Well-defined image can assist user to identify region of interest during segmentation. However, complex medical image is usually characterized by poor tissue contrast and low background luminance. The contrast improvement can lift image visual quality, but the fundamental contrast enhancement methods often overlook the sudden jump problem. In this work, the proposed bihistogram Bezier curve contrast enhancement introduces the concept of "adequate contrast enhancement" to overcome sudden jump problem in knee magnetic resonance image. Since every image produces its own intensity distribution, the adequate contrast enhancement checks on the image's maximum intensity distortion and uses intensity discrepancy reduction to generate Bezier transform curve. The proposed method improves tissue contrast and preserves pertinent knee features without compromising natural image appearance. Besides, statistical results from Fisher's Least Significant Difference test and the Duncan test have consistently indicated that the proposed method outperforms fundamental contrast enhancement methods to exalt image visual quality. As the study is limited to relatively small image database, future works will include a larger dataset with osteoarthritic images to assess the clinical effectiveness of the proposed method to facilitate the image inspection.
Nipah virus and Hendra virus are closely related and following natural or experimental exposure induce similar clinical disease. In humans, encephalitis is the most serious outcome of infection and, hitherto, research into the pathogenesis of henipavirus encephalitis has been limited by the lack of a suitable model. Recently we reported a wild-type mouse model of Hendra virus (HeV) encephalitis that should facilitate detailed investigations of its neuropathogenesis, including mechanisms of disease recrudescence. In this study we investigated the possibility of developing a similar model of Nipah virus encephalitis.
A family of PI3Ks is the lipid kinases, which enhance intracellular pools of phosphatidyl inositol 3,4,5-tri-phosphate (PIP3) through phosphorylating its precursor. Amplifications and deletions of genes, as well as somatic missense of the PIK3CA gene have been described in many human cancer varieties, including of the brain, colon, liver, lung and stomach. Immunohistochemistry and Real-time quantitative PCR tests were used to determine the PIK3CA gene amplification (gene copy number) and to detect protein expression, respectively. The results obtained were analysed and the ratio of PIK3CA to β-actin gene copy number was calculated. Positive gene amplification of PIK3CA was appointed as a copy number of ≥4. Also, PI3K p110α protein expression was scored from 0 to 3+ and the scores of 2+ and 3+ were considered as positive for PI3K p110α protein expression. We studied 50 breast carcinoma samples for PI3K p110α protein expression and PIK3CA gene copy numbers. In general, 36 out of 50 (72%) breast carcinoma samples showed a significant increase in PIK3CA gene amplification. 12 out of 50 (24%) showed positive staining, and 38 out of 50 (76%) showed negative staining for PI3K p110α expression. We have identified no significant relationship between PIK3CA amplification, race (p= 0.630) and histological type (p=0. 731) in breast carcinoma, but correlation of PIK3CA amplification and age showed a significant relationship (p=0. 003) between them. No significant relationship has been identified in correlation of PI3K p110α protein expression compared to age (p=0. 284), race (p=0. 546) and histological type (p=0. 285). Amplification of PIK3CA was frequent in breast carcinoma and occurs in stages of breast carcinoma. Our result shows that there is a relationship between gene amplification and age in breast carcinoma. We suggest that PIK3CA is significant in breast tumorigenesis serve as a prevalent mechanism contributes to the oncogenic activation pathway of PIK3CA in breast cancer.
Parkinson's disease (PD) is a chronic neurodegenerative movement disorder characterized by the progressive and massive loss of dopaminergic neurons by neuronal apoptosis in the substantia nigra pars compacta and depletion of dopamine in the striatum, which lead to pathological and clinical abnormalities. A numerous of cellular processes including oxidative stress, mitochondrial dysfunction, and accumulation of α-synuclein aggregates are considered to contribute to the pathogenesis of Parkinson's disease. A further understanding of the cellular and molecular mechanisms involved in the pathophysiology of PD is crucial for developing effective diagnostic, preventative, and therapeutic strategies to cure this devastating disorder. Preconditioning (PC) is assumed as a natural adaptive process whereby a subthreshold stimulus can promote protection against a subsequent lethal stimulus in the brain as well as in other tissues that affords robust brain tolerance facing neurodegenerative insults. Multiple lines of evidence have demonstrated that preconditioning as a possible neuroprotective technique may reduce the neural deficits associated with neurodegenerative diseases such as PD. Throughout the last few decades, a lot of efforts have been made to discover the molecular determinants involved in preconditioning-induced protective responses; although, the accurate mechanisms underlying this "tolerance" phenomenon are not fully understood in PD. In this review, we will summarize pathophysiology and current therapeutic approaches in PD and discuss about preconditioning in PD as a potential neuroprotective strategy. Also the role of gene reprogramming and mitochondrial biogenesis involved in the preconditioning-mediated neuroprotective events will be highlighted. Preconditioning may represent a promising therapeutic weapon to combat neurodegeneration.
