This study was conducted to evaluate two routinely microscopic diagnostic methods in comparison with single-round PCR assay as the reference technique to detect Entamoeba histolytica/dispar/moshkovskii. Examination was performed on 500 stool samples obtained from Orang Asli communities in different states of Malaysia using formalin-ether sedimentation, trichrome staining and single-round PCR techniques. Ninety-three stool samples were detected E. histolytica/dispar/moshkovskii positive by routine microscopy, while single-round PCR detected 106 positive samples. Additional positives detected by PCR assay were eventually confirmed to be negative by both microscopic techniques. Detection rate of E. histolytica/dispar/moshkovskii was highest in combination techniques (18.6%), followed by trichrome staining (13.4%) and formalin-ether sedimentation (11.2%) techniques. Single-round PCR detected 21.2% of the stool samples. The sensitivity and specificity of formalin-ether sedimentation and trichrome staining techniques compared to the reference technique were 31.1% (95% CI: 29.0-36.0) and 94.2% (95% CI: 89.8-98.9), and 53.8% (95% CI: 46.0-76.2) and 97.5% (95% CI: 92.8-99.1), respectively. However, the sensitivity [59.4% (95% CI: 48.9-78.5)] of the method increased when both techniques were performed together, but the specificity decreased to 92.4% (95% CI: 81.0-98.0). The agreement between the reference technique, trichrome staining and combination techniques were statistically significant by Kappa statistics (trichrome staining: K = 0.592, p < 0.05; combination techniques: K = 0.543, p < 0.05). Hence, the combination technique is recommended to be used as a screening method in the diagnosis of E. histolytica/dispar/moshkovskii infections either for clinical or epidemiological study.
MicroRNAs (miRNAs) regulate various cellular processes. While several genes associated with replicative senescence have been described in endothelial cells, miRNAs that regulate these genes remain largely unknown. The present study was designed to identify miRNAs associated with replicative senescence and their target genes in human umbilical vein endothelial cells (HUVECs). An integrated miRNA and gene profiling approach revealed that hsa-miR-299-3p is upregulated in senescent HUVECs compared with the young cells, and one of its target genes could be IGF1. IGF1 was upregulated in senescent compared with young HUVECs, and knockdown of hsa-miR-299-3p dose-dependently increased the mRNA expression of IGF1, more significantly observed in the presenescent cells (passage 19) compared with the senescent cells (passage 25). Knockdown of hsa-miR-299-3p also resulted in significant reduction in the percentage of cells positively stained for senescence-associated β-galactosidase and increases in cell viability measured by MTT assay but marginal increases in cell proliferation and cell migration capacity measured by real-time growth kinetics analysis. Moreover, knockdown of hsa-miR-299-3p also increased proliferation of cells treated with H2O2 to induce senescence. These findings suggest that hsa-miR-299-3p may delay or protect against replicative senescence by improving the metabolic activity of the senesced cells but does not stimulate growth of the remaining cells in senescent cultures. Hence, these findings provide an early insight into the role of hsa-miR-299-3p in the modulation of replicative senescence in HUVECs.
The green algal genus Cladophora forms conspicuous nearshore populations in marine and freshwaters worldwide, commonly dominating peri-phyton communities. As the result of human activities, including the nutrient pollution of nearshore waters, Cladophora-dominated periphyton can form nuisance blooms. On the other hand, Cladophora has ecological functions that are beneficial, but less well appreciated. For example, Cladophora has previously been characterized as an ecological engineer because its complex structure fosters functional and taxonomic diversity of benthic microfauna. Here, we review classic and recent literature concerning taxonomy, cell biology, morphology, reproductive biology, and ecology of the genus Cladophora, to examine how this alga functions to modify habitats and influence littoral biogeochemistry. We review the evidence that Cladophora supports large, diverse populations of microalgal and bacterial epiphytes that influence the cycling of carbon and other key elements, and that the high production of cellulose and hydrocarbons by Cladophora-dominated periphyton has the potential for diverse technological applications, including wastewater remediation coupled to renewable biofuel production. We postulate that well-known aspects of Cladophora morphology, hydrodynamically stable and perennial holdfasts, distinctively branched architecture, unusually large cell and sporangial size and robust cell wall construction, are major factors contributing to the multiple roles of this organism as an ecological engineer.
