Taking a chance on outcome standardisation: A cross-sectional analysis assessing the uptake of the prevention of preterm birth core outcome set in randomised controlled trials

OBJECTIVE

Analyse uptake of the core outcome set (COS) within preterm birth (PTB) clinical trials.

DESIGN

On 26 June 2023, we conducted a systematic search of phase III/IV trial registry entries regarding PTB interventions via ClinicalTrials.gov and the International Clinical Trial Registry Platform. These trials were analysed for the outcomes measured.

SETTING

N/A.

SAMPLE

After searching the two databases, 5257 randomised controlled trials (RCTs) were screened, resulting in 92 RCTs for analysis.

METHODS

Inclusion criteria were the following: subjects were patients receiving an intervention for PTB, study enrolment began within 5 years prior to publication of PTB COS to 26 June 2023, and evaluated the efficacy of interventions. Authors screened and extracted data in masked, duplicate fashion, then performed an interrupted time series analysis, analysis of variance and correlation analysis.

MAIN OUTCOME MEASURES

We extracted outcomes measured by each clinical trial in our sample. Trials were analysed for the percentage of adopted outcomes from PTB COS.

RESULTS

After COS publication, there was no significant change in percentage of COS outcomes measured. The most measured outcome was 'offspring mortality' (54.34%, 50/92) and the least measured outcome was 'late neonatal neurodevelopment morbidity' (3.26%, 3/92). Additionally, 22.83% (21/92) of trials measured zero outcomes related to the PTB COS.

CONCLUSION

Our results demonstrated no significant change in outcome measurement before or after PTB COS publication. We recommend focusing on both the measurement of outcomes and the assessments that are used.

Assessing the degree to which randomized control trials align with the core outcome set for osteoarthritis of knee and hip: A cross-sectional analysis

OBJECTIVE

To assess the degree of core outcome set alignment and identify issues with alignment to the 2019 COS among clinical trial registrations focused on knee and/or hip osteoarthritis (OA).

METHODS

Our search was performed on registered knee and hip OA randomized controlled trials (RCTs) available on ClinicalTrials.gov and WHO International Clinical Trials Registry Platform. The screening process considered trials registered between 8/2014 and 6/2023. We extracted data on general trial characteristics and the five trial endpoints detailed in the COS (pain, physical function, quality of life, patient global assessment, and adverse events), in a masked and duplicate manner. The frequencies of COS alignment were assessed over time prior to and after COS publication.

RESULTS

Of the 10,718 RCTs screened, 481 met inclusion criteria. Most were phase 3 (368/481, 76.51%) and heavily university-funded (184/481, 38.25%). Despite the 2019 COS, no marked enhancement in overall alignment was noted. The outcome 'Pain' exhibited the highest degree of COS alignment (455/481, 94.59%), whereas 'adverse events' lagged behind (89/481, 18.50%). Additionally, trial factors such as 'Continent', 'Funding Type', and 'Recruitment Status' displayed no significant influence on COS alignment.

CONCLUSIONS

Despite the acknowledged advantages of using COS in RCTs and the availability of an updated COS, the alignment to these outcomes remains notably low. Significant efforts are needed to encourage broader adoption in future studies on knee and hip OA, with the aim of improving research quality and patient care.

Assessing uptake of the core outcome set in clinical trials for immune thrombocytopenia: A cross-sectional analysis

INTRODUCTION

Clinical trials (CTs) guide clinical practice, but inconsistent outcome reporting presents challenges. To increase comparability, a core outcome set (COS) was created for primary Immune thrombocytopenia (ITP) in 2009 to standardize outcome measurements. We aimed to evaluate uptake of the primary ITP COS in CT registries.

MATERIALS & METHODS

Our cross-sectional analysis employed a search string on ClinicalTrials.gov and ICTRP for phase III/IV CTs in June 2023. Inclusion criteria consisted of subjects with primary ITP, study was registered five years before COS publication to June 26, 2023, and assessed effectiveness of interventions. Two investigators extracted data in a masked, duplicate manner. Interrupted time series analysis, ANOVAs, and correlation analyses were conducted to assess the main outcome of COS uptake pre/post COS publication.

