110 research outputs found

    Compact printed hexagonal ultra wideband monopole antenna with band-notch characteristics

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    This article presents a compact, printed hexagonal monopole, ultra wideband antenna along with band-notch characteristics. The proposed monopole antenna consists of a printed hexagonal radiating element and a defected ground structure. Printed round-slot geometry and defected ground structure play a vital role in achieving the ultra wide bandwidth. Band-notch characteristics for eliminating the interference arising from the existing WLAN (5.15 – 5.825 GHz) band has been incorporated in the antenna frequency response by the insertion of C-shaped stubs near the feeding segment. The antenna shows a decent gain of ≥ 3.0 dBi throughout the entire bandwidth except at the notched frequency band. Measured results agree well with the simulated values

    A COMACT MICROSTRIP PATCH ANTENNA FOR WIRELESS COMMUNICATION

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    Abstract—A single feed compact rectangular microstrip antenna is presented in this paper. A triangular slot is introduced at the upper edge of the patch to reduce the resonant frequency. A small piece of triangular patch is added within the area of the triangular slot to improve the gain bandwidth performance of the antenna. The antenna size has been reduced by 46.2 % when compared to a conventional square microstrip patch antenna with a maximum of 160MHz bandwidth and −27.36 dB return loss. The characteristics of the designed structure are investigated by using MoM based electromagnetic solver, IE3D. An extensive analysis of the return loss, radiation pattern, gain and efficiency of the proposed antenna is shown in this paper. The simple configuration and low profile nature of the proposed antenna leads to easy fabrication and make it suitable for th

    Novel elvitegravir nanoformulation for drug delivery across the blood-brain barrier to achieve HIV-1 suppression in the CNS macrophages

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    The use of antiretroviral therapy (ART) has remarkably decreased the morbidity associated with HIV-1 infection, however, the prevalence of HIV-1-associated neurocognitive disorders (HAND) is still increasing. The blood-brain barrier (BBB) is the major impediment for penetration of antiretroviral drugs, causing therapeutics to reach only suboptimal level to the brain. Conventional antiretroviral drug regimens are not sufficient to improve the treatment outcomes of HAND. In our recent report, we have developed a poloxamer-PLGA nanoformulation loaded with elvitegravir (EVG), a commonly used antiretroviral drug. The nanoformulated EVG is capable of elevating intracellular drug uptake and simultaneously enhance viral suppression in HIV-1-infected macrophages. In this work, we identified the clinical parameters including stability, biocompatibility, protein corona, cellular internalization pathway of EVG nanoformulation for its potential clinical translation. We further assessed the ability of this EVG nanoformulation to cross the in vitro BBB model and suppress the HIV-1 in macrophage cells. Compared with EVG native drug, our EVG nanoformulation demonstrated an improved BBB model penetration cross the in vitro BBB model and an enhanced HIV-1 suppression in HIV-1-infected human monocyte-derived macrophages after crossing the BBB model without altering the BBB model integrity. Overall, this is an innovative and optimized treatment strategy that has a potential for therapeutic interventions in reducing HAND

    Tracing the Path to Sustainability: A Study on Domestic Electricity Consumption, Historical overview of Renewable energy resources, transitioning to sustainable energy sources and its impact on Health

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    Modern economies are centered on electricity, which is also contributing to an increasing amount of energy services. As a result of increased household incomes, electrification of transport and rising demand for digital connected devices and air conditioning, there will be a rise in the need for energy. Residential electricity consumption in India has tripled over the past few decades with houses having access to uninterrupted power supply. This study is conducted in order to understand the determinants of electricity consumption such as income, family size, stock of electrical appliances, size of dwellings and their influence on consumer’s electricity consumption. It also seeks to examine if the consumers are willing to reduce their electricity consumption and are interested in shifting to renewable energy resources considering the costs involved in shifting to more sustainable energies. Due to the nature of power, which is invisible from the moment it was discovered, as well as consumer attitudes and behavior, saving electricity may appear to be a challenging undertaking. However, if the consumer acquires a basic understanding of what electricity is, how it is utilized, and, more significantly, how energy is wasted, the problem might become very simple. This will make consumers more aware of wasteful electricity use and perhaps encourage them to modify their daily consumption of electricity

    Impact of lockdown measures on health outcomes of adults with Type 2 diabetes mellitus in Bangladesh