MeSH terms: Chlorophyta; Azepines; Carbon; Cell Wall; Cellulose; Fresh Water; Humans; Human Activities; Hydrocarbons; Ecosystem; Biofuels; Microalgae; Waste Water
Context: Alpinia galanga Willd (Zingiberaceae) (AG) is a rhizomatous herb widely cultivated in shady regions of Malaysia, India, Indochina and Indonesia. It is used in southern India as a domestic remedy for the treatment of rheumatoid arthritis, cough, asthma, obesity, diabetes, etc. It was reported to have anti-obesity, hypoglycemic, hypolipidemic and antioxidant properties.
Objective: A flavonol glycoside, galangin, was isolated from AG rhizomes. Based on its in vitro pancreatic lipase inhibitory effect, the study was further aimed to clarify whether galangin prevented obesity induced in female rats by feeding cafeteria diet (CD) for 6 weeks.
Materials and methods: The in vitro pancreatic lipase inhibitory effect of galangin was determined by measuring the release of oleic acid from triolein. For in vivo experiments, female albino rats were fed CD with or without 50 mg/kg galangin for 6 weeks. Body weight and food intake was measured at weekly intervals. On day 42, serum lipids levels were estimated and then the weight of liver and parametrial adipose tissue (PAT) was determined. The liver lipid peroxidation and triglyceride (TG) content was also estimated.
Results: The IC50 value of galangin for pancreatic lipase was 48.20 mg/mL. Galangin produced inhibition of increased body weight, energy intake and PAT weight induced by CD. In addition, galangin produced a significant decrease in serum lipids, liver weight, lipid peroxidation and accumulation of hepatic TGs.
Conclusion: Galangin present in AG rhizomes produces anti-obesity effects in CD-fed rats; this may be mediated through its pancreatic lipase inhibitory, hypolipidemic and antioxidant activities.
A new dibenzotetraaza[14]annulene bearing two 3,3-dimethylindolenine fragments at the meso positions (LH(2)), has been synthesized through a nontemplate method. X-ray crystallography shows that the whole molecule is planar. The basicity of the indolenine ring permits the macrocycle to be protonated external to the core and form LH(4)(2+)·2Cl(-). Yet another structural modification having strong C-H···π interactions was found in the chloroform solvate of LH(2). The latter two modifications are accompanied by a degree of nonplanar distortion. The antiaromatic core of the macrocycle can accommodate a number of metal ions, Mn(III), Fe(III), Co(II), Ni(II) and Cu(II), to form complexes of [Mn(L)Br], [Mn(L)Cl], [Fe(LH(2))Cl(2)](+)·Cl(-), [Co(L)], [Ni(L)], and [Cu(L)]. In addition, the reaction of LH(2) with the larger Pd(II) ion leads to the formation of [Pd(2)(LH(2))(2)(OAc)(4)] wherein the macrocycle acts as a semiflexible ditopic ligand to coordinate pairs of metal ions via its indolenine N atoms into dinuclear metallocycles. The compounds LH(2), [Co(L)], and [Ni(L)] are isostructural and feature close π-stacking as well as linear chain arrangements in the case of the metal complexes. Variable temperature magnetic susceptibility measurements showed thermally induced paramagnetism in [Ni(L)].
Leptospira species were studied in water and soils from selected urban sites in Malaysia. A total of 151 water (n=121) and soil (n=30) samples were collected from 12 recreational lakes and wet markets. All samples were filtered and inoculated into semi-solid Ellinghausen and McCullough modified by Johnson and Harris (EMJH) media supplemented with additional 5-fluorouracil. The cultures were then incubated at 30°C and observed under a dark field microscope with intervals of 10 days. A PCR assay targeting the rrs gene was used to confirm the genus Leptospira among the isolates. Subsequently, the pathogenic status of the isolates was determined using primer sets G1/G2 and Sapro1/Sapro2, which target the secY and rrs genes, respectively. The isolates were identified at serogroup level using the microscopic agglutination test (MAT) while their genetic diversity was assessed by pulsed field gel electrophoresis (PFGE). Based on dark field microscopy, 23.1% (28/121) water and 23.3% (7/30) soil cultures were positive for Leptospira spp. Of the 35 positive cultures, only 8 were pure and confirmed as Leptospira genus by PCR assay. Two out of 8 isolates were confirmed as pathogenic, 5 were saprophytic and one was intermediate. These 8 isolates were negative for the 25 reference hyperimmune rabbit sera tested in the MAT. PFGE showed that all 8 of these environmental Leptospira spp. were genetically diverse. In conclusion, the presence of pathogenic Leptospira spp. in the urban Malaysian environment may indicate and highlight the importance of water screening, especially in recreational lakes, in order to minimize any chance of Leptospira infection.
