Germline Cancer Susceptibility in Individuals with Melanoma

BACKGROUND

Prior studies have estimated a small number of individuals with melanoma (2-2.5%) have germline cancer predisposition, yet a recent twin study suggested melanoma has the highest hereditability among cancers.

OBJECTIVE

To determine the incidence of hereditary melanoma and characterize the spectrum of cancer predisposition genes that may increase the risk of melanoma.

METHODS

400 individuals with melanoma and personal or family history of cancers underwent germline testing of >80 cancer predisposition genes. Comparative analysis of germline data was performed on 3 additional oncologic and dermatologic datasets.

RESULTS

Germline pathogenic/likely pathogenic (P/LP) variants were identified in 15.3% (61) individuals with melanoma. Most variants (41, 67%) involved genes considered unrelated to melanoma (BLM, BRIP1, CHEK2, MLH1, MSH2, PMS2, RAD51C). A third (20, 33%) were in genes previously associated with familial melanoma (BAP1, BRCA2, CDKN2A, MITF, TP53). Nearly half (30, 46.9%) of P/LP variants were in HRD genes. Validation cohorts demonstrated P/LP rates of 10.6% from an unselected oncologic cohort, 15.8% from a selected commercial testing cohort and 14.5% from a highly selected dermatologic study.

LIMITATIONS

Cohorts with varying degrees of selection, some retrospective.

CONCLUSION

Germline predisposition in individuals with melanoma is common, with clinically actionable findings diagnosed in 10.6% to 15.8%.

Treatment-related changes in serum neutrophil gelatinase-associated lipocalin (NGAL) in psoriatic arthritis: results from the PIPA cohort study

OBJECTIVES

Obesity and psoriatic arthritis (PsA) have a complicated relationship. While weight alone does not cause PsA, it is suspected to cause worse symptoms. Neutrophil gelatinase-associated lipocalin (NGAL) is secreted through various cell types. Our objective was to assess the changes and trajectories in serum NGAL and clinical outcomes in patients with PsA during 12 months of anti-inflammatory treatment.

METHOD

This exploratory prospective cohort study enrolled PsA patients initiating conventional synthetic or biological disease-modifying anti-rheumatic drugs (csDMARDs/bDMARDs). Clinical, biomarker, and patient-reported outcome measures were retrieved at baseline, and 4 and 12 months. Control groups at baseline were psoriasis (PsO) patients and apparently healthy controls. The serum NGAL concentration was quantified by a high-performance singleplex immunoassay.

RESULTS

In total, 117 PsA patients started a csDMARD or bDMARD, and were compared indirectly at baseline with a cross-sectional sample of 20 PsO patients and 20 healthy controls. The trajectory in NGAL related to anti-inflammatory treatment for all included PsA patients showed an overall change of -11% from baseline to 12 months. Trajectories in NGAL for patients with PsA, divided into treatment groups, showed no clear trend in clinically significant decrease or increase following anti-inflammatory treatment. NGAL concentrations in the PsA group at baseline corresponded to the levels in the control groups. No correlation was found between changes in NGAL and changes in PsA outcomes.

CONCLUSION

Based on these results, serum NGAL does not add any value as a biomarker in patients with peripheral PsA, either for disease activity or for monitoring.

Effectiveness of patient education as a stand-alone intervention for patients with chronic widespread pain and fibromyalgia: a systematic review and meta-analysis of randomized trials

OBJECTIVE

Patient education is recommended as an integral component of the therapeutic plan for the management of chronic widespread pain (CWP) and fibromyalgia (FM). The key purpose of patient education is to increase the patient's competence to manage his or her own health requirements, encouraging self-management and a return to desired everyday activities and lifestyle. The aim of this systematic review was to evaluate the evidence for the benefits and potential harms associated with the use of patient education as a stand-alone intervention for individuals with CWP and FM through randomized controlled trials (RCTs).

METHOD

On 24 November 2021 a systematic search of PubMed, MEDLINE, Embase, CENTRAL, PsycINFO, CINAHL, ClinicalTrials.gov, American College of Rheumatology, European League Against Rheumatism, and the World Health Organization International Clinical Trials Registry Platform identified 2069 studies. After full-text screening, five RCT studies were found to be eligible for the qualitative evidence synthesis.

RESULTS

Patient education as a stand-alone intervention presented an improvement in patients' global assessment (standardized mean difference 0.79, 95% confidence interval 0.13 to 1.46). When comparing patient education with usual care, no intervention, or waiting list, no differences were found for functioning, level of pain, emotional distress in regard to anxiety and depression, or pain cognition.

CONCLUSION

This review reveals the need for RCTs investigating patient education as a stand-alone intervention for patients with FM, measuring outcomes such as disease acceptance, health-related quality of life, enhancement of patients' knowledge of pain, pain coping skills, and evaluation of prioritized learning outcomes.

