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1.
Air Med J ; 39(5): 410-413, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33012481

RESUMEN

OBJECTIVE: Suboptimal ventilation may impact outcomes in patients with traumatic brain injury (TBI). This study compares the incidence of eucapnia between manually and mechanically ventilated patients with severe TBI during helicopter transport. METHODS: This retrospective chart review included consecutive intubated adults with severe TBI (Glasgow Coma Scale score < 9) transported by helicopter from the scene of injury to a level 1 trauma center between 2009 and 2015. The primary outcome was the first venous partial pressure of carbon dioxide obtained in the emergency department. Hypocapnia, eucapnia, and hypercapnia were defined based on the normal range for the testing instrument. The Fisher exact test was used to compare groups. RESULTS: Of 1,070 trauma patients intubated and transported, 93 met the inclusion criteria with full data. The mean age was 43 years, 81 of 93 were white, and 70 of 93 were men. The mean Injury Severity Score was 29, and 26 of 93 were mechanically ventilated. Hypocapnia occurred in 4 of 93 and hypercapnia in 56 of 93. There was no difference in the rate of eucapnia in manually ventilated compared with mechanically ventilated patients (36% vs. 35%, P = 1.00). CONCLUSION: Eucapnia at emergency department arrival occurred in 36% of patients and was unaffected by whether ventilation was manually or mechanically controlled. Few patients were hypocapnic, indicating a low incidence of hyperventilation during helicopter transport.


Asunto(s)
Lesiones Traumáticas del Encéfalo/terapia , Servicios Médicos de Urgencia , Respiración Artificial , Adulto , Australia , Lesiones Traumáticas del Encéfalo/fisiopatología , Femenino , Humanos , Masculino , Auditoría Médica , Persona de Mediana Edad , Estudios Retrospectivos , Índices de Gravedad del Trauma , Adulto Joven
2.
Front Microbiol ; 15: 1346068, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38362501

RESUMEN

Lymphatic filariasis and onchocerciasis are two major neglected tropical diseases that are responsible for causing severe disability in 50 million people worldwide, whilst veterinary filariasis (heartworm) is a potentially lethal parasitic infection of companion animals. There is an urgent need for safe, short-course curative (macrofilaricidal) drugs to eliminate these debilitating parasite infections. We investigated combination treatments of the novel anti-Wolbachia azaquinazoline small molecule, AWZ1066S, with benzimidazole drugs (albendazole or oxfendazole) in up to four different rodent filariasis infection models: Brugia malayi-CB.17 SCID mice, B. malayi-Mongolian gerbils, B. pahangi-Mongolian gerbils, and Litomosoides sigmodontis-Mongolian gerbils. Combination treatments synergised to elicit threshold (>90%) Wolbachia depletion from female worms in 5 days of treatment, using 2-fold lower dose-exposures of AWZ1066S than monotherapy. Short-course lowered dose AWZ1066S-albendazole combination treatments also delivered partial adulticidal activities and/or long-lasting inhibition of embryogenesis, resulting in complete transmission blockade in B. pahangi and L. sigmodontis gerbil models. We determined that short-course AWZ1066S-albendazole co-treatment significantly augmented the depletion of Wolbachia populations within both germline and hypodermal tissues of B. malayi female worms and in hypodermal tissues in male worms, indicating that anti-Wolbachia synergy is not limited to targeting female embryonic tissues. Our data provides pre-clinical proof-of-concept that sub-seven-day combinations of rapid-acting novel anti-Wolbachia agents with benzimidazole anthelmintics are a promising curative and transmission-blocking drug treatment strategy for filarial diseases of medical and veterinary importance.

3.
Sci Adv ; 9(15): eadf5493, 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37058570

RESUMEN

The Hunga Tonga-Hunga Ha'apai (HTHH) volcanic eruption in January 2022 generated catastrophic tsunami and contends for the largest natural explosion in more than a century. The main island, Tongatapu, suffered waves up to 17 m, and Tofua Island suffered waves up to 45 m, comfortably placing HTHH in the "megatsunami" league. We present a tsunami simulation of the Tongan Archipelago calibrated by field observations, drone, and satellite data. Our simulation emphasizes how the complex shallow bathymetry of the area acted as a low-velocity wave trap, capturing tsunami for more than 1 hour. Despite its size and long duration, few lives were lost. Simulation suggests that HTHH's location relative to urban centers saved Tonga from a worse outcome. Whereas 2022 seems to have been a lucky escape, other oceanic volcanoes have the capacity to spawn future tsunami at HTHH scale. Our simulation amplifies the state of understanding of volcanic explosion tsunami and provides a framework for assessment of future hazards.

