Rapid development and wide applications of nanotechnology brought about a significant increment on the number of engineered nanomaterials (ENs) inevitably entering our living system. Plants comprise of a very important living component of the terrestrial ecosystem. Studies on the influence of engineered nanomaterials (carbon and metal/metal oxides based) on plant growth indicated that in the excess content, engineered nanomaterials influences seed germination. It assessed the shoot-to-root ratio and the growth of the seedlings. From the toxicological studies to date, certain types of engineered nanomaterials can be toxic once they are not bound to a substrate or if they are freely circulating in living systems. It is assumed that the different types of engineered nanomaterials affect the different routes, behavior, and the capability of the plants. Furthermore, different, or even opposing conclusions, have been drawn from most studies on the interactions between engineered nanomaterials with plants. Therefore, this paper comprehensively reviews the studies on the different types of engineered nanomaterials and their interactions with different plant species, including the phytotoxicity, uptakes, and translocation of engineered nanomaterials by the plant at the whole plant and cellular level.
Different blur invariant descriptors have been proposed so far, which are either in the spatial domain or based on the properties available in the moment domain. In this paper, a frequency framework is proposed to develop blur invariant features that are used to deconvolve a degraded image caused by a Gaussian blur. These descriptors are obtained by establishing an equivalent relationship between the normalized Fourier transforms of the blurred and original images, both normalized by their respective fixed frequencies set to one. Advantage of using the proposed invariant descriptors is that it is possible to estimate both the point spread function (PSF) and the original image. The performance of frequency invariants will be demonstrated through experiments. An image deconvolution is done as an additional application to verify the proposed blur invariant features.
BACKGROUND AND AIMS: Acne is a common skin disorder which can cause physical scaring and impact the quality of life. The aim of this study is to determine the prevalence, severity and the risk factors for developing acne among medical students in Universiti Kebangsaan Malaysia (UKM).
MATERIALS AND METHODS: A cross sectional study among UKM medical students from academic year 1 to 5 was conducted from July 2011 to May 2012. A total of 361 students were selected by stratified cluster sampling method. Baseline data of the students, risk factors, height and weight were recorded. Acne severity was graded using the Comprehensive Acne Severity Scale (CASS).
RESULTS: The prevalence of acne among medical students is 68.1% (n=246). Males and females were almost equally affected (1:1.1). Majority students with acne were graded as almost clear (55.7%, n=137), mild (35.0%, n=86), moderate (7.7%, n=19), and severe (1.6%, n=4). More than half of them had developed acne scars (59.0%, n= 213). Males were found to be at higher risk of developing acne compared to females (p<0.05, OR=4.734; 95%CL=2.726-8.222). They are also at higher risk of developing moderate and severe grades of acne compared to females (p=0.001). The odds for developing acne was higher when mother (p=0.029; OR=1.752; 95%CL=1.058-2.902) or father (p=0.027; OR=1.852; 95%CL=1.072-3.201) had acne. When both parents were affected by acne the odds of developing acne was 3 times. (p=0.025; OR=3.056; 95%CL=1.153-8.094).
CONCLUSIONS: This study shows that the prevalence of acne among medical students is high. Hence, it is important to identify those at risk and provide optimal treatment to prevent scarring and possible low self esteem among these future doctors.
KEYWORDS: acne vulgaris; medical; prevalence; risk factors; severity; students
INTRODUCTION: Anaesthesia and surgery promote significant thermal disorder in the human body. Spinal anaesthesia causes lower limb vasodilation and redistribution of body heat from central to the peripheral compartments.
MATERIALS AND METHODS: This was a prospective, randomised, double-blind clinical study to compare the effectiveness of IV ketamine and tramadol in the prevention of shivering associated with spinal anaesthesia. We prospectively studied 150 ASA classification I and II patients between 18 and 70 years old scheduled for any elective surgery performed under spinal anaesthesia. Patients were randomly allocated to receive either prophylactic IV ketamine 0.5 mg/kg (Group K), IV tramadol 0.5 mg/kg (Group T) or normal saline as control (Group P) after intrathecal injection of 0.5% hyperbaric bupivacaine 12.5 mg (2.5 ml) and 25 mcg fentanyl. The frequency and degree of shivering, haemodynamic parameters, core body temperature and side effects of the studied drugs were recorded for the first 30 minutes.