Familial hypercholesterolemia (FH) is a dominantly inherited disorder present from birth that markedly elevates plasma low-density lipoprotein cholesterol and causes premature coronary heart disease. There are at least 20 million people with FH worldwide, but the majority remains undetected, and current treatment is often suboptimal. To address this major gap in coronary prevention we present, from an international perspective, consensus-based guidance on the care of FH. The guidance was generated from seminars and workshops held at an international symposium. The recommendations focus on the detection, diagnosis, assessment, and management of FH in adults and children and set guidelines for clinical purposes. They also refer to best practice for cascade screening and risk notifying and testing families for FH, including use of genetic testing. Guidance on treatment is based on risk stratification, management of noncholesterol risk factors, and the safe and effective use of low-density lipoprotein-lowering therapies. Recommendations are given on lipoprotein apheresis. The use of emerging therapies for FH is also foreshadowed. This international guidance acknowledges evidence gaps but aims to make the best use of contemporary practice and technology to achieve the best outcomes for the care of FH. It should accordingly be used to inform clinical judgment and be adjusted for country-specific and local healthcare needs and resources.
Matched MeSH terms: Hyperlipoproteinemia Type II/pathology*
Copy number variation (CNV) is a form of genetic variation in addition to single nucleotide polymorphisms. The significance of CNV in the manifestation of a number of diseases is only recently receiving considerable attention. We genotyped 163 dengue patients from Peninsular Malaysia for genes possibly linked to dengue infection using quantitative real-time PCR. Here, we report a serendipitous discovery of a novel rare CNV of the ABCF1 gene among the dengue patients. Among these patients, two had a gain of 1 copy (CN = 3) and one had lost 1 copy (CN = 1), indicating that a rare CNV of the ABCF1 gene was detected among dengue patients from Peninsular Malaysia. Although the gene is suspected to regulate inflammatory responses and pathogen-induced cytokine storm, its relevance to dengue requires further investigation.
Parkinson's disease (PD) is not only characterized by its prominent motor symptoms but also associated with disturbances in cognitive and emotional functioning. The objective of the present study was to investigate the influence of emotion processing on inter-hemispheric electroencephalography (EEG) coherence in PD. Multimodal emotional stimuli (happiness, sadness, fear, anger, surprise, and disgust) were presented to 20 PD patients and 30 age-, education level-, and gender-matched healthy controls (HC) while EEG was recorded. Inter-hemispheric coherence was computed from seven homologous EEG electrode pairs (AF3-AF4, F7-F8, F3-F4, FC5-FC6, T7-T8, P7-P8, and O1-O2) for delta, theta, alpha, beta, and gamma frequency bands. In addition, subjective ratings were obtained for a representative of emotional stimuli. Interhemispherically, PD patients showed significantly lower coherence in theta, alpha, beta, and gamma frequency bands than HC during emotion processing. No significant changes were found in the delta frequency band coherence. We also found that PD patients were more impaired in recognizing negative emotions (sadness, fear, anger, and disgust) than relatively positive emotions (happiness and surprise). Behaviorally, PD patients did not show impairment in emotion recognition as measured by subjective ratings. These findings suggest that PD patients may have an impairment of inter-hemispheric functional connectivity (i.e., a decline in cortical connectivity) during emotion processing. This study may increase the awareness of EEG emotional response studies in clinical practice to uncover potential neurophysiologic abnormalities.
Teratoma of the neck is a rare extra-gonadal teratoma. Although it can be seen in adult, most of the cases present in fetal life or early childhood. Grading and classification of teratoma is important for management and prognosis. Decision making between mature and immature teratoma is sometime challenging if it is not composed of extensive unusual neuroectodermal tissue component. We reported a rare case of huge congenital mature cystic teratoma composted of various neuroectodermal tissues in an 8-month-old boy; it was located at the lateral neck and mimicked congenital cystic hygroma. A literature review was done to grade and classify the tumour.
