The incremental yield of prenatal exome sequencing over chromosome microarray for congenital heart abnormalities: A systematic review and meta-analysis

OBJECTIVES

To determine the incremental yield of prenatal exome sequencing (PES) over standard testing in fetuses with an isolated congenital heart abnormality (CHA), CHA associated with extra-cardiac malformations (ECMs) and CHA dependent upon anatomical subclassification.

METHODS

A systematic review of the literature was performed using MEDLINE, EMBASE, Web of Science and grey literature January 2010-February 2023. Studies were selected if they included greater than 20 cases of prenatally diagnosed CHA when standard testing (QF-PCR/chromosome microarray/karyotype) was negative. Pooled incremental yield was determined. PROSPERO CRD 42022364747.

RESULTS

Overall, 21 studies, incorporating 1957 cases were included. The incremental yield of PES (causative pathogenic and likely pathogenic variants) over standard testing was 17.4% (95% CI, 13.5%-21.6%), 9.3% (95% CI, 6.6%-12.3%) and 35.9% (95% CI, 21.0%-52.3%) for all CHAs, isolated CHAs and CHAs associated with ECMs. The subgroup with the greatest yield was complex lesions/heterotaxy; 35.2% (95% CI 9.7%-65.3%). The most common syndrome was Kabuki syndrome (31/256, 12.1%) and most pathogenic variants occurred de novo and in autosomal dominant (monoallelic) disease causing genes (114/224, 50.9%).

CONCLUSION

The likelihood of a monogenic aetiology in fetuses with multi-system CHAs is high. Clinicians must consider the clinical utility of offering PES in selected isolated cardiac lesions.

Contrast-enhanced CT radiomics for preoperative prediction of stage in epithelial ovarian cancer: a multicenter study

BACKGROUND

Preoperative prediction of International Federation of Gynecology and Obstetrics (FIGO) stage in patients with epithelial ovarian cancer (EOC) is crucial for determining appropriate treatment strategy. This study aimed to explore the value of contrast-enhanced CT (CECT) radiomics in predicting preoperative FIGO staging of EOC, and to validate the stability of the model through an independent external dataset.

METHODS

A total of 201 EOC patients from three centers, divided into a training cohort (n = 106), internal (n = 46) and external (n = 49) validation cohorts. The least absolute shrinkage and selection operator (LASSO) regression algorithm was used for screening radiomics features. Five machine learning algorithms, namely logistic regression, support vector machine, random forest, light gradient boosting machine (LightGBM), and decision tree, were utilized in developing the radiomics model. The optimal performing algorithm was selected to establish the radiomics model, clinical model, and the combined model. The diagnostic performances of the models were evaluated through receiver operating characteristic analysis, and the comparison of the area under curves (AUCs) were conducted using the Delong test or F-test.

RESULTS

Seven optimal radiomics features were retained by the LASSO algorithm. The five radiomics models demonstrate that the LightGBM model exhibits notable prediction efficiency and robustness, as evidenced by AUCs of 0.83 in the training cohort, 0.80 in the internal validation cohort, and 0.68 in the external validation cohort. The multivariate logistic regression analysis indicated that carcinoma antigen 125 and tumor location were identified as independent predictors for the FIGO staging of EOC. The combined model exhibited best diagnostic efficiency, with AUCs of 0.95 in the training cohort, 0.83 in the internal validation cohort, and 0.79 in the external validation cohort. The F-test indicated that the combined model exhibited a significantly superior AUC value compared to the radiomics model in the training cohort (P < 0.001).

CONCLUSIONS

The combined model integrating clinical characteristics and radiomics features shows potential as a non-invasive adjunctive diagnostic modality for preoperative evaluation of the FIGO staging status of EOC, thereby facilitating clinical decision-making and enhancing patient outcomes.

The use of cardiac magnetic resonance in hypertrophic cardiomyopathy over the past 10 years [2013-2023]: a CiteSpace-based bibliometric analysis

Background

Hypertrophic cardiomyopathy (HCM) is a common genetic cardiac disorder characterized by the hypertrophy of a segment of the myocardium. Cardiac magnetic resonance (CMR) has been widely used in the assessment of HCM. However, no bibliometric assessment has been conducted on the progress of research in this field. This study thus aimed to examine the current state of research into the application of CMR in HCM and the hotspots and trends that have emerged in this field over the past decade.

Methods

A systematic search was conducted on the Web of Science regarding CMR in the assessment of HCM. The databases were searched from 2013 to June 2023. CiteSpace is an application that can be used to characterize the underlying knowledge of the scientific literature in a given field. We used it to analyze the relationship between publication year and country, institution, journal, author, bibliography, and keywords in the field of CMR for the assessment of HCM.

Results

A total of 1,427 articles were included in the analysis. In the assessment of HCM, the findings from the past decade have consistently demonstrated a progressive rise in the quantity of articles pertaining to CMR. The country with the largest number of publications was the United States [310], and the institution with the greatest number of publications was the University College London [45]. The analysis of keywords revealed the diagnosis and management of HCM with CMR to be the current research focus and emerging trend within this academic field.