RESULTS: The incidence of shivering was 8% in Group K, 16% in Group T and 24% in Group P. This result was statistically significant between Groups K and P. Patients from Group K also exhibited significantly higher mean arterial blood pressure and heart rate at 5 and 15 minutes post intrathecal injection while their mean core temperature was also significantly higher. Side effects such as nausea, vomiting, hallucination, agitation and sweating were comparable between all three groups. Patients from Group K however, had significant higher incidence of behavioural changes (blunted affect or catatonic state) and nystagmus.
CONCLUSIONS: Prophylactic use of IV ketamine 0.5 mg/kg significantly reduced the frequency and the intensity of perioperative shivering associated with spinal anaesthesia but also exhibited some side effects of the drug. Lower doses of prophylactic ketamine should be studied.
KEYWORDS: ketamine; shivering; spinal anaesthesia; tramadol
Infected aneurysm is a life threatening clinical condition that is associated with significant morbidity and mortality. Early detection is essential for a rapid and efficacious initial treatment for better prognosis. Since the introduction of antibiotic therapy and concomitant decline of endocarditis, true mycotic aneurysms are rarely seen. The usual treatment consists of antibiotics along with aggressive surgical debridement of the infected tissue and vascular reconstruction, if needed. We here describe an infected aneurysm presenting as pyrexia of unknown origin and discuss the clinical features and challenges encountered in the treatment.
Refeeding syndrome is a potentially fatal clinical condition characterized by severe electrolyte and fluid shifts associated with metabolic abnormalities in severely malnourished or starved patients undergoing oral, enteral or parenteral refeeding. We here present a case of a 50-year-old Indian male with a background of depression and alcoholic liver disease presented with alleged ingestion of a detergent. He subsequently developed an oesophageal stricture resulting in severe malnutrition. He developed refeeding syndrome following commencement of TPN associated with clear biochemical alteration. This was immediately identified and rectified. This case report highlights the prevalence of refeeding syndrome in a typical hospital setting that can easily be overlooked and stresses the importance of early recognition as this is a preventable disorder.
It has been a regular practice to repeatedly heat the cooking oil and consume it without knowing the harmful effects of such. The procedure to use repeatedly heated cooking oil is aimed to curb the cost of expenses. Heating results is the formation of free reactive oxygen species (ROS) which is responsible for the oxidative stress and damage to various organs in the body. The present review article discusses the harmful events occurring due to consumption of repeated heating of edible oil. A strong message is aimed to generate public awareness of the deleterious effects of consumption of heated edible oil which may help in curbing hypertension and atherosclerosis.
Liver disease is considered as one of the major complications in oxidative stress disorders like diabetes mellitus (DM). DM presents with deterioration in carbohydrate metabolism which is characterized with chronic hyperglycemia. The organ which involves in glucose or carbohydrate metabolism and is most likely to be affected is the liver. Deterioration in liver architecture and metabolism in DM, are considered as common findings. In the present review both biochemical and histological changes occurring in diabetic liver are conferred in detail. To counteract the oxidative stress disorders and its untoward complications, antioxidant or herbs have emerged as alternative medicine. The present review focuses on several herbs with antioxidant properties towards diabetic liver disease such as Liquorice, Pelargonium gravenolens, Momordica charantia, Propolis from bee hives, Dihar, Curcuma Longa, Tinospora cordifolia, Kangen-karyu, Parsley, Chard, Green tea Catechins and Piper sarmentosum (P.s). The herbs or the compounds present in herbs have potential to improve the liver metabolism and maintain the integrity of liver tissue in DM. The review also opens the door for effective use of herbal products for complications involved in the diabetic liver disease.
MeSH terms: Diabetes Mellitus*; Humans; Liver; Herbal Medicine
The role of anesthetists during orthopedic fluoroscopic procedures exposes them to radiation. We conducted a prospective, descriptive study to estimate the radiation exposure to anesthetists during procedures over a six-month period in the orthopedic trauma operating theatres which had the most fluoroscopic usage.