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    COVID-19 lockdown measures appreciably affected patients’ lifestyles, negatively impacting on their health. This includes patients with Type 2 Diabetes Mellitus (T2DM). Care of these patients was also negatively impacted due to a priority to treat patients with COVID-19, certainly initially, within hospitals and clinics in Bangladesh, combined with a lack of access to clinics and physicians due to lockdown and other measures. This is a concern in Bangladesh with growing rates of T2DM and subsequent complications. Consequently, we sought to critically analyze the situation among patients with T2DM in Bangladesh during the initial stages of the pandemic to address this information gap and provide future direction. Overall, 731 patients were recruited by a simple random sampling method among patients attending hospitals in Bangladesh, with data collected over 3 timescales: before lockdown, during the pandemic, and after lockdown. Data extracted from patients’ notes included current prescribed medicines and key parameters, including blood sugar levels, blood pressure, and comorbidities. In addition, the extent of record keeping. The glycemic status of patients deteriorated during lockdown, and comorbidities as well as complications related to T2DM increased during this period. Overall, a significant proportion of key datasets were not recorded in patients’ notes by their physician before and during lockdown. This started to change after lockdown measures eased. In conclusion, lockdown measures critically affected the management of patients with T2DM in Bangladesh, building on previous concerns. Extending internet coverage for telemedicine, introduction of structured guidelines, and appreciably increasing data recording during consultations is of the utmost priority to improve the care of T2DM patients in Bangladesh

    An Elvitegravir Nanoformulation Crosses the Blood–Brain Barrier and Suppresses HIV-1 Replication in Microglia

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    Even with an efficient combination of antiretroviral therapy (ART), which significantly decreases viral load in human immunodeficiency virus type 1 (HIV-1)-positive individuals, the occurrence of HIV-1-associated neurocognitive disorders (HAND) still exists. Microglia have been shown to have a significant role in HIV-1 replication in the brain and in subsequent HAND pathogenesis. However, due to the limited ability of ART drugs to cross the blood–brain barrier (BBB) after systemic administration, in addition to efflux transporter expression on microglia, the efficacy of ART drugs for viral suppression in microglia is suboptimal. Previously, we developed novel poly (lactic-co-glycolic acid) (PLGA)-based elvitegravir nanoparticles (PLGA-EVG NPs), which showed improved BBB penetration in vitro and improved viral suppression in HIV-1-infected primary macrophages, after crossing an in vitro BBB model. Our objective in the current study was to evaluate the efficacy of our PLGA-EVG NPs in an important central nervous system (CNS) HIV-1 reservoir, i.e., microglia. In this study, we evaluated the cyto-compatibility of the PLGA-EVG NPs in microglia, using an XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) assay and cellular morphology observation. We also studied the endocytosis pathway and the subcellular localization of PLGA NPs in microglia, using various endocytosis inhibitors and subcellular localization markers. We determined the ability of PLGA-EVG NPs to suppress HIV-1 replication in microglia, after crossing an in vitro BBB model. We also studied the drug levels in mouse plasma and brain tissue, using immunodeficient NOD scid gamma (NSG) mice, and performed a pilot study, to evaluate the efficacy of PLGA-EVG NPs on viral suppression in the CNS, using an HIV-1 encephalitic (HIVE) mouse model. From our results, the PLGA-EVG NPs showed ~100% biocompatibility with microglia, as compared to control cells. The internalization of PLGA NPs in microglia occurred through caveolae-/clathrin-mediated endocytosis. PLGA NPs can also escape from endo-lysosomal compartments and deliver the therapeutics to cells efficiently. More importantly, the PLGA-EVG NPs were able to show ~25% more viral suppression in HIV-1-infected human-monocyte-derived microglia-like cells after crossing the in vitro BBB compared to the EVG native drug, without altering BBB integrity. PLGA-EVG NPs also showed a ~two-fold higher level in mouse brain and a trend of decreasing CNS HIV-1 viral load in HIV-1-infected mice. Overall, these results help us to create a safe and efficient drug delivery method to target HIV-1 reservoirs in the CNS, for potential clinical use

    Asymmetric rotations and dimerization driven by normal to modulated phase transition in 4-biphenylcarboxy coupled L-phenylalaninate

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    Amongst the derivatives of 4-biphenylcarboxylic acid and amino acid esters, the crystal structure of 4-biphenylcarboxy-(L)-phenylalaninate is unusual owing to its monoclinic symmetry within a pseudo-orthorhombic lattice. The distortion is described by disparate rotational property around the chiral centers (φchiral\varphi_{\mathrm{chiral}} ≃\simeq -129 degrees and 58 degrees) of the two molecules in the asymmetric unit. Each of these molecules comprise of planar biphenyl moieties (φbiphenyl\varphi_{\mathrm{biphenyl}} = 0 degrees). Using temperature dependent single crystal X-ray diffraction experiments we show that the compound undergoes a phase transition below TT ∼\sim 124 K that is characterized by a commensurate modulation wave vector, q\mathbf{q} = δ(101)\delta(101), δ\delta = 12\frac{1}{2}. The (3+1) dimensional modulated structure at TT = 100 K suggests that the phase transition drives the biphenyl moieties towards non coplanar conformations with significant variation of internal torsion (φbiphenylmax\varphi^{\mathrm{max}}_{\mathrm{biphenyl}} ≤\leq 2020 degrees). These intramolecular rotations lead to dimerization of the molecular stacks that are described predominantly by intermolecular tilts and small variations in intermolecular distances. Atypical of modulated structures and superstructures of biphenyl and other polyphenyls, the rotations of individual molecules are asymmetric (Δ\Deltaφbiphenyl\varphi_{\mathrm{biphenyl}} ≈\approx 5 degrees) while φbiphenyl\varphi_{\mathrm{biphenyl}} of one independent molecule is two to four times larger than the other. Crystal-chemical analysis and phase relations in superspace suggest multiple competing factors involving intramolecular steric factors, intermolecular H--C⋅⋅⋅{\cdot}{\cdot}{\cdot}C--H contacts and weak C--H⋅⋅⋅{\cdot}{\cdot}{\cdot}O hydrogen bonds that govern the distinctively unequal torsional property of the molecules