Conclusions

This study used a novel approach to visually analyze the use of CMR in HCM assessment. The current research trajectory in CMR consists of the diagnosis and management of patients with HCM. Although most studies confirmed the indispensability of CMR in the assessment of HCM, larger-scale cohorts are still needed to more comprehensively evaluate the role of CMR in the differential diagnosis, pre- and post-treatment assessment, and long-term management of patients with HCM.

The predictive value of coronary microvascular dysfunction for left ventricular reverse remodelling in dilated cardiomyopathy

Aims

To evaluate the degree of coronary microvascular dysfunction (CMD) in dilated cardiomyopathy (DCM) patients by cardiac magnetic resonance (CMR) first-pass perfusion parameters and to examine the correlation between myocardial perfusion and left ventricle reverse remodelling (LVRR).

Methods

In this study, 94 DCM patients and 35 healthy controls matched for age and sex were included. Myocardial perfusion parameters, including upslope, time to maximum signal intensity (Timemax), maximum signal intensity (SImax), baseline signal intensity (SIbaseline), and the difference between maximum and baseline signal intensity (SImax-baseline) were measured. Additionally, left ventricular (LV) structure, function parameters, and late gadolinium enhancement (LGE) were also recorded. The parameters were compared between healthy controls and DCM patients. Univariable and multivariable logistic regression analyses were used to determine the predictors of LVRR.

Results

With a median follow-up period of 12 months [interquartile range (IQR), 8-13], 41 DCM patients (44%) achieved LVRR. Compared with healthy controls, DCM patients presented CMD with reduced upslope, SIbaseline, and increased Timemax (all p < 0.01). Timemax, SImax, and SImax-baseline were further decreased in LVRR than non-LVRR group (Timemax: 60.35 [IQR, 51.46-74.71] vs. 72.41 [IQR, 59.68-97.70], p = 0.017; SImax: 723.52 [IQR, 209.76-909.27] vs. 810.92 [IQR, 581.30-996.89], p = 0.049; SImax-baseline: 462.99 [IQR, 152.25-580.43] vs. 551.13 [IQR, 402.57-675.36], p = 0.038). In the analysis of multivariate logistic regression, Timemax [odds ratio (OR) 0.98; 95% confidence interval (CI) 0.95-1.00; p = 0.032)], heart rate (OR 1.04; 95% CI 1.01-1.08; p = 0.029), LV remodelling index (OR 1.73; 95% CI 1.06-3.00; p = 0.038) and LGE extent (OR 0.85; 95% CI 0.73-0.96; p = 0.021) were independent predictors of LVRR.

Conclusions

CMD could be found in DCM patients and was more impaired in patients with non-LVRR than LVRR patients. Timemax at baseline was an independent predictor of LVRR in DCM.

The potential predictive value of cardiac mechanics for left ventricular reverse remodelling in dilated cardiomyopathy

AIMS

Left ventricular reverse remodelling (LVRR) is an important objective of optimal medical management for dilated cardiomyopathy (DCM) patients, as it is associated with favourable long-term outcomes. Cardiac magnetic resonance (CMR) can comprehensively assess cardiac structure and function. We aimed to assess the CMR parameters at baseline and investigate independent variables to predict LVRR in DCM patients.

METHODS AND RESULTS

Nighty-eight initially diagnosed DCM patients who underwent CMR and echocardiography examinations at baseline were included. CMR parameters and feature tracking (FT) based left ventricular (LV) global strain (nStrain) and nStrain indexed to LV cardiac mass index (rStrain) were measured. The predictors of LVRR were determined by multivariate logistic regression analyses. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic performance of CMR parameters and were compared by the DeLong test. At a median follow-up time of 9 [interquartile range, 7-12] months, 35 DCM patients (36%) achieved LVRR. The patients with LVRR had lower LV volume, mass, LGE extent and stroke volume index (LVSVi) and higher left ventricular remodelling index (LVRI), nStrains, rStrains, and peak systolic strain rate (PSSR) in the longitudinal direction and rStrains in the circumferential direction at baseline (all P < 0.05). In the multivariate logistic regression analyses, LVRI [per SD, odds ratio (OR) 1.79; 95% confidence interval (CI) 1.08-2.98; P = 0.024] and the ratio of global longitudinal peak strain (rGLPS) (per SD, OR 1.88; 95% CI 1.18-3.01; P = 0.008) were independent predictors of LVRR. The combination of LVSVi, LVRI, and rGLPS had a greater area under the curve (AUC) than the combination of LVSVi and LVRI (0.75 vs. 0.68), but not significantly (P = 0.09).

CONCLUSIONS

Patients with LVRR had a lower LV volume index, lower LVSV index, lower LGE extent, higher LVRI, and preserved myocardial deformation in the longitudinal direction at baseline. LVRI and rGLPS at baseline were independent determinants of LVRR.