Motivated by the success and exhaustive research on carbon nanotubes (CNTs) based drug delivery, graphene, a two-dimensional; honey-comb crystal lattice has emerged as the rising star in recent years. Graphene is a flat monolayer of carbon atoms that holds many promising properties such as unparalleled thermal conductivity, remarkable electronic properties, and most intriguingly higher planar surface and superlative mechanical strength, which are attractive in biotechnological applications. Delivery of anti-cancer drugs using graphene and its derivatives has sparked major interest in this emerging field. The anti-cancer therapies often pose a limitation of insolubility, administration problems and cell penetration ability. In addition, systemic toxicity caused by lack of selective targeting towards cancer cells and inefficient distribution limits its clinical applications. Graphene nanocomposite is a promising tool to address these drawbacks. This review will focus on various synthesis and functionalization of graphene and graphene oxide for providing better solubility and targeted drug delivery at cancer cells. A more advanced and 'smart' graphene hybrid nanostructures that have several functionalities such as stimulus-response mediated delivery, imaging at release sites as well as transfection into cancer cells are also presented. A brief description on the challenges and perspectives for future research in this field is also discussed.
The identification of new biomarkers for early detection of highly recurrent head and neck cancer is urgently needed. MicroRNAs (miRNAs) are small and non-coding RNAs that regulate cancer-related gene expression, such as tumor protein 53 (TP53) gene expression. This study was carried out to analyze TP53 gene expression using real-time PCR and to determine changes in intracellular p53 level by flow cytometry after downregulation of miRNA-181a miRNA inhibitor in the FaDu cell line. TP53 gene expression showed a 3-fold increment and the p53 protein level was also increased in the miRNA-181a-treated cells. In conclusion, miRNA-181a binds to the TP53 gene and inhibits its expression, decreasing the synthesis of p53.
Matched MeSH terms: Head and Neck Neoplasms/pathology
A 55-year-old immunocompetent woman was presented with features of obstructive jaundice and a clinicoradiological picture suggestive of a hilar cholangiocarcinoma (Klatskin tumour). However, caseating granulomatous lesion associated with miliary nodules were revealed intraoperatively. The lesion responded to standard antituberculous therapy. This unusual presentation highlights the considerable diagnostic challenge in such case.
As many as 31% of patients with nasopharyngeal carcinoma present with intracranial extension. Despite this high percentage, extension to the cerebellopontine angle is rare. The mechanism of tumor spread to the cerebellopontine angle is not completely understood. The most likely mechanism is direct extension to the skull base with involvement of the petrous apex and further extension posteriorly via the medial tentorial edge. We report the case of a 46-year-old woman with nasopharyngeal carcinoma who had been treated initially with chemoradiation and subsequently with stereotactic radiosurgery for residual tumor. One year later, she presented with an intracranial recurrence of the nasopharyngeal carcinoma in the cerebellopontine angle; the recurrence mimicked a benign tumor on magnetic resonance imaging. The tumor was ultimately diagnosed as an undifferentiated carcinoma of nasopharyngeal origin. She was treated with palliative chemotherapy.
Functional assessment of a coronary artery stenosis severity is generally assessed by fractional flow reserve (FFR), which is calculated from pressure measurements across the stenosis. The purpose of this study is to investigate the effect of porous media of the stenosed arterial wall on this diagnostic parameter. To understand the role of porous media on the diagnostic parameter FFR, a 3D computational simulations of the blood flow in rigid and porous stenotic artery wall models are carried out under steady state and transient conditions for three different percentage area stenoses (AS) corresponding to 70% (moderate), 80% (intermediate), and 90% (severe). Blood was modeled as a non Newtonian fluid. The variations of pressure drop across the stenosis and diagnostic parameter were studied in both models. The FFR decreased in proportion to the increase in the severity of the stenosis. The relationship between the percentage AS and the FFR was non linear and inversely related in both the models. The cut-off value of 0.75 for FFR was observed at 81.89% AS for the rigid artery model whereas 83.61% AS for the porous artery wall model. This study demonstrates that the porous media consideration on the stenotic arterial wall plays a substantial role in defining the cut-off value of FFR. We conclude that the effect of porous media on FFR, could lead to misinterpretation of the functional severity of the stenosis in the region of 81.89 %-83.61% AS.
