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1.
Parasit Vectors ; 14(1): 520, 2021 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-34625096

RESUMEN

BACKGROUND: Sugar feeding is a fundamental behaviour of many mosquito species. For Aedes albopictus, an important vector of dengue virus and chikungunya virus, little is known about its sugar-feeding behaviour, and no studies have been conducted on this in the southern hemisphere. This knowledge is pivotal for determining the potential of attractive targeted sugar baits (ATSBs) to control this important vector. METHODS: The prevalence of sugar was assessed in 1808 Ae. albopictus from Masig Island, Torres Strait, Australia collected between 13 and 25 March 2020. Fructose presence and content in field-collected Ae. albopictus were quantified using the cold anthrone assay. RESULTS: Significantly more male (35.8%) than female (28.4%) Ae. albopictus were sugar fed. There was a significant interaction between sex and time of day on the probability of capturing sugar-fed Ae. albopictus. For both sexes, fructose prevalence and content were higher in mosquitoes caught in the morning than in the afternoon. Female Ae. albopictus collected in the residential habitat were significantly more likely to be sugar fed than those collected in the woodland habitat. CONCLUSIONS: These findings provide baseline information about the sugar-feeding patterns of Ae. albopictus and provide essential information to enable an assessment of the potential of ATSBs for vector suppression and control on Masig Island, with relevance to other locations where this species occurs.


Asunto(s)
Aedes/fisiología , Ecosistema , Conducta Alimentaria , Mosquitos Vectores/fisiología , Azúcares/metabolismo , Aedes/virología , Animales , Australia , Femenino , Masculino , Mosquitos Vectores/virología , Prevalencia , Factores Sexuales , Factores de Tiempo
2.
Int J Drug Policy ; 26(11): 1072-80, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26232055

RESUMEN

BACKGROUND: People who inject drugs (PWID) achieve adherence to and outcomes from hepatitis C virus (HCV) treatment comparable to other patients. Nonetheless, this population has been excluded from treatment by regulation or practice. Approval of safer and more effective oral HCV medicines should offer greater treatment options for PWID, although high medicine prices have led to continued treatment rationing and exclusion in developed countries. In middle-income countries (MICS), treatment is largely unavailable and unaffordable for most PWID. METHODS: Human rights analysis, with its emphasis on the universal and interconnected nature of the economic, social and political spheres, offers a useful framework for HCV treatment reform. Using peer-reviewed and grey literature, as well as community case reports, we discuss barriers to treatment, correlate these barriers to rights violations, and highlight examples of community advocacy to increase treatment for PWID. RESULTS: Structural drivers of lack of treatment access for PWID include stigma in health settings; drug use status as a criterion for treatment exclusion; requirements for fees or registration by name as a drug user prior to treatment initiation; and incarceration/detention in prisons and rehabilitation centers where treatment is unavailable. High medicine prices force further exclusion of PWID, with cost containment masked as concern about treatment adherence. These barriers correlate to multiple rights violations, including of the rights to privacy; non-discrimination; health; freedom of information; fair trial; and freedom from cruel, inhuman and degrading treatment. CONCLUSIONS: Needed reforms include decriminalization of drug use, possession of drugs and drug injecting equipment; removal of exclusionary or discriminatory treatment protocols; approaches to strengthen links between health providers and increase participation of PWID in treatment design and implementation; and measures to increase transparency in government/pharmaceutical company negotiations and reduce treatment price.


Asunto(s)
Hepatitis C/terapia , Derechos Humanos , Abuso de Sustancias por Vía Intravenosa/complicaciones , Abuso de Sustancias por Vía Intravenosa/rehabilitación , Antivirales/economía , Antivirales/uso terapéutico , Países en Desarrollo , Costos de los Medicamentos , Accesibilidad a los Servicios de Salud , Hepatitis C/economía , Humanos , Estigma Social , Abuso de Sustancias por Vía Intravenosa/economía
3.
Clin Pharmacol Ther ; 96(2): 162-5, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24853733

RESUMEN

Over the past decade, landmark collaboration between regulatory agencies, pharmaceutical companies, academia, and patient community representatives has enabled the development and approval of new hepatitis C virus (HCV) treatment regimens with unprecedented speed. By providing a neutral platform for cross-sector engagement, the Forum for Collaborative HIV Research's(1) HCV Drug Development Advisory Group played a critical role in fostering this collaboration and expediting drug development. The applicability of this model to other therapeutic areas should be explored.


