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1.
Lancet ; 402(10417): 2101-2110, 2023 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-37979594

RESUMEN

BACKGROUND: In areas co-endemic for Plasmodium vivax and Plasmodium falciparum there is an increased risk of P vivax parasitaemia following P falciparum malaria. Radical cure is currently only recommended for patients presenting with P vivax malaria. Expanding the indication for radical cure to patients presenting with P falciparum malaria could reduce their risk of subsequent P vivax parasitaemia. METHODS: We did a multicentre, open-label, superiority randomised controlled trial in five health clinics in Bangladesh, Indonesia, and Ethiopia. In Bangladesh and Indonesia, patients were excluded if they were younger than 1 year, whereas in Ethiopia patients were excluded if they were younger than 18 years. Patients with uncomplicated P falciparum monoinfection who had fever or a history of fever in the 48 h preceding clinic visit were eligible for enrolment and were required to have a glucose-6-dehydrogenase (G6PD) activity of 70% or greater. Patients received blood schizontocidal treatment (artemether-lumefantrine in Ethiopia and Bangladesh and dihydroartemisinin-piperaquine in Indonesia) and were randomly assigned (1:1) to receive either high-dose short-course oral primaquine (intervention arm; total dose 7 mg/kg over 7 days) or standard care (standard care arm; single dose oral primaquine of 0·25 mg/kg). Random assignment was done by an independent statistician in blocks of eight by use of sealed envelopes. All randomly assigned and eligible patients were included in the primary and safety analyses. The per-protocol analysis excluded those who did not complete treatment or had substantial protocol violations. The primary endpoint was the incidence risk of P vivax parasitaemia on day 63. This trial is registered at ClinicalTrials.gov, NCT03916003. FINDINGS: Between Aug 18, 2019, and March 14, 2022, a total of 500 patients were enrolled and randomly assigned, and 495 eligible patients were included in the intention-to-treat analysis (246 intervention and 249 control). The incidence risk of P vivax parasitaemia at day 63 was 11·0% (95% CI 7·5-15·9) in the standard care arm compared with 2·5% (1·0-5·9) in the intervention arm (hazard ratio 0·20, 95% CI 0·08-0·51; p=0·0009). The effect size differed with blood schizontocidal treatment and site. Routine symptom reporting on day 2 and day 7 were similar between groups. In the first 42 days, there were a total of four primaquine-related adverse events reported in the standard care arm and 26 in the intervention arm; 132 (92%) of all 143 adverse events were mild. There were two serious adverse events in the intervention arm, which were considered unrelated to the study drug. None of the patients developed severe anaemia (defined as haemoglobin <5 g/dL). INTERPRETATION: In patients with a G6PD activity of 70% or greater, high-dose short-course primaquine was safe and relatively well tolerated and reduced the risk of subsequent P vivax parasitaemia within 63 days by five fold. Universal radical cure therefore potentially offers substantial clinical, public health, and operational benefits, but these benefits will vary with endemic setting. FUNDING: Australian Academy of Science Regional Collaborations Program, Bill & Melinda Gates Foundation, and National Health and Medical Research Council.


Asunto(s)
Antimaláricos , Malaria Falciparum , Malaria Vivax , Malaria , Humanos , Primaquina/efectos adversos , Antimaláricos/efectos adversos , Plasmodium vivax , Arteméter/farmacología , Arteméter/uso terapéutico , Combinación Arteméter y Lumefantrina/uso terapéutico , Australia , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Malaria Vivax/tratamiento farmacológico , Malaria Vivax/epidemiología , Malaria/tratamiento farmacológico , Plasmodium falciparum , Parasitemia/tratamiento farmacológico , Parasitemia/epidemiología
2.
Phys Rev Lett ; 131(4): 041403, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37566847

RESUMEN

In this Letter, we present the design and performance of the frequency-dependent squeezed vacuum source that will be used for the broadband quantum noise reduction of the Advanced Virgo Plus gravitational-wave detector in the upcoming observation run. The frequency-dependent squeezed field is generated by a phase rotation of a frequency-independent squeezed state through a 285 m long, high-finesse, near-detuned optical resonator. With about 8.5 dB of generated squeezing, up to 5.6 dB of quantum noise suppression has been measured at high frequency while close to the filter cavity resonance frequency, the intracavity losses limit this value to about 2 dB. Frequency-dependent squeezing is produced with a rotation frequency stability of about 6 Hz rms, which is maintained over the long term. The achieved results fulfill the frequency dependent squeezed vacuum source requirements for Advanced Virgo Plus. With the current squeezing source, considering also the estimated squeezing degradation induced by the interferometer, we expect a reduction of the quantum shot noise and radiation pressure noise of up to 4.5 dB and 2 dB, respectively.