The application of radiology for dilated cardiomyopathy diagnosis, treatment, and prognosis prediction: a bibliometric analysis

Background

Radiology plays a highly crucial role in the diagnosis, treatment, and prognosis prediction of dilated cardiomyopathy (DCM). Related research has increased rapidly over the past few years, but systematic analyses are lacking. This study thus aimed to provide a reference for further research by analyzing the knowledge field, development trends, and research hotspots of radiology in DCM using bibliometric methods.

Methods

Articles on the radiology of DCM published between 2002 and 2021 in the Web of Science Core Collection database (WoSCCd) were searched and analyzed. Data were retrieved and analyzed using CiteSpace V, VOSviewer, and Scimago Graphic software, and included the name, research institution, and nationality of authors; journals of publication; and the number of citations.

Results

A total of 4,257 articles were identified on radiology of DCM from WoSCCd. The number of articles published in this field has grown steadily from 2002 to 2021 and is expected to reach 392 annually by 2024. According to subfields, the number of papers published in cardiac magnetic resonance field increased steadily. The authors from the United States published the most (1,364 articles, 32.04%) articles. The author with the most articles published was Bax JJ (54 articles, 1.27%) from Leiden University Medical Center. The most cited article was titled "2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure", with 138 citations. Citation-based clustering showed that arrhythmogenic cardiomyopathy, T1 mapping, and endomyocardial biopsy are the current hots pots for research in DCM radiology. The most frequently occurring keyword was "dilated cardiomyopathy". The keyword-based clusters mainly included "late gadolinium enhancement", "congestive heart failure", "cardiovascular magnetic resonance", "sudden cardiac death", "ventricular arrhythmia", and "cardiac resynchronization therapy".

Conclusions

The United States and Northern Europe are the most influential countries in research on DCM radiology, with many leading distinguished research institutions. The current research hots pots are myocardial fibrosis, risk stratification of ventricular arrhythmia, the prognosis of cardiac resynchronization therapy (CRT) treatment, and subtype classification of DCM.

Periplasmic stress contributes to a tradeoff between protein secretion and cell growth in E. Coli Nissile

Maximizing protein secretion is an important target in the design of engineered living systems. In this paper, we characterize a tradeoff between cell growth and per cell protein secretion in the curli biofilm secretion system of E Coli Nissile 1917. Initial characterization using 24-hour continuous growth and protein production monitoring confirms decreased growth rates at high induction leading to a local maximum in total protein production at intermediate induction. Propidium iodide staining at the endpoint indicates that cellular death is a dominant cause of growth reduction. Assaying variants with combinatorial constructs of inner and outer membrane secretion tags, we find that diminished growth at high production is specific to secretory variants associated with accumulation of protein containing the outer membrane transport tag in the periplasmic space. RNA sequencing experiments indicate upregulation of known periplasmic stress response genes in the highly secreting variant, further implicating periplasmic stress in the growth-secretion tradeoff. Overall, these results motivate additional strategies for optimizing total protein production and longevity of secretory engineered living systems.

Efficieny of Phage Intervention Against Salmonella in Meat and Poultry Processing

ObjectivesPathogen Reduction, Hazard Analysis, and Critical Control Point systems final rule mandates establishments to seek and adopt antimicrobial interventions that can help in reducing the prevalence and most probable number of Salmonella in their meat and poultry products. Bacteriophages can aid in this challenge, as they can invade and kill specific target pathogenic bacteria on food products. Effective kill by phages relies on the appropriate phage application technique. Correct dose, good distribution on the food surface area, and adequate dwell time are key factors which influence phage-bacteria contact and thereby phage efficacy. This study determined the efficacy of a commercially available phage product, PhageGuard S consisting of 2 phages, FO1a, and S16. Different pick up levels, blend and hold times (chosen based on regulatory restriction and process limitations), as well as spray versus dip treatment methods were tested.Materials and MethodsOvernight culture streptomycin resistant Salmonella enterica enterica Enteritidis C (Se13) was diluted and inoculated at a concentration of 2×104 CFU/cm2 or CFU/g on parts of chicken fillet and held for 10 min for bacterial attachment (duplicate samples per time point). Subsequently, contaminated parts were spray treated with one phage concentration (108 Plaque Forming Units/g) at 0.5%, 1% or 3% pick up (v/w) or water (control) and blended for 5, 10, and 20 min before immediate grinding and retrieval of bacteria (latter blend time sample was held for 24 h before grind). Another set of contaminated fillet parts were treated by dipping in 5% phage solution (at 1% pick up, 108 PFU/g) and held for 1, 5, 10, and 20 min, and 1 and 24 h at 40°F (4°C) before retrieval of bacteria. Enumeration of bacteria was done on selective agar plates and reductions were calculated relative to water treated control.ResultsThe application of phages 108 PFU/g via spray on chicken parts at 3% pick up and 20 min blend time resulted in 0.9 log10 CFU/g log reduction of Salmonella. Additional hold time of 24 h before grind resulted in 1.1- 1.2 log10 CFU/g kill at lower and higher pick up of 0.5% and 3%. Dip treatment resulted higher Salmonella reduction of 1.2 log10 CFU/cm2 within 5 min of 108 PFU/cm2 phage application and up to 2.3 log10 CFU/cm2 log10 reduction when held for 24 h. Overall, the spray technique, showed a dose response effect where increasing pick up and blend time resulted in an increasing Salmonella kill in ground product. However, the dip technique resulted in more effective Salmonella kill in shorter dwell time. All values are mean value of two individual experiments.ConclusionThe above results indicate that the commercially available phage solution, PhageGuard S, either via spray or dip method reduces Salmonella contamination on meat and poultry parts by 1.2 to 2.3 log10, respectively. Thereby is an effective intervention in reducing risks and allowing for increase in consumer safety. Dip technique works better than spray due to better distribution on meat surface. Longer hold and/or blend time after phage treatment results in more kill.

