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1.
J Cannabis Res ; 4(1): 1, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34980266

RESUMO

BACKGROUNDS: Cannabis sativa L. produces at least 120 cannabinoids. Although genetic variation is the main factor in cannabinoid production, the effects of short-term environmental stresses in the early flowering stage remains largely unknown. METHODS: To investigate the effects of short-term environmental stresses on the onset of cannabinoid production in young immature flowers, a hemp variety, Green-Thunder (5-8% CBD/mg of dry weight), was treated with mechanical damage, insect herbivory, extreme heat, or drought stress for 5-7 days during the first 2 weeks of flowering. Three hemp tissues, including flowers, leaves, and stems, were collected from hemp grown under these stress conditions at multiple time points during the first 2 weeks after transition to the short photoperiod and analyzed using high pressure liquid chromatography to quantify phytocannabinoids including cannabigerolic acid (CBGA), cannabigerol (CBG), cannabidiolic acid (CBDA), cannabidiol (CBD), Δ-tetrahydrocannabinolic acid (THCA), Δ-tetrahydrocannabinol (THC), and cannabinol (CBN). RESULTS: The 5 days of mechanical wounding did not affect the production of any of the cannabinoids during the initial stage of flowering. However, after 5 days of herbivore treatment, there was a significant difference in concentration between day 1 and day 6 of CBGA (control: 308 µg/g; treatment - 24 µg/g), CBG (control: 69 µg/g; treatment: 52 µg/g), and CBD (control: 755 µg/g; treatment: 194 µg/g) between the control and treatment plants. The 7 days of heat treatment at 45-50 oC significantly reduced the production of CBGA during this observed window (control: 206 µg/g; treatment: 182 µg/g) and CBG (control: 21 µg/g; treatment: - 112 µg/g). Notably, the largest change was observed after 7 days of drought stress, when plants showed a 40% greater accumulation of CBG (control: 336 µg/g; treatment: 622 µg/g), and a significant decrease (70-80%) in CBD (control: 1182 µg/g; treatment: 297 µg/g) and THC amounts (control: 3927 µg/g; treatment: 580 µg/g). CONCLUSIONS: Although this observation is limited in the early flowering stage, the common field stresses are adequate to induce changes in the cannabinoid profiles, particularly drought stress being the most impactful stress for hemp flower initiation with the altering the cannabinoid production by decreasing CBD and THC accumulation while increasing CBG by 40%.

2.
Int J Tuberc Lung Dis ; 25(4): 305-314, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33762075

RESUMO

BACKGROUND: Treatment for TB is lengthy and toxic, and new regimens are needed.METHODS: Participants with pulmonary drug-susceptible TB (DS-TB) were randomised to receive: 200 mg pretomanid (Pa, PMD) daily, 400 mg moxifloxacin (M) and 1500 mg pyrazinamide (Z) for 6 months (6Pa200MZ) or 4 months (4Pa200MZ); 100 mg pretomanid daily for 4 months in the same combination (4Pa100MZ); or standard DS-TB treatment for 6 months. The primary outcome was treatment failure or relapse at 12 months post-randomisation. The non-inferiority margin for between-group differences was 12.0%. Recruitment was paused following three deaths and not resumed.RESULTS: Respectively 4/47 (8.5%), 11/57 (19.3%), 14/52 (26.9%) and 1/53 (1.9%) DS-TB outcomes were unfavourable in patients on 6Pa200MZ, 4Pa200MZ, 4Pa100MZ and controls. There was a 6.6% (95% CI -2.2% to 15.4%) difference per protocol and 9.9% (95%CI -4.1% to 23.9%) modified intention-to-treat difference in unfavourable responses between the control and 6Pa200MZ arms. Grade 3+ adverse events affected 68/203 (33.5%) receiving experimental regimens, and 19/68 (27.9%) on control. Ten of 203 (4.9%) participants on experimental arms and 2/68 (2.9%) controls died.CONCLUSION: PaMZ regimens did not achieve non-inferiority in this under-powered trial. An ongoing evaluation of PMD remains a priority.


