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Place is everywhere as geography, location, territory, and landscape permeates everyday encounter. In contrast, memory is embedded in the physical setting as the burgeoning narratives of cities. In recent instances, literary settings of novels and characters are interpretations of actual life events. An immigrant from New York City returns to Lagos after a long period in Teju Cole's Every Day is for the Thief (2007) and (2014) investigates the correlation of the past self within the present state of the setting. Exploring interrelated memories and places to revisit the sense of self, the present study aims to analyse how autobiographical memory distinguishes personal memory from social events and defines place attachment and identity in society. This article also explores the lack of conformity to the tendency to find the past self in different time and spatial aspects through which this research tries to bridge the past with the present using narrators' autobiographical memories.
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Memória Episódica , Humanos , Adulto , Feminino , Masculino , Autoimagem , Adulto Jovem , Rememoração Mental , Pessoa de Meia-IdadeRESUMO
Genetic disorders are significant contributors to infant hospitalization and mortality globally. The early diagnosis of these conditions in infants remains a considerable challenge. Clinical exome sequencing (CES) has shown to be a successful tool for the early diagnosis of genetic conditions, however, its utility in African infant populations has not been investigated. The impact of the under-representation of African genomic data, the cost of testing, and genomic workforce shortages, need to be investigated and evidence-based implementation strategies accounting for locally available genetics expertise and diagnostic infrastructure need to be developed. We evaluated the diagnostic utility of singleton CES in a cohort of 32 ill, South African infants from two State hospitals in Johannesburg, South Africa. We analysed the data using a series of filtering approaches, including a curated virtual gene panel consisting of genes implicated in neonatal-and early childhood-onset conditions and genes with known founder and common variants in African populations. We reported a diagnostic yield of 22% and identified seven pathogenic variants in the NPHS1, COL2A1, OCRL, SHOC2, TPRV4, MTM1 and STAC3 genes. This study demonstrates the utility value of CES in the South African State healthcare setting, providing a diagnosis to patients who would otherwise not receive one and allowing for directed management. We anticipate an increase in the diagnostic yield of our workflow with further refinement of the study inclusion criteria. This study highlights important considerations for the implementation of genomic medicine in under-resourced settings and in under-represented African populations where variant interpretation remains a challenge.
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Correction for 'Blood brain barrier permeable gold nanocluster for targeted brain imaging and therapy: an in vitro and in vivo study' by L. V. Nair et al., J. Mater. Chem. B, 2017, 5, 8314-8321, https://doi.org/10.1039/C7TB02247F.
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All landscapes, including estuarine islands, normally try to restore their geomorphic isostasy in all anthropogenic interventions on land dynamics. Munroe Island has been experiencing drastic environmental degradation, such as land subsidence, severe tidal/monsoon flooding, subsidence of build-ups and a drastic decay in agricultural productivity. This paper examines the role of anthropo-geomorphic interventions causing for the land degradation in Munroe Island through a multidisciplinary approach. Multidated, multiresolution satellite products and published maps, spanning a period of about six decades from 1960 to 2021, were used to understand the different geomorphic and geographical processes in the study area. Evaluation of the temporal bathymetric datasets, salinity measurements of the river and estuary, borehole data logs of the area and electrical resistivity surveys of the island were analyzed to find out the causative factors for the disturbances in the land neutrality, along with the tidal hydrodynamic changes in the region. The study shows about 14% of the total land area was vanished during the study period, and more than 25% of the area is under stress, leading to further land degradation. More than 500 households are forced to vacate their residence due to land subsidence/flooding. Lack of required freshwater and sediment supply from the Kallada river after the construction of the Thenmala reservoir in the Kallada river as well as the uncontrolled sand mining prevailed are the key factors for the environmental degradation of Munroe Island. The paper describes the role and colinkages of human-induced hydrogeomorphic interventions on a geomorphic system, in charge of the environmental degradation and land subsidence crisis of an estuarine island ecosystem and discusses the concerns related to the management strategies of such region.
