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2.
Nano Lett ; 22(24): 9900-9906, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36524710

RESUMO

Double-perovskite oxides have attracted recent attention due to their attractive functionalities and application potential. In this paper, we demonstrate the effect of dual controls, i.e., the deposition pressure of oxygen (PO2) and lattice mismatch (ε), on tuning magnetic properties in epitaxial double-perovskite Sr2FeReO6 films. In a nearly lattice matched Sr2FeReO6/SrTiO3 film, the ferrimagnetic-to-paramagnetic phase transition occurs when PO2 is reduced to 30 mTorr, probably due to the formation of Re4+ ions that replace the stoichiometric Re5+ to cause disorders of B-site ions. On the other hand, a large compressive strain or tensile strain shifts this critical PO2 to below 1 mTorr or above 40 mTorr, respectively. The observations can be attributed to the modulation of B-site ordering by epitaxial strain through affecting elemental valence. Our results provide a feasible way to expand the functional tunability of magnetic double-perovskite oxides that hold great promise for spintronic devices.

3.
Arch Psychiatr Nurs ; 46: 83-90, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37813510

RESUMO

BACKGROUND: Workplace violence is a universal phenomenon faced by employees in all industries but more so by employees working in sectors that require interpersonal contact, especially with individuals who may be violent, distressed, or vulnerable. Globally, healthcare professionals working in the emergency and psychiatric sectors are at the highest risk of workplace violence. In fact, healthcare professionals in the psychiatric setting have a higher risk rate of facing workplace violence opposed to other healthcare settings. Workplace violence can lead to adverse physical and psychological outcomes and impact the quality of care provided to patients. OBJECTIVE: This study aims to explore nurses' experiences with workplace violence and the impact of violence on nurses. Whereas the objectives of this study are to explore and analyze mental health nurses' experiences with workplace violence in Brunei Darussalam, identify and explore the impact of violence on mental health nurses, and discuss nurses' coping mechanisms following a workplace violence experience. DESIGN: Qualitative explorative study. SETTING(S): Mental Health Unit Kiarong of Raja Isteri Pengiran Anak Saleha Hospital, Brunei Darussalam. PARTICIPANTS: Nurses (n = 12). METHODS: Data was collected by conducting individual via online platforms. The interviews were carried out in English and/or Malay, the verbatim transcripts produced were transcribed in their source languages and only relevant excerpts were translated into English for the write-up. The data were analyzed utilizing thematic analysis by the researcher independently. RESULTS: This study identified three themes: Violence as a norm in the psychiatric setting, perceived impact of workplace violence, and "Talk, Report and Accept" as Coping mechanisms. CONCLUSIONS: In conclusion, it is apparent that globally workplace violence is normalized in the nursing industry, especially in the psychiatric setting. Workplace violence yields a plethora of negative long-term and short-term impacts on nurses. Despite this, workplace violence often goes unreported for numerous reasons but mainly due to the lack of changes after reporting. Nurses should be encouraged to report all instances of workplace violence by demonstrating effective changes and providing hazard pay. The management should actively attempt to reduce the risk of workplace violence by preemptively equipping nurses with the necessary training including identification of potential risks of workplace violence, effective de-escalation methods, and proper control and restraint methods.


Assuntos
Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , Violência no Trabalho , Humanos , Pacientes Internados , Violência no Trabalho/psicologia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Agressão/psicologia , Local de Trabalho/psicologia
4.
Nature ; 540(7633): 395-399, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27974754

RESUMO

Seahorses have a specialized morphology that includes a toothless tubular mouth, a body covered with bony plates, a male brood pouch, and the absence of caudal and pelvic fins. Here we report the sequencing and de novo assembly of the genome of the tiger tail seahorse, Hippocampus comes. Comparative genomic analysis identifies higher protein and nucleotide evolutionary rates in H. comes compared with other teleost fish genomes. We identified an astacin metalloprotease gene family that has undergone expansion and is highly expressed in the male brood pouch. We also find that the H. comes genome lacks enamel matrix protein-coding proline/glutamine-rich secretory calcium-binding phosphoprotein genes, which might have led to the loss of mineralized teeth. tbx4, a regulator of hindlimb development, is also not found in H. comes genome. Knockout of tbx4 in zebrafish showed a 'pelvic fin-loss' phenotype similar to that of seahorses.