Assuntos
Antituberculosos , Pirazinamida , Tuberculose , Humanos , Antituberculosos/uso terapêutico , Quimioterapia Combinada , Moxifloxacina , Nitroimidazóis , Resultado do Tratamento , Tuberculose/tratamento farmacológico
3.
Sci Rep ; 9(1): 10481, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324859

RESUMO

Cannabis sativa, also known as marijuana or hemp, produces a non-psychoactive compound cannabidiol (CBD). To investigate the defensive role of CBD, a feeding preference assay was performed with tobacco hornworm Manduca sexta. The larvae clearly show feeding preference towards the Cannabis tissue containing low CBD over high CBD. While the larva avoided the high CBD diet, we investigated detrimental effects of CBD in the insects' diet. Contrasted to the performance on low CBD-infused artificial diet (AD), larvae reared on the high CBD diet suffer significantly reduced growth and increased mortality. Through testing different carriers, we found that the increase of EtOH in the diet is negatively correlated with insect development and behaviors. Notably, CBD treatment significantly improved ethanol-intoxicated larval survival rate by 40% and also improved diet searching activity, resulting in increased diet consumption. Electrophysiology results revealed that the CBD-treated ganglia had delayed but much larger response with electric stimuli in comparison to the larvae reared on AD only and EtOH-added diet. Our results show CBDs' defensive role against pest insects, which suggests its possible use as an insecticide. We also provide evidence that CBD alleviates alcohol-induced stress; consequently, improving the performance and viability of M. sexta larvae.


Assuntos
Canabidiol/farmacologia , Etanol/farmacologia , Inseticidas/farmacologia , Manduca/efeitos dos fármacos , Animais , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Etanol/antagonistas & inibidores , Gânglios dos Invertebrados/efeitos dos fármacos , Larva/efeitos dos fármacos , Masculino
4.
Public Health Action ; 9(1): 24-31, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30963039

RESUMO

SETTING: In 2011, the South African government began to offer isoniazid preventive therapy (IPT) through the public health system to presumptively treat latent tuberculous infection (LTBI) among people living with human immunodeficiency virus. OBJECTIVE: To describe IPT perceptions and experiences in three Zulu communities in KwaZulu-Natal Province, South Africa. DESIGN: Using a combination of community-based research and ethnographic methods, we undertook 17 individual and group interviews between October 2014 and May 2015. Interviews transcripts were analysed using qualitative content analysis and validated with grass-roots community advisors. RESULTS: Participants reported multiple ways in which IPT was perceived as dangerous: when costs related to pill collection or consumption were unsustainable, or when daily pill consumption resulted in stigma or was seen to introduce excess dirt or toxins, 'ukungcola', in the body. Theories on dirt are evoked to describe how IPT was perceived as 'matter out of place' when given to people who believed themselves to be healthy, suggesting that under the current TB aetiological model in Zulu culture, 'prevention as tablet' may not fit. CONCLUSION: Implementing IPT without understanding the realities of community stakeholders can unintentionally undermine TB control efforts by worsening the situation for people who already encounter numerous daily problems.

5.
Int J Tuberc Lung Dis ; 22(5): 40-45, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29665952

RESUMO

The paediatric tuberculosis (TB) prevention and treatment landscape is moving into a new and exciting era, with knowledge from clinical trials offering real benefit to children. Community engagement is key to optimising the success of these trials. However, the clinical profile, epidemiology and social perceptions for paediatric multidrug-resistant TB (MDR-TB) complicate the operationalisation of this community engagement. We reflect on a diversity of recent experiences attempting to implement this type of research and the community engagement around it. We describe four recommendations and argue that these should guide the implementation of the community engagement agenda in the new landscape of paediatric MDR-TB clinical trials. Specifically, we argue for 1) dynamic, long-term continuity in community engagement platforms; 2) tiers of TB and research literacy; 3) multiple separate and joint platforms for holding 'stakes'; and 4) addressing the social/structural implications of family participation. We conclude that community-level stakeholders, such as health workers, parents and children, are willing to collaborate in paediatric MDR-TB clinical trials. Using these recommendations, there is considerable opportunity for effective community engagement in this new era of paediatric MDR-TB research.


Assuntos
Antituberculosos/uso terapêutico , Participação da Comunidade , Consentimento dos Pais/ética , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Criança , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos
6.
Vox Sang ; 112(8): 780-787, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28960317

