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Background: The growth and proliferation of prostate cancer (PCa) have been shown to be associated with M1 muscarinic receptor subtypes (CHRM1) stimulation, via neural acetylcholine. Though both, M1 and M3 subtype has been established to... more
Background: The growth and proliferation of prostate cancer (PCa) have been shown to be associated with M1 muscarinic receptor subtypes (CHRM1) stimulation, via neural acetylcholine. Though both, M1 and M3 subtype has been established to be promoting growth, but the tissue distribution, implicit contribution and downstream pathways that are targeted by antagonism of these receptors remain to be established in the PCa of androgen sensitive and insensitive types. Objective: We intended to explore the differential expression pattern of CHRM1 over basal and luminal cells in PCa tissue and normal prostate. We attempt to relate the downstream signals originating from CHRM1 antagonism, to the morphological changes in PCa cell lines. In particular, we show the differences in cell death patterns and the role of antagonism at this receptor subtype, in prostate cancer growth and proliferation in-vitro on LNCaP and PC3 cell lines. Methods: PCa tissue and normal prostate tissue were examined by ...
We report four children from four inbred Arab families with varying manifestations of Hennekam syndrome and additional features that have not been previously reported. These include abnormalities of the middle ear, anomalous pulmonary... more
We report four children from four inbred Arab families with varying manifestations of Hennekam syndrome and additional features that have not been previously reported. These include abnormalities of the middle ear, anomalous pulmonary venous drainage, interrupted inferior vena cava, polysplenia, crossed renal ectopia, median position of the liver and multiple cavernous haemangiomas. In addition, in one case lymphoedema was absent and oedema due to hypoproteinaemia appeared at 6 years of age. Since anomalies of the veins and the consequent developmental abnormalities of the lymphatics might lead to alterations in the fluid balance of the embryo, we hypothesize that altered fluid dynamics due to defective vascular and lymphatic development might disrupt critical events in craniofacial morphogenesis resulting in Hennekam syndrome.
Research Interests: Intellectual Disability, Humans, Child, Female, Male, and 4 moreInfant, Clinical Sciences, Arabs, and Lymphedema
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Fifty clinical isolates comprising of Escherichia coli, Staphylococcus aureus, Klebsiella and Proteus were collected from different local pathological laboratories and their resistant pattern against two well known macrolides;... more
Fifty clinical isolates comprising of Escherichia coli, Staphylococcus aureus, Klebsiella and Proteus were collected from different local pathological laboratories and their resistant pattern against two well known macrolides; erythromycin and clarithromycin were studied using disc diffusion method. Klebsiella (41.67% against erythromycin and 58.34% against clarithromycin) and Proteus (66.67% against erythromycin and clarithromycin) species were found to be more resistant against the studied macrolides as compared to the rest of organisms. In case of Staphylococcus aureus and Escherichia.coli, resistant found were 27.78% and 23.54% against erythromycin and 22.23% and 35.30% against clarithromycin respectively. It is concluded from these figures that microbial resistance against these macrolides are increasing in our population which is alarming and therefore it is recommended to physicians to prescribe these antibiotics unless no other substitute is available in clinical practices.
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Research Interests: Microbiology, Immunology, Medical Microbiology, Biology, Treatment, and 21 moreAdolescent, Humans, Child, Blood brain barrier, Female, Animals, Male, Infant, Central Nervous System, Microbial Pathogenesis, Newborn Infant, Aged, Middle Aged, Adult, Emerging disease, Human Disease, Encephalitis, Early Diagnosis, Mortality rate, Lobosea, and Child preschool
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ABSTRACT Cores are the unit which read and execute program instruction. A single core processor has only one core and executes single instruction at a time. A multi-core processor has more than one independent processing core on a single... more
ABSTRACT Cores are the unit which read and execute program instruction. A single core processor has only one core and executes single instruction at a time. A multi-core processor has more than one independent processing core on a single chip to increase the performance. A multi-core processor can perform more than one operation at a time as per core. This means it can execute more than one instruction at a time which increases the performance and throughput of the processor. Theoretically, by adding extra core to the same chip increase the performance twice, however in practice speed of each core is slower than the single core processor. Similarly executing more instructions increases power usage and thus results in producing more heat. Again there is more cooling cost for these multi-core processors. Homogenous multi core processor has the same or identical cores but heterogeneous multi core processor have cores which are not identical. Softwares are written for multi core platform that can spread the workload across the multiple execution cores. This kind of functionality is known as "thread-level parallelism" or "threading". These specific techniques are called load balancing mechanism. In this paper we have summarized a number of load balancing algorithms that minimize the power consumption of multi-core technology and increase performance.