Assuntos
Evolução Biológica , Proteínas de Peixes/genética , Genoma/genética , Smegmamorpha/anatomia & histologia , Smegmamorpha/genética , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/metabolismo , Animais , Sequência Conservada/genética , Proteínas de Peixes/deficiência , Deleção de Genes , Genômica , Membro Posterior/anatomia & histologia , Membro Posterior/metabolismo , Masculino , Anotação de Sequência Molecular , Família Multigênica/genética , Taxa de Mutação , Filogenia , Reprodução/fisiologia , Proteínas com Domínio T/deficiência , Proteínas com Domínio T/genética , Fatores de Tempo , Proteínas de Peixe-Zebra/deficiência , Proteínas de Peixe-Zebra/genética
5.
Arch Toxicol ; 96(1): 153-165, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34773126

RESUMO

Para-phenylenediamine (PPD) is one of the most used chemicals in oxidative hair dyes. However, its use has been associated with adverse effects on health, including contact dermatitis and other systemic toxicities. Novel PPD derivatives have been proposed as a safer replacement for PPD. This can be achieved if these molecules minimally permeate the skin and/or are easily metabolised by enzymes in the skin (e.g., N-acetyltransferase-1 (NAT-1)) into innocuous compounds before gaining systemic entry. This study investigated the detoxification pathway mediated by NAT-1 enzymes on 6 synthesized PPD analogues (namely, P1-P6) with different chemical properties, to study the role of functional groups on detoxification mechanisms in HaCaT skin cells. These compounds were carefully designed with different chemical properties (whereby the ortho position of PPD was substituted by nucleophile and electrophile groups to promote N-acetylation reactions, metabolism and clearance). Compounds P2-P4 N-acetylated at 54-49 nmol/mg/min, which is 1.6 times higher than N-acetylation of PPD, upregulated NAT-1 activity from 8-7% at 50 µM to 22-11% at 100 µM and showed 4 times higher rate of elimination (k equal to 0.141 ± 0.016-0.124 ± 0.01 h-1) and 3 times faster rate of clearance (0.172 ± 0.007-0.158 ± 0.005 h-1mgprotein-1) than PPD (0.0316 ± 0.0019 h-1, 0.0576 ± 0.003 h-1mg protein-1, respectively). The data suggest that nucleophile substituted compounds detoxify at a faster rate than PPD. Our metabolic and detoxification mechanistic studies revealed significantly higher rates of N-acetylation, NAT-1 activity and higher detoxification of P2-P4 in keratinocytes, suggesting the importance of nucleophilic groups at the ortho position in PPD to reduce toxicity of aniline-based dyes on human skin cells.


Assuntos
Dermatite Alérgica de Contato , Tinturas para Cabelo , Arilamina N-Acetiltransferase , Tinturas para Cabelo/química , Tinturas para Cabelo/metabolismo , Tinturas para Cabelo/toxicidade , Humanos , Isoenzimas , Fenilenodiaminas/metabolismo , Fenilenodiaminas/toxicidade
6.
Inorg Chem ; 60(3): 1823-1831, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33464875

RESUMO

A common challenge in Pt(IV) prodrug design is the limited repertoire of linkers available to connect the Pt(IV) scaffold with the bioactive payload. The commonly employed linkers are either too stable, leading to a linker artifact on the payload upon release, or too unstable, leading to premature release. In this study, we report the synthesis of a new class of Pt(IV) prodrugs using masked self-immolative 4-aminobenzyl linkers for controlled and traceless codrug delivery. Upon reduction of self-immolative Pt(IV) prodrugs, the detached axial ligands undergo decarboxylation and 1,6-elimination for payload release. Introduction of self-immolative linkers conferred good aqueous stability to the Pt(IV) codrug complex. Investigation revealed that efficient 1,6-elimination could be attributed to stabilization of the p-aza-quinone-methide intermediate. In particular, the self-immolative Pt(IV) prodrugs with cinnamate and coumarin derivatives were more potent than the coadministration of cisplatin with an unconjugated cinnamate or coumarin payload in vitro.