RESULTS

The search identified 131 eligible trials for data extraction. Altogether, 38.2 % (50/131) followed IWG platelet response guidelines. An alternative platelet count measurement was 50,000 × 109 L, with 46.56 % (61/131) of trials reporting it. The most measured outcome was adverse events (106/131, 80.9 %). Remaining secondary outcomes were measured in <50 % of studies. After COS publication, there was a statistically non-significant 0.03 % (p = 0.50, CI 95 % = [-0.06, 0.13]) 0.03 % (p = 0.50, CI 95 % = [-0.06, 0.13]) increase in the monthly trend of COS-defined outcomes.

CONCLUSION

We found a non-significant increase in uptake of the ITP COS since its publication and highlighted the lack of standardization among endpoints within ITP clinical trials. Our analysis highlights the need for heightened awareness and a COS update that acknowledges the variability in clinical trials.

Reporting of Harms in Randomized Controlled Trials Published in Urology Journals: An Updated Analysis

PURPOSE

Harms are often overlooked, but important, outcomes of randomized controlled trial reporting. Our goal was to determine if harms reporting has improved in high-impact urology journals.

MATERIALS AND METHODS

Randomized controlled trials published in The Journal of Urology®, Urology, European Urology, and BJU International in 2012 and 2020 were analyzed. Each randomized controlled trial was evaluated by 2 authors in a masked-duplicate fashion to evaluate for adherence to harms reporting guidelines recommended by the Consolidated Standards of Reporting Trials (CONSORT) group.

RESULTS

One hundred and thirty-two published studies met inclusion criteria. Between 2012 and 2020, there was a statistically significant increase in the median number of harms criteria reported between 2012 and 2020 (5.3 vs 7.2; P = .01). Methods criteria demonstrating the greatest improvements included item #3 "which harms were assessed," item #4a "when harm information was collected," and item #4b "methods to attribute harm to intervention." Results sections with the most improvement in reporting include item #6 "reasons for patient withdrawal," item #8a "effect size for harms," and item #8b "stratified serious + minor harms."

CONCLUSIONS

Reporting of adverse events in randomized trials published in several top urology journals has demonstrated marked improvement. Studies published in 2020 reported approximately 70% of CONSORT-Harms criteria-an increase of nearly 40% since 2004. While these improvements mark significant change, deficits remain present and should be addressed to provide clinicians with the most complete perspective possible.

Assessing the uptake of the type 1 diabetes core outcome set in randomized controlled trials: A Cross-Sectional study

AIMS

This study analyzed uptake of the core outcome set (COS) for type 1 diabetes (T1D) and trends in its use before and after its development in December 2017.

METHODS

On June 26, 2023, ClinicalTrials.gov was systematically searched for T1D randomized controlled trials. The Core Outcome Measures in Effectiveness Trials (COMET) database provided a COS of eight key outcomes for analysis. Included trials were analyzed for COS uptake before and after its release in December 2017 in a masked, duplicate fashion by independent reviewers. We also calculated the proportion of trials that measured the complete COS and assessed the most frequently reported COS outcomes.

RESULTS

Of 3,792 originally screened articles, 144 RCTs were included in the final sample. Following COS publication, its use steadily decreased. Within the COS, HbA1c and severe hypoglycemia were most frequently implemented as endpoints; other recommended outcomes were rarely used in the published trials.

CONCLUSION

Despite the 2017 T1D COS publication, use has decreased over time. This inconsistency negatively influences evidence-based practices and care. Educating researchers on COS and promoting uptake is crucial. Wider COS adoption in T1D trials could enhance clinical research overall. Further study of barriers and facilitators influencing uptake is essential to support consistent use and reporting.

Assessing uptake of the core outcome set in randomized controlled trials for Parkinson's disease: A systematic review

BACKGROUND

Parkinson's Disease (PD) affects more than 10 million individuals, with increasing incidence worldwide. As PD's incidence rises, research funding is increasing substantially. PD's core outcome set (COS) provides standardization for PD clinical trial outcomes, improves research quality, and study comparability. Our study aimed to analyze COS uptake rate before and after the PD COS publication.

METHODS

We searched ClinicalTrials.gov to retrieve phase III/IV adult PD trials published between 2013 and 2023. Screening for inclusion and data extraction occurred in a masked, duplicate fashion. Trial characteristics and COS uptake rate were extracted from this sample.

