A spinal cord injury is damage to the nerves and cells that receive and provide a signal from the brain to the rest of the body. Spinal injury causes changes in movement, sensation, and strength, affect the body functions near the injury site, and may lead to paralysis. S100β was found as a suitable biomarker for identifying spinal cord injury and its causing problem. Herein, S100β immunoassay was developed on interdigitated electrode sensor to diagnose spinal cord injury. For effective anti-S100β antibody immobilization, the antibody was premixed with 3-Aminopropyl)triethoxsilane and then attached to the hydroxylated interdigitated electrode surface. This method of antibody immobilization enhanced the antibody attachment two-times than the method without premix. Antibody-attached surfaces increased current responses as S100 concentrations increased, and the limit of detection was seen to be 1 pg/mL on the linearity until 3000 pg/mL at an R2 value of 0.9907 [y = 7x - 6.4667]. Further, biofouling experiments with glial fibrillary acidic protein and γ-aminobutyric acid failed to enhance the current response, indicating the specific detection of S100β. This immunoassay identifies S100β at its lower level and helps to diagnose spinal cord injury and its related problem.
The application of antibodies in enzyme-linked immunosorbent assay (ELISA) is the basis of this diagnostic technique which is designed to detect a potpourri of complex target molecules such as cell surface antigens, allergens, and food contaminants. However, development of the systematic evolution of Ligands by Exponential Enrichment (SELEX) method, which can generate a nucleic acid-based probe (aptamer) that possess numerous advantages compared to antibodies, offers the possibility of using aptamers as an alternative molecular recognition element in ELISA. Compared to antibodies, aptamers are smaller in size, can be easily modified, are cheaper to produce, and can be generated against a wide array of target molecules. The application of aptamers in ELISA gives rise to an ELISA-derived assay called enzyme-linked apta-sorbent assay (ELASA). As with the ELISA method, ELASA can be used in several different configurations, including direct, indirect, and sandwich assays. This review provides an overview of the strategies involved in aptamer-based ELASA.
Oncologic outcomes following laparoscopic abdomino-perineal resection (APR) for distal rectal cancer are infrequently reported. This study aims to compare the long term outcomes between laparoscopic and open APR in distal rectal cancers.
Reporting biomolecular interactions has become part and parcel of many applications of science towards an in-depth understanding of disease and gene regulation. Apart from that, in diagnostic applications where biomolecules (antibodies and aptamers) are vastly applied, meticulous monitoring of biomolecular interaction is vital for clear-cut diagnosis. Several currently available methods of analyzing the interaction of the ligands with the appropriate analytes are aided by labeling using fluorescence or luminescence techniques. However, labeling is cumbersome and can occupy important binding sites of interactive molecules to be labeled, which may interfere with the conformational changes of the molecules and increase non-specificity. Optical-based sensing can provide an alternative way as a label-free procedure for monitoring biomolecular interactions. Optical sensors affiliated with different operating principles, including surface plasmon changes, scattering and interferometry, can impart a huge impact for in-house and point-of-care applications. This optical-based biosensing permits real-time monitoring, obviating the use of hazardous labeling molecules such as radioactive tags. Herein, label-free ways of reporting biomolecular interactions by various optical biosensors were gleaned.