A New Device for In Situ Dental Biofilm Collection Additively Manufactured by Direct Metal Laser Sintering and Vat Photopolymerization

Dental biofilms are complex medical biofilms that cause caries, the most prevalent disease of humankind. They are typically collected using handcrafted intraoral devices with mounted carriers for biofilm growth. As the geometry of handcrafted devices is not standardized, the shear forces acting on the biofilms and the access to salivary nutrients differ between carriers. The resulting variability in biofilm growth renders the comparison of different treatment modalities difficult. The aim of the present work was to design and validate an additively manufactured intraoral device with a dental bar produced by direct metal laser sintering and vat photopolymerized inserts with standardized geometry for the mounting of biofilm carriers. Additive manufacturing reduced the production time and cost, guaranteed an accurate fit of the devices and facilitated the handling of carriers without disturbing the biofilm. Biofilm growth was robust, with increasing thickness over time and moderate inter- and intraindividual variation (coefficients of variance 0.48-0.87). The biofilms showed the typical architecture and composition of dental biofilms, as evidenced by confocal microscopy and 16S rRNA gene sequencing. Deeper inserts offering increased protection from shear tended to increase the biofilm thickness, whereas prolonged exposure to sucrose during growth increased the biofilm volume but not the thickness. Ratiometric pH imaging revealed considerable pH variation between participants and also inside single biofilms. Intraoral devices for biofilm collection constitute a new application for medical additive manufacturing and offer the best possible basis for studying the influence of different treatment modalities on biofilm growth, composition, and virulence. The Clinical Trial Registration number is: 1-10-72-193-20.

Who are likely to benefit from the Good Life with osteoArthritis in Denmark (GLAD) exercise and education program? An effect modifier analysis of a randomised controlled trial

OBJECTIVE

To identify contextual factors that modify the treatment effect of the 'Good Life with osteoArthritis in Denmark' (GLAD) exercise and education programme compared to open-label placebo (OLP) on knee pain in individuals with knee osteoarthritis (OA).

METHODS

Secondary effect modifier analysis of a randomised controlled trial. 206 participants with symptomatic and radiographic knee OA were randomised to either the 8-week GLAD programme (n = 102) or OLP given as 4 intra-articular saline injections over 8 weeks (n = 104). The primary outcome was change from baseline to week 9 in the Knee injury and Osteoarthritis Outcome Score questionnaire (KOOS) pain subscale (range 0 (worst) to 100 (best)). Subgroups were created based on baseline information: BMI, swollen study knee, bilateral radiographic knee OA, sports participation as a young adult, sex, median age, a priori treatment preference, regular use of analgesics (NSAIDs or paracetamol), radiographic disease severity, and presence of constant or intermittent pain.

RESULTS

Participants who reported use of analgesics at baseline seem to benefit from the GLAD programme over OLP (subgroup contrast: 10.3 KOOS pain points (95% CI 3.0 to 17.6)). Participants with constant pain at baseline also seem to benefit from GLAD over OLP (subgroup contrast: 10.0 points (95% CI 2.8 to 17.2)).

CONCLUSIONS

These results imply that patients who take analgesics or report constant knee pain, GLAD seems to yield clinically relevant benefits on knee pain when compared to OLP. The results support a stratified recommendation of GLAD as management of knee OA.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03843931. EudraCT number 2019-000809-71.

Racial Disparities in Family Variant Testing for Cancer Predisposition Genes

PURPOSE

Despite the substantial clinical impact of genetic testing, racial disparities exist in the delivery of this service. Here, we partnered with a commercial laboratory (Invitae) to establish whether there are racial disparities in the uptake of family variant testing (FVT). We also investigated if providing FVT at no cost impacts rates of cascade testing in Black and White families.

METHODS

This is a retrospective analysis comparing rates of FVT in self-reporting Black probands to self-reporting White probands who underwent germline genetic testing for genes associated with hereditary cancer through Invitae. All Black and White patients found to have a pathogenic/likely pathogenic variant P/LPV) in a hereditary cancer syndrome gene were identified up to one year before and up to one year after FVT became no-charge in 1/2017. The proportion of probands with at least one at- risk family member who underwent FVT was compared between Black and White probands using logistic regression, including the interaction between covariates of cost and race.

RESULTS

Between 1/2016 and 1/2018, 8,530 Black and 87,846 White probands underwent genetic testing. Of these, 9.3% (n =791) Black probands and 11.4% (n=9,998) White probands had a P/LPV identified. The uptake of FVT, defined by percentage of positive probands with at least one family member undergoing testing, was significantly lower in Black participants compared to White participants (11.9% versus 21.7%, odds ratio 0.5, 95% CI 0.4-0.6, p<0.001). Period of testing before or after FVT was no-charge did not impact this difference (p=0.23 for the interaction). FVT rates were significantly lower in Black patients compared to White patients both before (8.1% versus 18.7%, OR 0.4, 95% CI 0.2-0.6, p<0.001) and after (13.6% versus 23.1%, OR 0.5, 95% CI 0.4-0.7, p<0.001) testing became no-charge.