3.
Malar J ; 22(1): 306, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37817240

RESUMEN

BACKGROUND: Imperfect adherence is a major barrier to effective primaquine radical cure of Plasmodium vivax. This study investigated the effect of reduced adherence on the risk of P. vivax recurrence. METHODS: Efficacy studies of patients with uncomplicated P. vivax malaria, including a treatment arm with daily primaquine, published between January 1999 and March 2020 were identified. Individual patient data from eligible studies were pooled using standardized methodology. Adherence to primaquine was inferred from i) the percentage of supervised doses and ii) the total mg/kg dose received compared to the target total mg/kg dose per protocol. The effect of adherence to primaquine on the incidence of P. vivax recurrence between days 7 and 90 was investigated by Cox regression analysis. RESULTS: Of 82 eligible studies, 32 were available including 6917 patients from 18 countries. For adherence assessed by percentage of supervised primaquine, 2790 patients (40.3%) had poor adherence (≤ 50%) and 4127 (59.7%) had complete adherence. The risk of recurrence by day 90 was 14.0% [95% confidence interval: 12.1-16.1] in patients with poor adherence compared to 5.8% [5.0-6.7] following full adherence; p = 0.014. After controlling for age, sex, baseline parasitaemia, and total primaquine dose per protocol, the rate of the first recurrence was higher following poor adherence compared to patients with full adherence (adjusted hazard ratio (AHR) = 2.3 [1.8-2.9]). When adherence was quantified by total mg/kg dose received among 3706 patients, 347 (9.4%) had poor adherence, 88 (2.4%) had moderate adherence, and 3271 (88.2%) had complete adherence to treatment. The risks of recurrence by day 90 were 8.2% [4.3-15.2] in patients with poor adherence and 4.9% [4.1-5.8] in patients with full adherence; p < 0.001. CONCLUSION: Reduced adherence, including less supervision, increases the risk of vivax recurrence.


Asunto(s)
Antimaláricos , Antagonistas del Ácido Fólico , Malaria Vivax , Humanos , Primaquina/efectos adversos , Antimaláricos/farmacología , Plasmodium vivax , Recurrencia , Malaria Vivax/tratamiento farmacológico , Malaria Vivax/prevención & control , Malaria Vivax/complicaciones , Antagonistas del Ácido Fólico/farmacología
4.
BMC Med Res Methodol ; 23(1): 198, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37667204

RESUMEN

INTRODUCTION: Symptoms reported following the administration of investigational drugs play an important role in decisions for registration and treatment guidelines. However, symptoms are subjective, and interview methods to quantify them are difficult to standardise. We explored differences in symptom reporting across study sites of a multicentre antimalarial trial, with the aim of informing trial design and the interpretation of safety and tolerability data. METHODS: Data were derived from the IMPROV trial, a randomised, placebo-controlled double blinded trial of high dose primaquine to prevent Plasmodium vivax recurrence conducted in eight study sites in Afghanistan, Ethiopia, Indonesia and Vietnam. At each follow up visit a 13-point symptom questionnaire was completed. The number and percentage of patients with clinically relevant symptoms following the administration of primaquine or placebo, were reported by study site including vomiting, diarrhoea, anorexia, nausea, abdominal pain and dizziness. Multivariable logistic regression was used to estimate the confounder-adjusted site-specific proportion of each symptom. RESULTS: A total of 2,336 patients were included. The greatest variation between sites in the proportion of patients reporting symptoms was for anorexia between day 0 and day 13: 97.3% (361/371) of patients in Arba Minch, Ethiopia, reported the symptom compared with 4.7% (5/106) of patients in Krong Pa, Vietnam. Differences attenuated slightly after adjusting for treatment arm, age, sex, day 0 parasite density and fever; with the adjusted proportion for anorexia ranging from 4.8% to 97.0%. Differences between sites were greater for symptoms graded as mild or moderate compared to those rated as severe. Differences in symptom reporting were greater between study sites than between treatment arms within the same study site. CONCLUSION: Despite standardised training, there was large variation in symptom reporting across trial sites. The reporting of severe symptoms was less skewed compared to mild and moderate symptoms, which are likely to be more subjective. Trialists should clearly distinguish between safety and tolerability outcomes. Differences between trial arms were much less variable across sites, suggesting that the relative difference in reported symptoms between intervention and control group is more relevant than absolute numbers and should be reported when possible. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01814683; March 20th, 2013.