RESULTS

In our 111 included trials, the COS uptake rate was highest for the 'Walking and Balance' outcome and lowest for the 'Hospital Admissions' outcome. Overall, there was a non-significant monthly increase of 0.26 % (P = 0.266, CI = [-0.20, 0.72]) in "COS-defined outcome" measurement when comparing pre- and post-COS publication.

CONCLUSION

Our study found no significant increase in COS uptake in PD clinical trials. We found multiple outcomes to be vastly unmeasured and heterogeneity among the measurement instruments used. These findings complicate standardizing and comparing RCT outcomes. Overcoming these barriers is vital to improving the usefulness of PD research.

Inequities in the treatment of opioid use disorder: A scoping review

BACKGROUND

Given the lack of access to evidenced-based OUD treatment and the corresponding overdose crisis, researchers must evaluate and report health care inequities involving the treatment of OUD. Additionally, clinicians should be aware of these inequities in the treatment of patients.

METHODS

We carried out a scoping review of the literature regarding health inequities in treatment for OUD in July 2022. The study team retrieved articles published between 2016 and 2021 from MEDLINE and Ovid Embase. After authors received training, screening and data extraction were performed in masked, duplicate fashion. The team screened a total of 3673 titles and abstracts, followed by 172 articles for full-text review. The inequities that we examined were race/ethnicity, sex or gender, income, under-resourced/rural, occupational status, education level, and LGBTQ+. We used Stata 17.0 (StataCorp, LLC, College Station, TX) to summarize data and statistics of the studies within our sample.

RESULTS

A total of 44 studies evaluating inequities in OUD treatment met inclusion criteria. The most common inequity that studies examined was race/ethnicity (34/44 [77.27 %] studies), followed by under-resourced/rural (19/44 [43.18 %] studies), and sex or gender (18/44 [40.91 %] studies). LGBTQ+ (0/44 [0.0 %] studies) was not reported in the included studies. Our results indicate that many historically marginalized populations experience inequities related to access and outcomes in OUD treatment. The included studies in our scoping review occasionally demonstrated inconsistent findings.

CONCLUSIONS

Gaps exist within the literature on health inequities in treatment for OUD. The most examined inequities were race/ethnicity, under-resourced/rural and sex or gender, while studies did not examine LGBTQ+ status. Future research should aim to advance and supplement literature investigating health inequities in OUD treatment to ensure inclusive, patient-centered care.

An analysis of harms reporting in systematic reviews regarding ketorolac for management of perioperative pain

BACKGROUND

Owing to the frequent perioperative use of ketorolac tromethamine and its ability to minimise postoperative opioid requirements, it is important to continually reassess harms associated with its use. Our primary objective was to investigate the extent of harms reporting in systematic reviews (SRs) on ketorolac for perioperative pain.

METHODS

In May 2022, we conducted a search of major databases, MEDLINE (PubMed and Ovid), Embase, Epistemonikos, and the Cochrane Database of Systematic Reviews to identify eligible SRs on ketorolac for perioperative pain. Screening and data extraction were performed in masked, duplicate fashion. A MeaSurement Tool to Assess systematic Reviews-2 (AMSTAR-2) was used to appraise the methodological quality of included SRs. Corrected covered area (CCA) was calculated to determine overlap of primary studies between SR dyads.

RESULTS

A total of 28 SRs evaluating 630 primary studies met the inclusion criteria. Seven SRs (7/28, 25%) reported no harms and 17 SRs (17/28, 60.7%) reported ≤50% of harms items. A significant association was found between completeness of harms reporting and whether harms were specified as a primary outcome (P<0.001). No other associations were statistically significant. Regarding methodological quality, 22 SRs were appraised as 'critically low' (22/28, 78.6%), 5 as 'low' (5/28, 17.9%), and 1 as 'high' (1/28, 3.6%). One SR dyad had a CCA >50% but neither reported harms.

CONCLUSIONS

The extent of harms reporting in systematic reviews was inadequate. Given the importance that systematic reviews have on guiding perioperative decision-making, it is essential to improve the completeness of harms reporting.

Comparison of 3.0-T MR vs 3.0-T MR arthrography of the hip for detection of acetabular labral tears and chondral defects in the same patient population

OBJECTIVE

We report our experience in diagnostic sensitivity of 3.0-T conventional MR vs 3.0-T MR arthrography of the hip for detection of acetabular labral tears and chondral defects in the same patient population.