Asunto(s)
Comités Consultivos/tendencias , Antivirales/administración & dosificación , Conducta Cooperativa , Descubrimiento de Drogas/tendencias , Hepatitis C/tratamiento farmacológico , Comités Consultivos/legislación & jurisprudencia , Animales , Descubrimiento de Drogas/legislación & jurisprudencia , Hepacivirus/efectos de los fármacos , Hepacivirus/fisiología , Hepatitis C/epidemiología , Humanos
5.
Phys Rev Lett ; 109(17): 172501, 2012 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-23215181

RESUMEN

Recent calculations suggest that the rate of neutron capture by (130)Sn has a significant impact on late-time nucleosynthesis in the r process. Direct capture into low-lying bound states is expected to be significant in neutron capture near the N=82 closed shell, so r-process reaction rates may be strongly impacted by the properties of neutron single particle states in this region. In order to investigate these properties, the (d,p) reaction has been studied in inverse kinematics using a 630 MeV beam of (130)Sn (4.8 MeV/u) and a (CD(2))(n) target. An array of Si strip detectors, including the Silicon Detector Array and an early implementation of the Oak Ridge Rutgers University Barrel Array, was used to detect reaction products. Results for the (130)Sn(d, p)(131)Sn reaction are found to be very similar to those from the previously reported (132)Sn(d, p)(133)Sn reaction. Direct-semidirect (n,γ) cross section calculations, based for the first time on experimental data, are presented. The uncertainties in these cross sections are thus reduced by orders of magnitude from previous estimates.

6.
HIV Clin Trials ; 13(2): 90-102, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22510356

RESUMEN

BACKGROUND: The influence of chronic hepatitis C virus (HCV) infection on the risk, timing, and type of AIDS-defining illnesses (ADIs) is not well described. To this end, rates of ADIs were evaluated in a Canadian cohort of HIV seropositive individuals receiving highly active antiretroviral therapy (HAART). METHODS: ADIs were classified into 6 Centers for Disease Control and Prevention (CDC)-defined etiological subgroups: non-Hodgkin lymphoma, viral infection, bacterial infection, HIV-related disease, protozoal infection, and mycotic infection. Generalized estimating equation (GEE) Poisson regression models were used to estimate the effect of HCV on rates of ADIs after adjusting for covariates. RESULTS: Among 2,706 HAART recipients, 768 (28%) were HCV coinfected. Rates of all ADIs combined and of bacterial infection, HIV-related disease, and mycotic infection were increased in HCV-coinfected persons and among those with CD4 counts <200 cells/mm3 HCV was associated with an increased risk of ADIs (rate ratio [RR], 1.38; 95% CI, 1.01-1.88) and a 2-fold increased risk of mycotic infections (RR, 2.21; 95% CI, 1.35-3.62) in univariate analyses and after adjusting for age, baseline viral load, baseline CD4 count, and region of Canada. However, after further adjustment for HAART interruptions, HCV was no longer associated with an increased rate of ADIs overall (RR, 1.13; 95% CI, 0.80-1.59), but remained associated with an increased rate of mycotic infections (RR, 1.97, 95% CI, 1.08-3.61). CONCLUSION: Although HCV coin-fected individuals are at increased risk of developing ADIs overall, our analysis suggests that behavioral variables associated with HCV (including rates of retention on HAART), and not biological interactions with HCV itself, are primarily responsible.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Terapia Antirretroviral Altamente Activa , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Hepatitis C Crónica/complicaciones , Adulto , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/uso terapéutico , Canadá/epidemiología , Estudios de Cohortes , Coinfección , Femenino , Infecciones por VIH/epidemiología , Hepatitis C Crónica/epidemiología , Humanos , Masculino , Persona de Mediana Edad
7.
Nature ; 465(7297): 454-7, 2010 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-20505723