Asunto(s)
Antimaláricos , Humanos , Antimaláricos/efectos adversos , Primaquina , Anorexia , Afganistán , Grupos Control
5.
Malar J ; 21(1): 327, 2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36372877

RESUMEN

Kalimantan is a part of Indonesia, which occupies the southern three-quarters of the island of Borneo, sharing a border with the Malaysian states of Sabah and Sarawak. Although most areas of Kalimantan have low and stable transmission of Plasmodium falciparum and Plasmodium vivax, there are relatively high case numbers in the province of East Kalimantan. Two aspects of malaria endemicity in Kalimantan differentiate it from the rest of Indonesia, namely recent deforestation and potential exposure to the zoonotic malaria caused by Plasmodium knowlesi that occurs in relatively large numbers in adjacent Malaysian Borneo. In the present review, the history of malaria and its current epidemiology in Kalimantan are examined, including control and eradication efforts over the past two centuries, mosquito vector prevalence, anti-malarial use and parasite resistance, and the available data from case reports of knowlesi malaria and the presence of conditions which would support transmission of this zoonotic infection.


Asunto(s)
Antimaláricos , Malaria , Plasmodium knowlesi , Animales , Humanos , Indonesia/epidemiología , Malaria/epidemiología , Malaria/prevención & control , Malaria/tratamiento farmacológico , Antimaláricos/uso terapéutico , Plasmodium falciparum , Malasia/epidemiología
6.
Malar J ; 21(1): 280, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36184593

RESUMEN

BACKGROUND: Plasmodial species naturally infecting orang-utans, Plasmodium pitheci and Plasmodium silvaticum, have been rarely described and reportedly cause relatively benign infections. Orang-utans at Rescue Rehabilitation Centres (RRC) across the orang-utan natural range suffer from malaria illness. However, the species involved and clinical pathology of this illness have not been described in a systematic manner. The objective of the present study was to identify the Plasmodium species infecting orang-utans under our care, define the frequency and character of malaria illness among the infected, and establish criteria for successful diagnosis and treatment. METHODS: During the period 2017-2021, prospective active surveillance of malaria among 131 orang-utans resident in a forested RRC in West Kalimantan (Indonesia) was conducted. A total of 1783 blood samples were analysed by microscopy and 219 by nucleic acid based (PCR) diagnostic testing. Medical records of inpatient orang-utans at the centre from 2010 to 2016 were also retrospectively analysed for instances of symptomatic malaria. RESULTS: Active surveillance revealed 89 of 131 orang-utans were positive for malaria at least once between 2017 and 2021 (period prevalence = 68%). During that period, 14 cases (affecting 13 orang-utans) developed clinical malaria (0.027 attacks/orang-utan-year). Three other cases were found to have occurred from 2010-2016. Sick individuals presented predominantly with fever, anaemia, thrombocytopenia, and leukopenia. All had parasitaemias in excess of 4000/µL and as high as 105,000/µL, with severity of illness correlating with parasitaemia. Illness and parasitaemia quickly resolved following administration of artemisinin-combined therapies. High levels of parasitaemia also sometimes occurred in asymptomatic cases, in which case, parasitaemia cleared spontaneously. CONCLUSIONS: This study demonstrated that P. pitheci very often infected orang-utans at this RRC. In about 14% of infected orang-utans, malaria illness occurred and ranged from moderate to severe in nature. The successful clinical management of acute pitheci malaria is described. Concerns are raised about this infection potentially posing a threat to this endangered species in the wild.


Asunto(s)
Artemisininas , Malaria , Ácidos Nucleicos , Plasmodium , Animales , Humanos , Indonesia/epidemiología , Malaria/epidemiología , Pongo pygmaeus , Estudios Prospectivos , Centros de Rehabilitación , Estudios Retrospectivos
7.
Br J Clin Pharmacol ; 88(6): 2657-2664, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34997616

RESUMEN

Methaemoglobin results from the oxidation of ferrous to ferric iron in the centre of the haem moiety of haemoglobin. The production of dose-dependent methaemoglobinaemia by 8-aminoquinoline antimalarial drugs appears to be associated with, but is not directly linked to, therapeutic efficacy against latent Plasmodium vivax and Plasmodium ovale malarias (radical cure). Iatrogenic methaemoglobinaemia may be a useful pharmacodynamic measure in 8-aminoquinoline drug and dose optimization.