METHODS

43 consecutive patients had both conventional hip MR and MR arthrography examinations performed. These examinations were reviewed retrospectively by independent reading of two musculoskeletal radiologists who read the MR and MR arthrogram examinations in a randomized fashion (i.e. MR and MR arthrogram examinations were read at separate sittings and in a randomized fashion so as not to bias reviewers). Scans were assessed for acetabular labral tears and chondral defects. All patients went on to arthroscopy.

RESULTS

Of these 43 patients, 40 had acetabular labral tears read by Reader 1 and 39 had acetabular labral tears read by Reader 2 on MR arthrogram, 39 had acetabular labral tears read by Reader 1 and 38 had acetabular labral tears read by Reader 2 on conventional MR examination. There were 42 labral tears in 43 patients at arthroscopy. There were four false-negative labral tears compared with arthroscopy on MR and three false negatives on MR arthrography for Reader 1 and five false negatives on MR and four false negatives on MR arthrography for Reader 2. Each reader had one false-positive labral tear compared with arthroscopy on both MR and MR arthrography. There were 32 acetabular chondral defects at arthroscopy. Reader 1 saw 21 acetabular chondral defects on conventional MR and 27 chondral defects at MR arthrography. Reader 2 saw 19 acetabular chondral defects at conventional MR and 25 acetabular chondral defects on MR arthrography. There were no false-positive readings of chondral defects compared with arthroscopy on MR and one false positive for Reader 1 and two false positives for Reader 2 on MR arthrography as compared with arthroscopy. On conventional MR examination, sensitivities and specificities as compared with arthroscopy were as follows: Reader 1 acetabular labral tear (90% sensitivity, 0% specificity) and Reader 2 acetabular labral tear (88% sensitivity, 0% sensitivity). On MR arthrogram, sensitivities and specificities as compared with arthroscopy for Reader 1 were 93%, 0% and for Reader 2 were 90%, 0%, respectively. Sensitivities and specificities for detection of acetabular chondral defects as compared with arthroscopy were Reader 1 conventional MR (65% sensitivity, 100% specificity), Reader 1 MR arthrography (81% sensitivity, 91% specificity), Reader 2 conventional MR (59% sensitivity, 100% specificity) and Reader 2 MR arthrography (71% sensitivity, 82% specificity).

CONCLUSION

In this series, 3.0-T MR demonstrated sensitivity for detection of acetabular labral tears that rivals the sensitivity of 3.0-T MR arthrography of the hip. In this series, 3.0-T MR arthrography was more sensitive than conventional 3.0-T MR for detection of acetabular chondral defects.

ADVANCES IN KNOWLEDGE

3.0-T MR and MR arthrography are near equivalent in the diagnosis of acetabular labral tears. This information is useful for pre-operative planning.

How often do surgeons intervene on shoulder labral lesions detected at MR examination? A retrospective review of MR examinations correlated with arthroscopy

OBJECTIVE

We report the prevalence of surgical intervention on shoulder labral lesions detected at MR examinations and how surgeons describe labral tears seen at MR examinations in their arthroscopy reports.

METHODS

A retrospective review of 100 consecutive patients aged 50 years or younger who had shoulder labral tears on MR and went on to have surgery performed. It was determined whether surgical intervention was performed on the MR lesions.

RESULTS

Of these 100 patients, 72 had superior labral anterior to posterior (SLAP) tears, 38 had posterior labral tears and 28 had anterior labral tears on MR examination. All 100 patients went on to arthroscopy. All lesions described on MRI were described on arthroscopy. Of the 72 SLAP tears, 64 were described as fraying on arthroscopy with 51 debrided. The remaining eight SLAP tears were tacked surgically. Of the 38 posterior labral tears, 36 were described as fraying on arthroscopy with 29 debrided and 2 had surgical tacking performed. Of the 28 anterior labral tears described on MR examination, 26 had surgical tacking performed and 2 were debrided. There were four SLAP tears, two anterior labral tears and three posterior labral tears seen on arthroscopy but not seen on MR examination.

CONCLUSION

In this series, a high percentage of SLAP tears and posterior labral tears described on MR examination did not have surgical tacking. Most anterior labral tears had surgical tacking. Based on the above, our surgeons request we describe superior and posterior labral lesions as fraying and/or tearing, unless we can see a displaced tear. Most anterior labral lesions are treated with surgical tacking.