RESUMEN

Atomic nuclei have a shell structure in which nuclei with 'magic numbers' of neutrons and protons are analogous to the noble gases in atomic physics. Only ten nuclei with the standard magic numbers of both neutrons and protons have so far been observed. The nuclear shell model is founded on the precept that neutrons and protons can move as independent particles in orbitals with discrete quantum numbers, subject to a mean field generated by all the other nucleons. Knowledge of the properties of single-particle states outside nuclear shell closures in exotic nuclei is important for a fundamental understanding of nuclear structure and nucleosynthesis (for example the r-process, which is responsible for the production of about half of the heavy elements). However, as a result of their short lifetimes, there is a paucity of knowledge about the nature of single-particle states outside exotic doubly magic nuclei. Here we measure the single-particle character of the levels in (133)Sn that lie outside the double shell closure present at the short-lived nucleus (132)Sn. We use an inverse kinematics technique that involves the transfer of a single nucleon to the nucleus. The purity of the measured single-particle states clearly illustrates the magic nature of (132)Sn.

8.
Phys Rev Lett ; 105(17): 172501, 2010 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-21231037

RESUMEN

A study of cooled ¹97Au projectile-fragmentation products has been performed with a storage ring. This has enabled metastable nuclear excitations with energies up to 3 MeV, and half-lives extending to minutes or longer, to be identified in the neutron-rich nuclides ¹8³(,)¹84(,)¹86Hf and ¹86(,)¹87Ta. The results support the prediction of a strongly favored isomer region near neutron number 116.

9.
Aliment Pharmacol Ther ; 30(1): 14-27, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19416131

RESUMEN

BACKGROUND: Treatment of hepatitis C virus (HCV) infection with pegylated interferon/ribavirin achieves sustained virological response in up to 56% of HCV mono-infected patients and 40% of HCV/human immunodeficiency virus (HIV)-co-infected patients. The relationship of patient adherence to outcome warrants study. AIM: To review comprehensively research on patient-missed doses to HCV treatment and discuss applicable research from adherence to HIV antiretroviral therapy. METHODS: Publications were identified by PubMed searches using the keywords: adherence, compliance, hepatitis C virus, interferon and ribavirin. RESULTS: The term 'non-adherence' differs in how it is used in the HCV from the HIV literature. In HCV, 'non-adherence' refers primarily to dose reductions by the clinician and early treatment discontinuation. In contrast, in HIV, 'non-adherence' refers primarily to patient-missed doses. Few data have been published on the rates of missed dose adherence to pegylated interferon/ribavirin and its relationship to virological response. CONCLUSIONS: As HCV treatment becomes more complex with new classes of agents, adherence will be increasingly important to treatment success as resistance mutations may develop with suboptimal dosing of HCV enzyme inhibitors. HIV adherence research can be applied to that on HCV to establish accurate methods to assess adherence, investigate determinants of non-adherence and develop strategies to optimize adherence.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Interferones/uso terapéutico , Cumplimiento de la Medicación/estadística & datos numéricos , Ribavirina/uso terapéutico , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Humanos
10.
Neuroscience ; 148(3): 644-52, 2007 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-17706879

RESUMEN

Soy phytoestrogens have been proposed as an alternative to estrogen replacement therapy and have demonstrated potential neuroprotective effects in the brain. We have shown that a high soy diet significantly reduces infarct size following permanent middle cerebral artery occlusion (MCAO). Here, we tested the hypothesis that a high soy diet would attenuate programmed cell death after stroke. Adult female Sprague-Dawley rats were ovariectomized and fed either an isoflavone-reduced diet (IFP) or a high soy diet (SP) for 2 weeks before undergoing 90 min of transient middle cerebral artery occlusion (tMCAO) followed by 22.5 h reperfusion. Infarct size, as assessed by triphenyltetrazolium chloride staining, was significantly reduced by a high soy diet (P<0.05). Apoptosis in the ischemic cortex, measured by TUNEL staining, was significantly reduced by the high soy diet. The number of active caspase-3 positive cells and caspase-mediated alpha-spectrin cleavage were also significantly decreased in the ischemic cortex of SP rats. Furthermore, nuclear translocation of apoptosis-inducing factor (AIF) was significantly reduced in the ischemic cortex of SP rats. Soy significantly increased bcl-x(L) mRNA and protein expression in the ischemic cortex compared with IFP rats. Immunohistochemistry revealed increased neuronal expression of bcl-2 and bcl-x(L) in the ischemic cortex of both IFP and SP rats following tMCAO. These results suggest that a high soy diet decreases both caspase-dependent and caspase-independent programmed cell death following tMCAO. Further, a high soy diet enhances expression of the cell survival factor bcl-x(L) following tMCAO, contributing to the neuroprotective effects of soy in the ischemic cortex.


