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1.
Sci Rep ; 8(1): 12538, 2018 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-30135446

RESUMO

Cell penetrating peptides (CPPs) offer great potential to deliver therapeutic molecules to previously inaccessible intracellular targets. However, many CPPs are inefficient and often leave their attached cargo stranded in the cell's endosome. We report a versatile platform for the isolation of peptides delivering a wide range of cargos into the cytoplasm of cells. We used this screening platform to identify multiple "Phylomer" CPPs, derived from bacterial and viral genomes. These peptides are amenable to conventional sequence optimization and engineering approaches for cell targeting and half-life extension. We demonstrate potent, functional delivery of protein, peptide, and nucleic acid analog cargos into cells using Phylomer CPPs. We validate in vivo activity in the cytoplasm, through successful transport of an oligonucleotide therapeutic fused to a Phylomer CPP in a disease model for Duchenne's muscular dystrophy. This report thus establishes a discovery platform for identifying novel, functional CPPs to expand the delivery landscape of druggable intracellular targets for biological therapeutics.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Animais , Bacteriófago T7 , Biotinilação , Células CHO , Carbono-Nitrogênio Ligases/genética , Carbono-Nitrogênio Ligases/metabolismo , Peptídeos Penetradores de Células/genética , Peptídeos Penetradores de Células/toxicidade , Dicroísmo Circular , Cricetulus , Modelos Animais de Doenças , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Distrofia Muscular de Duchenne/tratamento farmacológico , Biblioteca de Peptídeos , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
2.
J Insect Sci ; 17(5)2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28922900

RESUMO

Nutrients in breeding sites are critical for the survival and development of malaria mosquitoes, having a direct impact on vectorial capacity. Yet, there is a limited understanding about the natural larval diet and its impact on the individual fitness of mosquitoes. Recent studies have shown that gravid Anopheles arabiensis Patton (Diptera: Culicidae) are attracted by and oviposit in grass-associated habitats. The pollen provided by these grasses is a potential source of nutrients for the larvae. Here, we assess the effect of Typha latifolia L. (Poales: Typhaceae), Echinochloa pyramidalis Lamarck, Pennisetum setaceum Forsskål, and Zea mays L. pollen on larval survival and rate of development in An. arabiensis under laboratory conditions. In addition, we characterize the carbon to nitrogen ratio and the size of pollen grains as a measure of diet quality. Carbon-rich pollen with a small grain size (T. latifolia and P. setaceum; 9.7 ± 0.3 × 103 and 5.5 ± 0.2 × 104 µm3, respectively) resulted in enhanced rates of development of An. arabiensis. In contrast, the larva fed on the nitrogen-rich control diet (TetraMin) was slower to develop, but demonstrated the highest larval survival. Larvae fed on carbon-rich and large-grained Z. mays pollen (4.1 ± 0.2 × 105 µm3) survived at similar levels as those fed on the control diet and also took a longer time to develop compared with larvae fed on the other pollens. While males and females did not appear to develop differently on the different pollen diets, males consistently emerged faster than their female counterparts. These results are discussed in relation to integrated vector management.


Assuntos
Anopheles/fisiologia , Dieta , Longevidade , Valor Nutritivo , Poaceae , Pólen/química , Typhaceae/química , Animais , Anopheles/crescimento & desenvolvimento , Feminino , Larva/crescimento & desenvolvimento , Masculino
3.
J Heart Valve Dis ; 23(3): 259-70, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25296447

RESUMO

BACKGROUND AND AIM OF THE STUDY: Native, allograft, xenograft and bioprosthetic semilunar valves are all susceptible to calcific degeneration. However, intrinsic differences in baseline calcium and phosphorus tissue concentrations within mammalian normal valve structural components (e.g., cusps, sinus, vessel wall) additionally subdivided by tripartite regions (e.g., right-, left- and non-coronary leaflets) have never been systematically measured and reported. It was originally hypothesized that variations in normative tissue concentrations of calcium and phosphorus may correspond to subsequent clinical patterns of acquired dystrophic calcification; decellularization was also expected to reduce the tissue concentrations of these elements. METHODS: Native semilunar valves were freshly harvested from 12 juvenile sheep. Half of the valves were decellularized (six aortic and six pulmonary), while the other valves were flash-frozen at -80 degrees C within minutes of euthanasia as native valves. Elemental calcium and phosphorus concentrations were measured in the great vessels, sinus walls and cusps using inductively coupled plasma optical emission spectrometry (ICP-OES), and analyzed with non-parametric statistical tests. RESULTS: Calcium concentrations (microg/mg tissue; median (range) were similar in aortic native cusps (0.37 (0.21)), sinus walls (0.37 (0.09)) and aorta (0.37 (0.08)) (p = 0.8298). Pulmonary calcium concentrations were similar in cusps, but 10-25% higher in the native sinus (p = 0.0018) and pulmonary artery (p < 0.0001) compared to analogous aortic structures. All cusps had higher phosphorus concentrations than their respective conduit tissues. No tripartite regional variations were observed. Decellularization did not reduce the calcium content of cusps, but removed 50-55% of vessel and sinus wall calcium. However, up to 85% of phosphorus was removed from all valve tissues (p < 0.001). CONCLUSION: There were no significant differences in normal tissue concentrations of calcium between aortic valve functional structures, and no semilunar tripartite regional differences in either semilunar valve complex. Thus, the distribution of baseline tissue calcium content of healthy young valves is not inherently predictive of selective or asymmetric anatomical patterns of valve degenerative calcification. Native semilunar cusps contain the highest phosphorus concentrations. Decellularization reduces all elemental concentrations except for cuspal calcium.


