The JAZ family of repressors is the missing link in jasmonate signalling

Jasmonates are essential phytohormones for plant development and survival. However, the molecular details of their signalling pathway remain largely unknown. The identification more than a decade ago of COI1 as an F-box protein suggested the existence of a repressor of jasmonate responses that is targeted by the SCF(COI1) complex for proteasome degradation in response to jasmonate. Here we report the identification of JASMONATE-INSENSITIVE 3 (JAI3) and a family of related proteins named JAZ (jasmonate ZIM-domain), in Arabidopsis thaliana. Our results demonstrate that JAI3 and other JAZs are direct targets of the SCF(COI1) E3 ubiquitin ligase and jasmonate treatment induces their proteasome degradation. Moreover, JAI3 negatively regulates the key transcriptional activator of jasmonate responses, MYC2. The JAZ family therefore represents the molecular link between the two previously known steps in the jasmonate pathway. Furthermore, we demonstrate the existence of a regulatory feed-back loop involving MYC2 and JAZ proteins, which provides a mechanistic explanation for the pulsed response to jasmonate and the subsequent desensitization of the cell.

The efficacy of automated "disease/no disease" grading for diabetic retinopathy in a systematic screening programme

AIM

To assess the efficacy of automated "disease/no disease" grading for diabetic retinopathy within a systematic screening programme.

METHODS

Anonymised images were obtained from consecutive patients attending a regional primary care based diabetic retinopathy screening programme. A training set of 1067 images was used to develop automated grading algorithms. The final software was tested using a separate set of 14 406 images from 6722 patients. The sensitivity and specificity of manual and automated systems operating as "disease/no disease" graders (detecting poor quality images and any diabetic retinopathy) were determined relative to a clinical reference standard.

RESULTS

The reference standard classified 8.2% of the patients as having ungradeable images (technical failures) and 62.5% as having no retinopathy. Detection of technical failures or any retinopathy was achieved by manual grading with 86.5% sensitivity (95% confidence interval 85.1 to 87.8) and 95.3% specificity (94.6 to 95.9) and by automated grading with 90.5% sensitivity (89.3 to 91.6) and 67.4% specificity (66.0 to 68.8). Manual and automated grading detected 99.1% and 97.9%, respectively, of patients with referable or observable retinopathy/maculopathy. Manual and automated grading detected 95.7% and 99.8%, respectively, of technical failures.

CONCLUSION

Automated "disease/no disease" grading of diabetic retinopathy could safely reduce the burden of grading in diabetic retinopathy screening programmes.

Audiological issues in children with cleft lip and palate in one area of the U.K

OBJECTIVE

The purpose of this study was to determine the extent of multidisciplinary care and audiological services rendered to children with CL/P who underwent surgical repair of the cleft in 1998 and 1999. This followed proposals to radically reorganize cleft lip and palate services in the U.K. after unsatisfactory findings in a national review.

METHOD

Information was obtained from questionnaires sent to clinicians (audiologists; ear, nose, and throat surgeons; and community pediatricians) from audiology teams, and parents were asked to retrieve information from their Personal Child Health Record. Standards chosen were based on the Clinical Standards Advisory Group, the South Thames Audiology Audit Group, and the National Deaf Children's Society.

RESULTS

None of the agreed standards were achieved at an acceptable level.

CONCLUSIONS

This demonstrates the need for better communication systems between teams, including better use by parents and professionals of the Personal Child Health Record. A clinical care pathway is suggested here with other recommendations.

[Pediatric Guillain-Barré syndrome. Experience in the Neuropediatrics Unit of a Portuguese hospital]

INTRODUCTION

Guillain-Barré syndrome (GBS) is an acute inflammatory ascending polyradiculoneuropathy. Autoimmune mechanisms play a role in the demyelinating process. Clinically, progressive symmetric loss of motor strength, areflexia, sensitive and autonomic manifestations are observed. Albuminocytological dissociation and electrophysiological signs of demyelination are frequently found. It is the most common cause of acute flaccid paralysis in children.

PATIENTS AND METHODS

Retrospective review of all children with GBS admitted to Garcia de Orta Hospital in a 10 year period (1994-2003).

RESULTS

17 children (18 months to 14 years) were admitted during this period. Respiratory or gastrointestinal prodrome was identified in 15 children, with positive serologic studies in six. The main clinical manifestations were disturbances of gait, progressive muscular weakness, sensitive manifestations (pain, paresthesias) and osteotendinous areflexia. 13 children had albuminocytological dissociation and acute demyelinating neuropathy was identified in 12.64% of children were treated with immunoglobulins (2 g/kg). Clinical evolution was favourable in 16 cases, with a death secondary to autonomic dysfunction.