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Regenerative engineering has pioneered several novel biomaterials to treat critical-sized bone injuries. However, despite significant improvement in synthetic materials research, some limitations still exist. The constraints correlated with the current grafting methods signify a treatment paradigm shift to osteoinductive regenerative engineering approaches. Because of their intrinsic potential, inductive biomaterials may represent alternative approaches to treating critical bone injuries. Osteoinductive scaffolds stimulate stem cell differentiation into the osteoblastic lineage, enhancing bone regeneration. Inductive biomaterials comprise polymers, calcium phosphate ceramics, metals, and graphene family materials. This review will assess the cellular behavior toward properties of inductive materials.
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Regeneração Óssea , Engenharia Tecidual , Materiais Biocompatíveis , Diferenciação Celular , CerâmicaRESUMO
Blood brain barrier (BBB) is a dynamic interface, comprising polarized endothelial cells, that separates the brain from the circulatory system. The highly protective nature of this tight junction impairs diagnosis and treatment of brain disorders. In this study, we designed a sub atomic size, near infrared emitting, dual function glutathione gold cluster with high fluorescence yield to facilitate permeability of BBB, for imaging applications and drug delivery. The gold cluster was then modified with Levodopa (l-dopa), to utilize the large amino acid transporter 1 (LAT1) pathways to enhance brain entry. Uptake and permeability of the nanoprobes were demonstrated using an established model of BBB, comprising brain endothelial cells (bEnd.3). The uptake and the clearance of l-dopa modified cluster was faster than the glutathione cluster. l-Dopa modified cluster supports the slow and sustained delivery of a model drug, pilocarpine, to the brain. Results of in vivo imaging and drug release in normal mice hold promise for considering the probe for early diagnosis of brain diseases, when the barrier is not disrupted, and for subsequent drug treatment.
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Mitochondria are critical for respiration in all tissues; however, in liver, these organelles also accommodate high-capacity anaplerotic/cataplerotic pathways that are essential to gluconeogenesis and other biosynthetic activities. During nonalcoholic fatty liver disease (NAFLD), mitochondria also produce ROS that damage hepatocytes, trigger inflammation, and contribute to insulin resistance. Here, we provide several lines of evidence indicating that induction of biosynthesis through hepatic anaplerotic/cataplerotic pathways is energetically backed by elevated oxidative metabolism and hence contributes to oxidative stress and inflammation during NAFLD. First, in murine livers, elevation of fatty acid delivery not only induced oxidative metabolism, but also amplified anaplerosis/cataplerosis and caused a proportional rise in oxidative stress and inflammation. Second, loss of anaplerosis/cataplerosis via genetic knockdown of phosphoenolpyruvate carboxykinase 1 (Pck1) prevented fatty acid-induced rise in oxidative flux, oxidative stress, and inflammation. Flux appeared to be regulated by redox state, energy charge, and metabolite concentration, which may also amplify antioxidant pathways. Third, preventing elevated oxidative metabolism with metformin also normalized hepatic anaplerosis/cataplerosis and reduced markers of inflammation. Finally, independent histological grades in human NAFLD biopsies were proportional to oxidative flux. Thus, hepatic oxidative stress and inflammation are associated with elevated oxidative metabolism during an obesogenic diet, and this link may be provoked by increased work through anabolic pathways.
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Hepatócitos/metabolismo , Mitocôndrias Hepáticas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estresse Oxidativo , Animais , Hepatócitos/patologia , Humanos , Inflamação/metabolismo , Inflamação/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Mitocôndrias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Ratos , Ratos WistarRESUMO
Osteoarthritis (OA) is the most prevalent musculoskeletal disease in humans, causing pain, loss of joint motility and function, and severely reducing the standard of living of patients. Cartilage tissue engineering attempts to repair the damaged tissue of individuals suffering from OA by providing mechanical support to the joint as new tissue regenerates. The aim of this study was to create composite three dimensional scaffolds comprised of electrospun poly(D,L-lactide)/poly(L-lactide) (PDLA/PLLA) or poly(D,L-lactide)/polycaprolactone (PDLA/PCL) with salt leached pores and an embedded chitosan hydrogel to determine the potential of these scaffolds for cartilage tissue engineering. PDLA/PLLA-hydrogel scaffolds displayed the largest compressive moduli followed by PDLA/PCL-hydrogel scaffolds. Dynamic mechanical tests showed that the PDLA/PLLA scaffolds had no appreciable recovery while PDLA/PCL scaffolds did exhibit some recovery. Primary canine chondrocytes produced both collagen type II and proteoglycans (primary components of extracellular matrix in cartilage) while being cultured on scaffolds composed of electrospun PDLA/PCL. As a result, a composite electrospun embedded hydrogel scaffold shows promise for treating individuals suffering from OA.