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Research Interests: Microbiology, Mass Spectrometry, Enzyme Inhibitors, Transmission Electron Microscopy, Cytoskeleton, and 15 moreBiological Sciences, Experimental parasitology, Humans, Parasite, Animals, Gas Chromatography, Mitogen Activated Protein Kinase, Amides, Pyridines, CARBOHYDRATES, Veterinary Sciences, Genistein, Protein Tyrosine Phosphatases, Linkage Analysis, and Acanthamoeba keratitis
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It is hypothesized that animals living in polluted environments possess antimicrobials to counter pathogenic microbes. The fact that snakes feed on germ-infested rodents suggests that they encounter pathogenic microbes and likely possess... more
It is hypothesized that animals living in polluted environments possess antimicrobials to counter pathogenic microbes. The fact that snakes feed on germ-infested rodents suggests that they encounter pathogenic microbes and likely possess antimicrobials. The venom is used only to paralyze the rodent, but the ability of snakes to counter potential infections in the gut due to disease-ridden rodents requires robust action of the immune system against a broad range of pathogens. To test this hypothesis, crude lysates of different organs of Naja naja karachiensis (black cobra) were tested for antimicrobial properties. The antimicrobial activities of extracts were tested against selected bacterial pathogens (neuropathogenic Escherichia coli K1, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Streptococcus pneumonia), protist (Acanthamoeba castellanii), and filamentous fungus (Fusarium solani). The findings revealed that plasma and various organ extracts of N. n. karachiensis exhibited antimicrobial activity against E. coli K1, MRSA, P. aeruginosa, S. pneumoniae, A. castellanii, and F. solani in a concentration-dependent manner. The results of this study are promising for the development of new antimicrobials.
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This paper presented the overview of the human resource practices in small and medium enterprises. The nature and importance of small and medium sized enterprises (SMEs) sector in... more
This paper presented the overview of the human resource practices in small and medium enterprises. The nature and importance of small and medium sized enterprises (SMEs) sector in Pakistan's economy is unparallel. Hence this paper discussed the general views of the SMEs operating in Pakistan, the current employment sector and the HR practices in SMEs. The arguments developed in the
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... 2011). 6 References Abrar, M., Zhilong, T. & Xinming, D. (2008). Innovation and Niche Marketing in Organic Textile: Opportunities for Pakistan, The 5th International Conference on Innovation and management, Maastricht... more
... 2011). 6 References Abrar, M., Zhilong, T. & Xinming, D. (2008). Innovation and Niche Marketing in Organic Textile: Opportunities for Pakistan, The 5th International Conference on Innovation and management, Maastricht University, The Netherlands. 1, pp. 292-296. ...