RESUMO

BACKGROUND AND OBJECTIVES: Vital sign observations should be monitored before, during and after transfusion to enable adverse events to be identified, but surveys in the UK show poor compliance with good practice. At the Oxford University Hospitals, there are two electronic bedside processes for recording observations; BloodTrack Tx (Haemonetics Corp.), the routine electronic transfusion process and a locally developed process, the System for Electronic Nursing Documentation (SEND) with integrated 'track and trigger' calculation for monitoring vital signs. The purpose of this study was to evaluate the conduct of patient observation monitoring for blood transfusion using two electronic bedside processes. MATERIALS AND METHODS: This study examined the observations recorded during 200 single red cell unit transfusions. RESULTS: 186/200 (93%) transfusions had pretransfusion observations recorded using BloodTrack Tx. Mid-transfusion checks were performed during 133/200 (67%) of transfusions, of these checks most (87/200 (44%)) were documented as 'no apparent change' in observations. End transfusion observations were performed using BloodTrack Tx in 178/200 (89%). Both systems were frequently used, and staff had a preference for using SEND first for documenting the pretransfusion observations (102/116 (88%)) and at the end of a transfusion (75/115 (65%)). CONCLUSION: Electronic bedside systems result in improved monitoring of transfusion-related observations compared to manual processes based on data from UK surveys. There is increasing use of electronic systems in clinical practice; linkage between these two systems would prevent wasteful duplication of observations and could provide improved early warning of adverse events to transfusion compared to manual processes.


Assuntos
Transfusão de Sangue , Reação Transfusional/diagnóstico , Registros Eletrônicos de Saúde , Hospitais Universitários , Humanos , Observação , Autorrelato
7.
Nanotechnology ; 23(45): 455101, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23064678

RESUMO

We have fabricated porous membranes using a parylene encapsulated vertically aligned forest of multi-walled carbon nanotubes (MWCNTs, about 7 nm inner diameter). The transport of charged particles in electrolyte through these membranes was studied by applying electric field and pressure. Under an electric field in the range of 4.4 × 10(4) V m(-1), electrophoresis instead of electroomosis is found to be the main mechanism for ion transport. Small molecules and 5 nm gold nanoparticles can be driven through the membranes by an electric field. However, small biomolecules, like DNA oligomers, cannot. Due to the weak electric driving force, the interactions between charged particles and the hydrophobic CNT inner surface play important roles in the transport, leading to enhanced selectivity for small molecules. Simple chemical modification on the CNT ends also induces an obvious effect on the translocation of single strand DNA oligomers and gold nanoparticles under a modest pressure (<294 Pa).


Assuntos
Íons/química , Nanotubos de Carbono/química , Polímeros/química , Xilenos/química , DNA/química , Eletrólitos/química , Eletroforese/instrumentação , Desenho de Equipamento , Ouro/química , Nanopartículas/química , Nanotubos de Carbono/ultraestrutura , Tamanho da Partícula , Porosidade , Pressão
8.
Plant Dis ; 94(11): 1348-1354, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30743624

RESUMO

A previously unidentified plant Rhabdovirus sp. associated with a blotchy mosaic symptom of soybean (Glycine max), prevalent in the lower-lying, warmer soybean production areas of South Africa, was isolated and partially characterized. The virus was shown to be transmitted by mechanical inoculation and at least one species of leafhopper (Peragallia caboverdensis Lindberg (Cicadellidae, Agalliinae)). To determine the morphology and virion size, as well as intercellular accumulation, negative-stained preparations or embedded ultrathin sections of infected plant samples were observed under a transmission electron microscope. The distribution of the virions within the cytoplasm and its bullet-shaped morphology and size (338 to 371 nm by 93 nm) suggested that it is a putative member of the genus Cytorhabdovirus. Degenerate primers designed to a conserved region of the polymerase gene of a number of Rhabdovirus spp. were used in reverse-transcriptase polymerase chain reaction with total RNA from symptomatic plants as template. Amplicons were sequenced and compared with related sequences available on GenBank. The analysis confirmed that the virus was related to Cytorhabdovirus spp., with the highest nucleotide similarity being 60.7% with Northern cereal mosaic virus. The particle morphology, typical virion accumulation in the cytoplasm of infected cells, nucleotide sequence similarity with that of other plant Rhabdovirus spp., and unique symptoms on soybean suggest that the virus is a previously unknown Cytorhabdovirus sp., for which we propose the name Soybean blotchy mosaic virus (SbBMV).

9.
Am J Public Health ; 87(12): 2063-7, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9431308

RESUMO

This paper argues that if the federal government is to successfully protect the public from the adverse effects of environmental noise, its policies will need to be informed by a scientific understanding of the psychological and social factors that determine when noise results in annoyance and when noise may affect health as an environmental stressor. The overreliance of federal agencies on mathematical modeling of average group responses to physical noise levels is discussed as oversimplifying and limiting the understanding of noise effects in crucial ways. The development of a more sophisticated information base is related to policy needs, such as the need to make accurate predictions about the annoyance of particular communities, the need to understand relationships between public participation in noise abatement efforts and annoyance, and the need to identify populations that may be susceptible to stress-related health effects.