Asunto(s)
Apoptosis/efectos de los fármacos , Degeneración Nerviosa/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Fitoestrógenos/farmacología , Accidente Cerebrovascular/tratamiento farmacológico , Proteína bcl-X/efectos de los fármacos , Transporte Activo de Núcleo Celular/efectos de los fármacos , Transporte Activo de Núcleo Celular/genética , Animales , Apoptosis/genética , Factor Inductor de la Apoptosis/efectos de los fármacos , Factor Inductor de la Apoptosis/genética , Factor Inductor de la Apoptosis/metabolismo , Proteínas Reguladoras de la Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatología , Caspasas/efectos de los fármacos , Caspasas/genética , Caspasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Modelos Animales de Enfermedad , Estrógenos/metabolismo , Femenino , Alimentos Formulados , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/genética , Infarto de la Arteria Cerebral Media/metabolismo , Degeneración Nerviosa/genética , Degeneración Nerviosa/metabolismo , Fármacos Neuroprotectores/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Fitoestrógenos/metabolismo , Fitoestrógenos/uso terapéutico , Proteínas Proto-Oncogénicas c-bcl-2/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Alimentos de Soja , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
11.
Arch Biochem Biophys ; 391(2): 235-44, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11437355

RESUMEN

o-Phthalaldehyde (OPA) is a bifunctional reagent that forms an isoindole derivative by reacting with cysteine and lysine residues separated by approximately 0.3 nm. OPA inhibits sarcoplasmic reticulum (SR) Ca(2+)-ATPase activity at low micromolar concentrations and induces Ca(2+) release from actively loaded SR vesicles by activating the ryanodine receptor from fast twitch skeletal muscle. Both ryanodine binding and single-channel activity show a biphasic concentration dependence. At low OPA concentrations (<100 microM), ryanodine binding and single channel activity are stimulated, while at higher concentrations, a time-dependent sequential activation and inhibition of receptor binding is observed. Activation is characterized by a Ca(2+)-independent increase in maximal receptor occupancy. Data are presented to support a model in which Ca(2+) channel and ryanodine binding activity are enhanced due to an intramolecular cross-linking of nearby lysine and nonhyperreactive cysteine residues. OPA complexation with endogenous lysine residue(s) is critical for receptor activation.


Asunto(s)
ATPasa de Ca(2+) y Mg(2+)/antagonistas & inhibidores , Calcio/metabolismo , Retículo Sarcoplasmático/efectos de los fármacos , o-Ftalaldehído/farmacología , Animales , ATPasa de Ca(2+) y Mg(2+)/metabolismo , Relación Dosis-Respuesta a Droga , Músculo Esquelético/citología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Conejos , Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo , Tritio
15.
Int J STD AIDS ; 11(2): 105-11, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10678478

RESUMEN

A community intervention trial was undertaken in KwaZulu Natal, South Africa to evaluate the effectiveness of a high school drama-in-education programme. Seven pairs of secondary schools were randomized to receive either written information about HIV/AIDS or the drama programme. Questionnaire surveys of knowledge, attitude and behaviour were compared before and 6 months after the interventions. One thousand and eighty students participated in the first survey and 699 in the second. Improvements in knowledge (P=0.0002) and attitudes (P < 0.00001) about HIV/AIDS were demonstrated in pupils at schools receiving the drama programme when compared to pupils receiving written information alone. These changes were independent of age, gender, school or previous sexual experience. In schools receiving the drama programme, sexually active pupils reported an increase in condom use (P < 0.01). It is important to provide resources to sustain such programmes and to obtain stronger evidence of effect on behaviour by measuring changes in HIV incidence.