CONCLUSION

While FVT rates were low overall, they were significantly lower in Black families compared to White families. Cost of FVT did not have a significant impact on the racial disparity seen, suggesting additional barriers exist. Recognizing these disparities and determining the contributing factors are crucial to developing tailored interventions that would ultimately advance racial equity in cancer care.

Innate glycosidic activity in metallic implants for localized synthesis of antibacterial drugs

The unexpected discovery presented herein is that industrialized metallic wires can perform conversion of the glucuronide prodrugs with ensuing antibacterial effects.

Poor replicability of recommended exercise interventions for knee osteoarthritis: a descriptive analysis of evidence informing current guidelines and recommendations

OBJECTIVE

To examine the reporting completeness of exercise-based interventions for knee osteoarthritis (OA) in studies that form the basis of current clinical guidelines, and examine if the clinical benefit (pain and disability) from exercise is associated with the intervention reporting completeness.

DESIGN

Review of clinical OA guidelines METHODS: We searched MEDLINE and EMBASE for guidelines published between 2006 and 2016 including recommendations about exercise for knee OA. The studies used to inform a recommendation were reviewed for exercise reporting completeness. Reporting completeness was evaluated using a 12-item checklist; a combination of the Template for Intervention Description and Replication (TIDieR) and Consensus on Exercise Reporting Template (CERT). Each item was scored 'YES' or 'NO' and summarized as a proportion of interventions with complete descriptions and each intervention's completeness was summarized as the percentage of completely described items. The association between intervention description completeness score and clinical benefits was analyzed with a multilevel meta-regression.

RESULTS

From 10 clinical guidelines, we identified 103 original studies of which 100 were retrievable (including 133 interventions with 6,926 patients). No interventions were completely described on all 12 items (median 33% of items complete; range 17-75%). The meta-regression analysis indicated that poorer reporting was associated with greater effects on pain and no association with effects on disability.

CONCLUSION

The inadequate description of recommended interventions for knee OA is a serious problem that precludes replication of effective interventions in clinical practice. By consequence, the relevance and usability of clinical guideline documents and original study reports are diminished.

PROSPERO

CRD42016039742.

Combatting implant-associated biofilms through localized drug synthesis

Bacterial contamination of implantable biomaterials is a significant socioeconomic and healthcare burden. Indeed, bacterial colonization of implants after surgery has a high rate of incidence whereas concurrent prophylaxis using systemic antibiotics has limited clinical success. In this work, we develop enzyme-prodrug therapy (EPT) to prevent and to treat bacteria at interfaces. Towards the overall goal, novel prodrugs for fluoroquinolone antibiotics were developed on a privileged glucuronide scaffold. Whereas carbamoyl prodrugs were not stable and not suitable for EPT, glucuronides containing self-immolative linker between glucuronic acid masking group and the antibiotic were stable in solution and readily underwent bioconversion in the presence of β-glucuronidase. Surface coatings for model biomaterials were engineered using sequential polymer deposition technique. Resulting coatings afforded fast prodrug conversion and mediated antibacterial measures against planktonic species as evidenced by pronounced zone of bacterial growth inhibition around the biomaterial surface. These biomaterials coupled with the glucuronide prodrugs also effectively combatted bacteria within established biofilms and also successfully prevented bacterial colonization of the surface. To our knowledge, this is the first report of EPT engineered to the surface of biomaterials to mediate antibacterial measures.

A core domain set for hidradenitis suppurativa trial outcomes: an international Delphi process

BACKGROUND

There is no consensus on core outcome domains for hidradenitis suppurativa (HS). Heterogeneous outcome measure instruments in clinical trials likely leads to outcome-reporting bias and limits the ability to synthesize evidence.

OBJECTIVES

To achieve global multistakeholder consensus on a core outcome set (COS) of domains regarding what to measure in clinical trials for HS.

METHODS

Six stakeholder groups participated in a Delphi process that included five anonymous e-Delphi rounds and four face-to-face consensus meetings to reach consensus on the final COS. The aim was for a 1 : 1 ratio of patients to healthcare professionals (HCPs).

RESULTS

A total of 41 patients and 52 HCPs from 19 countries in four continents participated in the consensus process, which yielded a final COS that included five domains: pain, physical signs, HS-specific quality of life, global assessment and progression of course. A sixth domain, symptoms, was highly supported by patients and not by HCPs but is recommended for the core domain set.

CONCLUSIONS

Routine adoption of the COS in future HS trials should ensure that core outcomes of importance to both patients and HCPs are collected.