We present the results and conclusions of an observational prospective cohort design study using self-administered questionnaires to determine correlation between psychosocial factors and cancer outcome among 80 consecutive newly diagnosed treatment naïve cancer subjects who were being referred to the Oncology Clinic, Hospital Universiti Kebangsaan Malaysia. Subjects were recruited over a period of 43 weeks from October 2000 till July 2001. Follow-up assessments were carried out at 6-months and 12 to 26 months later. The prediction of survival time was performed by the Cox Regression Analysis method with adjustments for biological and psychosocial risk factors. It was noted that depression (p = 0.001), stage 4 cancer disease (p = 0.016), neurological (p = 0.032), gastrointestinal tract (p = 0.04), head and neck (p = 0.011), gynaecological (p = 0.005) and bone and soft tissue (p = 0.030) malignancies were independent and statistically significant prognostic factor of survival during the study period. It was further shown than depressed patients were found to have almost four fold greater risk of dying than non-depressed patients and patients with stage 4 cancer illness have a five fold greater risk of dying than patients with stage 1 disease. Furthermore, based on tumour types subjects with neurological, gynaecological, head and neck, bone and soft tissue and gastro intestinal tract malignancies were found to have approximately thirty-six, twenty-five, twenty-two, sixteen and seven fold greater risk of dying respectively when compared to subjects with genitourinary cancers. This study further affirms the need for health care providers to be aware of the psychological aspects of the cancer patient and provide appropriate therapy so as to ensure that this group of individuals would have enhanced survival rates.
Study site: Oncology clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM)
Nanoparticle-mediated bio-sensing promoted the development of novel sensors in the front of medical diagnosis. In the present study, we have generated and examined the potential of titanium dioxide (TiO2) crystalline nanoparticles with aluminium interdigitated electrode biosensor to specifically detect single-stranded E.coli O157:H7 DNA. The performance of this novel DNA biosensor was measured the electrical current response using a picoammeter. The sensor surface was chemically functionalized with (3-aminopropyl) triethoxysilane (APTES) to provide contact between the organic and inorganic surfaces of a single-stranded DNA probe and TiO2 nanoparticles while maintaining the sensing system's physical characteristics. The complement of the target DNA of E. coli O157:H7 to the carboxylate-probe DNA could be translated into electrical signals and confirmed by the increased conductivity in the current-to-voltage curves. The specificity experiments indicate that the biosensor can discriminate between the complementary sequences from the base-mismatched and the non-complementary sequences. After duplex formation, the complementary target sequence can be quantified over a wide range with a detection limit of 1.0 x 10(-13)M. With target DNA from the lysed E. coli O157:H7, we could attain similar sensitivity. Stability of DNA immobilized surface was calculated with the relative standard deviation (4.6%), displayed the retaining with 99% of its original response current until 6 months. This high-performance interdigitated DNA biosensor with high sensitivity, stability and non-fouling on a novel sensing platform is suitable for a wide range of biomolecular interactive analyses.
Thirty-one patients treated at the Faculty of Dentistry, University of Malaya, were assessed for their satisfaction following orthognathic surgery. The female to male ratio was 22:9 with an age range of 17 to 36. Almost all patients (97%) listed appearance as one of their rationales for surgery. More males (78%) than females (59%) wanted functional improvement, while more females (91%) than males (33%) hoped for improvement in self-confidence. All patients reported esthetic improvement while 68% each reported improvement in mastication and self-confidence. Slightly more than half (52%) chose esthetic improvement as the single most important factor resulting in satisfaction. Almost ninety percent of male patients claimed satisfaction with functional improvement, while 68% of those who found satisfaction in improved self-confidence were females. Eighty-seven percent rated their post-surgical changes as being well accepted by their family. The impact of these findings on the success of the surgery and the need to reinforce verbal communication with printed pamphlets are emphasized.
We present a case of cervical necrotising fasciitis in a 56 year old man, secondary to a rare mastoid infection. The patient had coexisting diabetes mellitus and hypertension. He was treated with early surgical debridement followed by neck and chest reconstruction and radical mastoidectomy. Aggressive antibiotic therapy and supportive care was given. He recovered well with minimal residual functional deficit.