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This compilation will serve as an essential reference for microbiologists, immunologists, and physicians in the field of basic and medical microbiology, as well as an invaluable reference for new and experienced researchers who wish to understand this organism better. This book is the definitive ...more
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Human 17β-hydroxysteroid dehydrogenases (17βHSDs) catalyze the interconversion of weak and potent androgen and estrogen pairs. Although the reactions using purified enzymes can be driven in either direction, these enzymes appear to... more
Human 17β-hydroxysteroid dehydrogenases (17βHSDs) catalyze the interconversion of weak and potent androgen and estrogen pairs. Although the reactions using purified enzymes can be driven in either direction, these enzymes appear to function unidirectionally in intact cells: only reductive reactions for 17βHSD1 and 17β HSD3 and only oxidative reactions for 17βHSD2. We show that, after exhaustive incubations with either 17β-hydroxy- or 17-ketosteroid, the medium for HEK-293 cells expressing 17βHSD1 or 17βHSD3 contains a 92:8 ratio of reduced:oxidized steroid. Similarly, 17βHSD2 yields a >95:5 ratio of oxidized:reduced steroids for both androgens and estrogens. Dual-isotope kinetic measurements show that the rates of the forward and reverse reactions are identical at these functional equilibrium states in intact cells for all three 17βHSD isoforms, and these rates are much faster than those estimated from single-isotope flux studies. Mutation L36D converts 17βHSD1 to an oxidative enzyme in intact cells, reversing the equilibrium distribution of estradiol:estrone to 5:95; however, the rates of the forward and reverse reactions at equilibrium are equal and comparable to those of the wild-type enzymes. The co-expression of 17βHSD2 paradoxically increases the potency of estrone in transactivation assays, demonstrating the physiological relevance of “backwards” metabolism to estradiol. We conclude that 17βHSD types 1, 2, and 3 catalyze both oxidative and reductive reactions in HEK-293 cells at intrinsic rates that are much faster than those estimated from single-isotope studies. These 17βHSD isoforms do not drive steroid flux in one direction but rather may achieve functional equilibria in intact cells, reflecting thermodynamically driven steroid distributions.
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Research Interests: Microcirculation, Cell Adhesion, Cytotoxicity, Adhesion, Cell line, and 15 moreIn Vitro, Humans, Models, Endothelial Cells, Permeability, Blood brain barrier, Animals, Infection, Central Nervous System, Clinical Sciences, Genotype, Virulence Factors, Encephalitis, Extracellular, and Metalloproteases
The WNT pathway is a powerful signaling pathway that plays a crucial role in cell fate determination, survival, proliferation and movement in variety of tissues. Abnormalities in the WNT signaling pathway have been implicated in a number... more
The WNT pathway is a powerful signaling pathway that plays a crucial role in cell fate determination, survival, proliferation and movement in variety of tissues. Abnormalities in the WNT signaling pathway have been implicated in a number of diseases, most notably cancer. Recent exciting evidence suggests that WNT signaling also plays an important role in hematopoietic stem cell self-renewal and progenitor development. In this review we discuss current state of knowledge on WNT signaling in hematopoiesis and extend our focus on aberrant WNT signaling in hematological malignancies.
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Research Interests: Soil, Colorimetry, Cytotoxicity, Cell Culture, Clinical Microbiology, and 16 moreBiological Sciences, Contact Lenses, Water Supply, Humans, Contact Lens, United States, Animals, Clinical, Fresh water, Gel electrophoresis, Acanthamoeba, Pathogenicity, Zymography, Extracellular, Clinical Diagnosis, and Acanthamoeba keratitis
ABSTRACT A hypothesis is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, it needs to tested using scientific method(s). Scientists generally base scientific hypotheses on previous observations that... more
ABSTRACT A hypothesis is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, it needs to tested using scientific method(s). Scientists generally base scientific hypotheses on previous observations that cannot be explained otherwise. A scientific hypothesis is a proposed explanation of a phenomenon, until it is rigorously tested. In contrast, a scientific theory has undergone extensive testing and accepted to be the accurate explanation behind an observation. Here, the use of term ‘hyperthesis’ is introduced that highlights missing link between a scientific hypothesis and a scientific theory. It is believed that this term will be valuable in describing research that does not fit the scientific norm.
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Page 1. 1 Eyetext Monograph http://www.eyetext.net The pathogenesis of Acanthamoeba infections: current status and future implications Naveed Ahmed Khan School of Biological and Chemical Sciences, Birkbeck College ...
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Abstract The role of human resource practices (HRP) at its significance in small and medium enterprises (SME) become an emerging topic, especially in developing countries. This study aims to gauge the level of HR practice being exercise... more
Abstract The role of human resource practices (HRP) at its significance in small and medium enterprises (SME) become an emerging topic, especially in developing countries. This study aims to gauge the level of HR practice being exercise in SME. Quantitative approach has ...