Association between alcohol, cannabis, and other illicit substance abuse and risk of developing schizophrenia: a nationwide population based register study

BACKGROUND

Several studies have examined whether use of substances can cause schizophrenia. However, due to methodological limitations in the existing literature (e.g. selection bias and lack of adjustment of co-abuse) uncertainties still remain. We aimed to investigate whether substance abuse increases the risk of developing schizophrenia, addressing some of these limitations.

METHOD

The longitudinal, nationwide Danish registers were linked to establish a cohort of 3 133 968 individuals (105 178 673 person-years at risk), identifying 204 505 individuals diagnosed with substance abuse and 21 305 diagnosed with schizophrenia. Information regarding substance abuse was extracted from several registers and did not include psychotic symptoms caused by substance abuse in the definition. This resulted in a large, generalizable sample of exposed individuals. The data was analysed using Cox regression analyses, and adjusted for calendar year, gender, urbanicity, co-abuse, other psychiatric diagnosis, parental substance abuse, psychiatric history, immigration and socioeconomic status.

RESULTS

A diagnosis of substance abuse increased the overall risk of developing schizophrenia [hazard ratio (HR) 6.04, 95% confidence interval (CI) 5.84-6.26]. Cannabis (HR 5.20, 95% CI 4.86-5.57) and alcohol (HR 3.38, 95% CI 3.24-3.53) presented the strongest associations. Abuse of hallucinogens (HR 1.86, 95% CI 1.43-2.41), sedatives (HR 1.68, 95% CI 1.49-1.90), and other substances (HR 2.85, 95% CI 2.58-3.15) also increased the risk significantly. The risk was found to be significant even 10-15 years subsequent to a diagnosis of substance abuse.

CONCLUSION

Our results illustrate robust associations between almost any type of substance abuse and an increased risk of developing schizophrenia later in life.

Epilepsy among children in Greenland

INTRODUCTION

Epilepsy has been considered to be more frequent in Greenland than in Denmark, where the prevalence among children is 0.40%.

STUDY DESIGN

Evaluation of the prevalence, diagnosis and treatment of epilepsy among children in Greenland aged 0-15 years.

METHODS

During autumn 2000, 13 out of 18 hospitals in Greenland were visited. The population of children in the areas visited was 11,965 of a total of 15,226 in Greenland. All children with the diagnosis of epilepsy were referred for evaluation and the diagnosis was confirmed. When possible, informed consent was obtained to collect data from medical records.

RESULTS

43 children (18 boys) had the diagnosis of epilepsy. For 38 (15 boys) further data were obtained. Mean age was 8.5 years (3-14) for boys and 7.9 years (2-14) for girls. The age at diagnosis was 4.9 years (1-11) for boys and 4.2 years (0-10) for girls. The prevalence of epilepsy was 0.34%. In 31 cases an electroencephalograph (EEG) recording was done, comprising sleep recordings in 26 cases. Medication was according to recommendations in Denmark.

CONCLUSION

The prevalence of epilepsy in children and the medical treatment of epilepsy among children in Greenland is the same as in Denmark.

Clinical features and outcome in a Danish cohort of juvenile dermatomyositis patients

OBJECTIVES

To assess disease characteristics and outcome in Danish juvenile dermatomyositis (JDM) patients (1977-2007).

METHODS

Medical record review of hospital records identified from the National Patient Register.

RESULTS

Fifty-seven JDM patients were identified. Follow-up time was 7 years (range 0.06-30). Female:male ratio was 2.5:1. Mean age at disease onset was 7 years (SD±3.7), range 1.5-16.0 years. Diagnostic delay was 0.7 years (SD±1.6), range 0.04-9 years. Mean disease duration was 3.7 years (SD±3.5), range 0.7-9 years. Thirty-nine patients (70%) were in full remission. Three patients (5%) were deceased. Disease/treatment-induced damage was present in 35 (61%) patients. Decreased pulmonary function occurred early in the disease course (median 10 months), osteoporosis and calcinosis occurred later (median 18 and 22 months). Four patients developed persistent damage within the first 6 months, four developed calcinosis within the first year. Shorter disease duration was associated with less damage (p=0.004). In a multivariate assessment analysis age >10 years at disease onset was associated with more damage (p<0.01), OR 10.96 (CI 1.6-73.6), and disease duration >4 years was associated with calcinosis (p=0.01) OR 23.2 (CI 2.6-206.2).

CONCLUSIONS

We present a nationwide retrospective study of Danish JDM patients from 1977-2007. Although 70% were in remission, 61% of the patients had clinical signs of damage. Only a few patients developed damage within the first year of the disease. Longer disease duration and higher age at disease onset was correlated with more disease damage.

Association of the M blood group system with bovine mastitis

Associations of the 11 bovine blood group systems with mastitis were examined in Red Danish dairy cattle. The mastitis status was followed during three lactational periods. A significant effect of the M blood group system on mastitis incidence was observed in the first and second lactation periods and a lower frequency of mastitis is found among animals lacking the M' factor as compared to those having the M' blood group factor. The significance of these results are discussed in view of the close relation between the M blood group system and the bovine lymphocyte antigens (BoLA), and the expected effect of eliminating the M' gene from the breed is estimated. Among the remaining 10 blood group systems, the T' system was the only system showing an overall effect on mastitis, and only in first and third lactation. However, the T' system was inconsistent with regard to the effect of the T' gene on the various mastitis diagnoses.