CONCLUSIONS

Clinical presentation may be unspecific, particularly in young patients, with pain as a primary complaint, preceding muscular weakness and areflexia. Increased cerebrospinal protein and abnormal electrodiagnostic studies may be absent in the early course of GBS. Immunoglobulin therapy was efficacious and well-tolerated.

School hearing screening programme in the UK: practice and performance

BACKGROUND

Paediatric audiology services and screening programmes are currently under review.

AIMS AND METHODS

To investigate current practice and performance of the school hearing screening programme (SHSP) by means of a questionnaire.

RESULTS

SHSP was found to detect previously unrecognised hearing loss at low cost. Wide variation in practice was shown, and the majority of services had no computerised system for data collection.

CONCLUSION

There is a need for nationally agreed protocols and quality assurance procedures.

Impact of positive legionella urinary antigen test on patient management and improvement of antibiotic use

AIM

To assess the incidence of legionella infection over a 27 month period at a large university hospital.

MATERIAL AND METHODS

The present retrospective cohort study enrolled patients with legionellosis, defined as those presenting a positive urinary antigen for legionella together with a medical history, clinical findings, and radiological findings consistent with pneumonia. These patients were evaluated to determine the relation between their test results and changes in treatment modalities. A control group of patients with pneumonia but a negative urinary antigen test for legionella were also analysed.

RESULTS

Twenty seven of 792 assessed patients tested positive for legionella. In 22 of these patients, legionella active antibiotics were administered empirically. In seven patients, the test results prompted a legionella specific treatment, whereas in 12 cases, non-specific antibiotics were stopped within 24 hours. Overall, treatment was altered in more than half of the patients as a result of the test results.

CONCLUSIONS

The urinary antigen may have a direct impact on clinical management of pulmonary legionellosis. However, patient comorbidities and individual clinical judgment are still important for determining the best treatment to be given in each individual case.

Effect of telmisartan 80 mg once daily on 24-h blood pressure profile in patients with mild-to-moderate hypertension failing to respond to prior antihypertensive therapy

Blood pressure is not adequately controlled in almost 50% of patients with hypertension who are in receipt of antihypertensive therapy. This multicentre, prospective, open-label trial was designed to determine whether or not once-daily telmisartan 80 mg reduced blood pressure during the last 6 h of the 24-h dosing interval in patients with mild-to-moderate hypertension who were unresponsive to previous antihypertensive therapy. The study comprised 100 patients (47 males, 53 females) who had failed to respond satisfactorily to prior treatment given for a minimum of 3 months. At screening, 24-h ambulatory blood pressure monitoring (ABPM) was conducted after the patient had been treated with the currently prescribed antihypertensive medication. Following 5 weeks of telmisartan 80 mg treatment, ABPM was repeated. Telmisartan significantly reduced mean systolic blood pressure, diastolic blood pressure (DBP) and pulse pressure compared with previous antihypertensive therapy over each time interval (24-h, morning, night-time and the last 6 h of the dosing interval [2.00 a.m.-8.00 a.m.]) analysed. In addition, more than 90% of patients responded successfully (clinic DBP <90 mmHg or a >10 mmHg reduction in clinic DBP) at the end of telmisartan treatment. In conclusion, telmisartan provides effective blood pressure control throughout the 24-h dosing interval in patients with mild-to-moderate hypertension who were unresponsive to previous antihypertensive medication.

Reactive phenotypes after acute and chronic NK-cell activation

Several phenotypic changes have been shown to occur after NK-cell stimulation, involving molecules that have been proved to regulate NK-cell migration into tissues and NK-cell activation and proliferation as well as target cell recognition and killing. Here, we review the reactive phenotypes observed in vivo after acute and chronic NK-cell activation.

Slow fiber cluster pattern in pig longissimus thoracis muscle: implications for myogenesis

Recent evidence implicates fiber type proportions as playing a role in meat eating quality, and in pigs it has been suggested that the slow oxidative fibers contribute to both juiciness and tenderness. The fiber distribution in pigs is different from that found in most other species, in which the various types of skeletal muscle fiber are distributed in a "checkerboard" pattern, because in pigs the slow oxidative fibers have a clustered distribution. The initial processes leading to fiber clustering are likely to occur during myogenesis, but the precise mechanistic aetiology of this patterning and whether the slow oxidative fiber clusters occur in a random or ordered fashion is unknown. In the present study longissimus thoracis muscle from Large White crossbred pigs was sampled at the 10th rib, 48 h postmortem. Transverse cryo-sections were cut and histochemically stained to allow the identification of the main muscle fiber types: slow oxidative, fast glycolytic, and fast oxidative glycolytic. Images of the sections were captured and analyzed using point processes and Voronoi Tesselations to examine the randomness and spatial distribution of the clusters of slow oxidative fibers found in pig longissimus thoracis muscle. The results showed that an assumption of complete spatial randomness can be rejected and that a mathematical model incorporating a minimum distance of 1.7 to 2.0 microm between cluster centers produced fiber patterns similar to those observed in the original transverse sections of the muscle. In addition, if it assumed that the central fiber in each cluster is derived from primary myoblast progenitors, these results suggest that there may be some degree of repulsion between the primary fibers during the initial stages of cluster formation. The mechanistic basis of such repulsion is not clear, but it is speculated that secreted factors, such as sonic hedgehog or myostatin may play a role.

