Brain size evolution in pipefishes and seahorses: the role of feeding ecology, life history and sexual selection.

Brain size varies greatly at all taxonomic levels. Feeding ecology, life history and sexual selection have been proposed as key components in generating contemporary diversity in brain size across vertebrates. Analyses of brain size evolution have, however, been limited to lineages where males predominantly compete for mating and females choose mates. Here, we present the first original data set of brain sizes in pipefishes and seahorses (Syngnathidae) a group in which intense female mating competition occurs in many species. After controlling for the effect of shared ancestry and overall body size, brain size was positively correlated with relative snout length. Moreover, we found that females, on average, had 4.3% heavier brains than males and that polyandrous species demonstrated more pronounced (11.7%) female-biased brain size dimorphism. Our results suggest that adaptations for feeding on mobile prey items and sexual selection in females are important factors in brain size evolution of pipefishes and seahorses. Most importantly, our study supports the idea that sexual selection plays a major role in brain size evolution, regardless of on which sex sexual selection acts stronger.

Are we making good use of our public resources? The false-positive rate of screening by fundus photography for diabetic macular oedema.

INTRODUCTION: A large proportion of patients diagnosed with diabetic maculopathy using fundus photography and hence referred to specialist clinics following the current screening guidelines adopted in Hong Kong and United Kingdom are found to be false-positive, implying that they did not have macular oedema. This study aimed to evaluate the false-positive rate of diabetic maculopathy screening using the objective optical coherence tomography scan. METHODS: This was a cross-sectional observational study. Consecutive diabetic patients from the Hong Kong West Cluster Diabetic Retinopathy Screening Programme with fundus photographs graded R1M1 were recruited between October 2011 and June 2013. Spectral-domain optical coherence tomography imaging was performed. Central macular thickness of ≥300 µm and/or the presence of optical coherence tomography signs of diabetic macular oedema were used to define the presence of diabetic macular oedema. Patients with conditions other than diabetes that might affect macular thickness were excluded. The mean central macular thickness in various subgroups of R1M1 patients was calculated and the proportion of subjects with central macular thickness of ≥300 µm was used to assess the false-positive rate of this screening strategy. RESULTS: A total of 491 patients were recruited during the study period. Of the 352 who were eligible for analysis, 44.0%, 17.0%, and 38.9% were graded as M1 due to the presence of foveal 'haemorrhages', 'exudates', or 'haemorrhages and exudates', respectively. The mean (±standard deviation) central macular thickness was 265.1±55.4 µm. Only 13.4% (95% confidence interval, 9.8%-17.0%) of eyes had a central macular thickness of ≥300 µm, and 42.9% (95% confidence interval, 37.7%-48.1%) of eyes had at least one optical coherence tomography sign of diabetic macular oedema. For patients with retinal haemorrhages only, 9.0% (95% confidence interval, 4.5%-13.5%) had a central macular thickness of ≥300 µm; 23.2% (95% confidence interval, 16.6%-29.9%) had at least one optical coherence tomography sign of diabetic macular oedema. The false-positive rate of the current screening strategy for diabetic macular oedema was 86.6%. CONCLUSION: The high false-positive rate of the current diabetic macular oedema screening adopted by the United Kingdom and Hong Kong may lead to unnecessary psychological stress for patients and place a financial burden on the health care system. A better way of screening is urgently needed. Performing additional spectral-domain optical coherence tomography scans on selected patients fulfils this need.

AWARENESS, KNOWLEDGE LEVEL, AND MISCONCEPTIONS ABOUT SEXUALLY TRANSMITTED INFECTIONS AMONG SECONDARY SCHOOL STUDENTS IN BRUNEI DARUSSALAM.

Sexually transmitted infections (STI) remain an important public health issue globally, particularly among the young population. Despite being preventable and curable, STI continue to spread. Lack of access to treatment is an important factor in many developing and underdeveloped nations. Lack of awareness and knowledge is another important factor. This study assessed the awareness, knowledge, and misconceptions among secondary school students on STI. Overall, awareness was poor but better among male students and those in the Pure Science academic streaming. Similarly, the knowledge level of STI was also poor: low level (63.0%), moderate level (34.4%), and high level (2.6%). Male students (p=0.014) and Pure Science academic streaming students (p<0.001) scored better. There were misconceptions, but poor knowledge was predominant. Common sources of information were teachers, health professionals, Internet, parents and TV programs. Based on our study, more needs to be done to improve the awareness and knowledge level of STI, and detailed inclusion into the educational curriculum may be a consideration.

Automated otolith image classification with multiple views: an evaluation on Sciaenidae.