Converse Smith-Martin cell cycle kinetics by transformed B lymphocytes

Recent studies using direct live cell imaging have reported that individual B lymphocytes have correlated transit times between their G1 and S/G2/M phases. This finding is in contradiction with the influential model of Smith and Martin that assumed the bulk of the total cell cycle time variation arises in the G1 phase of the cell cycle with little contributed by the S/G2/M phase. Here we extend these studies to examine the relation between cell cycle phase lengths in two B lymphoma cell lines. We report that transformed B lymphoma cells undergo a short G1 period that displays little correlation with the time taken for the subsequent S/G2/M phase. Consequently, the bulk of the variation noted for total division times within a population is found in the S/G2/M phases and not the G1 phase. Models that reverse the expected source of variation and assume a single deterministic time in G1 followed by a lag + exponential distribution for S/G2/M fit the data well. These models can be improved further by adopting two sequential distributions or by using the stretched lognormal model developed for primary lymphocytes. We propose that shortening of G1 transit times and uncoupling from other cell cycle phases may be a hallmark of lymphocyte transformation that could serve as an observable phenotypic marker of cancer evolution.

Short- and long-term clinical outcomes of use of beta-interferon or glatiramer acetate for people with clinically isolated syndrome: a systematic review of randomised controlled trials and network meta-analysis

Background

Beta-interferon (IFN-β) and glatiramer acetate (GA) have been evaluated in people with clinically isolated syndrome (CIS) with the aim to delay a second clinical attack and a diagnosis of clinically definite multiple sclerosis (CDMS). We systematically reviewed trials evaluating the short- and long-term clinical effectiveness of these drugs in CIS.

Methods

We searched multiple electronic databases. We selected randomised controlled studies (RCTs) conducted in CIS patients and where the interventions were IFN-β and GA. Main outcomes were time to CDMS, and discontinuation due to adverse events (AE). We compared interventions using random-effect network meta-analyses (NMA). We also reported outcomes from long-term open-label extension (OLE) studies.

Results

We identified five primary studies. Four had open-label extensions following double-blind periods comparing outcomes between early vs delayed DMT. Short-term clinical results (double-blind period) showed that all drugs delayed CDMS compared to placebo. Indirect comparisons did not suggest superiority of any one active drug over another. We could not undertake a NMA for discontinuation due to AE. Long-term clinical results (OLE studies) showed that the risk of developing CDMS was consistently reduced across studies after early DMT treatment compared to delayed DMT (HR = 0.64, 95% CI 0.55, 0.74). No data supported the benefit of DMTs in reducing the time to, and magnitude of, disability progression.

Conclusions

Meta-analyses confirmed that IFN-β and GA delay time to CDMS compared to placebo. In the absence of evidence that early DMTs can reduce disability progression, future research is needed to better identify patients most likely to benefit from long-term DMTs.

Electronic supplementary material

The online version of this article (10.1007/s00415-018-8752-8) contains supplementary material, which is available to authorized users.

The role of the endometrial receptivity array (ERA) in patients who have failed euploid embryo transfers

PURPOSE

Endometrial receptivity issues represent a potential source of implantation failure. The aim of this study was to document our experience with the endometrial receptivity array (ERA) among patients with a history of euploid blastocyst implantation failure. We investigated whether the contribution of the endometrial factor could be identified with the ERA test and if actionable results can lead to improved outcomes.

METHODS

A retrospective review was performed for 88 patients who underwent ERA testing between 2014 and 2017. Reproductive outcomes were compared for patients undergoing frozen embryo transfer (FET) using a standard progesterone protocol versus those with non-receptive results by ERA and subsequent FET according to a personalized embryo transfer (pET) protocol.

RESULTS

Of patients with at least one previously failed euploid FET, 22.5% had a displaced WOI diagnosed by ERA and qualified for pET. After pET, we found that implantation and ongoing pregnancy rates were higher (73.7 vs. 54.2% and 63.2 vs. 41.7%, respectively) compared to patients without pET, although differences were not statistically significant.

CONCLUSIONS

Our experience demonstrates that a significant proportion of patients with a history of implantation failure of a euploid embryo have a displaced WOI as detected by the ERA. For these patients, pET using a modified progesterone protocol may improve the outcomes of subsequent euploid FET. Larger randomized studies are required to validate these results.