Recent development of trilayer graphene nanoribbon Schottky-barrier field-effect transistors (FETs) will be governed by transistor electrostatics and quantum effects that impose scaling limits like those of Si metal-oxide-semiconductor field-effect transistors. The current-voltage characteristic of a Schottky-barrier FET has been studied as a function of physical parameters such as effective mass, graphene nanoribbon length, gate insulator thickness, and electrical parameters such as Schottky barrier height and applied bias voltage. In this paper, the scaling behaviors of a Schottky-barrier FET using trilayer graphene nanoribbon are studied and analytically modeled. A novel analytical method is also presented for describing a switch in a Schottky-contact double-gate trilayer graphene nanoribbon FET. In the proposed model, different stacking arrangements of trilayer graphene nanoribbon are assumed as metal and semiconductor contacts to form a Schottky transistor. Based on this assumption, an analytical model and numerical solution of the junction current-voltage are presented in which the applied bias voltage and channel length dependence characteristics are highlighted. The model is then compared with other types of transistors. The developed model can assist in comprehending experiments involving graphene nanoribbon Schottky-barrier FETs. It is demonstrated that the proposed structure exhibits negligible short-channel effects, an improved on-current, realistic threshold voltage, and opposite subthreshold slope and meets the International Technology Roadmap for Semiconductors near-term guidelines. Finally, the results showed that there is a fast transient between on-off states. In other words, the suggested model can be used as a high-speed switch where the value of subthreshold slope is small and thus leads to less power consumption.
Optical sensing offers an attractive option for detection of surface biopotentials in human subjects where electromagnetically noisy environments exist or safety requirements dictate a high degree of galvanic isolation. Such circumstances may be found in modern magnetic resonance imaging systems for example. The low signal amplitude and high source impedance of typical biopotentials have made optical transduction an uncommon sensing approach. We propose a solution consisting of an electro-optic phase modulator as a transducer, coupled to a vertical-cavity surface-emitting laser and the self-mixing signal detected via a photodiode. This configuration is physically evaluated with respect to synthesized surface electrocardiographic (EKG) signals of varying amplitudes and using differing optical feedback regimes. Optically detected EKG signals using strong optical feedback show the feasibility of this approach and indicate directions for optimization of the electro-optic transducer for improved signal-to-noise ratios. This may provide a new means of biopotential detection suited for environments characterized by harsh electromagnetic interference.
MeSH terms: Electrocardiography/instrumentation*; Electronics/instrumentation*; Equipment Design; Feasibility Studies; Humans; Interferometry/instrumentation*; Sensitivity and Specificity; Reproducibility of Results; Body Surface Potential Mapping/instrumentation*; Equipment Failure Analysis; Optical Devices*
Mesenchymal stem cells (MSC) generated from human umbilical cord (UC-MSC) and placenta (PLC-MSC) were assessed and compared for their immunomodulatory function on T cells proliferation by analysis of the cell cycle. Mitogen stimulated or resting T cells were co-cultured in the presence or absence of MSC. T-cell proliferation was assessed by tritiated thymidine ((3) H-TdR) assay and the mechanism of inhibition was examined bycell cycle and apoptosis assay. Both UC-MSC and PLC-MSC profoundly inhibited the proliferation of T-cell, mainly via cell-to-cell contact. MSC-mediated anti-proliferation does not lead to apoptosis,but prevented T cells from entering S phase and they therefore accumulated in the G(0) /G(1) phases. The anti-proliferative activity of MSC was related to this cell cycle arrest of T-cell. UC-MSC produced a greater inhibition than PLC-MSC in all measured parameters.
NP(Δc375) is a truncated version of the nucleocapsid protein of Newcastle disease virus (NDV) which self-assembles into a long helical structure. A packed bed anion exchange chromatography (PB-AEC), SepFastTM Supor Q pre-packed column, was used to purify NP(Δc375) from clarified feedstock. This PB-AEC column adsorbed 76.2% of NP(Δc375) from the clarified feedstock. About 67.5% of the adsorbed NP(Δc375) was successfully eluted from the column by applying 50 mM Tris-HCl elution buffer supplemented with 0.5 M NaCl at pH 7. Thus, a recovery yield of 51.4% with a purity of 76.7% which corresponds to a purification factor of 6.5 was achieved in this PB-AEC operation. Electron microscopic analysis revealed that the helical structure of the NP(Δc375) purified by SepFast(TM) Supor Q pre-packed column was as long as 490 nm and 22-24 nm in diameter. The antigenicity of the purified NP(Δc375) was confirmed by enzyme-linked immunosorbent assay.