Asunto(s)
Antimaláricos , Metahemoglobinemia , Aminoquinolinas/efectos adversos , Antimaláricos/uso terapéutico , Humanos , Metahemoglobinemia/inducido químicamente , Metahemoglobinemia/tratamiento farmacológico , Plasmodium vivax
8.
Public Health Nutr ; : 1-28, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36472075

RESUMEN

OBJECTIVE: To examine energy drink consumption among adolescents in the United Kingdom (UK) and associations with deprivation and dietary inequalities. DESIGN: Quantitative dietary and demographic data from the National Diet and Nutrition Survey (NDNS) repeated cross-sectional survey were analysed using logistic regression models. Qualitative data from semi-structured interviews were analysed using inductive thematic analysis. SETTING: UK. PARTICIPANTS: Quantitative data: nationally representative sample of 2587 adolescents aged 11-18 years. Qualitative data: 20 parents, 9 teachers, and 28 adolescents from Hampshire, UK. RESULTS: NDNS data showed adolescents' consumption of energy drinks was associated with poorer dietary quality (OR 0.46 per SD; 95% CI 0.37, 0.58; p<0.001). Adolescents from more deprived areas and lower income households were more likely to consume energy drinks than those in more affluent areas and households (OR 1.40; 95%CI 1.16, 1.69; p<0.001; OR 0.98 per £1000; 95%CI, 0.96, 0.99; p<0.001 respectively). Between 2008 and 2016, energy drink consumption among adolescents living in the most deprived areas increased, but decreased among those living in the most affluent neighbourhoods (p=0.04). Qualitative data identified three themes. First, many adolescents drink energy drinks because of their friends and because the unbranded drinks are cheap. Second, energy drink consumption clusters with other unhealthy eating behaviours and adolescents don't know why energy drinks are unhealthy. Third, adolescents believe voluntary bans in retail outlets and schools do not work. CONCLUSIONS: This study supports the introduction of age-dependent legal restrictions on the sale of energy drinks which may help curb existing socio-economic disparities in adolescents' energy drink intake.

9.
PLoS Med ; 18(10): e1003799, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34618814

RESUMEN

J. Kevin Baird and colleagues, examine and discuss the estimated global burden of vivax malaria and it's biological, clinical, and public health complexity.


Asunto(s)
Costo de Enfermedad , Internacionalidad , Malaria Vivax/epidemiología , Plasmodium vivax/fisiología , Animales , Geografía , Humanos , Incidencia , Malaria Vivax/genética , Malaria Vivax/parasitología , Parásitos/fisiología , Salud Pública , Factores de Riesgo , Incertidumbre
10.
BMC Med ; 19(1): 146, 2021 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-34144715

RESUMEN

BACKGROUND: As in many countries, quantifying COVID-19 spread in Indonesia remains challenging due to testing limitations. In Java, non-pharmaceutical interventions (NPIs) were implemented throughout 2020. However, as a vaccination campaign launches, cases and deaths are rising across the island. METHODS: We used modelling to explore the extent to which data on burials in Jakarta using strict COVID-19 protocols (C19P) provide additional insight into the transmissibility of the disease, epidemic trajectory, and the impact of NPIs. We assess how implementation of NPIs in early 2021 will shape the epidemic during the period of likely vaccine rollout. RESULTS: C19P burial data in Jakarta suggest a death toll approximately 3.3 times higher than reported. Transmission estimates using these data suggest earlier, larger, and more sustained impact of NPIs. Measures to reduce sub-national spread, particularly during Ramadan, substantially mitigated spread to more vulnerable rural areas. Given current trajectory, daily cases and deaths are likely to increase in most regions as the vaccine is rolled out. Transmission may peak in early 2021 in Jakarta if current levels of control are maintained. However, relaxation of control measures is likely to lead to a subsequent resurgence in the absence of an effective vaccination campaign. CONCLUSIONS: Syndromic measures of mortality provide a more complete picture of COVID-19 severity upon which to base decision-making. The high potential impact of the vaccine in Java is attributable to reductions in transmission to date and dependent on these being maintained. Increases in control in the relatively short-term will likely yield large, synergistic increases in vaccine impact.


Asunto(s)
Vacunas contra la COVID-19/administración & dosificación , COVID-19/mortalidad , COVID-19/epidemiología , COVID-19/terapia , Humanos , Programas de Inmunización/métodos , Indonesia , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , Síndrome , Vacunación/métodos , Vacunación/estadística & datos numéricos
11.
Phys Rev Lett ; 126(13): 131103, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33861094

RESUMEN

We report on the first subpicometer interferometer flown in space. It was part of ESA's Laser Interferometer Space Antenna (LISA) Pathfinder mission and performed the fundamental measurement of the positional and angular motion of two free-falling test masses. The interferometer worked immediately, stably, and reliably from switch on until the end of the mission with exceptionally low residual noise of 32.0_{-1.7}^{+2.4} fm/sqrt[Hz], significantly better than required. We present an upper limit for the sensor performance at millihertz frequencies and a model for the measured sensitivity above 200 mHz.