    The global impact of the COVID-19 pandemic on the education of healthcare professionals, especially in low- and middle-income countries

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    The COVID-19 disaster has appreciably increased morbidity and mortality, as well as the delivery of healthcare, across countries exacerbated by the contagious nature of the virus.[1-4] Numerous public health measures were instigated across countries at the start of the pandemic to try and limit its spread without effective medicines and vaccines.[5,6] Introduced measures included lockdown activities, social distancing instructions, quarantining measures, wearing of personal protective equipment (PPEs), handwashing and sanitizers as well as the closure of borders.[5-8] Instigated measures also included the closure of universities appreciably affecting the education of healthcare professionals (HCPs), including physicians and pharmacists, across countries.[9-11] The extent of lockdown and other activities instigated during the early stages of the virus varied appreciably across countries leading to differences in observed morbidity and mortality rates.[12-15] For instance, comprehensive measures introduced early among several Asian countries including Korea, Malaysia, Taiwan, and Vietnam as well as among several African countries including Ghana, Malawi and Namibia, limited the number of deaths certainly when compared with Western European countries including Italy, Spain and the U

    A pilot study regarding the consequence of the COVID-19 pandemic on healthcare education in India and the implications

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    Introduction: The early approaches to prevent the spread of COVID-19 included lockdown and social distancing measures leading to university closures. These measures forced unparalleled changes to the delivery of healthcare education. Concerns included the preparedness of faculty and students to e-learning as well as the routine availability and funding of equipment and internet bundles. This needed addressing with fully trained healthcare professionals required given rising inappropriate use of antibiotics in India, growing prevalence of non-communicable diseases as well as patients with joint co-morbidities. Consequently, a need to ascertain the current impact of the pandemic on healthcare student education across India. Materials and Methods: Pilot study among ten purposely selected healthcare educators in both private and public universities. The questionnaire built on published studies. Results: Identified challenges included a lack of familiarity with online education, no bedside teaching, lack of equipment and affordability of internet bundles, poor internet connectivity and postponed examinations. Ways forward included faculty training on e-learning, providing students with loans and other financial support to purchase equipment and internet bundles, establishing COVID-19 prevention protocols and protective equipment, recording lectures and tutorials to make up for lost time, and simulated methods to teach clinical aspects. Conclusion: Despite the challenges, there was a rapid move to online learning among surveyed universities. Alongside this, courses to address lack of familiarity with e-Learning approaches with hybrid teaching approaches here to stay. The next step will be to undertake a wider study and use the combined findings to provide future guidance

    Targeting specific checkpoints in the management of SARS-CoV-2 induced cytokine storm

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    COVID-19-infected patients require an intact immune system to suppress viral replication and prevent complications. However, the complications of SARS-CoV-2 infection that led to death were linked to the overproduction of proinflammatory cytokines known as cytokine storm syndrome. This article reported the various checkpoints targeted to manage the SARS-CoV-2-induced cytokine storm. The literature search was carried out using PubMed, Embase, MEDLINE, and China National Knowledge Infrastructure (CNKI) databases. Journal articles that discussed SARS-CoV-2 infection and cytokine storm were retrieved and appraised. Specific checkpoints identified in managing SARS-CoV-2 induced cytokine storm include a decrease in the level of Nod-Like Receptor 3 (NLRP3) inflammasome where drugs such as quercetin and anakinra were effective. Janus kinase-2 and signal transducer and activator of transcription-1 (JAK2/STAT1) signaling pathways were blocked by medicines such as tocilizumab, baricitinib, and quercetin. In addition, inhibition of interleukin (IL)-6 with dexamethasone, tocilizumab, and sarilumab effectively treats cytokine storm and significantly reduces mortality caused by COVID-19. Blockade of IL-1 with drugs such as canakinumab and anakinra, and inhibition of Bruton tyrosine kinase (BTK) with zanubrutinib and ibrutinib was also beneficial. These agents' overall mechanisms of action involve a decrease in circulating proinflammatory chemokines and cytokines and or blockade of their receptors. Consequently, the actions of these drugs significantly improve respiration and raise lymphocyte count and PaO2/FiO2 ratio. Targeting cytokine storms' pathogenesis genetic and molecular apparatus will substantially enhance lung function and reduce mortality due to the COVID-19 pandemic.https://www.mdpi.com/journal/lifeam2023Pharmacolog
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