Assuntos
Valva Aórtica/química , Cálcio/análise , Fósforo/análise , Valva Pulmonar/química , Aloenxertos , Animais , Aorta/química , Aorta/citologia , Valva Aórtica/citologia , Bioprótese , Calcinose/prevenção & controle , Criopreservação , DNA/isolamento & purificação , Próteses Valvulares Cardíacas , Xenoenxertos , Artéria Pulmonar/química , Artéria Pulmonar/citologia , Valva Pulmonar/citologia , Ovinos
4.
Parasit Vectors ; 4: 183, 2011 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-21936953

RESUMO

BACKGROUND: Native mosquito repellent plants have a good potential for integrated mosquito control in local settings. Ocimum forskolei, Lamiaceae, is used in Eritrea as a spatial mosquito repellent inside houses, either through crushing fresh plants or burning dry plants. We verified whether active repellent compounds could be identified using gas-chromatography coupled electroantennogram recordings (GC-EAD) with headspace extracts of crushed plants. RESULTS: EAD active compounds included (R)-(-)-linalool, (S)-(+)-1-octen-3-ol, trans-caryophyllene, naphthalene, methyl salicylate, (R)-(-)-α-copaene, methyl cinnamate and (E)-ocimene. Of these compounds (R)-(-)-linalool, methyl cinnamate and methyl salicylate reduced landing of female Aedes aegypti on human skin-odor baited tubes. The latter two are novel mosquito repellent compounds. CONCLUSIONS: The identification of mosquito repellent compounds contributes to deciphering the mechanisms underlying repulsion, supporting the rational design of novel repellents. The three mosquito repellent compounds identified in this study are structurally dissimilar, which may indicate involvement of different sensory neurons in repulsion. Repulsion may well be enhanced through combining different repellent plants (or their synthetic mimics), and can be a locally sustainable part in mosquito control efforts.


Assuntos
Aedes/efeitos dos fármacos , Repelentes de Insetos/química , Ocimum/química , Odorantes/análise , Extratos Vegetais/química , Compostos Orgânicos Voláteis/química , Aedes/fisiologia , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Repelentes de Insetos/farmacologia , Masculino , Controle de Mosquitos , Extratos Vegetais/farmacologia , Compostos Orgânicos Voláteis/farmacologia
5.
PLoS One ; 6(5): e20067, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21603645

RESUMO

Acquired immunodeficiency syndrome and tuberculosis (TB) are two of the world's most devastating diseases. The first vaccine the majority of infants born in Africa receive is Mycobacterium bovis bacillus Calmette-Guérin (BCG) as a prevention against TB. BCG protects against disseminated disease in the first 10 years of life, but provides a variable protection against pulmonary TB and enhancing boost delivered by recombinant modified vaccinia virus Ankara (rMVA) expressing antigen 85A (Ag85A) of M. tuberculosis is currently in phase IIb evaluation in African neonates. If the newborn's mother is positive for human immunodeficiency virus type 1 (HIV-1), the baby is at high risk of acquiring HIV-1 through breastfeeding. We suggested that a vaccination consisting of recombinant BCG expressing HIV-1 immunogen administered at birth followed by a boost with rMVA sharing the same immunogen could serve as a strategy for prevention of mother-to-child transmission of HIV-1 and rMVA expressing an African HIV-1-derived immunogen HIVA is currently in phase I trials in African neonates. Here, we aim to develop a dual neonate vaccine platform against HIV-1 and TB consisting of BCG.HIVA administered at birth followed by a boost with MVA.HIVA.85A. Thus, mMVA.HIVA.85A and sMVA.HIVA.85A vaccines were constructed, in which the transgene transcription is driven by either modified H5 or short synthetic promoters, respectively, and tested for immunogenicity alone and in combination with BCG.HIVA(222). mMVA.HIVA.85A was produced markerless and thus suitable for clinical manufacture. While sMVA.HIVA.85A expressed higher levels of the immunogens, it was less immunogenic than mMVA.HIVA.85A in BALB/c mice. A BCG.HIVA(222)-mMVA.HIVA.85A prime-boost regimen induced robust T cell responses to both HIV-1 and M. tuberculosis. Therefore, proof-of-principle for a dual anti-HIV-1/M. tuberculosis infant vaccine platform is established. Induction of immune responses against these pathogens soon after birth is highly desirable and may provide a basis for lifetime protection maintained by boosts later in life.