The results of a prospective study of 94 patients with history of ear, nose or aerodigestive tract foreign bodies were analysed. Sixty six to 94% of patients presented within 24 hours to a primary care doctor, 80 to 94% was referred to the ENT Department within 24 hours and 89 to 93% of patients had their foreign bodies removed within 24 hours. Overall, 58% of aural foreign bodies, 67% nasal foreign bodies and 94% of aerodigestive tract foreign bodies were removed within 48 hours of insertion. As a result of the prompt removal of foreign bodies in the majority of patients, no significant complications occurred. Foreign bodies in the aerodigestive tract tend to present earlier and more promptly removed compared with ear and nose foreign bodies. There was a significantly higher proportion of foreign body in the right ear and nostril compared to the left.
Normal rats, on being repetitively stressed by being restrained in a tight container for two hours, had higher levels of plasma corticosterone compared to pre stress values. These rats also reacted to the stress by a behavioral response in which there was marked decrease in locomotor activity assessed by the open field test (pre stress: 71.3 +/- 2.6 squares crossed versus post stress: 14.3 +/- 2.5 squares crossed) by counting the number of squares entered by the rat over 5 minutes. By the 6th to 7th exposures to the repetitive stress, the rats adapted to the stress and had normal plasma corticosterone levels and locomotor activity scores comparable to the pre stress values. These responses to stress were completely blocked by the administration of 0.32 microg/100 g BW of naloxone i.p at 10 minutes prior to the stress. In rats fed with rat chow supplemented with 90 mg/kg rat chow or 150 mg/kg rat chow of vitamin E, there was significant reduction of the plasma corticosterone levels and improvement in the locomotor activity. Stress thus caused opioid mediated increase in plasma corticosterone and reduction in locomotor activity which could be blocked by naloxone. These stress responses probably also involved generation of oxygen free radicals which were scavenged by the vitamin E, thus reducing the effects of repetitive stress on locomotor activity and serum corticosterone levels.
This is the first review on orthognathic surgery in Malaysia. The records of a total of 84 patients seen between 1977 and 1999 in the Department of Oral and Maxillofacial Surgery of the Faculty of Dentistry, University of Malaya were analysed. Skeletal III deformity formed 85% of the sample with a female dominance of 2 to 1. The patients' age ranged from 17 to 36 years, with a mean of 25.3 years. The common surgical techniques used were combined bilateral sagittal split and Le Fort I osteotomy. The predominant ethnic group was Chinese (n = 58, 69%); followed by Malay (n = 14, 17%) and Indian (n = 12, 14%).
We describe a 2 year-old non-immunocompromised girl with disseminated histoplasmosis who presented with a 2-month history of fever and bloody diarrhoea. On presentation, she was severely wasted and anaemic. There were gross hepatosplenomegaly and multiple lymphadenopathy. A septic screen was negative. A subsequent stool culture isolated Salmonella enteriditis. Serial Widal-Weil Felix (WWF) titres showed serological response after 2 weeks of Ceftriaxone. However, she continued to have spiking fever, bloody diarrhoea and weight loss. She developed pancytopaenia and disseminated intravascular coagulation. A bone marrow aspirate and trephine, and lymph node biopsy showed the presence of Histoplasma capsulatum, confirmed by Gomori-Methenamine Silver staining. She responded to intravenous amphotericin B followed by fluconazole (intravenous then oral) for 6 months after discharge. Human Immunodeficiency Virus screening tests were negative. Complement and immunoglobulin levels were normal. T and B enumeration tests showed gross leucopaenia with very low T cell function with defective phagocytic function. A repeat T and B cell enumeration test and phagocytic function tests done 3 months later were normal.
North American strains of Aedes albopictus, an Asian mosquito recently introduced into the Western Hemisphere, exhibit photoperiodic sensitivity and cold-hardiness characteristics similar to strains originating from temperate zone Asia. Trade statistics for used tire imports, the most likely mode of introduction, also indicate a north Asian origin. Aedes albopictus, an important vector of dengue and a potential vector of many other arboviral diseases, may therefore have the capability of infesting much of temperate North America.