ADVANCES IN KNOWLEDGE

MRI allows for sensitive detection of labral tears. The tears often are not clinically significant.

Reflections on mental capacity assessments in general hospitals

Research suggests that a significant proportion of inpatients in general medical wards may lack capacity to make treatment decisions, a situation that often goes unrecognised by clinicians. We would like to briefly discuss two cases from a non-psychiatric setting, where a mental disorder served to inhibit the individual's ability to weigh-up associated risks when deciding to refuse potentially life-sustaining healthcare interventions. In both cases the history of mental disorder was well established yet, for markedly different reasons, the respective presentation was such that the influence of the disorder on decision-making was not evident to the treating teams.

Congenital constriction band with pseudoarthrosis of the tibia: a case report and literature review

A passive constriction phenomenon has been proposed to explain the development of congenital pseudoarthrosis of the tibia. We report a case of congenital pseudoarthrosis of the tibia in a child with congenital constriction band syndrome, successfully treated with soft tissue release (cutaneous and deep) only, restoring normal periosteal blood supply and enabling gradual correction of the angular osseous deformity and reformation of the intramedullary canal.

Computed tomography-detected abnormalities following conventional abdominal aortic aneurysm (AAA) repair

PURPOSE

To determine how time since the operation influences vascular abnormalities following conventional infrarenal abdominal aortic aneurysm (AAA) repair.

METHODS

In 47 patients computed tomography was performed 1 to 12 years following the aneurysm repair. Aortic diameters at different levels were measured and other abnormalities recorded.

RESULTS

Significant correlation was found between time since operation and diameter of the suprarenal aorta (R=0.51, P<0.001) but not with aortic neck diameter (R=-0.10, P=0.48) or diameter of the prosthetic graft (R=0.07, P=0.66). However, measured diameters of graft and aortic neck showed a significant positive correlation (R=0.40, P=0.005).

CONCLUSIONS

Dilatation of the suprarenal aorta has a different pattern from aortic neck dilatation. The latter showed correlation with the diameter of the prosthetic graft. This may be of interest for future design of endovascular stent-grafts.

Soft tissue twisting injuries of the knee

OBJECTIVE

Twisting injuries occur as a result of differential motion of different tissue types in injuries with some rotational force. These injuries are well described in brain injuries but, to our knowledge, have not been described in the musculoskeletal literature. We correlated the clinical examination and MR findings of 20 patients with twisting injuries of the soft tissues around the knee.

DESIGN AND PATIENTS

We prospectively followed the clinical courses of 20 patients with knee injuries who had clinical histories and MR findings to suggest twisting injuries of the subcutaneous tissues. Patients with associated internal derangement of the knee (i.e., meniscal tears, ligamentous or bone injuries) were excluded from this study. MR findings to suggest twisting injuries included linear areas of abnormal dark signal on T1-weighted sequences and abnormal bright signal on T2-weighted or short tau inversion recovery (STIR) sequences and/or signal to suggest hemorrhage within the subcutaneous tissues. These MR criteria were adapted from those established for indirect musculotendinous junction injuries.

RESULTS

All 20 patients presented with considerable pain that suggested internal derangement on physical examination by the referring orthopedic surgeons. All presented with injuries associated with rotational force. The patients were placed on a course of protected weight-bearing of the affected extremity for 4 weeks. All patients had pain relief by clinical examination after this period of protected weight-bearing.

CONCLUSIONS

Twisting injuries of the soft tissues can result in considerable pain that can be confused with internal derangement of the knee on physical examination. Soft tissue twisting injuries need to be recognized on MR examinations as they may be the cause of the patient's pain despite no MR evidence of internal derangement of the knee. The demonstration of soft tissue twisting injuries in a patient with severe knee pain but no documented internal derangement on MR examination may allow the orthopedic surgeon to elect for a trial of conservative nonsurgical management.