SNHG and UCA1 as prognostic molecular biomarkers in hepatocellular carcinoma: recent research and meta-analysis

INTRODUCTION

The latest studies have shown that the long non-coding RNAs seemed to be qualified markers of cancer. So we sought to assess the prognostic value of SNHG and UCA1 as predictive markers of patients with hepatocellular carcinoma (HCC).

EVIDENCE ACQUISITION

Relevant literatures were collected in PubMed and Embase. Measuring the expression of specific SNHG or UCA1 in tissue or serum and studying their association with survival outcome. Survival outcome was further explored considering the hazard ratio (HR) with confidence interval (CI).

EVIDENCE SYNTHESIS

We found that patients with higher expression of pooled SNHG/UCA1 had significant poor overall survival (HR 1.74; 95% CI: 1.05-2.89), and also significant for only SNHG (HR 2.05; 95% CI: 1.06-3.96). Over-expression of UCA1 may predict meaningless overall survival (HR 1.31; 95% CI: 0.57-3.03; P=0.53).

CONCLUSIONS

Our meta-analysis demonstrated that SNHG and UCA1 may serve as prognostic biomarkers for HCC prognosis.

Is congenital pulmonary airway malformation really a rare disease? Result of a prospective registry with universal antenatal screening program

BACKGROUND

Congenital pulmonary airway malformation (CPAM) is an increasingly recognized disease with potential mortality. Owing to limited published studies, the true incidence is yet to be determined. We carried out this prospective study with the aim to estimate its true incidence on a population basis.

METHODS

An antenatal ultrasonography program was implemented since 2009. Fetuses with suspected intra-thoracic lesions were monitored by regular follow-ups. Antenatal course, postnatal outcomes, and other demographics were compared to those of patients with CPAM in the previous decades (1989-2008). The incidence of CPAM was calculated in different periods.

RESULTS

66 CPAM patients were identified between 2009 and 2014 with 62 patients being detected by antenatal scan. In contrast, 45 patients were identified between 1989 and 2008 with 27 patients being detected antenatally. The incidence rate during the past and recent period was estimated as ~1 in 27,400 and ~1 in 7200 live births, respectively (p = 0.024).

CONCLUSION

With increasing awareness of clinicians and the universal use of latest ultrasound technology, it is likely that more CPAM cases will be detected in the future. Here, we presented our best estimated incidence rate of CPAM, yet only a larger scale study can reveal its true incidence.

Comparative evaluation of performance measures for shading correction in time-lapse fluorescence microscopy

Time-lapse fluorescence microscopy is a valuable technology in cell biology, but it suffers from the inherent problem of intensity inhomogeneity due to uneven illumination or camera nonlinearity, known as shading artefacts. This will lead to inaccurate estimates of single-cell features such as average and total intensity. Numerous shading correction methods have been proposed to remove this effect. In order to compare the performance of different methods, many quantitative performance measures have been developed. However, there is little discussion about which performance measure should be generally applied for evaluation on real data, where the ground truth is absent. In this paper, the state-of-the-art shading correction methods and performance evaluation methods are reviewed. We implement 10 popular shading correction methods on two artificial datasets and four real ones. In order to make an objective comparison between those methods, we employ a number of quantitative performance measures. Extensive validation demonstrates that the coefficient of joint variation (CJV) is the most applicable measure in time-lapse fluorescence images. Based on this measure, we have proposed a novel shading correction method that performs better compared to well-established methods for a range of real data tested.

T-cell stimuli independently sum to regulate an inherited clonal division fate

In the presence of antigen and costimulation, T cells undergo a characteristic response of expansion, cessation and contraction. Previous studies have revealed that population-level reproducibility is a consequence of multiple clones exhibiting considerable disparity in burst size, highlighting the requirement for single-cell information in understanding T-cell fate regulation. Here we show that individual T-cell clones resulting from controlled stimulation in vitro are strongly lineage imprinted with highly correlated expansion fates. Progeny from clonal families cease dividing in the same or adjacent generations, with inter-clonal variation producing burst-size diversity. The effects of costimulatory signals on individual clones sum together with stochastic independence; therefore, the net effect across multiple clones produces consistent, but heterogeneous population responses. These data demonstrate that substantial clonal heterogeneity arises through differences in experience of clonal progenitors, either through stochastic antigen interaction or by differences in initial receptor sensitivities.

Why do populations of highly similar T cells have heterogeneous division destinies in response to antigenic stimulus? Here the authors develop a multiplex-dye assay and a mathematical framework to test clonal heterogeneity and show distinction in division destiny is a result of inter-clonal variability as lineage imprinting ensures clones share similar proliferation fates.