Assuntos
Saúde Ambiental/legislação & jurisprudência , Política de Saúde/legislação & jurisprudência , Ruído/prevenção & controle , Saúde Pública/legislação & jurisprudência , Participação da Comunidade , Necessidades e Demandas de Serviços de Saúde , Humanos , Concentração Máxima Permitida , Pesquisa , Estados Unidos , United States Environmental Protection Agency
10.
Am Psychol ; 51(2): 143-50, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8746149

RESUMO

A research-based, policy-directed argument is made for increasing psychologists' involvement in environmental noise research. Federal policy problems are related to the government's reliance on limited data from a dose-response model and the neglect of key psychological issues such as individual differences in reactions to environmental noise, the psychological factors that mediate annoyance and that identify subgroups that may need protection from stress-related health effects, and the relationship of perceived control to public response. Problems that have limited the usefulness of the empirical base for understanding the psychological mediation of noise effects are reviewed. Research applications of psychological stress theory and noise appraisal models are discussed as essential both to fill in gaps in the literature and to move empirical inquiry in a direction that can inform public policy.


Assuntos
Exposição Ambiental , Ruído/efeitos adversos , Política Pública , Humanos , Estados Unidos
11.
J Biol Chem ; 255(10): 4716-21, 1980 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-6989817

RESUMO

Escherichia coli heat-stable enterotoxin derived from a strain pathogenic for man has been purified 13,000-fold to apparent homogeneity. The purification scheme involved growth in a minimal medium. Amberlite XAD-2 chromatography, acetone fractionation, Sephadex G-25 filtration, DEAE-Sephacel ion exchange chromatography, and Sephadex G-25 gel filtration. This scheme resulted in a white flocculent material which was biologically active in 2.7-ng quantities. Heat-stable enterotoxin was homogeneous as determined by the following: (a) a single peak on gel filtration; (b) a single band on thin layer chromatography; (c) a single band on thin layer electrophoresis; (d) a single NH2-terminal amino acid residue, asparagine; and (e) an amino acid composition demonstrating a stoichiometric relationship among the amino acids. The molecule is composed of 10 different amino acids, a total of 18 amino acid residues, one-third of which are half-cystine. The molecule contains no detectable carbohydrate. Biological activity is promptly lost on treatment with the reducing reagents, 2-mercaptoethanol or dithiothreitol, or after performic acid oxidation, suggesting the presence of disulfide bridges which are required for biological activity.


Assuntos
Enterotoxinas , Escherichia coli/análise , Aminoácidos/análise , Animais , Bioensaio , Carboidratos/análise , Estabilidade de Medicamentos , Enterotoxinas/isolamento & purificação , Escherichia coli/patogenicidade , Temperatura Alta , Humanos , Camundongos , Peso Molecular
12.
J Biol Chem ; 253(16): 5630-4, 1978 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-307552

RESUMO

The complete amino acid sequence of a CNBr-fragment from human alpha1-protease inhibitor has been determined and is shown below. The peptide consists of 109 amino acid residues with 1 oligosaccharide unit. The 2 glutamic acid residues which have previously been shown to be substituted by lysine in the Z and by valine in the S mutant proteins are both located in this CNBr fragment. (formula: see text).


Assuntos
alfa 1-Antitripsina , Sequência de Aminoácidos , Aminoácidos/análise , Brometo de Cianogênio , Humanos , Fragmentos de Peptídeos/análise
15.
Endocrinology ; 98(6): 1430-3, 1976 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1278109

RESUMO

Oxytocin content has been measured by radioimmunoassay in microdissected hypothalamic nuclei. Equal concentrations of oxytocin were found in the supraoptic and the paraventricular nuclei, indicating that both are major sources of the hormone. The concentration of oxytocin in the median eminence was more than three times that in either the supraoptic or the paraventricular nuclei, and significant amounts of oxytocin were also found in the arcuate nucleus and in tow anterior hypothalamic nuclei.


Assuntos
Hipotálamo/análise , Ocitocina/análise , Animais , Hipotálamo Anterior/análise , Masculino , Eminência Mediana/análise , Núcleo Hipotalâmico Paraventricular/análise , Neuro-Hipófise/análise , Ratos , Núcleo Supraóptico/análise
20.
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