Etiology of common childhood acute lymphoblastic leukemia: the adrenal hypothesis

The pattern of infections in the first years of life modulates our immune system, and a low incidence of infections has been linked to an increased risk of common childhood acute lymphoblastic leukemia (ALL). We here present a new interpretation of these observations--the adrenal hypothesis--that proposes that the risk of childhood ALL is reduced when early childhood infections induce qualitative and quantitative changes in the hypothalamus-pituitary-adrenal axis that increase plasma cortisol levels. This may directly eliminate leukemic cells as well as preleukemic cells for the ALL subsets that dominate in the first 5-7 years of life and may furthermore suppress the Th1-dominated proinflammatory response to infections, and thus lower the proliferative stress on pre-existing preleukemic cells.

Constitutive activation of tethered-peptide/corticotropin-releasing factor receptor chimeras

Constitutive activity, or ligand-independent activity, of mutant G protein-coupled receptors (GPCRs) has been described extensively and implicated in the pathology of many diseases. Using the corticotropin-releasing factor (CRF) receptor and the thrombin receptor as a model, we present a ligand-dependent constitutive activation of a GPCR. A chimera in which the N-terminal domain of the CRF receptor is replaced by the amino-terminal 16 residues of CRF displays significant levels of constitutive activation. The activity, as measured by intracellular levels of cAMP, is blocked in a dose-dependent manner by the nonpeptide antagonist antalarmin. These results support a propinquity effect in CRF receptor activation, in which the amino-terminal portion of the CRF peptide is presented to the body of the receptor in the proper proximity for activation. This form of ligand-dependent constitutive activation may be of general applicability for the creation of constitutively activated GPCRs that are regulated by peptide ligands such as CRF. These chimeras may prove useful in analyzing mechanisms of receptor regulation and in the structural analysis of ligand activated receptors.

Electroconvulsive stimuli enhance both neuropeptide Y receptor Y1 and Y2 messenger RNA expression and levels of binding in the rat hippocampus

Repeated electroconvulsive stimulations and other seizure modalities produce an increase in neuropeptide Y synthesis and local release in the rat hippocampus, and perhaps as a consequence, a change in the concentration of neuropeptide Y binding sites in the same region. The aim of the present study was to determine possible changes in the expression of neuropeptide Y receptor subtypes affected by repeated stimulations in the hippocampus. Rats were exposed to 14 daily stimulations, and the brains were removed 24h after the last stimulation. For in vitro receptor autoradiography and in situ hybridisation histochemistry, the brains were frozen, sectioned, and levels of neuropeptide Y binding sites and messenger RNA expressions were determined quantitatively on sections from the same animals. In order to determine the contribution of different neuropeptide Y receptor subtypes, serial sections were incubated with either 125I-labelled peptide YY alone or the same radio-labelled peptide mixed with an excess of a number of displacing compounds with affinity for either neuropeptide Y receptor subtype Y1, Y2, or both. Binding studies revealed that the majority of peptide YY binding sites was represented by Y2, and that electroconvulsive stimulations reduced the binding capacity or the concentration of this receptor. A prominent reduction of Y1-preferring binding sites was determined in the dentate gyrus, and to a lesser extent in the CA1 and CA3 regions. Similarly, the treatment produced a significant reduction of Y2-preferring binding sites in the CA1 and CA3 region, but not in the granular cell layer of the dentate gyrus. Using semi-quantitative in situ hybridization, Y1 receptor messenger RNA level in the granular cell layer of the dentate increased by the stimulations. In the same region, Y2 receptor messenger RNA was expressed in low to undetectable amounts, but after the repeated stimulations, this transcript was found in moderate to high levels. These data suggest that the neuropeptide Yergic system in the dentate gyrus and the pyramidal cell layer are affected by the treatment, and that this includes both Y1 and Y2 receptor subtypes. Because levels of messenger RNA and binding are distinctly regulated, the turnover of both Y1 and Y2 molecules is strongly increased under electroconvulsive stimulations, suggesting that the intrahippocampal neuropeptide Yergic neurotransmission is also increased under the stimulations.