MR imaging is an established tool for the detection and diagnosis of various injuries and internal derangements of the knee, enabling excellent anatomical visualization and producing good soft tissue contrast and characterization. However, numerous normal variants and potential pitfalls may lead to diagnostic errors. Understanding the basic MR imaging principles, applying the correct technique, knowing the normal anatomy and variants, recognizing artifacts, and assuring good clinical and radiographic correlation helps avoid these potential pitfalls.
To fully analyze and compare BMI among Han, Tibetan, and Uygur university students, to discuss the differences in their physical properties and physical health, and thus to provide some theoretical suggestions for the improvement of students' physical health.
Differing patterns of neurophysiological abnormalities have been reported in patients with Fisher syndrome. Fisher syndrome is rare, and few series have incorporated prospective serial studies to define the natural history of nerve conduction studies in Guillain-Barré syndrome.
Matched MeSH terms: Sensory Receptor Cells/pathology*; Miller Fisher Syndrome/physiopathology*
The feasibility of using the Patients Concerns Inventory (PCI) to identify oral cancer patient concerns during consultation in oral and maxillofacial specialist clinics in Malaysia was assessed. A cross-sectional study was conducted using a consecutive clinical sampling technique of all new and follow-up oral cancer patients. Surgeons and counter staff were also recruited. Two-thirds of patients were elderly, 63.9% female, 55.6% Indian, 63.9% of lower-level education, and half had the lowest level household income. Patient status was mostly post-treatment (87.5%) and most were at cancer stage III/IV (63.9%); 59.7% had surgery. Patients took an average 5.9 min (95% CI 5.1-6.7 min) to complete the PCI. Physical domain appeared highest (94.4%); social/family relationship issues (4.2%) were lowest. Significant associations included patient age-personal function (P=0.02); patient education level-emotional status (P=0.05) and social/family relationship issues (P=0.04), and patient TNM staging-personal function (P=0.03). The patients' mean feasibility score for the PCI was 5.3 (95% CI 5.1-5.5) out of 6. Patients (93.1%) and surgeons (90%) found the PCI to be feasible. Only 57.1% of counter staff agreed on the use of the PCI during patient registration. Overall, the PCI was considered feasible, thus favouring its future use in routine oral cancer patient management.
The widespread use of MRI in the assessment of low back pain has led to increased detection of degenerative cysts of the spine, which was essentially a surgical diagnosis earlier. The awareness of degenerative cysts, the significance of their role in the etiology of radicular and back pain and their effective management is evolving. We describe a case of bilateral, gas-filled lumbar facet synovial/ ganglion cysts causing focal arachnoid inflammation and lateral lumbar canal stenosis.
The study was conducted based on two objectives as framework. The first objective is to determine the point of microwave signal reflection while penetrating into the simulation models and, the second objective is to analyze the reflection pattern when the signal penetrate into the layers with different relative permittivity, εr. Thus, several microwave models were developed to make a close proximity of the in vivo human brain. The study proposed two different layers on two different characteristics models. The radii on the second layer and the corresponding antenna positions are the factors for both models. The radii for model 1 is 60 mm with an antenna position of 10 mm away, in contrast, model 2 is 10 mm larger in size with a closely adapted antenna without any gap. The layers of the models were developed with different combination of materials such as Oil, Sandy Soil, Brain, Glycerin and Water. Results show the combination of Glycerin + Brain and Brain + Sandy Soil are the best proximity of the in vivo human brain grey and white matter. The results could benefit subsequent studies for further enhancement and development of the models.
Breast cancer mostly arises from the glandular (dense) region of the breast. Consequently, breast density has been found to be a strong indicator for breast cancer risk. Therefore, there is a need to develop a system which can segment or classify dense breast areas. In a dense breast, the sensitivity of mammography for the early detection of breast cancer is reduced. It is difficult to detect a mass in a breast that is dense. Therefore, a computerized method to separate the existence of a mass from the glandular tissues becomes an important task. Moreover, if the segmentation results provide more precise demarcation enabling the visualization of the breast anatomical regions, it could also assist in the detection of architectural distortion or asymmetry. This study attempts to segment the dense areas of the breast and the existence of a mass and to visualize other breast regions (skin-air interface, uncompressed fat, compressed fat, and glandular) in a system. The graph cuts (GC) segmentation technique is proposed. Multiselection of seed labels has been chosen to provide the hard constraint for segmentation of the different parts. The results are promising. A strong correlation (r = 0.93) was observed between the segmented dense breast areas detected and radiological ground truth.