Here, we determined the staining properties of Balamuthia mandrillaris cysts, and assessed the effect of 2, 6-dichlorobenzonitrile (DCB), a cellulose synthesis inhibitor, and calcofluor white, a brightening agent, on its encystment.... more
Here, we determined the staining properties of Balamuthia mandrillaris cysts, and assessed the effect of 2, 6-dichlorobenzonitrile (DCB), a cellulose synthesis inhibitor, and calcofluor white, a brightening agent, on its encystment. Periodic acid-Schiff reagent stained the inner wall intensely and middle and outer walls weakly suggesting that the cyst wall of B. mandrillaris may contain glycans. Furthermore, cysts, but not trophozoites, fluoresced when stained with calcofluor white. Calcofluor white and DCB, a cellulose synthesis inhibitor, inhibited B. mandrillaris encystment. This is the first report suggesting possible glycan biosynthesis in B. mandrillaris encystment, and this pathwaymay provide a potentially useful drug target and help improve treatment.
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Research Interests: Microbiology, Enzyme Inhibitors, Cytoskeleton, Signal Transduction, Experimental parasitology, and 15 moreBrain, Humans, Endothelial Cells, Parasite, Amides, Pyridines, Veterinary Sciences, Genistein, Chromones, Calcium Binding Proteins, Protein Binding, Galactose Binding, Protein Tyrosine Phosphatases, Protein Kinase Inhibitors, and Amoebozoa
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While there is a growing body of literature on nanostructured materials made by reverse microemulsion methods, there is little information on how the surfactants used to create these emulsions affect the final chemical properties of these... more
While there is a growing body of literature on nanostructured materials made by reverse microemulsion methods, there is little information on how the surfactants used to create these emulsions affect the final chemical properties of these nanoparticles. For catalytic applications, this residue can block active sites, which can have detrimental effects on reactivity. We have used thermogravimetric analysis, XPS, XRD,
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Automatic mass detection in mammograms is a challenging problem. The importance of this problem has attracted several researchers during the last decade and many algorithms have been proposed to deal with this problem. However, almost all... more
Automatic mass detection in mammograms is a challenging problem. The importance of this problem has attracted several researchers during the last decade and many algorithms have been proposed to deal with this problem. However, almost all these algorithms result in a large number of false positives/false negatives. For this problem, we introduce a new technique. The key idea of our approach is to represent textural properties of mammograms using Weber Local Descriptor (WLD), which has been shown outperforming stat-of-the-art best texture descriptors. The basic WLD descriptor is holistic by construction because it integrates the local information content into a single histogram. We extend it into a spatial WLD descriptor, which better encodes both the local region appearance and the spatial structure of the masses. Support Vector Machines (SVM) are employed for detecting masses and normal but suspicious parenchymal regions. The detection accuracy of the proposed system is Az = 0.988±...
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Light microscopy and electron microscopy have been successfully used in the study of microbes, as well as free-living protists. Unlike light microscopy, which enables us to observe living organisms or the electron microscope which... more
Light microscopy and electron microscopy have been successfully used in the study of microbes, as well as free-living protists. Unlike light microscopy, which enables us to observe living organisms or the electron microscope which provides a two-dimensional image, atomic force microscopy provides a three-dimensional surface profile. Here, we observed two free-living amoebae, Acanthamoeba castellanii and Balamuthia mandrillaris under the phase-contrast inverted microscope, transmission electron microscope and atomic force microscope. Although light microscopy was of lower magnification, it revealed functional biology of live amoebae such as motility and osmoregulation using contractile vacuoles of the trophozoite stage, but it is of limited value in defining the cyst stage. In contrast, transmission electron microscopy showed significantly greater magnification and resolution to reveal the ultra-structural features of trophozoites and cysts including intracellular organelles and cyst...