Combined multiple 2D views (proximal, anterior and ventral aspects) of the sagittal otolith are proposed here as a method to capture shape information for fish classification. Classification performance of single view compared with combined 2D views show improved classification accuracy of the latter, for nine species of Sciaenidae. The effects of shape description methods (shape indices, Procrustes analysis and elliptical Fourier analysis) on classification performance were evaluated. Procrustes analysis and elliptical Fourier analysis perform better than shape indices when single view is considered, but all perform equally well with combined views. A generic content-based image retrieval (CBIR) system that ranks dissimilarity (Procrustes distance) of otolith images was built to search query images without the need for detailed information of side (left or right), aspect (proximal or distal) and direction (positive or negative) of the otolith. Methods for the development of this automated classification system are discussed.

Sound production in the tiger-tail seahorse Hippocampus comes: Insights into the sound producing mechanisms.

Acoustic signals of the tiger-tail seahorse (Hippocampus comes) during feeding were studied using wavelet transform analysis. The seahorse "click" appears to be a compounded sound, comprising three acoustic components that likely come from two sound producing mechanisms. The click sound begins with a low-frequency precursor signal, followed by a sudden high-frequency spike that decays quickly, and a final, low-frequency sinusoidal component. The first two components can, respectively, be traced to the sliding movement and forceful knock between the supraorbital bone and coronet bone of the cranium, while the third one (purr) although appearing to be initiated here is produced elsewhere. The seahorse also produces a growling sound when under duress. Growling is accompanied by the highest recorded vibration at the cheek indicating another sound producing mechanism here. The purr has the same low frequency as the growl; both are likely produced by the same structural mechanism. However, growl and purr are triggered and produced under different conditions, suggesting that such "vocalization" may have significance in communication between seahorses.

Novel life-history data for threatened seahorses provide insight into fishery effects.

Life-history variables for three incidentally captured species of seahorse (Kellogg's seahorse Hippocampus kelloggi, the hedgehog seahorse Hippocampus spinosissimus and the three-spot seahorse Hippocampus trimaculatus) were established using specimens obtained from 33 fisheries landing sites in Peninsular Malaysia. When samples were pooled by species across the peninsula, sex ratios were not significantly different from unity, and height and mass relationships were significant for all species. For two of these species, height at physical maturity (HM ) was smaller than the height at which reproductive activity (HR ) commenced: H. spinosissimus (HM = 99·6 mm, HR = 123·2 mm) and H. trimaculatus (HM = 90·5 mm, HR = 121·8 mm). For H. kelloggi, HM could not be estimated as all individuals were physically mature, while HR = 167·4 mm. It appears that all three Hippocampus spp. were, on average, caught before reproducing; height at 50% capture (HC ) was ≥HM but ≤HR . The results from this study probe the effectiveness of assessment techniques for data-poor fisheries that rely heavily on estimates of length at maturity, especially if maturity is poorly defined. Findings also question the sustainability of H. trimaculatus catches in the south-west region of Peninsular Malaysia, where landed specimens had a notably smaller mean height (86·2 mm) and markedly skewed sex ratio (6% males) compared with samples from the south-east and north-west of the peninsula.

Synapsin II gene expression in the dorsolateral prefrontal cortex of brain specimens from patients with schizophrenia and bipolar disorder: effect of lifetime intake of antipsychotic drugs.

Synapsins are neuronal phosphoproteins crucial to regulating the processes required for normal neurotransmitter release. Synapsin II, in particular, has been implied as a candidate gene for schizophrenia. This study investigated synapsin II mRNA expression, using real-time reverse transcriptase-PCR, in coded dorsolateral prefrontal cortical samples provided by the Stanley Foundation Neuropathology Consortium. Synapsin IIa was decreased in patients with schizophrenia when compared with both healthy subjects and patients with bipolar disorder, whereas synapsin IIb was only significantly reduced in patients with schizophrenia when compared with healthy subjects but not in patients with bipolar disorder. Furthermore, lifetime antipsychotic drug use was positively associated with synapsin IIa expression in patients with schizophrenia. Results suggest that impairment of synaptic transmission by synapsin II reduction may contribute to dysregulated convergent molecular mechanisms, which result in aberrant neural circuits that characterize schizophrenia, while implicating involvement of synapsin II in therapeutic mechanisms of currently prescribed antipsychotic drugs.

MRI findings in Duane's ocular retraction syndrome.