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Cartilagem/química , Quitosana/química , Hidrogéis , Nanofibras , Polímeros/química , Engenharia Tecidual , Alicerces Teciduais , Teste de MateriaisRESUMO
Lactoferrin, a member of the "Siderophilin" family, is an iron binding glycoprotein. Lactoferrin is produced by various exocrine glands in our body and is abundantly present in milk and colostrums. The uniqueness of lactoferrin as a skeletal regenerative molecule lies in its ability to favorably modulate the responses of the various cell types involved in musculoskeletal regeneration. Lactoferrin exhibits pleiotropic functions and recent studies indicate that lactoferrin promotes the proliferation and differentiation of osteoblast cells and inhibits osteoclast-mediated bone resorption. Human lactoferrin is also known to promote neovascularization. This review aims to summarize the most recent studies on lactoferrin focusing on its anabolic effect to bone tissue and the ability to modulate immune responses with specific focus on osteoimmunology.
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Regeneração Óssea/efeitos dos fármacos , Lactoferrina/farmacologia , Animais , Regeneração Óssea/imunologia , Humanos , Lactoferrina/imunologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacosRESUMO
Composites comprised of calcium-deficient hydroxyapatite (HAp) and biodegradable polyphosphazenes were formed via cement-type reactions at physiologic temperature. The composite precursors were produced by blending particulate hydroxyapatite precursors with 10 wt% polymer using a solvent/non-solvent technique. HAp precursors having calcium-to-phosphate ratios of 1.5 (CDH) and 1.6 (CDS) were used. The polymeric constituents were poly[bis(ethyl alanato)phosphazene] (PNEA) and poly[(ethyl alanato)(1) (p-phenylphenoxy)(1) phosphazene] (PNEA(50)PhPh(50)). The effect of incorporating the phenyl phenoxy group was evaluated as a means of increasing the mechanical properties of the composites without retarding the rates of HAp formation. Reaction kinetics and mechanistic paths were characterized by pH determination, X-ray diffraction analyses, scanning electron microscopy, and infrared spectroscopy. The mechanical properties were analyzed by compression testing. These analyses indicated that the presence of the polymers slightly reduced the rate HAp formation. However, surface hydrolysis of polymer ester groups permitted the formation of calcium salt bridges that provide a mechanism for bonding with the HAp. The compressive strengths of the composites containing PNEA(50)PhPh(50) were superior to those containing PNEA, and were comparable to those of HAp produced in the absence of polymer. The current composites more closely match the structure of bone, and are thus strongly recommended to be used as bone cements where high loads are not expected.
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Aziridinas/química , Materiais Biocompatíveis/química , Cálcio/química , Durapatita/química , Cimentos Ósseos , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Microscopia Eletrônica de Varredura/métodos , Modelos Químicos , Polímeros/química , Espectrofotometria Infravermelho/métodos , Propriedades de Superfície , Fatores de Tempo , Difração de Raios XRESUMO
The purpose of this review is to illustrate the pertinent clinical and imaging features of extremity sarcomas of uncertain differentiation, including synovial sarcoma, epithelioid sarcoma, clear-cell sarcoma, and alveolar soft part sarcoma. These tumours should be considered in the differential diagnosis when a soft-tissue mass is encountered in the extremity of an adolescent or young adult.