Reshaping primary care: the Healthy Steps Initiative

The Healthy Steps Initiative, funded by the Commonwealth Fund in New York and developed and implemented by Boston University School of Medicine, is an enhanced approach to pediatric care in the first 3 years of life. The goals of this effort in transforming pediatric care include (a) supporting the physical and emotional development of each infant and young child; (b) supporting a parental sense of confidence in their child-rearing knowledge and skills; and (c) supporting the clinical effectiveness of pediatric primary care practices to meet the needs of young children and families. The Healthy Steps Initiative enhances well-child care to achieve these goals by providing child development information and support as part of an expanded approach to pediatric primary care. Healthy Steps offers both pediatric practices and families a vehicle for meeting the needs of infants and young children within a preventative framework. This unique program, which is being quantitatively and qualitatively evaluated over 3 years, has been initiated in more than 24 pediatric sites nationwide.

Association of paralabral cysts with acetabular disorders

OBJECTIVE

Acetabular labral tears may cause considerable pain and predispose patients to premature osteoarthritis. Therefore, early and accurate examination is required. Acetabular labral tears are difficult to view on MR images. We report the association of paralabral ganglion cysts detected on MR imaging with surgically proven acetabular labral disorders.

CONCLUSION

Paralabral cysts may be associated with labral disorders. The appearance of a paralabral cyst on MR imaging is a useful indirect sign of acetabular labral abnormality. Use of this sign may enable earlier and more accurate examination of labral disorders.

Finasteride, a 5alpha-reductase inhibitor, blocks the anticonvulsant activity of progesterone in mice

Progesterone is an effective anticonvulsant against pentylenetetrazol (PTZ) seizures. This action is hypothesized to require the metabolic conversion of progesterone to the gamma-aminobutyric acidA receptor potentiating neuroactive steroid allopregnanolone by 5alpha-reductase isoenzymes followed by 3alpha-hydroxy oxidoreduction. We evaluated this possibility using the competitive 5alpha-reductase inhibitor finasteride. Progesterone (50-200 mg/kg, i.p.) protected mice against PTZ-induced seizures in a dose-dependent manner (ED50, 94 mg/kg). Pretreatment with finasteride (50-300 mg/kg, i.p.) produced a dose-dependent (ED50, 146 mg/kg) reversal of the protective effects of progesterone (2 x ED50 dose = 188 mg/kg). In contrast, finasteride (up to 300 mg/kg) failed to affect the anticonvulsant activity of allopregnanolone (10-30 mg/kg, i.p.; ED50, 12 mg/kg). Finasteride (up to 300 mg/kg) did not block the protective effect of high doses of progesterone (250-350 mg/kg) on tonic hindlimb extension in the maximal electroshock seizure test (progesterone ED50, 235 mg/kg). The anticonvulsant activity of progesterone against PTZ-induced seizures can be blocked by 5alpha-reductase inhibition, providing strong evidence that the anticonvulsant effect of the steroid in this model is mediated by its active metabolite allopregnanolone.

Cloning of rat and human inducible penile nitric oxide synthase. Application for gene therapy of erectile dysfunction

Erectile dysfunction is mainly due to the inability of the cavernosal smooth muscle of the penis to undergo complete relaxation. In the aging rat model, erectile dysfunction is accompanied by a reduction of penile smooth muscle compliance and, in very old animals, by a decrease in penile nitric oxide synthase (NOS), which is responsible for the synthesis of the mediator of penile erection, nitric oxide (NO). We have investigated whether the stimulation of penile NOS expression by local induction or gene therapy can mitigate erectile dysfunction in the aged rat. A mix of iNOS (inducible NOS) inducers was continuously delivered to the penises of 5- ("adult"), 20- ("old"), and 30- ("very old") mo-old rats for 3-6 days, and the erectile response to electrical field stimulation of the cavernosal nerve was measured. The erectile dysfunction observed in old and very old rats as compared to adult animals was ameliorated by treatment with iNOS inducers. Penile iNOS was detectable in the penis of these rats by Western blot, NADPH diaphorase, and NOS activity assays. Inducible NOS was inducible in vitro in both rat and human corpora cavernosal tissue and in rat penile smooth muscle cells (RPSMC), as shown by Western blots. However, NO synthesis in cavernosal tissue upon iNOS protein induction remained low, indicating that the increased NOS levels were under physiological control. The iNOS cDNA was cloned from induced RPSMC mRNA and generated by reverse transcriptase polymerase chain reaction (RT-PCR) from induced human penile smooth muscle cells and corporal tissue. The coding regions from both the rat (RPiNOS) and human (HPiNOS) penile iNOS showed several amino acid differences from their analogous isoform in nonpenile tissues. RPiNOS cDNA injected into the penis mitigated the aging-associated erectile dysfunction. The iNOS construct was detected in cavernosal tissue by PCR, and its expression by RT-PCR and Western blots. These results open the way for the possible use of NOS isoforms in the management of erectile dysfunction.