AIM: To investigate the innervation pattern of extra-ocular muscles in patients with clinically diagnosed Duane's ocular retraction syndrome (DRS) using magnetic resonance imaging (MRI). MATERIALS AND METHODS: The study population consisted of 11 patients. Six patients had type I DRS (eight eyes), four patients had type II DRS (five eyes) and one patient had inverse DRS. Images were acquired using a Siemens 3 T MRI system. The type of DRS, corresponding innervation findings, and condition of the affected muscles were evaluated by two experienced neuroradiologists in consensus. RESULTS: All patients with clinically diagnosed DRS type I showed absence of the abducens nerve (CN6), hypoplasia of the superior oblique muscle (SOM), and aberrant innervation of lateral rectus muscle (LRM) by an extra branch of oculomotor nerve (CN3). All patients with type II DRS show dual-innervation of the LRM (by CN6 and an aberrant CN3 branch) and hypoplasia of SOM. The single patient with inverse DRS showed hypoplasia of CN3, the medial rectus muscle (MRM), the inferior rectus muscle (IRM), and the inferior oblique muscle (IOM). CONCLUSION: Each type of DRS has characteristic MRI appearances. Therefore, MRI is a useful diagnostic tool for the confirmation and classification of suspected cases of DRS.

Dysregulation of miR-31 and miR-375 expression is associated with clinical outcomes in oral carcinoma.

OBJECTIVES: To identify differentially expressed miRNA between oral squamous cell carcinoma (OSCC) and non-cancer (NC) and to associate these with clinico-pathological parameters. MATERIALS AND METHODS: miRNA microarray profiling was utilized to obtain the expression profile of miRNAs in four OSCC and four NC samples. The expression of miR-31 and miR-375 was further validated in 26 OSCC and three NC samples using real-time-PCR. The association between miRNA expression and clinico-pathological parameters was tested by univariate and multivariate analyses. RESULTS: Microarray profiling demonstrated that 15 and four miRNAs were up-regulated and down-regulated, respectively, in OSCC as compared with NC. miR-31 and miR-375 were validated as up- and down-regulated miRNAs, respectively. In univariate analyses, expression of miR-31 was significantly elevated in early stage, tumours with no metastatic nodes and those from the buccal mucosa. By contrast, low miR-375 expression was significantly associated with late stage disease, larger tumour size and the non-cohesive type of pattern of invasion in OSCC. The association between miR-31 expression with tumour staging and site and miR-375 with tumour staging remained significant in multivariate analyses. CONCLUSIONS: This study has identified 19 miRNAs significantly associated with OSCC, and expressions of miR-31 and miR-375 were significantly related with clinico-pathological parameters suggesting they could be important in driving oral tumourigenesis.

Ectopic inferior vena cava thrombus secondary to a tubo-ovarian abscess.

Inferior vena cava (IVC) thrombosis typically arises distally from a thrombophlebitic extension in the pelvis or the lower extremities. It may also occur from propagation of an ovarian vein thrombosis as a result of gynaecological disorders such as pelvic inflammatory disease, endometritis or from pelvic surgeries. In this report, we present an interesting case of a tubo-ovarian abscess with an ectopic IVC thrombus. The approach to management in such cases is also highlighted.

MRI for transformation of preserved organs and their pathologies into digital formats for medical education and creation of a virtual pathology museum. A pilot study.

AIM: To evaluate the feasibility of magnetic resonance imaging (MRI) for the transformation of preserved organs and their disease entities into digital formats for medical education and creation of a virtual museum. MATERIALS AND METHODS: MRI of selected 114 pathology specimen jars representing different organs and their diseases was performed using a 3 T MRI machine with two or more MRI sequences including three-dimensional (3D) T1-weighted (T1W), 3D-T2W, 3D-FLAIR (fluid attenuated inversion recovery), fat-water separation (DIXON), and gradient-recalled echo (GRE) sequences. Qualitative assessment of MRI for depiction of disease and internal anatomy was performed. Volume rendering was performed on commercially available workstations. The digital images, 3D models, and photographs of specimens were archived into a workstation serving as a virtual pathology museum. RESULTS: MRI was successfully performed on all specimens. The 3D-T1W and 3D-T2W sequences demonstrated the best contrast between normal and pathological tissues. The digital material is a useful aid for understanding disease by giving insights into internal structural changes not apparent on visual inspection alone. Volume rendering produced vivid 3D models with better contrast between normal tissue and diseased tissue compared to real specimens or their photographs in some cases. The digital library provides good illustration material for radiological-pathological correlation by enhancing pathological anatomy and information on nature and signal characteristics of tissues. In some specimens, the MRI appearance may be different from corresponding organ and disease in vivo due to dead tissue and changes induced by prolonged contact with preservative fluid. CONCLUSIONS: MRI of pathology specimens is feasible and provides excellent images for education and creating a virtual pathology museum that can serve as permanent record of digital material for self-directed learning, improving teaching aids, and radiological-pathological correlation.

Gastro-oesophageal reflux disorders among Nepalese residing in Southeast Asia.