A prospective study of all infrarenal abdominal aortic aneurysm (AAA) repairs both as electives and emergencies in Penang between January 1997 to December 2000 is presented. The objectives of the study were to determine the age, gender, racial distribution of the patients, the incidence, and risk factors and to summarize treatments undertaken and discuss the outcome. Among the races, the Malays were the most common presenting with infrarenal AAA. The mean age of patients operated was 68.5 years. Males were more commonly affected compared to females (12:1). Most infrarenal AAA repairs were performed as emergency operations, 33 cases (61.1%) compared to electives, 21 cases (38.9%). Total survival was 70.3% (elective 85.7%; emergency 57.6%). Mortality rate was 31.5% and the primary reason is the lack of operating time available for urgent operation and for treatment of concurrent disease states. Mycotic aneurysm with its triad of abdominal pain, fever and abdominal mass resulted in a significantly higher mortality (46.6%). Ninety six percent of the infrarenal AAA had transverse diameter greater than 6 cm. Morphologically 90.7% were fusiform AAA rather than saccular aneurysm (9.3%). Pulmonary complications (35.2%) were more common than cardiac complications (11.1%) possibly related to the urgent nature of the operation, smoking or history of pulmonary tuberculosis. Bleeding (14.8%) was the most common cause of mortality in ruptured mycotic infrarenal AAA.
This review covers a developmental progression on early to modern taxonomy at cellular level following the advent of electron microscopy and the advancement in deoxyribonucleic acid (DNA) extraction for expatiation of biological classification at DNA level. Here, we discuss the fundamental values of conventional chemical methods of DNA extraction using liquid/liquid extraction (LLE) followed by development of solid-phase extraction (SPE) methods, as well as recent advances in microfluidics device-based system for DNA extraction on-chip. We also discuss the importance of DNA extraction as well as the advantages over conventional chemical methods, and how Lab-on-a-Chip (LOC) system plays a crucial role for the future achievements.
1. This study was carried out to determine the effect of short-term and long-term ingestion of glycyrrhizic acid on the response to 2 h of restraint stress by measuring locomotor activity and plasma corticosterone levels. 2. Male Sprague-Dawley rats were randomly assigned into four groups, each group having eight rats. Group 1 (control) was given ordinary tap water, while groups 2 (short term), 3 and 4 (both long term) were given tap water containing 1 mg/mL glycyrrhizic acid to drink for 10 days, 4 weeks and 9 weeks, respectively. All the rats were subjected to 2 h of restraint stress and the locomotor activity assessed using an activity test in an open field arena followed by blood sampling to determine the plasma corticosterone level. These procedures were repeated daily for 14 days. 3. The basal locomotor activity scores for rats given glycyrrhizic acid for 10 days or 4 weeks were similar to those of controls; however, that of the rats treated long term with glycyrrhizic acid was significantly lower (21.0 +/- 3.0 squares crossed; P < 0.0005). Following the first period of restraint stress there was a highly significant decrease in locomotor activity, which remained significantly lower until the seventh and subsequent periods, indicating an adaptation to the repeated stress had occurred. Although the decrease in locomotor activity was partially blocked and adaptation to repetitive stress was enhanced in the rats given glycyrrhizic acid for 10 days, this was not seen in rats treated with glycyrrhizic acid for 4 or 9 weeks. The corticosterone levels in control rats were significantly elevated for 4-5 days following the exposure to repetitive stress but decreased gradually from day 7 onwards. However, both short- and long-term glycyrrhizic acid-treated rats had higher plasma corticosterone levels than the controls (P < 0.05). 4. In conclusion, repetitive restraint stress caused decreased locomotor activity associated with increased plasma corticosterone levels, both of which, in normal rats, decreased with adaptation to stress. The stress response was partially blocked and adaptation enhanced in rats given glycyrrhizic acid for 10 days, but not in rats given glycyrrhizic acid for 4 and 9 weeks. Glycyrrhizic acid ingestion caused high plasma corticosterone.