Assuntos
Antineoplásicos/química , Cisplatino/química , Compostos Organoplatínicos/química , Pró-Fármacos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Humanos , Estrutura Molecular , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/farmacologia , Pró-Fármacos/síntese química , Pró-Fármacos/farmacologia
7.
Nano Lett ; 20(3): 1890-1895, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32004008

RESUMO

We report the control of the interplane magnetic exchange coupling in CaIrO3 perovskite thin films and superlattices with SrTiO3. By analyzing the anisotropic magneto-transport data, we demonstrate that a semimetallic paramagnetic CaIrO3 turns into a canted antiferromagnetic Mott insulator at reduced dimensions. The emergence of a biaxial magneto-crystalline anisotropy indicates the canted moment responding to the cubic symmetry. Extending to superlattices and probing oxygen octahedral rotation by half-integer X-ray Braggs diffraction, a more complete picture about the canted moment evolution with interplane coupling can be understood. Remarkably, a rotation of the canted moments' easy axes by 45° is also observed by a sign reversal of the in-plane strain. These results demonstrate the robustness of anisotropic magnetoresistance in revealing quasi two-dimensional canted antiferromagnets, as well as valuable insights about quadrupolar magnetoelastic coupling, relevant for designing future antiferromagnetic spintronic devices.

8.
Nano Lett ; 20(4): 2493-2499, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32134679

RESUMO

Using interlayer interaction to control functional heterostructures with atomic-scale designs has become one of the most effective interface-engineering strategies nowadays. Here, we demonstrate the effect of a crystalline LaFeO3 buffer layer on amorphous and crystalline LaAlO3/SrTiO3 heterostructures. The LaFeO3 buffer layer acts as an energetically favored electron acceptor in both LaAlO3/SrTiO3 systems, resulting in modulation of interfacial carrier density and hence metal-to-insulator transition. For amorphous and crystalline LaAlO3/SrTiO3 heterostructures, the metal-to-insulator transition is found when the LaFeO3 layer thickness crosses 3 and 6 unit cells, respectively. Such different critical LaFeO3 thicknesses are explained in terms of distinct characteristic lengths of the redox-reaction-mediated and polar-catastrophe-dominated charge transfer, controlled by the interfacial atomic contact and Thomas-Fermi screening effect, respectively. Our results not only shed light on the complex interlayer charge transfer across oxide heterostructures but also provide a new route to precisely tailor the charge-transfer process at a functional interface.

9.
Angew Chem Int Ed Engl ; 60(24): 13405-13413, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-33755286

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, characterized by an aberrant metabolic phenotype with high metastatic capacity, resulting in poor patient prognoses and low survival rates. We designed a series of novel AuIII cyclometalated prodrugs of energy-disrupting Type II antidiabetic drugs namely, metformin and phenformin. Prodrug activation and release of the metformin ligand was achieved by tuning the cyclometalated AuIII fragment. The lead complex 3met was 6000-fold more cytotoxic compared to uncoordinated metformin and significantly reduced tumor burden in mice with aggressive breast cancers with lymphocytic infiltration into tumor tissues. These effects was ascribed to 3met interfering with energy production in TNBCs and inhibiting associated pro-survival responses to induce deadly metabolic catastrophe.


Assuntos
Antineoplásicos/metabolismo , Metformina/metabolismo , Pró-Fármacos/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Complexos de Coordenação/química , Avaliação Pré-Clínica de Medicamentos , Metabolismo Energético/efeitos dos fármacos , Ouro/química , Humanos , Metformina/química , Camundongos , Conformação Molecular , Fenformin/química , Fenformin/metabolismo , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Transplante Heterólogo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
10.
Gastroenterology ; 157(6): 1615-1629.e17, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31446059