12.
Malar J ; 20(1): 177, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33836772

RESUMEN

BACKGROUND: A goal of malaria epidemiological interventions is the detection and treatment of parasite reservoirs in endemic areas-an activity that is expected to reduce local transmission. Since the gametocyte is the only transmissible stage from human host to mosquito vector, this study evaluated the pre and post presence of gametocytes during a mass screening and treatment (MST) intervention conducted during 2013 in East Nusa Tenggara, Indonesia. METHODS: RT-qPCR targeting pfs25 and pvs25 transcripts-gametocyte molecular markers for Plasmodium falciparum and Plasmodium vivax, respectively, was performed to detect and quantify gametocytes in blood samples of P. falciparum and P. vivax-infected subjects over the course of the MST study. The presence of both asexual and sexual parasites in microscopic and submicroscopic infections was compared from the start and end of the MST, using proportion tests as well as parametric and non-parametric tests. RESULTS: Parasite prevalence remained unchanged for P. falciparum (6% = 52/811 versus 7% = 50/740, p = 0.838), and decreased slightly for P. vivax (24% = 192/811 versus 19% = 142/740, p = 0.035) between the MST baseline and endpoint. No significant difference was observed in gametocyte prevalence for either P. falciparum (2% = 19/803 versus 3% = 23/729, p = 0.353, OR = 1.34, 95%CI = 0.69-2.63), or P. vivax (7% = 49/744 versus 5% = 39/704, p = 0.442, OR = 0.83, 95%CI = 0.52-1.31). Even though there was an insignificant difference between the two time points, the majority of parasite positive subjects at the endpoint had been negative at baseline (P. falciparum: 66% = 29/44, P. vivax: 60% = 80/134). This was similarly demonstrated for the transmissible stage-where the majority of gametocyte positive subjects at the endpoint were negative at baseline (P. falciparum: 95% = 20/21, P. vivax: 94% = 30/32). These results were independent of treatment provided during MST activities. No difference was demonstrated in parasite and gametocyte density between both time points either in P. falciparum or P. vivax. CONCLUSION: In this study area, similar prevalence rates of P. falciparum and P. vivax parasites and gametocytes before and after MST, although in different individuals, points to a negligible impact on the parasite reservoir. Treatment administration based on parasite positivity as implemented in the MST should be reevaluated for the elimination strategy in the community. Trial registration Clinical trials registration NCT01878357. Registered 14 June 2013, https://www.clinicaltrials.gov/ct2/show/NCT01878357.


Asunto(s)
Portador Sano/epidemiología , Malaria Falciparum/diagnóstico , Malaria Vivax/diagnóstico , Tamizaje Masivo , Plasmodium falciparum/aislamiento & purificación , Plasmodium vivax/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Portador Sano/parasitología , Niño , Preescolar , Femenino , Humanos , Indonesia/epidemiología , Lactante , Estudios Longitudinales , Malaria Falciparum/epidemiología , Malaria Falciparum/prevención & control , Malaria Vivax/epidemiología , Malaria Vivax/prevención & control , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Adulto Joven
13.
Public Health ; 190: 152-159, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33419526

RESUMEN

OBJECTIVE: The objective of the study is to identify the barriers to UK Black, Asian and Minority Ethnic (BAME) women attending breast screening and subsequently, support the growing evidence base providing solutions to the public health problem of ethnic variation within screening attendance. STUDY DESIGN: A systematic review and thematic analysis of UK-based, qualitative studies concerning BAME women. METHODS: The methodology of this review is based on Cochrane guidelines. A search strategy was applied to Embase, PubMed and Medline. Predefined inclusion and exclusion criteria yielded 8 final articles which were appraised and thematically analysed. RESULTS: The main findings of the review revealed three overarching themes: knowledge-related, access-related and cultural-related factors. The emphasis of the importance of knowledge was highlighted by all studies identifying a lack of knowledge as a key barrier to screening attendance. CONCLUSIONS: BAME women have disproportionally lower breast screening attendance and a lack of knowledge is an essential barrier to overcome when addressing this health inequality.


