, cholesterol, creatinine, fibrinogen, transforming growth factor beta and homocysteine and was influenced by TNFRSF1B genotype. Thus genetic variation in or near the TNFRSF1B locus may predispose to CAD.

Capacity for purinergic control of renin promoter via P2Y(11) receptor and cAMP pathways

Renin secretion can be stimulated by ATP via purinergic P2Y receptors. ATP is a cotransmitter with norepinephrine and is released from the cytosol during cell damage. Such release could account for the de novo renin expression seen in the proximal tubule in renal disease and in myocardial infarct borders. Whereas most P2Y purinoceptor subtypes utilize phosphoinositide signal-transduction pathways, the effector mechanisms of the subtype P2Y(11) also involve increases in cAMP, a well-known renin secretagogue and stimulus to renin production. The present study tested the effect of ATP on human renin gene (REN) promoter activity and the role of P2Y(11). By means of reverse transcriptase-polymerase chain reaction, we found that renin-expressing Calu-6 cells express P2Y(11) mRNA. Expression was also detected in the brain, kidney, testis, muscle, liver, and spleen. We made a novel cell line (Calu-6/P2Y11) in which P2Y(11) cDNA, under the control of a strong promoter, was stably integrated into genomic DNA. These cells produced P2Y(11) mRNA during culture. Treatment of Calu-6/P2Y11 cells with 1 mmol/L ATP caused a 3-fold increase in renin mRNA and protein over 36 hours. Transient transfection of Calu-6/P2Y11 cells with constructs containing 896 bp of human REN 5'-flanking DNA linked to the luciferase reporter gene led to a 5.8+/-0.6-fold increase (mean+/-SEM) in reporter activity in response to ATP (P=0.0015). In contrast, UTP produced only a 1.4+/-0.1-fold increase (P=0.016). For ADP, it was 1.7+/-0.1-fold (P=0.011). The response profile was ATP>ADP>AMP=adenosine=0, consistent with a P2Y(11) effect. Mutation of the cAMP response element (CRE) located at -222 in the REN promoter DNA abolished the effect of ATP. Furthermore, ATP induced a rapid, time-dependent increase in the phosphorylation of CRE binding protein (CREB) and activating transcription factor-1. These data implicate a cAMP pathway in mediation of the P2Y(11) effect. In conclusion, we have made a novel cell line that overexpresses the P2Y(11) purinoceptor. Stimulation of these cells by ATP activates a cAMP signal-transduction pathway that phosphorylates CREB and stimulates renin promoter activity via the CRE at -222. The data raise the possibility of a contribution of ATP/P2Y(11) effects to sympathetic stimulation of renin, as well as to responses in renin seen after tissue damage, such as in kidney disease and myocardial infarction.

Association analyses of endothelial nitric oxide synthase gene polymorphisms in essential hypertension

Endothelial nitric oxide synthase (eNOS), encoded by NOS3, is a potent regulator of vasomotor tone and peripheral resistance. Congenic experiments indicate that a chromosomal segment containing the rat eNOS gene contributes to rat spontaneous hypertension (HT). A role for NOS3 in onset of essential hypertension (HT) is, however, controversial. We therefore decided to test NOS3 polymorphisms in a set of patients who have an accentuated ability to show an existing genetic association. The 112 HT subjects had two HT parents and the normotensive (NT) subjects had two NT parents. All were Anglo-Celtic whites. The two most promising polymorphisms, viz, a biallelic variable number of tandem repeats (VNTR) in intron 4 and an exon 7 variant that leads to an amino acid change (Glu298Asp), were genotyped by PCR (and BanII digestion in the case of the latter). Frequency of the minor allele of the VNTR was 0.11 in the NT and 0.10 in the HT subjects (P = .9). For the exon 7 variant, Asp298 frequency was 0.30 and 0.32 in each respective group (P = .6). Tracking was seen for the Asp298 allele with elevation in body mass index (P = .034), and the minor allele of the VNTR with elevation in LDL (P = .007) and reduction in HDL (P = .048). In conclusion, we saw no association of NOS3 markers with HT in the population studied. However, possible genotypic effects on plasma lipids and body mass index might warrant further studies, especially in view of possible associations with heart disease.