RESUMO

BACKGROUND & AIMS: Some oncogenes encode transcription factors, but few drugs have been successfully developed to block their activity specifically in cancer cells. The transcription factor SALL4 is aberrantly expressed in solid tumor and leukemia cells. We developed a screen to identify compounds that reduce the viability of liver cancer cells that express high levels of SALL4, and we investigated their mechanisms. METHODS: We developed a stringent high-throughput screening platform comprising unmodified SNU-387 and SNU-398 liver cancer cell lines and SNU-387 cell lines engineered to express low and high levels of SALL4. We screened 1597 pharmacologically active small molecules and 21,575 natural product extracts from plant, bacteria, and fungal sources for those that selectively reduce the viability of cells with high levels of SALL4 (SALL4hi cells). We compared gene expression patterns of SALL4hi cells vs SALL4-knockdown cells using RNA sequencing and real-time polymerase chain reaction analyses. Xenograft tumors were grown in NOD/SCID gamma mice from SALL4hi SNU-398 or HCC26.1 cells or from SALL4lo patient-derived xenograft (PDX) cells; mice were given injections of identified compounds or sorafenib, and the effects on tumor growth were measured. RESULTS: Our screening identified 1 small molecule (PI-103) and 4 natural compound analogues (oligomycin, efrapeptin, antimycin, and leucinostatin) that selectively reduced viability of SALL4hi cells. We performed validation studies, and 4 of these compounds were found to inhibit oxidative phosphorylation. The adenosine triphosphate (ATP) synthase inhibitor oligomycin reduced the viability of SALL4hi hepatocellular carcinoma and non-small-cell lung cancer cell lines with minimal effects on SALL4lo cells. Oligomycin also reduced the growth of xenograft tumors grown from SALL4hi SNU-398 or HCC26.1 cells to a greater extent than sorafenib, but oligomycin had little effect on tumors grown from SALL4lo PDX cells. Oligomycin was not toxic to mice. Analyses of chromatin immunoprecipitation sequencing data showed that SALL4 binds approximately 50% of mitochondrial genes, including many oxidative phosphorylation genes, to activate their transcription. In comparing SALL4hi and SALL4-knockdown cells, we found SALL4 to increase oxidative phosphorylation, oxygen consumption rate, mitochondrial membrane potential, and use of oxidative phosphorylation-related metabolites to generate ATP. CONCLUSIONS: In a screening for compounds that reduce the viability of cells that express high levels of the transcription factor SALL4, we identified inhibitors of oxidative phosphorylation, which slowed the growth of xenograft tumors from SALL4hi cells in mice. SALL4 activates the transcription of genes that regulate oxidative phosphorylation to increase oxygen consumption, mitochondrial membrane potential, and ATP generation in cancer cells. Inhibitors of oxidative phosphorylation might be used for the treatment of liver tumors with high levels of SALL4.


Assuntos
Antineoplásicos/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Neoplasias Hepáticas/tratamento farmacológico , Fatores de Transcrição/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Fosforilação Oxidativa/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Small ; 16(50): e2004683, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33191619

RESUMO

Exploring exotic interface magnetism due to charge transfer and strong spin-orbit coupling has profound application in the future development of spintronic memory. Here, the emergence and tuning of topological Hall effect (THE) from a CaMnO3 /CaIrO3 /CaMnO3 trilayer structure are studied in detail, which suggests the presence of magnetic Skyrmion-like bubbles. First, by tilting the magnetic field direction, the evolution of the Hall signal suggests a transformation of Skyrmions into topologically-trivial stripe domains, consistent with behaviors predicted by micromagnetic simulations. Second, by varying the thickness of CaMnO3 , the optimal thicknesses for the THE signal emergence are found, which allow identification of the source of Dzyaloshinskii-Moriya interaction (DMI) and its competition with antiferromagnetic superexchange. Employing high-resolution transmission electron microscopy, randomly distributed stacking faults are identified only at the bottom interface and may avoid mutual cancellation of DMI. Last, a spin-transfer torque experiment also reveals a low threshold current density of ≈109 A m-2 for initiating the bubbles' motion. This discovery sheds light on a possible strategy for integrating Skyrmions with antiferromagnetic spintronics.