Asunto(s)
Neoplasias de la Mama/psicología , Asistencia Sanitaria Culturalmente Competente , Etnicidad/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud/etnología , Promoción de la Salud/métodos , Accesibilidad a los Servicios de Salud , Disparidades en el Estado de Salud , Mamografía/psicología , Adulto , Negro o Afroamericano , Pueblo Asiatico , Población Negra , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/etnología , Cultura , Detección Precoz del Cáncer , Etnicidad/psicología , Femenino , Humanos , Aceptación de la Atención de Salud/etnología
14.
Clin Microbiol Rev ; 32(4)2019 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-31366609

RESUMEN

The technical genesis and practice of 8-aminoquinoline therapy of latent malaria offer singular scientific, clinical, and public health insights. The 8-aminoquinolines brought revolutionary scientific discoveries, dogmatic practices, benign neglect, and, finally, enduring promise against endemic malaria. The clinical use of plasmochin-the first rationally synthesized blood schizontocide and the first gametocytocide, tissue schizontocide, and hypnozoitocide of any kind-commenced in 1926. Plasmochin became known to sometimes provoke fatal hemolytic crises. World War II delivered a newer 8-aminoquinoline, primaquine, and the discovery of glucose-6-phosphate dehydrogenase (G6PD) deficiency as the basis of its hemolytic toxicity came in 1956. Primaquine nonetheless became the sole therapeutic option against latent malaria. After 40 years of fitful development, in 2018 the U.S. Food and Drug Administration registered the 8-aminoquinoline called tafenoquine for the prevention of all malarias and the treatment of those that relapse. Tafenoquine also cannot be used in G6PD-unknown or -deficient patients. The hemolytic toxicity of the 8-aminoquinolines impedes their great potential, but this problem has not been a research priority. This review explores the complex technical dimensions of the history of 8-aminoquinolines. The therapeutic principles thus examined may be leveraged in improved practice and in understanding the bright prospect of discovery of newer drugs that cannot harm G6PD-deficient patients.


Asunto(s)
Aminoquinolinas/uso terapéutico , Malaria/tratamiento farmacológico , Antimaláricos/uso terapéutico , Humanos
15.
Artículo en Inglés | MEDLINE | ID: mdl-33077656

RESUMEN

For a long while, 8-aminoquinoline compounds have been the only therapeutic agents against latent hepatic malaria parasites. These have poor activity against the blood-stage plasmodia causing acute malaria and must be used in conjunction with partner blood schizontocidal agents. We examined the impacts of one such agent, chloroquine, upon the activity of primaquine, an 8-aminoquinoline, against hepatic stages of Plasmodium cynomolgi, Plasmodium yoelii, Plasmodium berghei, and Plasmodium falciparum within several ex vivo systems-primary hepatocytes of Macaca fascicularis, primary human hepatocytes, and stably transformed human hepatocarcinoma cell line HepG2. Primaquine exposures to formed hepatic schizonts and hypnozoites of P. cynomolgi in primary simian hepatocytes exhibited similar 50% inhibitory concentration (IC50) values near 0.4 µM, whereas chloroquine in the same system exhibited no inhibitory activities. Combining chloroquine and primaquine in this system decreased the observed primaquine IC50 for all parasite forms in a chloroquine dose-dependent manner by an average of 18-fold. Chloroquine also decreased the primaquine IC50 against hepatic P. falciparum in primary human hepatocytes, P. berghei in simian primary hepatocytes, and P. yoelii in primary human hepatocytes. Chloroquine had no impact on primaquine IC50 against P. yoelii in HepG2 cells and, likewise, had no impact on the IC50 of atovaquone (hepatic schizontocide) against P. falciparum in human hepatocytes. We describe important sources of variability in the potentiation of primaquine activity by chloroquine in these systems. Chloroquine potentiated primaquine activity against hepatic forms of several plasmodia. We conclude that chloroquine specifically potentiated 8-aminoquinoline activities against active and dormant hepatic-stage plasmodia in normal primary hepatocytes but not in a hepatocarcinoma cell line.


Asunto(s)
Antimaláricos , Malaria , Plasmodium , Animales , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Cloroquina/farmacología , Cloroquina/uso terapéutico , Humanos , Malaria/tratamiento farmacológico , Primaquina/farmacología , Primaquina/uso terapéutico
16.
Lancet ; 394(10202): 929-938, 2019 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-31327563