Breast cancer is a common cause of cancer mortality among women. Several genetic factors have been implicated in its development. Current treatment guidelines for estrogen receptor-positive breast cancer recommend that anastrozole [or any of the other two aromatase inhibitors (letrozole and exemestane)] is used as an alternative to tamoxifen or following several years of tamoxifen treatment. Nevertheless, this approach is still associated with many challenges, ranging from the recurrence of breast cancer to considerable interindividual variability in the tolerability of anastrozole, which may cause adverse effects, such as musculoskeletal symptoms, and lead to the withdrawal of many patients from treatment. Variabilities in the genes encoding the drug target (aromatase) or its metabolizing enzymes (CYP3A and UGT1A) contribute toward the interindividual variability in anastrozole's pharmacokinetics and/or pharmacodynamics. This paper reviews the role of genetic polymorphisms of CYP19A1, CYP3A4, and UGT1A4 in the responses of female hormone receptor-positive postmenopausal breast cancer patients to anastrozole. Many reviews in the literature have suggested that the study of functional polymorphisms and investigation of relevant genetic markers may provide valuable information in predicting responses to anastrozole in terms of its therapeutic and adverse effects. Nevertheless, more studies are required before the knowledge of its pharmacogenomics can be applied to the individualization of treatment to ensure that patients receive the maximum benefits. Therefore, future analyses, including but not limited to genome-wide association studies, are encouraged to address some of the gray areas in the pharmacogenomics of anastrozole therapy in postmenopausal breast cancer cases; this will help in providing guidance for future pharmacogenomics protocols when anastrozole is utilized in patients' management.
MeSH terms: Aromatase/genetics*; Breast Neoplasms/drug therapy*; Breast Neoplasms/genetics; Female; Humans; Nitriles/adverse effects; Nitriles/pharmacokinetics*; Triazoles/adverse effects; Triazoles/pharmacokinetics*; Glucuronosyltransferase/genetics*; Postmenopause; Antineoplastic Agents, Hormonal/adverse effects; Antineoplastic Agents, Hormonal/pharmacokinetics*; Polymorphism, Single Nucleotide; Cytochrome P-450 CYP3A/genetics*; Precision Medicine
Six weed species (Leptochola chinensis, Echinochloa crus-galli, Echinochloa colona, Jussiaea linifolia, Oryza sativa (weedy rice) and Cyperus iria) were tested for their salt tolerant traits in terms of chlorophyll, proline and mineral nutrients accumulation against different salinity levels (0, 4, 8, 16, 24, 32, and 40 dS m(-1)). Chlorophyll a, b and total chlorophyll content, proline and mineral nutrients accumulation were determined. Salt stress showed prominent effect on all the parameters investigated and there were significant variations between the all weed species. Chlorophyll content, K+, Ca(2+) and Mg(2+) ions in both shoots and roots significantly decreased; while proline and Na+ accumulation significantly increased with increasing salinity up to 40 dS m(-1). In terms of overall performance, Cyperus iria and E. crus-galliwere relatively more tolerant; E. colona and J. linifolia were tolerant; L. chinensis and O. sativa L were salt sensitive, respectively.
The morphological expressions and histopathological analysis of the gonads of a tropical marine neogastropod species (Thais sp.) from East Malaysia revealed new evidence of mechanical sterility in the imposex affected females. The gradual development of imposex was classified into five stages (Stage 0 to Stage 4) with three types of sterility conditions; Type A caused prohibition of copulation and capsule formation; Type B prohibits the releasing process of eggs; and gonads in Type C are infertile. Further analysis is needed to confirm, if the gonad malformation in imposex affected snails is generated specifically by tributyltin (TBT) or by other possible factors. The levels of imposex incidence (stages and percentages) were greater in a marina and decreased with increasing distance from the marina. Organotin tissue burden across the sexes showed that dibutyltin (DBT) as well as TBT might be the elements inducing imposex in Thais sp. from Miri in East Malaysia.
MeSH terms: Animals; Female; Gonads/drug effects*; Malaysia; Male; Disorders of Sex Development/chemically induced*; Trialkyltin Compounds/toxicity*; Water Pollutants, Chemical/toxicity*; Gastropoda/drug effects*
This study investigates the effect of ACE2 activation on leptin-induced changes in systolic blood pressure (SBP), proteinuria, endothelial activation and ACE2 expression during pregnancy in Sprague-Dawley rats. Pregnant rats were given subcutaneous injection of either saline, or leptin, or leptin plus xanthenone (ACE2 activator), or xanthenone (XTN) alone. SBP, serum ACE, ACE2, endothelin-1, E-selectin and ICAM-1 levels were estimated; also their gene expressions were determined in the kidney and aorta respectively. Compared to control, SBP was higher in the leptin-only treated group (P<0.001) and lower in rats treated with xanthenone alone (P<0.01). Proteinuria, markers of endothelial activation were significantly higher than controls in leptin-only treated rats (P<0.05). ACE2 activity and expression were lower in leptin-only treated rats when compared to controls (P<0.05). It seems, leptin administration during pregnancy significantly increases SBP, proteinuria, endothelial activation, but decreases ACE2 level and expression. These effects are prevented by concurrent administration of xanthenone.