Cloning of a novel neuronal nitric oxide synthase expressed in penis and lower urinary tract

The neuronal nitric oxide synthase (nNOS) is the main NOS isoform in the urogenital tract catalyzing the synthesis of nitric oxide, the mediator of penile erection and presumably an important factor in the control of urinary voiding. We have cloned from the rat penile corpora cavernosa a cDNA coding for a novel nNOS differing from the cerebellar nNOS by the presence of a 102 nucleotides stretch and other features. This new species is the only nNOS mRNA expressed in the rat penis, urethra, prostate, and skeletal muscle, coexists with the cerebellar nNOS in the pelvic plexus and bladder, and is detectable in the cerebellum. The novel insert is present in human penile RNA and is transcribed from intron 16. The features and distribution of the penile nNOS suggest that it is may be regulated differentially from the cerebellar nNOS.

The role of lipid anchors for small G proteins in membrane trafficking

Small GTP-binding proteins of the Ras superfamily play diverse roles in intracellular trafficking. In order to perform these functions, the proteins must associate with specific donor vesicles and be recycled after fusion of these vesicles with their acceptor membrane target. Recent results have identified a number of lipid modifications of these proteins, occurring at the N- or C-termini, that contribute to their membrane binding. Recycling appears, in some cases, to be mediated by soluble proteins that bind the lipid-modified tails, removing them from the membrane and allowing their reutilization via the cytosol.

Normal anatomy and pathologic conditions of ankle tendons: current imaging techniques

Radiologic assessment of tendon injuries requires familiarity with normal anatomy and the capabilities of available imaging modalities. Tenography, less commonly used nowadays, does not allow direct visualization of tendons, so that partial ruptures and longitudinal splits may go undetected. Ultrasonography can depict tenosynovitis, tendinitis, and complete tendon rupture of the Achilles tendon, but the other tendons are difficult to visualize with this technique. Magnetic resonance (MR) imaging is superior to computed tomography (CT) in the depiction of tenosynovitis and peritendinitis, tendinitis, tendon rupture, and tendon dislocation and subluxation. CT can demonstrate these abnormalities, but accompanying scar tissue or edema, early changes of tendon degeneration, and small amounts of inflammatory fluid are difficult to differentiate with this technique. CT is superior for demonstrating calcifications, convex retromalleolar groove, bone fragments, or spurs that complicate tendon dislocation and rupture. Although the authors prefer MR imaging, they caution that all of the modalities are not always specific and that differentiation between closely related processes such as tendinitis and early tendon rupture is difficult.

Ventricular arrhythmias after coronary artery bypass graft surgery: incidence, risk factors and long-term prognosis

The incidence, risk factors and long-term prognosis of complex ventricular arrhythmias after coronary artery bypass graft surgery are not known. Complex ventricular arrhythmias are defined as Lown grades 4a (couplets), 4b (ventricular tachycardia) and 5 (R on T phenomenon). Ninety-two patients with normal left ventricular function who underwent elective coronary artery bypass graft surgery were prospectively evaluated. Ventricular arrhythmias were documented by predischarge 24 hour ambulatory electrocardiographic monitoring; 43% of patients had no or simple ventricular arrhythmias (Lown grades 1 to 3) and 57% had complex ventricular arrhythmias. Risk factors analyzed included age, sex, diabetes, hypertension, smoking, preoperative digoxin or propranolol therapy, cardiopulmonary bypass time, aortic cross-clamp time, number of vessels bypassed, peak creatine kinase (CK) elevation and pericarditis. No risk factor identified patients at higher risk for complex ventricular arrhythmias. Patients were followed up for 6 to 24 months (mean 16). Patients with complex ventricular arrhythmias did not have a higher incidence of sudden death, cardiac death, syncope, angina, myocardial infarction or cerebrovascular accident. It was concluded that: Complex ventricular arrhythmias are common after coronary artery bypass graft surgery. None of the risk factors considered identify high risk patients. Complex ventricular arrhythmias after coronary artery bypass graft surgery do not indicate a poor prognosis in patients with normal left ventricular function.