RESUMEN

BACKGROUND: Primaquine is the only widely used drug that prevents Plasmodium vivax malaria relapses, but adherence to the standard 14-day regimen is poor. We aimed to assess the efficacy of a shorter course (7 days) of primaquine for radical cure of vivax malaria. METHODS: We did a randomised, double-blind, placebo-controlled, non-inferiority trial in eight health-care clinics (two each in Afghanistan, Ethiopia, Indonesia, and Vietnam). Patients (aged ≥6 months) with normal glucose-6-phosphate dehydrogenase (G6PD) and presenting with uncomplicated vivax malaria were enrolled. Patients were given standard blood schizontocidal treatment and randomly assigned (2:2:1) to receive 7 days of supervised primaquine (1·0 mg/kg per day), 14 days of supervised primaquine (0·5 mg/kg per day), or placebo. The primary endpoint was the incidence rate of symptomatic P vivax parasitaemia during the 12-month follow-up period, assessed in the intention-to-treat population. A margin of 0·07 recurrences per person-year was used to establish non-inferiority of the 7-day regimen compared with the 14-day regimen. This trial is registered at ClinicalTrials.gov (NCT01814683). FINDINGS: Between July 20, 2014, and Nov 25, 2017, 2336 patients were enrolled. The incidence rate of symptomatic recurrent P vivax malaria was 0·18 (95% CI 0·15 to 0·21) recurrences per person-year for 935 patients in the 7-day primaquine group and 0·16 (0·13 to 0·18) for 937 patients in the 14-day primaquine group, a difference of 0·02 (-0·02 to 0·05, p=0·3405). The incidence rate for 464 patients in the placebo group was 0·96 (95% CI 0·83 to 1·08) recurrences per person-year. Potentially drug-related serious adverse events within 42 days of starting treatment were reported in nine (1·0%) of 935 patients in the 7-day group, one (0·1%) of 937 in the 14-day group and none of 464 in the control arm. Four of the serious adverse events were significant haemolysis (three in the 7-day group and one in the 14-day group). INTERPRETATION: In patients with normal G6PD, 7-day primaquine was well tolerated and non-inferior to 14-day primaquine. The short-course regimen might improve adherence and therefore the effectiveness of primaquine for radical cure of P vivax malaria. FUNDING: UK Department for International Development, UK Medical Research Council, UK National Institute for Health Research, and the Wellcome Trust through the Joint Global Health Trials Scheme (MR/K007424/1) and the Bill & Melinda Gates Foundation (OPP1054404).


Asunto(s)
Antimaláricos/administración & dosificación , Malaria Vivax/tratamiento farmacológico , Primaquina/administración & dosificación , Adolescente , Adulto , Antimaláricos/efectos adversos , Antimaláricos/uso terapéutico , Niño , Preescolar , Método Doble Ciego , Esquema de Medicación , Estudios de Equivalencia como Asunto , Femenino , Estudios de Seguimiento , Humanos , Malaria Vivax/parasitología , Masculino , Cumplimiento de la Medicación/estadística & datos numéricos , Parasitemia/tratamiento farmacológico , Parasitemia/parasitología , Plasmodium vivax/aislamiento & purificación , Primaquina/efectos adversos , Primaquina/uso terapéutico , Recurrencia , Prevención Secundaria/métodos , Adulto Joven
17.
Lancet ; 394(10195): 332-343, 2019 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-31229233

RESUMEN

BACKGROUND: Plasmodium vivax exacts a significant toll on health worldwide, yet few efforts to date have quantified the extent and temporal trends of its global distribution. Given the challenges associated with the proper diagnosis and treatment of P vivax, national malaria programmes-particularly those pursuing malaria elimination strategies-require up to date assessments of P vivax endemicity and disease impact. This study presents the first global maps of P vivax clinical burden from 2000 to 2017. METHODS: In this spatial and temporal modelling study, we adjusted routine malariometric surveillance data for known biases and used socioeconomic indicators to generate time series of the clinical burden of P vivax. These data informed Bayesian geospatial models, which produced fine-scale predictions of P vivax clinical incidence and infection prevalence over time. Within sub-Saharan Africa, where routine surveillance for P vivax is not standard practice, we combined predicted surfaces of Plasmodium falciparum with country-specific ratios of P vivax to P falciparum. These results were combined with surveillance-based outputs outside of Africa to generate global maps. FINDINGS: We present the first high-resolution maps of P vivax burden. These results are combined with those for P falciparum (published separately) to form the malaria estimates for the Global Burden of Disease 2017 study. The burden of P vivax malaria decreased by 41·6%, from 24·5 million cases (95% uncertainty interval 22·5-27·0) in 2000 to 14·3 million cases (13·7-15·0) in 2017. The Americas had a reduction of 56·8% (47·6-67·0) in total cases since 2000, while South-East Asia recorded declines of 50·5% (50·3-50·6) and the Western Pacific regions recorded declines of 51·3% (48·0-55·4). Europe achieved zero P vivax cases during the study period. Nonetheless, rates of decline have stalled in the past five years for many countries, with particular increases noted in regions affected by political and economic instability. INTERPRETATION: Our study highlights important spatial and temporal patterns in the clinical burden and prevalence of P vivax. Amid substantial progress worldwide, plateauing gains and areas of increased burden signal the potential for challenges that are greater than expected on the road to malaria elimination. These results support global monitoring systems and can inform the optimisation of diagnosis and treatment where P vivax has most impact. FUNDING: Bill & Melinda Gates Foundation and the Wellcome Trust.