Disulfide bridge engineering in the tachykinin NK1 receptor

As in most other seven-transmembrane receptors, the central disulfide bridge from the extracellular end of TM-III to the middle of the second extracellular loop was essential for ligand binding in the NK1 receptor. However, introduction of "extra", single Cys residues in the second extracellular loop, at positions where disease-associated Cys substitutions impair receptor function in the vasopressin V2 receptor and in rhodopsin, did not cause mispairing with the Cys residues involved in this central disulfide bridge. Cys residues were introduced in the N-terminal extension and in the third extracellular loop, respectively, in such a way that disulfide bridge formation could be monitored by loss of substance P binding and breakage of the bridge could be monitored by gain of ligand binding. This disulfide bridge formed spontaneously in the whole population of receptors and could be titrated with low concentrations of reducing agent, dithiothreitol. Another putative disulfide bridge "switch" was constructed at the extracellular ends of TM-V and -VI, i.e., at positions where a high-affinity zinc site previously had been constructed with His substitutions. Disulfide bridge formation at this position, monitored by loss of binding of the nonpeptide antagonist [3H]LY303.870, occurred spontaneously only in a small fraction of the receptors. It is concluded that disulfide bridges form readily between Cys residues introduced appropriately in the N-terminal extension and the third extracellular loop, whereas they form with more difficulty between Cys residues placed at the extracellular ends of the transmembrane segments even at positions where high-affinity metal ion sites can be constructed with His residues.

[Arthritis as first symptom of leukemia in children]

Three children out of 30 (10%) referred for juvenile chronic arthritis had leukaemia. The patients had complained of intermittent musculoskeletal pain and painful joint swelling for three weeks, nine months and eighteen months prior to admission. On admission two of the patients had active arthritis with soft tissue swelling in one and three joints respectively. The third patient had only arthralgias and no joint swelling. All patients had slight anaemia, normal to slightly reduced thrombocyte count, slight neutropenia and absence of blasts in the peripheral blood. The correct diagnosis was made by bone marrow aspiration. Two children had acute lymphoblastic leukaemia and the third acute myeloblastic leukaemia. Leukaemia thus remains an important differential diagnosis in children presenting with musculoskeletal pain and/or arthritis.

[Randomized comparison of intravenous immunoglobulin and methylprednisolone pulse therapy in children with newly diagnosed idiopathic thrombocytic purpura. The Danish ITP Study Group]

Forty three children with newly diagnosed idiopathic thrombocytopenic purpura (ITP), platelet count (pl.c.) below 20 x 10(9)/l, and either clinically significant bleeding or failure to show a spontaneous platelet rise within three days of admission were randomly allocated to treatment with intravenous infusions of either immunoglobulin (IVIG) 1 g/kg or methylprednisolone (MPPT) 30 mg/kg on two consecutive days. Prompt induction of partial remission with pl.c. > 50 x 10(9)/l after 72 hours was seen in 21/23 given IVIG versus 10/20 given MPPT (exact p = 0.003); mean pl.c.s after 72 hours were 188 versus 77 x 10(9)/l (2p < 0.001). Poor responders were then given the alternative infusions in addition. After six days, complete remission with pl.c. > 150 x 10(9)/l was achieved in 16/23 versus 10/20 (p = 0.16). During six months follow-up, there were no significant differences regarding relapse rates or chronic course. Eleven children with relapse were crossed over to the alternative treatment arm: the estimated treatment effect in pl.c. after 72 hours was 134 x 10(9)/l in favour of IVIG. These results indicate that IVIG infusions may be preferable to high-dose corticosteroids as initial treatment for children with ITP.

Split-receptors in the tachykinin neurokinin-1 system--mutational analysis of intracellular loop 3

Several membrane proteins have been functionally expressed from non-covalently coupled, contiguous segments especially with the split-site located between natural domains. Experiments using such 'split-proteins' were here performed in the tachykinin neurokinin-1 (NK1) receptor with co-expression of contiguous segments with split-sites positioned in various intracellular and extracellular loops. The construct where the split-site was located in intracellular loop 3 gave a reasonable expression level of substance-P-binding sites, i.e. 12% of wild-type expression. Of the other split-receptors tested, only the one with the split-site located just outside transmembrane (TM) segment-V gave any detectable substance P binding, which however only was 1% of the wild-type expression level. The construct with the split-site located in intracellular loop 3 bound all of the tested peptide agonists and non-peptide antagonists with normal affinity and was able to stimulate inositol phosphate turnover with a normal EC50 for substance P and an Emax according to the expression level. When intracellular loop 3 was either extended with 112 amino acid residues derived from the muscarine M2 receptor or, when major parts of the loop were deleted in the non-split NK1 receptor, the affinity for neither substance P nor for the prototype nonpeptide antagonist, CP96,345 was affected, yet an increase in EC50 for substance P was observed. Also in the split-receptor, most of intracellular loop 3 could be substituted or even deleted without affecting ligand affinity, although a decreased expression level was observed in constructs having major deletions. It is concluded, that the NK1 receptor is preferentially reconstituted by co-expression of a putative A-domain including TM-I-V and a B-domain including TM-VI and -VII. It is suggested that a number of rhodopsin-like 7TM receptors may function as two-domain structures based on the finding that a network of short loops has been highly conserved within each of the putative domains and, that these domains are separated by a relatively long and in respect of length poorly conserved loop, i.e. intracellular loop 3.