INTRODUCTION: Gastro-oesophageal reflux disorders (GORD) are common in Western countries and has been reported to be increasing in the East. This study assessed the prevalence of GORD among the Nepalese residing in the Brunei Darussalam. METHODS: Nepalese residing in two areas were invited to participate in this cross sectional questionnaire study. GORD was considered to be present if there was any heartburn, regurgitation or both experienced at least monthly that were associated with impairment of quality of life measures. Overall, 304 out of 320 (female 68.4%) with completed questionnaire were available for analysis. RESULTS: Overall 45.1% had reported symptoms of gastroesophageal reflux: heartburn and regurgitation (21.4%), heartburn alone (9.2%) and regurgitations alone (14.5%). However, only 7.2% had GORD. GORD was significantly more common among women (p=0.005), being shorter in height (p=0.013), those with co morbid conditions (p=0.023) and previously had endoscopy (p=0.006). There were no difference in age, duration of residence, body mass index (kg/m2), alcohol intake, tobacco and supplements use (all p>0.05). GORD was also significantly associated with the presence of psychosomatic symptoms such as backache, depression, fatigue, headache and insomnia (all p<0.05). Subjects with GORD also experienced significantly more other upper gastrointestinal complaints such as nausea, vomiting, early satiety, post-prandial fullness, and abdominal bloating (all p<0.05). CONCLUSIONS: The prevalence of GORD among Nepalese residing in Brunei Darussalam was 7.2%. Certain subjects' profiles were associated with GORD and patients with GORD were likely to experience more psychosomatic and other gastrointestinal symptoms.

Noninvasive Monitoring of Radiation-Induced Salivary Gland Vascular Injury.

Xerostomia is a common side effect of radiation therapy (RT) in patients with head and neck cancer. However, limited information is available on the temporal dynamics of parenchymal and vascular changes in salivary glands following RT. To address this gap in knowledge, we conducted experimental studies in mice employing ultrasound (US) with coregistered photoacoustic imaging (PAI) to noninvasively assess the early and late changes in salivary gland size, structure, vascularity, and oxygenation dynamics following RT. Multiparametric US-PAI of salivary glands was performed in immune-deficient and immune-competent mice before and after RT along with correlative sialometry and ex vivo histologic-immunohistochemical validation. US revealed reduction in gland volume and an early increase in vascular resistance postradiation. This was accompanied by a reduction in glandular oxygen consumption on PAI. Imaging data correlated strongly with salivary secretion and histologic evidence of acinar damage. The magnitude and kinetics of radiation response were impacted by host immune status, with immunodeficient mice showing early and more pronounced vascular injury and DNA damage response compared to immunocompetent animals. Our findings demonstrate the ability of noninvasive US-PAI to monitor dynamic changes in salivary gland hemodynamics following radiation and highlight the impact of the host immune status on salivary gland radiation injury.

Genome-wide analysis of oral squamous cell carcinomas revealed over expression of ISG15, Nestin and WNT11.

BACKGROUND: Multistep pathways and mechanisms are involved in the development of oral cancer. Chromosomal alterations are one of such key mechanisms implicated oral carcinogenesis. Therefore, this study aims to determine the genomic copy number alterations (CNAs) in oral squamous cell carcinoma (OSCC) using array comparative genomic hybridization (aCGH) and in addition attempt to correlate CNAs with modified gene expression. MATERIALS AND METHODS: Genome-wide screening was performed on 15 OSCCs using high-density aCGH. On the basis of pathway analysis, three genes (ISG15, Nestin and WNT11) which mapped to CNA regions were selected for further evaluation of their mRNA expression using quantitative reverse transcriptase PCR (qRT-PCR). RESULTS: Copy number alterations were observed on multiple genomic regions, including amplifications on 1p, 3q, 5p, 6p, 7p, 8q, 9q, 11q, 12q, 16p, 18p and deletions on 3p, 7q, 8p, 11q, 19q and 20q. Among the three selected genes, ISG15 had the highest mRNA expression level with a 22.5-fold increase, followed by Nestin with a 4.5-fold increase and WNT11 with a 2.5-fold increase. CONCLUSIONS: This study has identified several major CNAs in oral cancer genomes and indicated that this correlates with over expression of the ISG15, WNT11, and Nestin genes.

A rare case of Dysphagia secondary to a large oesophageal lipoma.

Dysphagia is considered a warning symptom that requires exclusion of significant pathology such as oesophageal cancer, especially in elderly patients. Benign neoplasms of the oesophagus are rare. We report the case of a 69-year-old lady who presented with a five years history of infrequent intermittent dysphagia that had rapidly progressed over one month. This was associated with globus sensation, weight loss, intermittent episodes of stridor and aspiration pneumonia. Investigations revealed a large oesophageal lipoma in the proximal oesophagus extending down to the lower oesophagus. This was successfully resected via a left cervical approach. She remained well two years after the surgery.