Asunto(s)
Enfermedades Endémicas/estadística & datos numéricos , Malaria Vivax/epidemiología , África/epidemiología , Américas/epidemiología , Asia Sudoriental/epidemiología , Teorema de Bayes , Salud Global , Humanos , Oceanía/epidemiología , Vigilancia de la Población , Análisis Espacio-Temporal
18.
Phys Rev Lett ; 125(13): 131101, 2020 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-33034506

RESUMEN

The quantum radiation pressure and the quantum shot noise in laser-interferometric gravitational wave detectors constitute a macroscopic manifestation of the Heisenberg inequality. If quantum shot noise can be easily observed, the observation of quantum radiation pressure noise has been elusive, so far, due to the technical noise competing with quantum effects. Here, we discuss the evidence of quantum radiation pressure noise in the Advanced Virgo gravitational wave detector. In our experiment, we inject squeezed vacuum states of light into the interferometer in order to manipulate the quantum backaction on the 42 kg mirrors and observe the corresponding quantum noise driven displacement at frequencies between 30 and 70 Hz. The experimental data, obtained in various interferometer configurations, is tested against the Advanced Virgo detector quantum noise model which confirmed the measured magnitude of quantum radiation pressure noise.

19.
Malar J ; 19(1): 324, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32887612

RESUMEN

Microscopy performed on stained films of peripheral blood for detection, identification and quantification of malaria parasites is an essential reference standard for clinical trials of drugs, vaccines and diagnostic tests for malaria. The value of data from such research is greatly enhanced if this reference standard is consistent across time and geography. Adherence to common standards and practices is a prerequisite to achieve this. The rationale for proposed research standards and procedures for the preparation, staining and microscopic examination of blood films for malaria parasites is presented here with the aim of improving the consistency and reliability of malaria microscopy performed in such studies. These standards constitute the core of a quality management system for clinical research studies employing microscopy as a reference standard. They can be used as the basis for the design of training and proficiency testing programmes as well as for procedures and quality assurance of malaria microscopy in clinical research.


Asunto(s)
Malaria/parasitología , Microscopía/métodos , Pruebas Diagnósticas de Rutina/métodos , Pruebas Diagnósticas de Rutina/normas , Humanos , Ensayos de Aptitud de Laboratorios/métodos , Ensayos de Aptitud de Laboratorios/normas , Microscopía/normas , Control de Calidad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Coloración y Etiquetado/métodos , Coloración y Etiquetado/normas
20.
J Immunol ; 201(2): 432-439, 2018 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-29848753

RESUMEN

Viral respiratory tract infections (VRTI) remain a leading cause of morbidity and mortality among infants and young children. In mice, optimal protection to VRTI is mediated by recruitment of effector T cells to the lungs and respiratory tract, and subsequent establishment of tissue resident memory T cells (Trm), which provide long-term protection. These critical processes of T cell recruitment to the respiratory tract, their role in disease pathogenesis, and establishment of local protective immunity remain undefined in pediatric VRTI. In this study, we investigated T cell responses in the upper respiratory tract (URT) and lower respiratory tract (LRT) of infants and young children with VRTI, revealing developmental regulation of T cell differentiation and Trm generation in situ. We show a direct concurrence between T cell responses in the URT and LRT, including a preponderance of effector CD8+ T cells that was associated with disease severity. During infant VRTI, there was an accumulation of terminally differentiated effector cells (effector memory RA+ T cells) in the URT and LRT with reduced Trm in the early neonatal period, and decreased effector memory RA+ T cell and increased Trm formation with age during the early years of childhood. Moreover, human infant T cells exhibit increased expression of the transcription factor T-bet compared with adult T cells, suggesting a mechanism for preferential generation of effector over Trm. The developmental regulation of respiratory T cell responses as revealed in the present study is important for diagnosing, monitoring, and treating VRTI in the critical early life stages.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Memoria Inmunológica/inmunología , Infecciones del Sistema Respiratorio/inmunología , Virosis/inmunología , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Pulmón/inmunología , Pulmón/virología , Activación de Linfocitos/inmunología , Masculino , Infecciones del Sistema Respiratorio/virología , Factores de Transcripción/inmunología
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