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Cancer cell dormancy is the main cause of cancer recurrence and failure of therapy as dormant cells evade not only the anticancer drugs but also the host immune system. These dormant cells veil themselves from detection by imaging and/or... more
Cancer cell dormancy is the main cause of cancer recurrence and failure of therapy as dormant cells evade not only the anticancer drugs but also the host immune system. These dormant cells veil themselves from detection by imaging and/or using biomarkers, which imposes an additional problem in targeting such cells. A similar form of hibernation process known as encystation is studied in detail for pathogenic unicellular eukaryotic microorganisms. By examination using microarray gene expression profiles, immunocytochemistry tools, and siRNAs during the process of encystation, understanding the covert features of cancer cell dormancy as proposed could be possible. This knowledge can be extended to dormant cancer cells to uncover the mechanisms that underlie this ghost, yet dangerous state of human cancers. We propose a strategy to induce dormancy and exit this state by application of knowledge gained from the encystation induction and retrieval processes in pathogenic eukaryotic micro...
Introduction Injection-locked long-wavelength Vertical-Cavity Surface Emitting Lasers (VCSELs) show promise as lowcost optical sources in communication systems [1]. However, the effect of polarised injection on the stability properties of... more
Introduction Injection-locked long-wavelength Vertical-Cavity Surface Emitting Lasers (VCSELs) show promise as lowcost optical sources in communication systems [1]. However, the effect of polarised injection on the stability properties of VCSELs has as yet not received much attention [2-4]. In this work, we report a novel theory combining the well-established spin-flip model (SFM), including noise, with the largest Lyapunov exponent (LLE) method to describe a 1550nm-VCSEL subject to polarised optical injection. Very good agreement is ...
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Acanthamoeba keratitis is a vision-threatening infection caused by pathogenic species of the genus Acanthamoeba. Although not all Acanthamoeba spp. can cause keratitis, it is important to differentiate pathogenic species and isolates from... more
Acanthamoeba keratitis is a vision-threatening infection caused by pathogenic species of the genus Acanthamoeba. Although not all Acanthamoeba spp. can cause keratitis, it is important to differentiate pathogenic species and isolates from nonpathogens. Since extracellular proteases may play a role in ocular pathology, we used colorimetric, cytopathic, and zymographic assays to assess extracellular protease activity in pathogenic and nonpathogenic Acanthamoeba. Colorimetric assays, using azo-linked protein as a substrate, showed extracellular protease activity in Acanthamoeba-conditioned medium and differentiated pathogenic and nonpathogenic Acanthamoeba. Monolayers of immortalized corneal epithelial cells in four-well plates were used for cytopathic effect (CPE) assays. Pathogenic Acanthamoeba isolates exhibited marked CPE on immortalized corneal epithelial cells, while nonpathogenic isolates did not exhibit CPE. Protease zymography was performed with Acanthamoeba-conditioned medium...
Research Interests: Soil, Colorimetry, Cytotoxicity, Cell Culture, Clinical Microbiology, and 16 moreBiological Sciences, Contact Lenses, Water Supply, Humans, Contact Lens, United States, Animals, Clinical, Fresh water, Gel electrophoresis, Acanthamoeba, Pathogenicity, Zymography, Extracellular, Clinical Diagnosis, and Acanthamoeba keratitis
Despite advances in antimicrobial chemotherapy and supportive care, the prognosis of Acanthamoeba infections remains poor, suggesting that new targets are needed that can affect parasite survival and host-pathogen interactions. G proteins... more
Despite advances in antimicrobial chemotherapy and supportive care, the prognosis of Acanthamoeba infections remains poor, suggesting that new targets are needed that can affect parasite survival and host-pathogen interactions. G proteins and their coupled receptors are well known regulators of a variety of cellular functions. The overall aim of the present study was to study the role of G-protein coupled receptor, β adrenergic receptor on the biology and pathogenesis of keratitis isolate of Acanthamoeba castellanii of the T4 genotype. Inhibition of β adrenergic receptor using antagonist, propranolol had detrimental effects on the extracellular proteolytic activities A. castellanii as determined using zymographic assays. Conversely, β adrenergic receptor agonist, isoprenaline showed increased proteases. Interestingly, β adrenergic receptor inhibition affected A. castellanii growth (using amoebistatic assays), viability (using amoebicidal assays by measuring uptake of Trypan blue) an...