Hepatocellular Carcinoma is the most common type of liver cancer having a strong relation with cirrhosis. Undoubtedly, cirrhosis may be caused by the virus infection of hepatitis B (HBV) and hepatitis C (HBC) or through alchoholism. However, even when cirrhosis has not been developed, patients with hepatitis viral infections are still at the risk of liver cancer. Apparently, among the numerous medical imaging techniques, Computed Tomography (CT) is the best in defining liver tumor borders. Unfortunately, these imaging techniques, including the CT procedures, usually rely on an appended application to reconstruct the generated 2-D slices to 3-D model. This may involve high performance computation, may be time-consuming or costly. Moreover, even with the outstanding performances of CT in defining the liver tumor boundaries, contrast between tumor tissues and the surrounding liver parenchyma is too low in CT slices. With such a close proxity in the tumor and the surrounding liver tissues, accurate characterization of liver tumor is a challenge. Previously, algorithms were developed to reveal abnormalities in brain's MRI datasets and CT abdominal pelvic, however, introducing a framework that could accurately characterize liver tumor and its surrounding tissues in CT datasets would go a long way in contributing to medical diagnosis and therapy planning of Hepatocellular Carcinoma. This paper proposes an Hepatocellular Carcinoma framework by extending the functionalities of SurLens Visualization System with an automatic liver tumor localization technique using Compute Unified Device Architecture (CUDA). The study was evaluated with liver CT datasets from the Imaging Science and Information Systems (ISIS) Center, the Georgetown University Medical Center. Significantly, visualization of liver CT datasets and the localization of the entangled tumor was achieved without prior datasets segmentation. Interestingly, the framework achieved remarkably good processing speed at a reasonably cheaper cost with an immediate reconstruction of the datasets and mapping of the tumor tissues within the surrounding liver parenchyma.
Feet displacement is recognized to be an important element in standing and is also linked to postural instability in elderly people with diabetes. This study investigates standing balance in diabetic patients in four asymmetric feet displacements. Quiet standing balance was investigated using the Biodex Balance System in 18 diabetic patients and compared with 18 control elderly subjects. The four standing conditions, namely, comfortable feet position, preferred feet position with a stance width of 17 cm and 15° angle between the medial borders, feet side by side, and heel side by side with a 30° angle between medial edges of feet were evaluated (i.e. eyes opened, eyes closed). The overall stability was calculated by measuring anterior-posterior and medial-lateral indices in standing conditions. Differences among feet positions were compared using an analysis of variance and the independent t-test. The diabetic patients were unstable in the medial-lateral direction when standing with feet side by side versus heel side by side with a 30° angle between medial edges of feet (p = 0.012 and 0.011, respectively), while in controls the anterior-posterior stability scores between standing in preferred foot position with stance width of 17 cm and 15° angle between the medial borders versus feet side by side, and heel side by side with a 30° angle between medial edges of feet versus preferred foot position with stance width of 17 cm and 15° angle between the medial borders had significant difference (p
Hepatitis B virus (HBV) has killed countless lives in human history. The invention of HBV vaccines in the 20(th) century has reduced significantly the rate of the viral infection. However, currently there is no effective treatment for chronic HBV carriers. Newly emerging vaccine escape mutants and drug resistant strains have complicated the viral eradication program. The entire world is now facing a new threat of HBV and human immunodeficiency virus co-infection. Could phage display provide solutions to these life-threatening problems? This article reviews critically and comprehensively the innovative and potential applications of phage display in the development of vaccines, therapeutic agents, diagnostic reagents, as well as gene and drug delivery systems to combat HBV. The application of phage display in epitope mapping of HBV antigens is also discussed in detail. Although this review mainly focuses on HBV, the innovative applications of phage display could also be extended to other infectious diseases.