Automated and semi-automated cell tracking: addressing portability challenges

Cell tracking is a key task in the high-throughput quantitative study of important biological processes, such as immune system regulation and neurogenesis. Variability in cell density and dynamics in different videos, hampers portability of existing trackers across videos. We address these potability challenges in order to develop a portable cell tracking algorithm. Our algorithm can handle noise in cell segmentation as well as divisions and deaths of cells. We also propose a parameter-free variation of our tracker. In the tracker, we employ a novel method for recovering the distribution of cell displacements. Further, we present a mathematically justified procedure for determining the gating distance in relation to tracking performance. For the range of real videos tested, our tracker correctly recovers on average 96% of cell moves, and outperforms an advanced probabilistic tracker when the cell detection quality is high. The scalability of our tracker was tested on synthetic videos with up to 200 cells per frame. For more challenging tracking conditions, we propose a novel semi-automated framework that can increase the ratio of correctly recovered tracks by 12%, through selective manual inspection of only 10% of all frames in a video.

'An artefact gone awry': identification of the first case of nemaline myopathy by Dr R.D.K. Reye

In 1963, Shy et al. (Brain 1963;86:793-810) and Conen et al. (Can Med Assoc J 1963;89:983-986) published the first description of a novel myopathy characterized by the aggregation of rods (nemaline bodies) in the muscle fibres. This disorder was subsequently known as nemaline myopathy. Dr Douglas Reye, an Australian pathologist, described a patient with 'rod myopathy' five years earlier, in 1958. Here we present Dr Reye's original description of nemaline myopathy, and details of the 'second opinion' which concluded that the rod were a 'processing artifact', so that the case was never published. Detailed histological and immunocytochemical studies of this original case demonstrate the typical features of nemaline myopathy, and a mutation in skeletal muscle alpha-actin has recently been identified in this patient. Not only was Dr Reye the first to use the term 'rod' in relation to muscle disease, he also made observations that are relevant to the pathogenesis of nemaline myopathy.

The effect of dietary restriction and menstrual cycle on excess post-exercise oxygen consumption (EPOC) in young women

The purpose of this study was to evaluate the effect of acute dietary restriction on excess post-exercise oxygen consumption (EPOC) in young women at two different phases of the menstrual cycle. Five young sedentary women (age 21-22 years) participated in this study. Each subject visited the laboratory eight times for measurement of EPOC. They performed cycle ergometer exercise for 60 min at a work rate corresponding to approximately 70% of VO2max under each four different conditions (i.e. standard diet/follicular phase (SF), standard diet/luteal phase (SL), restricted diet/follicular phase (RF) and restricted diet/luteal phase (RL)). The exercise was performed in the morning and VO2 was measured for the last 15 min of each hour for 7 h after the exercise. As a control, VO2 was also measured with an identical time schedule under the same four conditions but without exercise. EPOC was calculated as the difference of the VO2-time integral for 7 h between the exercise and control trial days in each of the four conditions (i.e. SL, SF, RL and RF). The diet was precisely controlled during 2 days (i.e. the test day and the day preceding it). The standard diet was 1600 kcal day-1 and the restricted diet was half of the standard diet. A two-way (dietary and menstrual cycle factors) ANOVA indicated that EPOC was significantly affected only by the dietary factor. The dietary restriction decreased EPOC compared to the standard dietary condition (SF 8.6 +/- 2.1, RF 5.3 +/- 1.6, SL 8.9 +/- 4.8, RL 4.0 +/- 1.2 l). These data indicate that for young sedentary women, EPOC is significantly lowered by prior acute dietary restriction but is not influenced by different phases of the menstrual cycle.

Respiratory chain complex III [correction of complex] in deficiency with pruritus: a novel vitamin responsive clinical feature

We report a child with an isolated complex III respiratory chain deficiency and global developmental delay who had severe pruritus with elevated plasma bile acid levels. A liver biopsy showed micronodular cirrhosis, and enzymologic evaluation demonstrated an isolated complex III deficiency in both liver and muscle. His pruritus improved and serum bile acid levels decreased after treatment with menadione and vitamin C.

Combined morphological and interphase fluorescence in situ hybridization study in multiple myeloma of Chinese patients

To gain insight into the real incidence of the numeric chromosomal aberrations and the cell lineage involvement of the neoplastic process in multiple myeloma (MM), we examined 18 Chinese MM patients by May-Grunwald-Giemsa (MGG) staining and fluorescence in situ hybridization using three DNA centromeric probes specific for chromosomes 3, 7, and 9. In this investigation, cytogenetic abnormalities were detected in plasma cells (PCs), myeloid cells (MCs), and lymphoid cells (LCs) in all of the MM patients studied. This is the first demonstration of the cytogenetic aberration involved in the myeloid series. Furthermore, the MCs and PCs of 16 MM patients had the same aneuploidies in one or more of the chromosomes analyzed. These data suggest that the neoplastic transformation of MM may occur early in the hematopoietic development. Chromosomal aberrations involving mainly subclones and considerable cellular heterogeneity with gain of a variety of copy numbers of the same chromosome were demonstrated within PCs, which may possibly be the result of an underlying defect of PCs in the control of their number of chromosomes. Whereas PCs showed evidence suggestive of increased polyploidization, MCs and LCs, which exhibited similar chromosomal patterns as the former, rarely did. Thus, the clonal evolution from LC to PC, if that happens in MM, is characterized by chromosomal instability favoring growth of tumor cells with polysomies and polyploidies.