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Balamuthia mandrillaris is a protist pathogen that can cause encephalitis with a fatality rate of >95%. This is due to our incomplete understanding of the pathogenesis and pathophysiology of B. mandrillaris encephalitis. B.... more
Balamuthia mandrillaris is a protist pathogen that can cause encephalitis with a fatality rate of >95%. This is due to our incomplete understanding of the pathogenesis and pathophysiology of B. mandrillaris encephalitis. B. mandrillaris has two stages in its life cycle, an active trophozoite stage during which it divides mitotically. However, under unfavorable conditions, the trophozoite transforms into a dormant cyst stage. A major concern during the course of therapy is that B. mandrillaris can transform into cysts. Cysts are highly resistant to physical and chemical conditions and present a problem in successful antimicrobial chemotherapy. Several lines of evidence suggest that B. mandrillaris encephalitis develops as a result of hematogenous spread, but it is unclear how circulating amoebae enter the central nervous system and cause inflammation, blood-brain barrier disruption, and neuronal injury. Recent studies have identified several parasite-host determinants for B. mandr...
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Acanthamoeba is a protist pathogen that can cause serious human infections including a blinding keratitis and a granulomatous amoebic encephalitis that almost always results in death. Current treatment includes a mixture of drugs and even... more
Acanthamoeba is a protist pathogen that can cause serious human infections including a blinding keratitis and a granulomatous amoebic encephalitis that almost always results in death. Current treatment includes a mixture of drugs and even then infection recurrence can occur. Photochemotherapy has shown promise in the treatment of Acanthamoeba infections, however selective targeting of pathogenic Acanthamoeba has remained a major concern. The mannose-binding protein is an important adhesin expressed on the surface membranes of pathogenic Acanthamoeba. To specifically target Acanthamoeba, the overall aim of this study was to synthesize photosensitising compound (porphyrin)-conjugated with mannose and test its efficacy in vitro. The synthesis of mannose-conjugated porphyrin was achieved by mixing benzaldehyde and pyrrole yielding tetra-phenyl porphyrin. Tetra-phenyl porphyrin was then converted into mono-nitro phenyl porphyrin by selectively nitrating the para position of phenyl rings ...
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ABSTRACT Cores are the unit which read and execute program instruction. A single core processor has only one core and executes single instruction at a time. A multi-core processor has more than one independent processing core on a single... more
ABSTRACT Cores are the unit which read and execute program instruction. A single core processor has only one core and executes single instruction at a time. A multi-core processor has more than one independent processing core on a single chip to increase the performance. A multi-core processor can perform more than one operation at a time as per core. This means it can execute more than one instruction at a time which increases the performance and throughput of the processor. Theoretically, by adding extra core to the same chip increase the performance twice, however in practice speed of each core is slower than the single core processor. Similarly executing more instructions increases power usage and thus results in producing more heat. Again there is more cooling cost for these multi-core processors. Homogenous multi core processor has the same or identical cores but heterogeneous multi core processor have cores which are not identical. Softwares are written for multi core platform that can spread the workload across the multiple execution cores. This kind of functionality is known as "thread-level parallelism" or "threading". These specific techniques are called load balancing mechanism. In this paper we have summarized a number of load balancing algorithms that minimize the power consumption of multi-core technology and increase performance.
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... MT Awan, S. Masud MIEEE, N. Khan MIEEE, F. Abdullah ... Blackfin BF533 has 8 data registers along with a provision to do the address arithmetic in address and index registers. Register scheduling has been incorporated in optimizing... more
... MT Awan, S. Masud MIEEE, N. Khan MIEEE, F. Abdullah ... Blackfin BF533 has 8 data registers along with a provision to do the address arithmetic in address and index registers. Register scheduling has been incorporated in optimizing the functions like 'D4i4_17_fast'. ...