Assuntos
Vacinas contra a AIDS/farmacologia , Vacinas contra a Tuberculose/farmacologia , Vacinas contra a AIDS/síntese química , Vacinas contra a AIDS/genética , África , Animais , Avaliação Pré-Clínica de Medicamentos , HIV-1/imunologia , Humanos , Lactente , Recém-Nascido , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/imunologia , Regiões Promotoras Genéticas , Linfócitos T/imunologia , Transcrição Gênica , Transgenes , Vacinas contra a Tuberculose/síntese química
6.
Br J Psychiatry Suppl ; 51: s76-81, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18055942

RESUMO

BACKGROUND: The nosological status of auditory hallucinations in non-clinical samples is unclear. AIMS: To investigate the functional neural basis of non-clinical hallucinations. METHOD: After selection from 1206 people, 68 participants of high, medium and low hallucination proneness completed a task designed to elicit verbal hallucinatory phenomena under conditions of stimulus degradation. Eight subjects who reported hearing a voice when none was present repeated the task during functional imaging. RESULTS: During the signal detection task, the high hallucination-prone participants reported a voice to be present when it was not (false alarms) significantly more often than the average or low participants (P<0.03, d.f.=2). On functional magnetic resonance imaging, patterns of activation during these false alarms showed activation in the superior and middle temporal cortex (P<0.001). CONCLUSIONS: Auditory hallucinatory experiences reported in non-clinical samples appear to be mediated by similar patterns of cerebral activation as found during hallucinations in schizophrenia.


Assuntos
Transtornos da Percepção Auditiva/fisiopatologia , Alucinações/fisiopatologia , Lobo Temporal/fisiopatologia , Estimulação Acústica/métodos , Adolescente , Adulto , Transtornos da Percepção Auditiva/psicologia , Mapeamento Encefálico/métodos , Feminino , Alucinações/psicologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Fumar Maconha/psicologia , Tempo de Reação , Psicologia do Esquizofrênico , Detecção de Sinal Psicológico
7.
J Ethnopharmacol ; 95(1): 95-101, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15374613

RESUMO

An ethnobotanical study was conducted to find plants traditionally used against nuisance insects in three regions of Eritrea: highland, eastern escarpment and wet lowland. Six plants were collected, two of them were reported to be used against mosquitoes (Ocimum forskolei, Lamiaceae and Nicotiana glauca, Solanaceae), two others against fleas (Salvia shimperi, Lamiaceae and Otostegia integrifolia, Lamiaceae) and Neorautanenia mitis (Fabaceae) and Calpurnea aurea (Fabaceae) against animal lice. The effect of fresh leaves and shoots of O. forskolei hanging on walls at the head and foot of beds was tested in Eritrea against Anopheles arabiensis and 53% reduction in mean number of mosquitoes per house was achieved. Blood meals of mosquitoes collected from houses and pit shelters were analysed to determine whether biting diversion occurred due to the use of plants in the houses. No diversion of biting was observed to goats, which are abundant in the test area. Hot water distillates of N. glauca, S. schimperi and O. integrifolia were tested against An. gambiae s.s. in the laboratory using a Hemotek membrane blood feeder with pig skin replacing the parafilm membrane. The approximate doses in microl/cm(2) for 50% repellency with the extracts of S. schimperi, N. glauca and O. integrifolia were 0.97, 1.72 and 2.44, respectively. Even though the plants only achieved partial protection, they have a potential for widespread use as a complement to other control methods.


Assuntos
Etnobotânica/métodos , Mordeduras e Picadas de Insetos/prevenção & controle , Repelentes de Insetos/farmacologia , Insetos/efeitos dos fármacos , Medicinas Tradicionais Africanas , Ocimum , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Eritreia , Humanos , Repelentes de Insetos/isolamento & purificação , Repelentes de Insetos/uso terapêutico , Pessoa de Meia-Idade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta , Brotos de Planta
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