Neuro-acanthocytosis--a rare cause of chorea

Neuro-acanthocytosis is a rare neurological disorder characterised by stereotyped chorea, especially of the mouth, areflexia and acanthocytes seen in the peripheral blood. No cases have been described in the literature from South Africa. We report here a case of neuro-acanthocytosis seen in a black woman who presented to Johannesburg Hospital.

Renal CT after intravenous injection of nonionic dimeric or nonionic monomeric contrast media in healthy volunteers

PURPOSE

To establish and compare time-density curves of the aorta, vena cava and renal cortex, medulla and pelvis after injection of the nonionic dimer iodixanol or the nonionic monomer iopromide contrast media.

MATERIAL AND METHODS

In 36 healthy volunteers CT at the renal hilus was performed at regular intervals before and until 30 min after injection of 13.5 g I iodixanol or 15.0 g I iopromide. The density of the renal cortex, medulla, pelvis, aorta and inferior caval vein was measured.

RESULTS

With injection of the 10% lower iodine dose in the iodixanol group, the profiles of the CT time-density curves were similar for all regions except for the renal pelvis. For the renal pelvis, significantly higher density values were obtained for the iodixanol group up to 10 min after injection.

CONCLUSION

Although the present study shows that a lower iodine dose is needed for a dimeric compared to a monomeric nonionic contrast medium to obtain similar time-density curves, more studies are needed to establish the clinical importance of this for urography.

Engineering of metal-ion sites as distance constraints in structural and functional analysis of 7TM receptors

G-protein-coupled receptors with their seven transmembrane (7TM) segments constitute the largest superfamily of proteins known. Unfortunately, still only relatively low resolution structures derived from electron cryo-microscopy analysis of 2D crystals are available for these proteins. We have used artificially designed Zn(II) metal-ion binding sites to probe 7TM receptors structurally and functionally and to define some basic distance constraints for molecular modeling. In this way, the relative helical rotation and vertical translocation of transmembrane helices TM-II, TM-III, TM-V, and TM-VI of the tachykinin NK-1 receptor have been restricted. Collectively, these zinc sites constitute a basic network of distance constraints that limit the degrees of freedom of the interhelical contact faces in molecular models of 7TM receptors. The construction of artificially designed metal-ion sites is discussed also in the context of probes for conformational changes occurring during receptor activation.

Ultrasonographically guided fine-needle aspiration biopsy of intrathoracic tumors

PURPOSE

Evaluation of diagnostic accuracy and complication frequency at ultrasonographically guided fine-needle aspiration biopsy of intrathoracic tumors.

MATERIAL AND METHODS

A total of 134 ultrasonographically guided percutaneous fine-needle aspiration biopsies were performed on 128 patients with intrathoracic tumors abutting on the pleura. A cytologic diagnosis was obtained in 119 patients (93%).

RESULTS

In 83 patients, cytologic malignancy was found; in 34, benignity; and in 2, cellular atypia. A total of 117 diagnoses were correct and 2 diagnoses were false-positive. A malignancy subtyping based on the cytologic aspirates was made in 80 patients. In 40 (93%) of 43 histologically proven subtypes, the subtyping was correct. The complication frequency in terms of pneumothorax was 3.7%.

CONCLUSION

Ultrasonographically guided percutaneous fine-needle aspiration biopsy is a safe and reliable method of establishing the cytologic diagnosis of intrathoracic tumors.

Ultrasonographic in vitro examination of nonpalpable breast masses. A new method

Specimen radiology is necessary for ensuring successful surgical excision of nonpalpable, clinically occult breast masses discovered by mammography. However, occasionally nonpalpable lesions are only detected by sonography. A simple method of ultrasonographic in vitro identification of nonpalpable lesions invisible on specimen radiographs is presented.

Mediastinal staging of non-small-cell lung cancer: computed tomography and cervical mediastinoscopy

The exact indications for computed tomography (CT) of the thorax and mediastinoscopy (MS) in lung cancer still remain incompletely defined. The present study was designed to establish a standard approach to cervical MS for otolaryngologists, who in Denmark are traditionally involved in the staging of non-small-cell lung cancer (NSCLC). Sixty-four potentially operable patients with NSCLC underwent thoracic CT prior to bronchoscopy and cervical MS. Cervical MS alone established the histological diagnosis in 20% of the patients. In diagnosing lymph node metastases in the superior mediastinum, a criterion of 10 mm for abnormal enlargement resulted in an overall sensitivity and specificity of mediastinal CT of 81 and 84%, respectively, and the overall false-negative and false-positive rates appeared to be 10 and 29%, respectively. It could be demonstrated that mediastinal lymph nodes in patients with mediastinal metastases were significantly larger than mediastinal lymph nodes in patients without metastases. No clinicopathological characteristics could be identified to influence the accuracy of CT, except for the finding that the rate of false-negative mediastinal CT was significantly higher in patients with right-sided than in patients with left-sided lesions. It is concluded that because of the relatively low sensitivity and specificity of mediastinal CT, cervical MS remains essential in the evaluation of patients with presumed or verified NSCLC and that cervical MS, in experienced hands, is a safe and accurate procedure. For Danish otolaryngologists, the strategy of routine cervical MS, performed under general anaesthesia in the same stage as bronchoscopy, is advocated as a standard approach to mediastinal assessment for the staging of NSCLC. However, thoraco-abdominal CT is advocated for all patients with NSCLC, in whom operation is contemplated, as a supplementary investigation after other routine diagnostic and staging procedures, including cervical MS, have been carried out.