Tl-201 positive, Ga-67 negative hepatoblastoma: a case report of a 12-year-old boy

Hepatoblastoma is a primary liver neoplasm in which prompt diagnosis and resection are critical to long-term survival. Nuclear scintigraphy plays an important role in the characterization of hepatic masses. The authors present an unusual case of hepatoblastoma in a 12-year-old boy in whom Ga-67 scintigraphy and serum alpha-fetoprotein were negative. Positive Tl-201 scintigraphy pointed toward the true malignant nature of the mass and should be considered in the investigation of hepatic masses in childhood.

Human papillomavirus and host variables as predictors of clinical course in patients with juvenile-onset recurrent respiratory papillomatosis

This study provides the first systematic evaluation of papillomavirus type and viral mutation occurring during the course of juvenile-onset recurrent respiratory papillomatosis. One hundred ninety-nine consecutive papillomas excised from 47 children between 1981 and 1996 at The New Children's Hospital in Sydney, Australia, were tested for human papillomavirus (HPV) DNA by PCR. PCR products from the viral upstream regulatory region (URR) enhancer were sequenced, and variation was related to clinical variables. Forty-four of the 47 children had HPV-induced papillomas, with type 11 accounting for 24 (55%) and type 6 accounting for 19 (43%); one (2%) was positive for either type 6 or 11. Overall, 183 (98%) of the 186 samples with amplifiable DNA were HPV positive. There was no change in HPV type over time and no statistically significant association between HPV type and disease aggressiveness. One novel, large-scale URR duplication was identified in an HPV type 11 isolate in the last of a series of six papillomas examined and the first from the bronchus. However, the duplication was not found in HPV type 11 isolates from the associated pulmonary carcinoma and its metastases in other organs. Three of 14 URR point mutations coincided with transcription factor binding sites, but there were no obvious associations with clinical course. Chi-square and multiple linear regression analyses of clinicopathological variables revealed early age at diagnosis (less than 4 years) as an independent predictor of aggressive disease (P < 0.001). A bimodal distribution of the age at diagnosis was noted, with peaks at 2 and 11 years of age.

Functional diffusive/convective interaction determining maximal oxygen uptake in humans: its modeling perspective

In this short review, the frame of current understandings concerning what determines the upper limit of oxygen flow from the ambient air to the muscular mitochondria during maximal dynamic exercise in humans (i.e., VO2max), was summarized mainly from its modeling perspective. Several models and experimental evidences which appeared repeatedly in the recent debates regarding the factors limiting VO2max, were adopted and criticized. In conclusion, VO2max is determined in particular by the integrated interaction between the diffusive and convective factors both to lung O2-loading and muscular O2-unloading in the pathway for O2 flow, although all experimental observations cannot be satisfactorily explained at the present time.

Benign juvenile xanthogranuloma of the larynx

Benign juvenile xanthogranuloma is a normolipaemic, self-limiting condition usually presenting with cutaneous, orbital or occasionally with visceral lesions. It is one type of histiocytosis, a term referring to a group of non-inflammatory, proliferative disorders of the monocyte/macrophage and dendritic cell systems [7]. We report a case of benign juvenile xanthogranuloma occurring in the larynx, a location not previously described.

[Fetal circulation in relation to various maternal body positions]

To determine the possible effect of various maternal body position on feto-maternal circulation, we performed Doppler examinations on 50 women at different stages between the 27th and 40th week of normal pregnancy. Flow velocity waveforms of the umbilical artery, fetal descending aorta, and maternal uterine artery were recorded by pulsed Doppler scanner equipped with a 3.5MHz transducer (ALOKA SSD 680). The resistance index (RI) was calculated with the patient lying initially in the supine position, then 15 minutes later, in the lateral recumbent position. Maternal blood pressure, placental site, and fetal position were also assessed for possible relationship with the maternal position reflected by the resistance indices. The following results were obtained: (1) a negative correlation was observed between gestational period and umbilical artery flow velocity (r = -0.404, P < 0.05). (2) although up to the 37th week no outstanding difference was noted in the effect of maternal position on the flow velocity of the uterine and umbilical artery, from weeks 37 to 40, the resistance indices recorded in the supine position were significantly higher than those associated with the lateral recumbent position (P < 0.05). In the lateral recumbent position. Flow velocity of the umbilical artery was consistently in close correlation with that of the uterine artery. However maternal position had no bearing on the flow velocity in the fetal descending aorta; (3) no significant relationship was indicated between the flow velocity of the umbilical artery and blood pressure, placental site or fetal position.(ABSTRACT TRUNCATED AT 250 WORDS)

Prenatal diagnosis and post-mortem study of a fetus with mosaic trisomy 14 due to a dic(14)(p11)

Amniocentesis at 17 weeks' gestation revealed a mosaic karyotype--46,XX/46,XX,-14,+dic(14)(p11). No abnormalities were detected on ultrasound. Growth and placentation were normal. The fetus was examined after termination of pregnancy and micrognathia and pulmonary hyperlobation were the only abnormalities detected. Several tissues were set up for cytogenetics, including fetal skin, kidney, ovary, and placenta. The diagnosis was confirmed by these studies. The level of mosaicism varied between tissues, with the trisomy 14 cell line highest in amniotic fluid.