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Antebraço , Perna (Membro) , Imageamento por Ressonância Magnética , Sarcoma/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Adolescente , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Radiografia , Neoplasias de Tecidos Moles/diagnóstico por imagemAssuntos
Antígenos de Bactérias/sangue , Leptospira/isolamento & purificação , Leptospirose/diagnóstico , Doença Aguda , Adolescente , Adulto , Idoso , DNA Bacteriano/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina M/sangue , Leptospira/genética , Leptospira/imunologia , Leptospirose/microbiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , ChuvaAssuntos
Anticorpos Antibacterianos/sangue , Leptospira/imunologia , Leptospirose/epidemiologia , Adolescente , Adulto , Agricultura , Criança , Feminino , Humanos , Índia/epidemiologia , Leptospira/classificação , Leptospirose/microbiologia , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Ocupações/estatística & dados numéricos , Recursos Humanos em Hospital , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Sorotipagem , Médicos VeterináriosRESUMO
[figure: see text] Under the agency of N-bromosuccinimide, n-pentenyl glycosides, acetonitrile, and carboxylic acids participate in three-component-reactions that afford N-acylated glycosylamines. The procedure tolerate diverse donors, and C2-tetrachlorophthalimido and C2-azido groups effectively control anomeric stereoselectivity. Success of the procedure does not appear to depend on the acid's strength, but for an aromatic acid, substitution pattern affects the rate, while the presence of a lone pair on the para substituent inhibits the process.
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Glucosamina/análogos & derivados , Glucosamina/síntese química , Glicoproteínas/síntese química , Glicosilação , EstereoisomerismoRESUMO
Chloroquine has been the mainstay of malaria chemotherapy for the past five decades, but resistance is now widespread. Pyrimethamine or proguanil form an important component of some alternate drug combinations being used for treatment of uncomplicated Plasmodium falciparum infections in areas of chloroquine resistance. Both pyrimethamine and proguanil are dihydrofolate reductase (DHFR) inhibitors, the proguanil acting primarily through its major metabolite cycloguanil. Resistance to these drugs arises due to specific point mutations in the dhfr gene. Cross resistance between cycloguanil and pyrimethamine is not absolute. It is, therefore, important to investigate mutation rates in P. falciparum for pyrimethamine and proguanil so that DHFR inhibitor with less mutation rate is favored in drug combinations. Hence, we have compared mutation rates in P. falciparum genome for pyrimethamine and cycloguanil. Using erythrocytic stages of P. falciparum cultures, progressively drug resistant lines were selected in vitro and comparing their RFLP profile with a repeat sequence. Our finding suggests that pyrimethamine has higher mutation rate compared to cycloguanil. It enhances the degree of genomic polymorphism leading to diversity of natural parasite population which in turn is predisposes the parasites for faster selection of resistance to some other antimalarial drugs.
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Antimaláricos/farmacologia , Genoma de Protozoário , Plasmodium falciparum/efeitos dos fármacos , Animais , DNA de Protozoário/análise , DNA de Protozoário/efeitos dos fármacos , Resistência a Medicamentos/genética , Humanos , Testes de Sensibilidade Parasitária , Plasmodium falciparum/genética , Polimorfismo de Fragmento de Restrição , Proguanil , Pirimetamina/farmacologia , Sulfadoxina , Fatores de Tempo , Triazinas/farmacologiaRESUMO
Nodes, shoot tips, internodes and leaf bases (approximately 1.0 cm) excised from young vines of the flowering woody climber, Celastrus paniculatus WilId. sub. sp. paniculatus (Celastraceae) were cultured in Murashige and Skoog (MS) medium containing agar (0.6%), sucrose (3%) and varied concentrations of 6-benzyl aminopurine (BAP) and kinetin. All the explant types were regenerative and maximum number (3.6) and frequency (94%) of axillary shoot formation of (5.08 cm long) was recorded in the nodes cultured in BAP (1 mg L(-1)) after 6 weeks. Combinations of BAP (1 mg L(-1)) and indole-3-acetic acid/l-naphthalene acetic acid (0.01-1 mg L(-1); IAA/NAA) tested with nodes induced formation of less number (3 and 2.2) of shoots at same frequency (94%). All the explant types viz. node, shoot tip, internode and leaf base of in vitro derived shoots responded earlier and better in lower concentrations of BAP (0.5-2 mg L(-1)) with formation of 8, 3.1, 6.4 and 1.8 shoots respectively during the same period. In spite of the advanced and increased caulogenic responses, differences in cytokinin requirements between different explants observed during culture initiation still persisted with the nodes, shoot tips, internodes and petiole segments responding best at 0.5, 1 and 2 mg L(-1) BAP, respectively. The repeated reculture up to 10 cycles of the nodes from the shoot cultures each at 6-week intervals enabled multiplication and stocking of shoots without decline. Rooting of 3-7 cm shoot cuttings was induced in half-strength MS liquid medium containing IAA (1 mg L(-1)) with formation of 7.25 roots of 2.41 cm length within 6 weeks. Rooted plants were established at 84-96% rate in community pots without hardening, the least value (84%) being obtained with NAA- induced thick and calloid rooted plants. Four month old community potted plants were reintroduced into native forest habitats at 95% efficiency and 8 months after restoration, the plants were uniform in morphological, growth, cytological and peroxidase and esterase isozyme characteristics.