12.
Ophthalmology ; 127(8): 1064-1076, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32197910

RESUMO

PURPOSE: To examine the normative profile and determinants of macular ganglion cell-inner plexiform layer (GCIPL) thickness based on spectral-domain OCT (SD-OCT) in a nonglaucoma, multi-ethnic Asian population. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Ethnic Chinese, Malay, and Indian adults aged ≥40 years recruited from the Singapore Epidemiology of Eye Diseases Study. METHODS: All participants underwent standardized examinations. The GCIPL thickness was measured using Cirrus HD-OCT (Carl Zeiss Meditec, Dublin, CA). Participants with glaucoma or poor-quality scans were excluded. Eye-specific data were used. Associations of ocular and systemic factors with GCIPL thickness parameters were investigated using multivariable linear regression with generalized estimating equation models to account for correlation between both eyes. MAIN OUTCOME MEASURES: GCIPL thickness. RESULTS: A total of 4464 participants (7520 eyes) consisting of 1625 Chinese, 1212 Malay, and 1627 Indian adults contributed to this analysis. Average GCIPL thickness was 82.6±6.1 µm in Chinese, 81.5±6.8 µm in Malays, and 78.0±6.9 µm in Indians (P < 0.001 by analysis of variance). The 5th percentile limit of average GCIPL thickness was 72 µm in Chinese, 70 µm in Malays, and 67 µm in Indians. In multivariable analysis adjusting for age, gender, axial length, presence of cataract, OCT signal strength, disc area, hypertension, diabetes, and hyperlipidemia, eyes of Indians were observed to have 3.43 µm thinner GCIPL on average compared with Chinese (P < 0.001) and 3.36 µm thinner GCIPL compared with Malays (P < 0.001). In addition, older age (per decade; ß = -2.51), female (ß = -1.57), longer axial length (per mm; ß = -1.54), and presence of chronic kidney disease (ß = -1.49) were significantly associated with thinner average GCIPL (all P ≤ 0.008). Larger optic disc area (per mm2; ß = 0.78; P < 0.001) was associated with thicker GCIPL. These factors were consistently observed to be significant for superior and inferior hemisphere GCIPL thickness. CONCLUSIONS: GCIPL thickness profiles were significantly thinner in Indians compared with Chinese and Malays. Our findings further highlight the need of a more refined, ethnic-specific normative database for GCIPL thickness, which in turn may improve the detection and diagnosis of glaucoma in Asians.


Assuntos
Etnicidade , Glaucoma/etnologia , Vigilância da População , Células Ganglionares da Retina/patologia , Estudos Transversais , Feminino , Glaucoma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas , Disco Óptico , Singapura/epidemiologia , Tomografia de Coerência Óptica
13.
Phys Rev Lett ; 125(14): 147003, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064530

RESUMO

Infinite-layer Nd_{1-x}Sr_{x}NiO_{2} thin films with Sr doping level x from 0.08 to 0.3 are synthesized and investigated. We find a superconducting dome x between 0.12 and 0.235 accompanied by a weakly insulating behavior in both under- and overdoped regimes. The dome is akin to that in the electron-doped 214-type and infinite-layer cuprate superconductors. For x≥0.18, the normal state Hall coefficient (R_{H}) changes the sign from negative to positive as the temperature decreases. The temperature of the sign changes decreases monotonically with decreasing x from the overdoped side and approaches the superconducting dome at the midpoint, suggesting a reconstruction of the Fermi surface with the dopant concentration across the dome.

14.
Nature ; 505(7482): 174-9, 2014 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-24402279

RESUMO

The emergence of jawed vertebrates (gnathostomes) from jawless vertebrates was accompanied by major morphological and physiological innovations, such as hinged jaws, paired fins and immunoglobulin-based adaptive immunity. Gnathostomes subsequently diverged into two groups, the cartilaginous fishes and the bony vertebrates. Here we report the whole-genome analysis of a cartilaginous fish, the elephant shark (Callorhinchus milii). We find that the C. milii genome is the slowest evolving of all known vertebrates, including the 'living fossil' coelacanth, and features extensive synteny conservation with tetrapod genomes, making it a good model for comparative analyses of gnathostome genomes. Our functional studies suggest that the lack of genes encoding secreted calcium-binding phosphoproteins in cartilaginous fishes explains the absence of bone in their endoskeleton. Furthermore, the adaptive immune system of cartilaginous fishes is unusual: it lacks the canonical CD4 co-receptor and most transcription factors, cytokines and cytokine receptors related to the CD4 lineage, despite the presence of polymorphic major histocompatibility complex class II molecules. It thus presents a new model for understanding the origin of adaptive immunity.