Hemiplegia due to posterior cerebral artery occlusion

BACKGROUND

Hemiplegia is a rare manifestation of posterior cerebral artery occlusion. The acute clinical picture may be difficult to differentiate from occlusion of the middle cerebral artery. A mechanism for the hemiplegia has not been conclusively determined.

CASE DESCRIPTION

We describe a patient with hemiplegia secondary to posterior cerebral artery occlusion by an embolized fragment of a prosthetic valve. Computed tomographic scan showed the foreign body just distal to the origin of the posterior cerebral artery with infarction of its vascular territory. These findings were later confirmed at autopsy. There was no radiological or autopsy evidence of involvement of the other cerebral arteries or their territories.

CONCLUSIONS

The patient provides further evidence that occlusion of the posterior cerebral artery just distal to its junction with the posterior communicating artery may produce contralateral hemiplegia without oculomotor nerve nucleus involvement.

Rare malignant mid-femoral tumours in the first decade of life. Report of three cases with short literature review

The most common femoral shaft tumours in children are eosinophilic granuloma and Ewing's sarcoma. Three children in the first decade of life with rare femoral shaft tumours are reported. There was one osteosarcoma and two chondrosarcomas. Radiographic differential diagnosis of the femoral shaft tumours and microscopic diagnostic difficulties of chondrosarcoma are discussed.

Case report 684. Infantile myofibromatosis

A 4-year-old boy presented with a mass in the left groin. Radiographic examination demonstrated that the soft-tissue mass contained calcification and was encroaching on the left femur. The pre-biopsy clinico-radiographic diagnosis was that of some sort of sarcoma. The pathological findings identified the mass as infantile myofibromatosis. This case serves to stress the need for greater caution in the clinico-radiographic diagnosis of soft-tissue tumors.

Giant centrifugal miliaria profunda

A 4-month-old developed rapidly enlarging, white plaques up to several centimeters in diameter in areas where occlusive tape had been applied, almost all on the sites of venous or arterial punctures. Microscopy demonstrated the features of miliaria profunda, with sweat duct occlusion and evidence of extravasation of sweat into the dermis. This clinical entity has not been described previously, and we suggest the name giant centrifugal miliaria profunda.

Gastric heterotopia causing airway obstruction

Two infants are reported each with a mass of heterotopic gastric tissue in the hypopharynx causing airway obstruction. Endoscopic laser removal of the tumours proved a satisfactory method of treatment. Gastric heterotopia in the head and neck region is rare but should be considered as a cause of stridor in infants.

Heterotropic brain tissue presenting as bald cysts with a collar of hypertrophic hair. The 'hair collar' sign

We report the cases of two children who were each noted at birth to have a single bald compressible nodule on the scalp that was surrounded by a collar of hypertrophic hair. One of the mothers had taken doxylamine succinate during pregnancy. Extensive investigations and, finally, surgery revealed that the lesions were heterotropic brain tissue without connection to the brain. Encephaloceles may also have a "hair collar." The presence of a hair collar around any cutaneous lesion should alert the clinician to the possibility of a neuroectodermal defect. All procedures on these lesions should be delayed until appropriate investigations have excluded any connection with the underlying nervous system.

Intrauterine dwarfism, peculiar facies and thin bones with multiple fractures--a new syndrome

Three newborns with thin ribs and thin long bones with multiple fractures are reported. Whereas one patient presents a syndromic association of bone dysplasia and intrauterine dwarfism two other patients cannot be appropriately evaluated due to lack of basic clinical and pathologic data.

Amoebic meningitis also occurs in NSW

The clinical, pathological and laboratory findings of a 3-year-old boy with proven primary amoebic meningo-encephalitis are described. The EEG showed changes of acute cortical necrosis lateralised to one temporal lobe and was similar to that described with Herpes simplex encephalitis. CT scan findings indicated acute cortical inflammation and basal arachnoiditis. The disease should be suspected in the context of acute pyogenic meningitis when no organisms are isolated. Treatment with amphotericin-B, miconazole and rifampicin has been effective in previously reported patients.

Primary amoebic (Naegleria) meningoencephalitis

The computed tomographic (CT) appearance of a case of primary meningoencephalitis due to the free living amoeba Naegleria fowleri is presented. The cisterns around and above the midbrain and the subarachnoid spaces were obliterated on precontrast CT. Marked enhancement in these regions was seen after intravenous contrast medium administration. The sulci and adjacent grey matter were also strongly enhanced. The ventricular size was normal. Pathological findings were those of arachnoiditis and invasion of the leptomeninges and brain substance by amoebae, especially at the base of the brain and cerebellum.