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ABSTRACT We report a comprehensive study of the effects of polarized optical injection in long-wavelength Vertical-Cavity Surface Emitting Lasers (LW-VCSELs) emitting at the telecom wavelength of 1550nm. We analyze the properties of the... more
ABSTRACT We report a comprehensive study of the effects of polarized optical injection in long-wavelength Vertical-Cavity Surface Emitting Lasers (LW-VCSELs) emitting at the telecom wavelength of 1550nm. We analyze the properties of the polarization switching and bistability that can be induced in a 1550nm-VCSEL under orthogonal and arbitrary polarized optical injection. Additionally, we study the injection locking bandwidth of these devices when subject to different polarized optical injection. Furthermore, we also analyze the relationship existing between the injection locking bandwidth and the polarization switching range when the device is subject to orthogonally-polarized optical injection. Finally, we have identified regions of different nonlinear dynamics outside the injection locking bandwidth, including regions of periodic dynamics (such as limit cycle and period doubling) and chaos when these devices are subject to parallel and to orthogonal optical injection. This rich variety of nonlinear effects observed at 1550nm offers exciting prospects for novel practical uses of VCSELs in optical switching/routing applications in optical networks.
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Abstract We present our work analysing the effects of polarised optical injection in Long-Wavelength Vertical-Cavity Surface Emitting Lasers (LW-VCSELs). We review the properties of different phenomena such as polarisation switching (PS)... more
Abstract We present our work analysing the effects of polarised optical injection in Long-Wavelength Vertical-Cavity Surface Emitting Lasers (LW-VCSELs). We review the properties of different phenomena such as polarisation switching (PS) and bistability (PB) as well as on the different nonlinear dynamics (periodic and chaotic) arising in these devices under different cases of polarised optical injection.
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Granulomatous amoebic encephalitis due to Acanthamoeba is often a fatal human disease. However, the pathogenesis and pathophysiology of Acanthamoeba encephalitis remain unclear. In this study, the role of extracellular Acanthamoeba... more
Granulomatous amoebic encephalitis due to Acanthamoeba is often a fatal human disease. However, the pathogenesis and pathophysiology of Acanthamoeba encephalitis remain unclear. In this study, the role of extracellular Acanthamoeba proteases in central nervous system pathogenesis and pathophysiology was examined. Using an encephalitis isolate belonging to T1 genotype, we observed two major proteases with approximate molecular weights of 150 KD and 130 KD on SDS-PAGE gels using gelatin as substrate. The 130 KD protease was inhibited with phenylmethylsulfonyl fluoride (PMSF) suggesting that it is a serine protease, while the 150 KD protease was inhibited with 1, 10-phenanthroline suggesting that it is a metalloprotease. Both proteases exhibited maximal activity at neutral pH and over a range of temperatures, indicating their physiological relevance. These proteases degrade extracellular matrix (ECM), which provide structural and functional support to the brain tissue, as shown by the ...
Research Interests: Microcirculation, Extracellular Matrix, Biological Sciences, Protein Structure and Function, Brain, and 13 moreHumans, Blood brain barrier, Animals, Vascular endothelium, Central Nervous System, Ion Exchange Chromatography, Molecular weight, Human Disease, Acanthamoeba, Encephalitis, Serine Protease, Metalloproteases, and Acanthamoeba keratitis
Transmigration of neuropathogens across the blood-brain barrier is a key step in the development of central nervous system infections, making it a prime target for drug development. The ability of neuropathogens to traverse the... more
Transmigration of neuropathogens across the blood-brain barrier is a key step in the development of central nervous system infections, making it a prime target for drug development. The ability of neuropathogens to traverse the blood-brain barrier continues to inspire researchers to understand the specific strategies and molecular mechanisms that allow them to enter the brain. The availability of models of the blood-brain barrier that closely mimic the situation in vivo offers unprecedented opportunities for the development of novel therapeutics.