Assuntos
Evolução Molecular , Genoma/genética , Tubarões/genética , Animais , Cálcio/metabolismo , Linhagem da Célula/imunologia , Proteínas de Peixes/classificação , Proteínas de Peixes/genética , Deleção de Genes , Genômica , Imunidade Celular/genética , Anotação de Sequência Molecular , Dados de Sequência Molecular , Osteogênese/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Filogenia , Estrutura Terciária de Proteína/genética , Tubarões/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Fatores de Tempo , Vertebrados/classificação , Vertebrados/genética , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento
15.
Nature ; 513(7518): 375-381, 2014 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-25186727

RESUMO

Cichlid fishes are famous for large, diverse and replicated adaptive radiations in the Great Lakes of East Africa. To understand the molecular mechanisms underlying cichlid phenotypic diversity, we sequenced the genomes and transcriptomes of five lineages of African cichlids: the Nile tilapia (Oreochromis niloticus), an ancestral lineage with low diversity; and four members of the East African lineage: Neolamprologus brichardi/pulcher (older radiation, Lake Tanganyika), Metriaclima zebra (recent radiation, Lake Malawi), Pundamilia nyererei (very recent radiation, Lake Victoria), and Astatotilapia burtoni (riverine species around Lake Tanganyika). We found an excess of gene duplications in the East African lineage compared to tilapia and other teleosts, an abundance of non-coding element divergence, accelerated coding sequence evolution, expression divergence associated with transposable element insertions, and regulation by novel microRNAs. In addition, we analysed sequence data from sixty individuals representing six closely related species from Lake Victoria, and show genome-wide diversifying selection on coding and regulatory variants, some of which were recruited from ancient polymorphisms. We conclude that a number of molecular mechanisms shaped East African cichlid genomes, and that amassing of standing variation during periods of relaxed purifying selection may have been important in facilitating subsequent evolutionary diversification.


Assuntos
Ciclídeos/classificação , Ciclídeos/genética , Evolução Molecular , Especiação Genética , Genoma/genética , África Oriental , Animais , Elementos de DNA Transponíveis/genética , Duplicação Gênica/genética , Regulação da Expressão Gênica/genética , Genômica , Lagos , MicroRNAs/genética , Filogenia , Polimorfismo Genético/genética
16.
Clin Exp Ophthalmol ; 48(9): 1210-1218, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32734654

RESUMO

IMPORTANCE: Evidence-based guidelines are essential for glaucoma screening to work effectively. BACKGROUND: To derive a vertical cup-to-disc ratio (VCDR) cut-off for glaucoma screening in a multi-ethnic Asian population. DESIGN: The Singapore Epidemiology of Eye Diseases (SEED) study is a population-based study conducted from 2004 to 2011 in a single tertiary care research institute. PARTICIPANTS: SEED comprised of 10 033 Chinese, Malay and Indian adults aged ≥40 (response rate 75.6%). After excluding participants with a history of glaucoma medication or surgery, 9673 participants were included for analysis. METHODS: A systematic eye examination, which included applanation tonometry, visual field testing, gonioscopy and dilated fundus examination was conducted. MAIN OUTCOME MEASURE: Diagnosis of glaucoma. RESULTS: The distribution of VCDR and VCDR asymmetry were relatively homogenous in this multi-ethnic Asian population, with a 97.5th percentile value of 0.67 and 0.17, respectively. In the absence of more definite signs of glaucoma, VCDR ≥0.60 and VCDR asymmetry ≥0.20 provided the best balance between sensitivity (95.1%) and specificity (90.9%) in detecting glaucoma. For larger optic disc (≥2.0 mm), VCDR ≥0.65 with VCDR asymmetry ≥0.20 provided the best balance between sensitivity (84.8%) and specificity (93.2%). CONCLUSION AND RELEVANCE: Overall, VCDR ≥0.60 with VCDR ≥0.20 asymmetry provides a good balance between sensitivity and specificity in detecting glaucoma. For larger optic disc, VCDR ≥0.65 should be considered instead to mitigate against false-referrals due to larger physiological disc cupping. Our findings may act as a reference to populations with similar VCDR distribution.