Hydatidosis is a public health problem in many parts of the world, and improvement in diagnosis of the disease is still being pursued. Protoscoleces of Echinococcus granulosus were isolated from hydatid cysts collected from naturally infected sheep slaughtered in abattoirs in Iran. Sonicated extract of protoscolex was subjected to two-dimensional gel electrophoresis and Western blot analysis. Primary antibodies were from serum samples from 130 hydatidosis patients, 38 individuals infected with other parasitic infections, and 30 healthy people, whereas peroxidase (HRP)-conjugated anti-human IgG and IgG4 were used as secondary antibodies. The recombinant form of the identified protein was produced and tested for its sensitivity and specificity for the detection of human hydatidosis. An antigenic band of ∼60 kDa was found to be sensitive (82%) and specific (100%) for the detection of hydatidosis when probed with anti-human IgG4-HRP, while the sensitivity and specificity were 33 and 100%, respectively, with anti-human IgG-HRP. By mass spectrometry, the band was identified as protoscolex tegument paramyosin. The sensitivity and specificity of full-length paramyosin-recombinant protein in IgG4 blots were found to be 86 and 98%, respectively. In conclusion, IgG4 detection of Echinococcus granulosus paramyosin was found to be useful for the diagnosis of human hydatidosis.
Identification of pregnant women susceptible to rubella is important as vaccination can be given postpartum to prevent future risks of congenital rubella syndrome. However, in Malaysia, rubella antibody screening is not offered routinely to pregnant women in public funded health clinics due to cost constraint. Instead, a history of rubella vaccination is asked to be provided to establish the women's risk for rubella infection. The usefulness of this history, however, is not established. Thus, this paper aimed to determine the usefulness of a history of rubella vaccination in determining rubella susceptibility in pregnant women.
MeSH terms: Adolescent; Adult; Ambulatory Care Facilities; Antibodies, Viral/blood*; Cross-Sectional Studies; Disease Susceptibility/diagnosis; Female; Humans; Immunization; Malaysia; Maternal-Child Health Centers; Medical History Taking*; Predictive Value of Tests; Pregnancy; Pregnancy Complications, Infectious/prevention & control*; Rubella/immunology*; Rubella/prevention & control*; Rubella Vaccine; Rubella virus/immunology*; Sensitivity and Specificity; Serologic Tests/economics; Vaccination*; Confidence Intervals; Odds Ratio; Young Adult
This study was carried out to characterize phenolic compounds, carotenoids, vitamins and the antioxidant activity of selected wild edible plants. Plant extracts were purified, and phenolic compounds comprising 11 phenolic acids (hydroxybenzoic acid and hydrocinnamic acid) and 33 flavonoids (including catechin, glycosides and aglycones) were analysed using High Performance Liquid Chromatography - Diode Array Detector (HPLC-DAD). Furthermore, the contents of ascorbic acid and tocopherol ((α and γ tocopherol) and carotenoids (lutein and β-carotene) were also determined. The major phenolics identified consisted of glycosides of flavones (apigenin and luteolin) and flavonols (kaempferol and quercetin). Among the phenolic acids identified after hydrolysis, coumaric acid was the predominant phenolic acid in all the extracts of wild plants. Ascorbic acid [53.8 mg/100 g fresh weight (FW)] and β-carotene (656.5 mg/100 g FW) showed the highest content in the leaf of Heckeria umbellatum. In conclusion, the leaves of H. umbellatum, Aniseia martinicensis and Gonostegia hirta have excellent potential in the future to emerge as functional ingredients.
Cryptosporidium is a protozoan parasite of humans and animals and has a worldwide distribution. The parasite has a unique epidemiology in Middle Eastern countries where the IId subtype family of Cryptosporidium parvum dominates. However, there has been no information on Cryptosporidium species in Yemen. Thus, this study was conducted in Yemen to examine the distribution of Cryptosporidium species and subtype families. Fecal samples were collected from 335 patients who attended hospitals in Sana'a city. Cryptosporidium species were determined by PCR and sequence analysis of the 18 s rRNA gene. Cryptosporidium parvum and C. hominis subtypes were identified based on sequence analysis of the 60 kDa glycoprotein (gp60) gene. Out of 335 samples, 33 (9.9%) were positive for Cryptosporidium. Of them, 97% were identified as C. parvum whilst 1 case (3%) was caused by C. hominis. All 7 C. parvum isolates subtyped belonged to the IIaA15G2R1 subtype. The common occurrence of the zoonotic IIa subtype family of C. parvum highlights the potential occurrence of zoonotic transmission of cryptosporidiosis in Yemen. However, this postulation needs confirmation with future molecular epidemiological studies of cryptosporidiosis in both humans and animals in Yemen.