Aggressive natural-killer cell lymphoma presenting with skin lesions, breast nodule, suprarenal masses and life-threatening pericardial and pleural effusions

We report the clinical and laboratory findings of a patient with an aggressive Epstein-Barr virus positive CD2+/CD56+ natural killer-cell lymphoma with a high mitotic activity and complex chromosomal abnormalities presenting with life-threatening pericardial and pleural effusions, disseminated skin lesions, breast nodule and large suprarenal masses. The clinical course was characterized by resistance to chemotherapy and relapsing pericardial and pleural effusions with respiratory and haemodynamic failure. Death occurred 4 months after the first manifestations of the disease as a consequence of cardiac tamponade.

Immunophenotypic Aberrations, DNA Content, and Cell Cycle Analysis of Plasma Cells in Patients with Myeloma and Monoclonal Gammopathies

We describe the immunophenotypic and gross DNA defects in 55 patients with myeloma and 50 patients with monoclonal gammopathy and review the literature on this subject (MedLine, 1994-2000). Our data confirmed previous reports indicating that in myeloma nearly all marrow plasma cells are abnormal (98.7 +/- 8.1%). In monoclonal gammopathy the fraction of abnormal plasma cells was 35.0 +/- 32.8%. In both myeloma and monoclonal gammopathy, the most frequent aberrant phenotypic features consisted of absence of expression of CD19, strong expression of CD56, and decreased intensity of expression of CD38; aberrant expression of CD10, CD20, CD22, or CD28 was observed in less than one-third of myeloma cases. The vast majority of cases had two or more phenotypic aberrations. In the DNA studies, 7% of myeloma cases were biclonal and 93% of cases were monoclonal. In those studies with only one plasma cell mitotic cycle, 37% had normal DNA content and 63% were aneuploid (hyperploid, 61%; hypoploid, 2%). The mean percentages of plasma cells in S- and G2M phases were 4.9 +/- 8.5 and 4.4 +/- 6.9%, respectively. Thirty-eight percent of cases had more than 3% of plasma cells in S phase. In monoclonal gammopathy, the DNA index of abnormal plasma cells ranged from 0.89 to 1.30 and the percentage of diploid (31%) and aneuploid (69%) cases was not different from the results found in myeloma. The differences in percentage of abnormal plasma cells in S- (7.4 +/- 8.6%) and G2M-phases (2.4 +/- 1.7%) in patients with monoclonal gammopathy were not statistically significant.

Identification of permanent hearing loss in children: are the targets for outcome measures attainable?

A collaborative nine-centre study was designed to follow the routes to identification of all children up to the age of seven years newly diagnosed with permanent hearing impairment (> or = 50 dB HL) during the period 1993-1994. Ages of identification were compared with the standards set by the National Deaf Children's Society (NDCS), ascertaining whether these targets could be achieved with current service provision. Of the 126 children identified, 104 had congenital sensorineural hearing loss: 19% were identified by the age of six months and 39% by their first year. These results fall short of the NDCS targets of 40% and 80%, respectively, and point to the need for modifications of current practice, such as the introduction of universal neonatal screening.

The relationship between audit, research and policy: lessons from a community paediatric audiology service

The pace of medical change is in danger of paralysing the process of decision making, particularly in services where clinical improvements occur more slowly than the introduction of new interventions. Audit within an individual district enables staff to monitor progress towards desired goals and standards but rarely generates sufficient data to inform decision making about major policy changes. The paper describes how the findings from nine audits of a community paediatric audiology service over a 13-year period were combined with reviews of the literature, resulting in a series of changes to a children's audiological service. The interest and commitment of all the staff involved were maintained by involving them in the process and using them as a valuable source of qualitative data. Audit must be thorough and should be based on precise case definition and comprehensive casefinding if the results are to be meaningful. It is a more powerful means of achieving improvements in systems if it is combined with research evidence, and a readiness to change the system if the agreed goals are not being attained.