Assuntos
Glaucoma , Disco Óptico , Adulto , Técnicas de Diagnóstico Oftalmológico , Humanos , Pressão Intraocular , Tonometria Ocular , Testes de Campo Visual
17.
Psychooncology ; 28(1): 147-153, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30346074

RESUMO

OBJECTIVES: Patient-reported outcomes (PROs) in high-income countries (HICs) suggest that physical, emotional, and psychological needs are important in cancer care. To date, there have been few inconsistent descriptions of PROs in low-income and middle-income Asian countries. Using a standard questionnaire developed by the International Consortium for Health Outcomes Measurement (ICHOM), we compared the perceived importance of PROs between patients in Malaysia and those in HICs and between clusters of Malaysian women. METHODS: Breast cancer patients were recruited from three Malaysian hospitals between June and November 2017. We compared the proportion of patients who rated PROs as very important (scored 7-9 on a 9-point Likert scale) between Malaysian patients and data collected from patients in HICs via the ICHOM questionnaire development process, using logistic regression. A two-step cluster analysis explored differences in PROs among Malaysian patients. RESULTS: The most important PROs for both cohorts were survival, overall well-being, and physical functioning. Compared with HIC patients (n = 1177), Malaysian patients (n = 969) were less likely to rate emotional (78% vs 90%), cognitive (76% vs 84%), social (72% vs 81%), and sexual (30% vs 56%) functioning as very important outcomes (P < 0.001). Cluster analysis suggests that older, parous, Malaysian women, who were less likely to have received breast reconstructive surgery, were more likely to rate body image and satisfaction with the breast as very important outcomes. CONCLUSION: Taking into account the differences in PROs by cultural and socioeconomic settings could improve patient expectation of services and refine the assessment of cancer care outcomes.


Assuntos
Neoplasias da Mama/psicologia , Sobreviventes de Câncer/psicologia , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida/psicologia , Adaptação Psicológica , Adulto , Imagem Corporal/psicologia , Neoplasias da Mama/terapia , Sobreviventes de Câncer/estatística & dados numéricos , Estudos Transversais , Países Desenvolvidos , Feminino , Humanos , Renda/estatística & dados numéricos , Malásia , Pessoa de Meia-Idade , Autoimagem , Fatores Socioeconômicos , Inquéritos e Questionários
19.
Bioconjug Chem ; 29(7): 2176-2180, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29944344

RESUMO

A new glucose-responsive insulin delivery system is fabricated using biomimetic peptide coacervates derived from the Humboldt squid (Dosidicus Gigas) beak. Both insulin and glucose oxidase are coencapsulated within coacervate microdroplets. The glucose oxidase quickly responds to increasing glucose levels to generate a local acidic environment, thereby rapidly triggering the dissociation of pH-sensitive coacervates to release the insulin cargo. The rate of insulin release is dependent on the glucose level, increases under hyperglycemic conditions, and decreases under normoglycemic conditions. This glucose responsiveness mimics pancreatic ß-cell function by releasing insulin according to glucose levels.


Assuntos
Cápsulas/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Insulina/administração & dosagem , Peptídeos/uso terapêutico , Animais , Bico/química , Cápsulas/química , Decapodiformes , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Glucose/metabolismo , Glucose/farmacologia , Glucose Oxidase , Humanos , Concentração de Íons de Hidrogênio , Peptídeos/efeitos dos fármacos
20.
Brain Behav Immun ; 62: 35-40, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27810376

RESUMO

The blood-brain barrier (BBB) plays an important role in the clinical expression of neuropsychiatric symptoms during systemic illness in health and neurological disease. Evidence from in vitro and preclinical in vivo studies indicate that systemic inflammation impairs blood-brain barrier function. In order to investigate this hypothesis, we evaluated the association between systemic inflammatory markers (leucocytes, erythrocyte sedimentation rate and C-reactive protein) and BBB function (cerebrospinal fluid/serum albumin ratio) in 1273 consecutive lumbar punctures. In the absence of cerebrospinal fluid (CSF) abnormality, systemic inflammation did not affect the CSF/serum albumin ratio. When CSF abnormality was present, systemic inflammation significantly predicted the CSF/serum albumin ratio. Amongst the systemic inflammatory markers, C-reactive protein was the predominant driver of this effect. Temporal analysis in this association study suggested causality. In conclusion, the diseased BBB has an increased susceptibility to systemic inflammation.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Proteína C-Reativa/metabolismo , Inflamação/fisiopatologia , Leucócitos/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Sedimentação Sanguínea , Barreira Hematoencefálica/metabolismo , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Albumina Sérica/metabolismo
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