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Adenina/análogos & derivados , Celastraceae/crescimento & desenvolvimento , Plantas Medicinais/crescimento & desenvolvimento , Adenina/farmacologia , Compostos de Benzil , Celastraceae/efeitos dos fármacos , Meios de Cultura , Índia , Ácidos Indolacéticos/farmacologia , Cinetina , Ácidos Naftalenoacéticos/farmacologia , Plantas Medicinais/efeitos dos fármacos , PurinasRESUMO
[reaction: see text]n-Pentenyl ortho esters (NPOEs) and n-pentenyl glycosides (NPGs) are interconvertible glycosyl donors which are activated by reaction with halonium ions. In a series of cyclic syn-1,3-diols, NPOEs have been found to specifically glycosylate the equatorial-OH while the NPG glycosylates predominantly, but not exclusively, the axial-OH. When the cyclic diol acceptor is presented with equivalent amounts of an NPOE and an NPG in a three-component-reaction, a single, double-glycosylation product is obtained, which conforms to the foregoing preferences, presenting evidence for site-selective glycosylation.
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Alcenos/química , Glicosídeos/química , Alcenos/síntese química , Sequência de Carboidratos , Glicosídeos/síntese química , Glicosilação , Indicadores e Reagentes , Dados de Sequência MolecularRESUMO
The delivery of 37 shocks by an ICD within 20 minutes, in response to T wave oversensing during atrial flutter, resulted in several manifestations of undesirable device behavior. The generator reverted to backup mode, and disabled automatic capacitor reformation, therapy delivery, and automatic gain control. Postexplant analysis of the device revealed damage to the high voltage output section of the circuitry consistent with excessive electrical stress. In rare circumstances, multiple internal discharges can result in serious clinical anomalies in ICD behavior, and possibly in an increase in susceptibility to circuitry damage.
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Desfibriladores Implantáveis , Análise de Falha de Equipamento , Isquemia Miocárdica/complicações , Taquicardia Ventricular/terapia , Flutter Atrial/terapia , Eletrocardiografia , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/terapia , Recidiva , Processamento de Sinais Assistido por Computador , SoftwareRESUMO
Fluconazole suppositories were prepared in hydrophilic, lipophilic, and amphiphilic bases. In vitro evaluation was conducted to compare the effect of different bases on the release and permeation of fluconazole. Four types of suppository bases were evaluated; hydrophilic (polyethylene glycol, PEG), lipophilic (cocoa butter, CB; Witepsol W45 WW45), and amphiphilic (Suppocire AP SAP, a polyglycolized glyceride). The uniformity of dosage units prepared with each base was determined by ultraviolet (UV) spectroscopy. The influence of suppository base on the release of fluconazole was studied using USP dissolution apparatus I. Rate constants for each release pattern were determined and compared using a one-way analysis of variance (ANOVA) on ranks. The order of in vitro dissolution of fluconazole from the bases was as follows: PEG > (SAP = WW45) > CB. Results suggest that in vitro release of fluconazole is greater from a hydrophilic base (PEG). Preliminary permeation studies were conducted on each type of base using Franz diffusion cells. Permeation was studied through the rat rectal membrane, and normal saline was used as the receptor medium. A modified reverse-phase high-performance liquid chromatography (HPLC) method was used and validated for analyzing fluconazole. Flux values (microgram/cm2/hr) were calculated and compared using a one-way ANOVA (p < .001). The order of permeation was as follows: SAP > (PEG = WW45) > CB. The increased permeation characteristics seen with the SAP base are probably due to an alteration of the membrane characteristics due to the surface active properties of the base.