We developed a multiplex enzyme-based electrochemical genosensor for sequence-specific detection of multiplex linear-after-the-exponential-PCR amplicons that targeted toxigenic Vibrio cholerae O1 and O139 using novel screen-printed gold electrode bisensors.
OBJECTIVES: To examine the relationship between individual and work-related psychosocial factors and low back pain (LBP) and associated time off work in an occupational cohort.
METHODS: A self-administered questionnaire was completed by nurses working across 3 major public hospitals. Participants provided sociodemographic data and information on the occurrence of LBP, time off work, and psychosocial factors.
RESULTS: One thousand one hundred eleven participants (response rate 38.6%) were included in the study. Fifty-six percent of participants reported LBP in the previous year. When individual psychosocial factors were examined in the same model, the relationship between somatization and LBP persisted (OR 1.64; 95% confidence interval [CI], 1.35, 2.01). Low job security was also significantly associated with LBP independent of the other work-related factors (OR 0.82; 95% CI, 0.69, 0.98). Of those participants with LBP, 30% reported absence from work due to LBP. When absence from work was examined, negative beliefs (OR 0.97; 95% CI, 0.94, 1.00) and pain catastrophizing (OR 1.33; 95% CI, 1.04, 1.71) were independently associated with time off work, along with low job satisfaction (OR 0.71; 95% CI, 0.51, 0.97) and high job support (OR 1.35; 95% CI, 1.04, 1.75).
CONCLUSIONS: Somatization and low job security were found to be independently associated with occupational LBP, whereas negative beliefs, pain catastrophizing, reduced job satisfaction, and high job support were independently related to time off work. Longitudinal studies are needed to determine whether these individual and work-related psychosocial factors predict, or alternatively, are outcomes of pain and time off work associated with LBP.
The γ-aminobutyric acid (GABA) A receptor is composed of a variety of subunits and combinations and shows a characteristic distribution in the CNS. To date, 20 subunits of the GABA A receptor have been cloned: α1-6, β1-4, γ1-3, δ, π, ε , Θ, and ρ1-3. Oocyte of Xenopus laevis is one of the most frequently used heterologous expression systems, which are used to design and analyze specific combinations of GABA A receptor subunits. In oocytes, a certain GABA A receptor function is studied only by comparing the amplitude of the response to GABA and other drugs by physiological and pharmacological methods. According to the studies on Xenopus laevis oocytes, the α1β2γ2S receptor combination is mostly used. The α1-containing receptors mediate sedative and anticonvulsant acts. The results of studies on oocytes show that PKA, NKCC1, P2X3 receptors, and GABA A receptor-associated protein, etc., are existing systems that show different reactivity to the GABA A receptors. The GABA A receptor subunits contain distinct binding sites for BZDs, neurosteroids, general anesthetics, etc., which are responsible for the numerous functions of the GABA A receptor. A variety of other drugs, such as topiramate, TG41, (+)- and (-)-borneol, apigenin, and 6-methylflavone could also have modulatory effects on the GABA A receptors. Some of the different models and hypotheses on GABA A receptor structure and function have been achieved by using the two-electrode voltage clamp method in oocytes.
MeSH terms: Animals; Benzodiazepines/metabolism; Benzodiazepines/chemistry; Oocytes/metabolism; Protein Binding; Receptors, GABA-A/genetics; Receptors, GABA-A/metabolism*; Xenopus laevis/growth & development; Xenopus laevis/metabolism*; Protein Subunits/genetics; Protein Subunits/metabolism
E-health encompasses a wide scope and has excellent potential to grow in the future. Growing numbers of experts believe that e-health will fuel the next breakthroughs in health system improvements throughout the world. There is frequent evidence that largely indicates failures or unsustainable e-health implementations in different countries for different reasons. Iran is also a developing country that is presently applying this promising technology for its traditional healthcare delivery.
MeSH terms: Cost-Benefit Analysis; Developing Countries; Diffusion of Innovation; Health Policy; Humans; Iran; Medical Informatics Applications*; Qualitative Research