Mediastinal staging of lung cancer. Is mediastinoscopy still essential?

The significance of computed tomography of the thorax and mediastinoscopy in pretherapeutic mediastinal assessment for the staging of lung cancer remains controversial. The presents study was designed to establish a standard approach to cervical mediastinoscopy for otolaryngologists, who in Denmark traditionally are involved in the staging of non-small cell lung cancer. Sixty-four potentially operable patients with non-small cell lung cancer underwent thoracic computed tomography prior to bronchoscopy and cervical mediastinoscopy. Thirty-six of the 43 mediastinoscopically negative patients additionally underwent thoracotomy, which in 32 cases was considered curative. Mediastinoscopy alone established the lung cancer diagnosis in 20% of the patients. In diagnosing lymph node metastases in the superior mediastinum, a criterion of 10 mm for abnormal enlargement resulted in an overall sensitivity and specificity of mediastinal computed tomography of 72% and 85%, respectively, and the overall false-negative and false-positive rates appeared to be 18% and 25%, respectively. No clinicopathological characteristics could be identified that influenced the occurrence of mediastinal metastases or the accuracy of computed tomography. It is concluded that mediastinoscopy remains essential in the evaluation of patients with presumed or verified non-small cell lung cancer. For otolaryngologists, the strategy of routine cervical mediastinoscopy, performed under general anesthesia in the same procedure as bronchoscopy, is advocated as a standard approach to preoperative mediastinal assessment for the staging of non-small cell lung cancer.

Conversion of antagonist-binding site to metal-ion site in the tachykinin NK-1 receptor

Mutational analysis of the tachykinin NK-1 (refs 1-7), NK-2 (ref. 8) and angiotensin AT-1 (refs 9, 10) receptors indicates that non-peptide antagonists act through residues located between the seven transmembrane segments, whereas natural peptide agonists bind mainly to residues scattered in the exterior part of the receptor. The presumed contact points for the prototype NK-1 antagonist CP96,345 cluster on opposing faces of the outer portions of transmembrane helices V and VI (refs 1-5). Here we show that systematic introduction of histidyl residues at this antagonist-binding site in the human NK-1 receptor gradually converts it into a high-affinity metal-ion-binding site without affecting agonist binding. In a double mutant with histidine residues substituted at the top of transmembrane segments V and VI, respectively, Zn2+ inhibits binding of radiolabelled agonist peptide and efficiently blocks phosphoinositol turnover induced by substance P. We propose that Zn2+ and CP96,345 act as 'allosteric competitive' antagonists by stabilizing inactive conformations of the mutant and the wild-type receptor respectively. Introduction of metal-ion-binding sites could be used as a general tool in the structural and functional characterization of helix-helix interactions in G-protein-coupled receptors, as well as in other membrane proteins.

Definition of inseparably fused ventricular myocardium in thoracopagus: fetal echocardiographic utility and pathologic refinement

Correlative echocardiographic and pathological findings in a thoracopagus with conjoined hearts are reported. One twin had tricuspid atresia with discordant atrioventricular connections and concordant ventriculoarterial connections. The morphologic right ventricle was hypoplastic and there was a large muscular ventricular septal defect. The other twin had hypoplasia of the mitral valve anulus and left ventricle with double-outlet right ventricle and pulmonary valve atresia. The tricuspid valve was severely insufficient in part because of a large orifice and redundant, elongated leaflets with abnormal chordal attachments. The left ventricles of these two twins shared a perforated common "free wall" with at least two large defects allowing mixing of the circulations at that level. Not all anatomic details were established conclusively by fetal echocardiography; however, sufficient diagnostic information was obtained to support a decision not to aggressively resuscitate these twins after elective cesarean delivery at 31 weeks' gestation.

Idiopathic renal vein varicosities. Presentation of two cases and a brief review of the literature

Two cases of idiopathic peripelvic renal vein varicosities are reported. From a literature review the aethilogy, incidence, symptomatology, radiographic appearance and treatment of this lesion is elucidated. The importance of selective renal vein phlebography in the evaluation of unexplained hematuria and filing defects in the excretory urogram is illustrated.