PIP: South African research indicates that adolescents' risk of becoming infected with HIV is increased by a lifestyle involving a greater degree of exploration, experimentation, and rebellion. The high prevalence of sexually transmitted diseases and the high rate of adolescent pregnancy confirm the existence of a pattern of early onset of sexual intercourse, multiple partners and a low incidence of condom use. Prevention programs such as the Drama Approach to AIDS (DramAide) has been initiated in Africa to reduce HIV transmission. This paper evaluates the effectiveness of the DramAide, a high school drama-in-education program conducted in KwaZulu Natal, South Africa. Using a randomized community intervention trial, seven pairs of secondary schools were randomized to receive either written information about HIV/AIDS or the drama program. Questionnaire surveys of knowledge, attitude and behavior were compared before and 6 months after the interventions. A total of 1080 students participated in the first survey, while there were 699 student participants in the second. Improvements in knowledge (P = 0.0002) and attitudes (P 0.00001) about HIV/AIDS were noted in the drama program receivers as compared with the written information receivers. Increase in condom use by sexually active students was also reported for drama program receivers (P 0.01). Thus, it is important to provide resources to drama-in-education programs and obtain stronger evidence of effect on behavior by measuring changes in HIV incidence.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/prevención & control , Educación en Salud , Adolescente , Actitud , Femenino , Humanos , Masculino , Conducta Sexual , Sudáfrica , Estudiantes
16.
Can J Microbiol ; 45(6): 472-9, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10453475

RESUMEN

The response of a yeast unsaturated fatty acid auxotroph, defective in delta 9-desaturase activity, to heat and ethanol stresses was examined. The most heat- and ethanol-tolerant cells had membranes enriched with oleic acid (C18:1), followed in order by cells enriched with linoleic (C18:2) and linolenic (C18:3) acids. Cells subjected to a heat shock (25-37 degrees C for 30 min) accumulated trehalose and synthesized typical heat shock proteins. Although there were no obvious differences in protein profiles attributable to lipid supplementation of the mutant, relative protein synthesis as determined by densitometric analysis of autoradiograms suggested that hsp expression was different. However, there was no consistent relationship between the synthesis of heat shock proteins and the acquisition of thermotolerance in the lipid supplemented auxotroph or related wild type. Furthermore, trehalose accumulation was also not closely related to stress tolerance. On the other hand, the data presented indicated a more consistent role for membrane lipid composition in stress tolerance than trehalose, heat shock proteins, or ergosterol. We suggest that the sensitivity of C18:3-enriched cells to heat and ethanol may be attributable to membrane damage associated with increases in membrane fluidity and oxygen-derived free radical attack of membrane lipids.


Asunto(s)
Etanol/farmacología , Proteínas de Choque Térmico/metabolismo , Calor , Lípidos de la Membrana/química , Saccharomyces cerevisiae/fisiología , Electroforesis en Gel de Poliacrilamida , Ergosterol/análisis , Ácidos Grasos/análisis , Lípidos de la Membrana/fisiología , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Trehalosa/análisis
18.
FEMS Microbiol Lett ; 169(1): 191-7, 1998 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-9851052

RESUMEN

The role of ergosterol in yeast stress tolerance, together with heat shock proteins (hsps) and trehalose, was examined in a sterol auxotrophic mutant of Saccharomyces cerevisiae. Ergosterol levels paralleled viability data, with cells containing higher levels of the sterol exhibiting greater tolerances to heat and ethanol. Although the mutant synthesised hsps and accumulated trehalose upon heat shock to the same levels as the wild-type cells, these parameters did not relate to stress tolerance. These results indicate that the role of ergosterol in stress tolerance is independent of hsps or trehalose.


Asunto(s)
Ergosterol/metabolismo , Respuesta al Choque Térmico , Saccharomyces cerevisiae/fisiología , Ergosterol/análisis , Ácidos Grasos/análisis , Proteínas Fúngicas/biosíntesis , Proteínas de Choque Térmico/metabolismo , Membranas/química , Trehalosa/metabolismo
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