1. The present study examined the effect of naloxone (NAL), glycyrrhizic acid (GCA), deoxycorticosterone (DOC) and dexamethasone (DEX) on daily repeated 2 h chronic restrained stress (RS) on the locomotor activity (LA) of rats tested in the open field arena to elucidate the possible roles of opioids, glucocorticoids and mineralocorticoids in response to stress. 2. Intact and adrenalectomized (ADX) rats were either injected with 0.1 mL of NAL (0.32 microgram/100 g BW), 2.4 mg/kg DOC or 120 micrograms/kg DEX or had 1.0 mg/mL GCA dissolved in their drinking water or normal saline (for the ADX group) dissolved in their drinking water. 3. In intact groups, treatment with NAL completely blocked the stress response and treatment with GCA, DOC and DEX partially prevented the stress response. Adaptation occurred on either days 4, 5, 6 or 7 for intact rats treated with DEX, DOC, GCA or control rats, respectively. All ADX control rats died following the first 2 h RS. Adrenalectomized rats treated with DEX or DOC adapted later compared with intact rats, while rats given either GCA or NAL were unable to block or adapt to chronic RS. 4. These findings demonstrate that the stress response is primarily mediated by endogenous opioids, in that it is blocked by NAL. Both mineralocorticoids and glucocorticoids, which can act centrally to inhibit endorphins, partially blocked the stress response. The effect of GCA in intact rats was similar to that of both DEX and DOC in intact rats. Adrenalectomized rats treated with GCA (despite their lack of endogenous corticosterone) showed a stress response that was significantly different from the other ADX groups, implying that GCA had effects independent of endogenous corticosterone.
The pragmatic outcome of a lung cancer diagnosis is closely interrelated in reducing the number of fatal death caused by the world's top cancerous disease. Regardless of the advancement made in understanding lung tumor, and its multimodal treatment, in general the percentage of survival remain low. Late diagnosis of a cancerous cell in patients is the major hurdle for the above circumstances. In the new era of a lung cancer diagnosis with low cost, portable and non-invasive clinical sampling, nanotechnology is at its inflection point where current researches focus on the implementation of biosensor conjugated nanomaterials for the generation of the ideal sensing. The present review encloses the superiority of nanomaterials from zero to three-dimensional nanostructures in its discrete and nanocomposites nanotopography on sensing lung cancer biomarkers. Recent researches conducted on definitive nanomaterials and nanocomposites at multiple dimension with distinctive physiochemical property were focused to subside the cases associated with lung cancer through the development of novel biosensors. The hurdles encountered in the recent research and future preference with prognostic clinical lung cancer diagnosis using multidimensional nanomaterials and its composites are presented.
Interaction between split RNA aptamer and the clinically important target, HIV-1 Tat was investigated on a biosensing surface transduced by functionally choreographed multiwall carbon nanotubes (MWCNTs). Acid oxidation was performed to functionalize MWCNTs with carboxyl functional groups. X-ray photoelectron spectroscopy analysis had profound ~2.91% increment in overall oxygen group and ~1% increment was noticed with a specific carboxyl content owing to CO and OCO bonding. The interaction between split RNA aptamer and HIV-1 Tat protein was quantified by electrical measurements with the current signal (Ids) over a gate voltage (Vgs). Initially, 34.4 mV gate voltage shift was observed by the immobilization of aptamer on MWCNT. With aptamer and HIV-1 Tat interaction, the current flow was decreased with the concomitant gate voltage shift of 23.5 mV. The attainment of sensitivity with split aptamer and HIV-1 Tat interaction on the fabricated device was 600 pM. To ensure the genuine interaction of aptamer with HIV-1 Tat, other HIV-1 proteins, Nef and p24 were interacted with aptamer and they displayed the negligible interferences with gate voltage shift of 3.5 mV and 5.7 mV, which shows 4 and 2.5 folds lesser than HIV-1 Tat interaction, respectively.