MeSH terms: Animals; Antiviral Agents/therapeutic use*; Genotype; Hepatitis B virus/drug effects*; Hepatitis B virus/genetics; Hepatitis B virus/immunology; Hepatitis B virus/pathogenicity; Humans; Mutation; Predictive Value of Tests; Drug Design*; Gene Expression Regulation, Viral; Hepatitis B Vaccines/therapeutic use*; Epitope Mapping; Hepatitis B, Chronic/diagnosis; Hepatitis B, Chronic/drug therapy*; Molecular Targeted Therapy; Cell Surface Display Techniques*
Security-mediated cryptography was first introduced by Boneh et al. in 2001. The main motivation behind security-mediated cryptography was the capability to allow instant revocation of a user's secret key by necessitating the cooperation of a security mediator in any given transaction. Subsequently in 2003, Boneh et al. showed how to convert a RSA-based security-mediated encryption scheme from a traditional public key setting to an identity-based one, where certificates would no longer be required. Following these two pioneering papers, other cryptographic primitives that utilize a security-mediated approach began to surface. However, the security-mediated identity-based identification scheme (SM-IBI) was not introduced until Chin et al. in 2013 with a scheme built on bilinear pairings. In this paper, we improve on the efficiency results for SM-IBI schemes by proposing two schemes that are pairing-free and are based on well-studied complexity assumptions: the RSA and discrete logarithm assumptions.
In vivo dosimetry is important during radiotherapy to ensure the accuracy of the dose delivered to the treatment volume. A dosimeter should be characterized based on its application before it is used for in vivo dosimetry. In this study, we characterize a new MOSFET-based detector, the MOSkin detector, on surface for in vivo skin dosimetry. The advantages of the MOSkin detector are its water equivalent depth of measurement of 0.07 mm, small physical size with submicron dosimetric volume, and the ability to provide real-time readout. A MOSkin detector was calibrated and the reproducibility, linearity, and response over a large dose range to different threshold voltages were determined. Surface dose on solid water phantom was measured using MOSkin detector and compared with Markus ionization chamber and GAFCHROMIC EBT2 film measurements. Dependence in the response of the MOSkin detector on the surface of solid water phantom was also tested for different (i) source to surface distances (SSDs); (ii) field sizes; (iii) surface dose; (iv) radiation incident angles; and (v) wedges. The MOSkin detector showed excellent reproducibility and linearity for dose range of 50 cGy to 300 cGy. The MOSkin detector showed reliable response to different SSDs, field sizes, surface, radiation incident angles, and wedges. The MOSkin detector is suitable for in vivo skin dosimetry.
MeSH terms: Equipment Design; Humans; Organ Specificity/physiology*; Radiometry/instrumentation*; Radiotherapy, High-Energy/instrumentation*; Semiconductors*; Sensitivity and Specificity; Skin Physiological Phenomena*; Reproducibility of Results; Equipment Failure Analysis
The suspension system and socket fitting of artificial limbs have major roles and vital effects on the comfort, mobility, and satisfaction of amputees. This paper introduces a new pneumatic suspension system that overcomes the drawbacks of current suspension systems in donning and doffing, change in volume during daily activities, and pressure distribution in the socket-stump interface. An air pneumatic suspension system (APSS) for total-contact sockets was designed and developed. Pistoning and pressure distribution in the socket-stump interface were tested for the new APSS. More than 95% of the area between each prosthetic socket and liner was measured using a Tekscan F-Scan pressure measurement which has developed matrix-based pressure sensing systems. The variance in pressure around the stump was 8.76 kPa. APSS exhibits less pressure concentration around the stump, improved pressure distribution, easy donning and doffing, adjustability to remain fitted to the socket during daily activities, and more adaptability to the changes in stump volume. The volume changes were adjusted by utility of air pressure sensor. The vertical displacement point and reliability of suspension were assessed using a photographic method. The optimum pressure in every level of loading weight was 55 kPa, and the maximum displacement was 6 mm when 90 N of weight was loaded.
Understanding of kinematics force applied at the elbow is important in many fields, including biomechanics, biomedical engineering and rehabilitation. This paper provides a comparison of a mathematical model of elbow joint using three different types of prosthetics for transhumeral user, and characterizes the forces required to overcome the passive mechanical of the prosthetics at the residual limb.