5.
Circulation ; 122(15): 1464-9, 2010 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-20876439

RESUMEN

BACKGROUND: Among individuals experiencing an ST segment-elevation myocardial infarction, current guidelines recommend that the interval from first medical contact to percutaneous coronary intervention be ≤90 minutes. The objective of this study was to determine whether prehospital time intervals were associated with ST-elevation myocardial infarction system performance, defined as first medical contact to percutaneous coronary intervention. METHODS AND RESULTS: Study patients presented with an acute ST-elevation myocardial infarction diagnosed by prehospital ECG between May 2007 and March 2009. Prehospital time intervals were as follows: 9-1-1 call receipt to ambulance on scene ≤10 minutes, ambulance on scene to 12-lead ECG acquisition ≤8 minutes, on-scene time ≤15 minutes, prehospital ECG acquisition to ST-elevation myocardial infarction team notification ≤10 minutes, and scene departure to patient on cardiac catheterization laboratory table ≤30 minutes. Time intervals were derived and analyzed with descriptive statistics and logistic regression. There were 181 prehospital patients who received percutaneous coronary intervention, with 165 (91.1) having complete data. Logistic regression indicated that table time, response time, and on-scene time were the benchmark time intervals with the greatest influence on the probability of achieving percutaneous coronary intervention in ≤90 minutes. Individuals with a time from scene departure to arrival on cardiac catheterization laboratory table of ≤30 minutes were 11.1 times (3.4 to 36.0) more likely to achieve percutaneous coronary intervention in ≤90 minutes than those with extended table times. CONCLUSIONS: In this patient population, prehospital timing benchmarks were associated with system performance. Although meeting all 5 benchmarks may be an ideal goal, this model may be more useful for identifying areas for system improvement that will have the greatest clinical impact.


Asunto(s)
Benchmarking/normas , Electrocardiografía , Servicios Médicos de Urgencia/normas , Infarto del Miocardio/terapia , Angioplastia de Balón Asistida por Láser , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , North Carolina , Evaluación de Resultado en la Atención de Salud , Estudios Retrospectivos , Factores de Tiempo , Estados Unidos
6.
Bioorg Med Chem Lett ; 21(15): 4512-5, 2011 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-21723121

RESUMEN

The synthesis (Pd-mediated coupling strategy) and characterization (NMR, IR, elemental analysis, etc.) of a short series of quinoline-oxazole hybrid compounds has been carried out. These materials are found to be moderately active against Plasmodium falciparum in vitro, with activities in the sub-micromolar range, and to display acceptable cytotoxicity to mononuclear leukocytes. Chemical modification strategies, with the intention to increase the biological potency of this new class of anti-malarial agents, are discussed.


Asunto(s)
Antimaláricos/síntesis química , Cloroquina/química , Plasmodium falciparum/efectos de los fármacos , Antimaláricos/química , Antimaláricos/farmacología , Cloroquina/síntesis química , Cloroquina/farmacología , Modelos Biológicos , Oxazoles/química , Quinolinas/química
7.
Prehosp Emerg Care ; 15(3): 366-70, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21480775

RESUMEN

INTRODUCTION: The availability of ambulances to respond to emergency calls is related to their ability to return to service from the hospital. Extended hospital turnaround times decrease the number of available unit hours ambulances are deployed, which in turn can increase coverage costs or sacrifice coverage. OBJECTIVE: To determine whether ambulance turnaround times were associated with patient acuity, destination hospital, and time of day. METHODS: This retrospective analysis of ambulance hospital turnaround times utilized 12 months of data from a single, countywide, metropolitan emergency medical services (EMS) service. Turnaround time was defined as the interval between the time of ambulance arrival at the hospital and the time the ambulance became available to respond to another call. Independent variables included patient acuity (low [BLS nonemergency transport], medium [ALS care and nonemergency transport], and high [ALS care and emergency transport]), destination hospital (seven regional hospitals), and time of day (one-hour intervals). Data analysis consisted of descriptive statistics, t-tests, and linear regression. RESULTS: Of the 61,094 patient transports, the mean turnaround time was 35.6 minutes (standard deviation [SD] = 16.5). Turnaround time was significantly associated with patient acuity (p < 0.001). High-acuity calls had a mean turnaround time of 52.5 minutes (SD = 21.5), whereas moderate-acuity and low-acuity calls had mean turnaround times of 42.0 minutes (SD = 16.4) and 32.5 minutes (SD = 14.4), respectively. A statistically significant relationship between destination hospital and turnaround time was found, with the differences in means ranging from 30 seconds to 8 minutes. Similarly, time of day was associated with turnaround time, with the longest turnaround times occurring between 0600 and 1500 hours. CONCLUSION: This study demonstrated that patient acuity, destination hospital, and time of day were associated with variation in ambulance turnaround times. Research describing other system characteristics such as current emergency department census and patient handoff procedures may further demonstrate areas for improvement in HTAT. Results from this analysis may be used to inspire EMS administrators and EMS medical directors to start tracking these times to create a predictive model of EMS staffing needs.


Asunto(s)
Ambulancias/estadística & datos numéricos , Sistemas de Comunicación entre Servicios de Urgencia/estadística & datos numéricos , Servicios Médicos de Urgencia/estadística & datos numéricos , Servicio de Urgencia en Hospital/estadística & datos numéricos , Intervalos de Confianza , Conducta Cooperativa , Accesibilidad a los Servicios de Salud , Humanos , Modelos Lineales , North Carolina , Estudios Retrospectivos , Texas , Tiempo
8.
J Allergy Clin Immunol ; 125(1): 203-8, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19944455

RESUMEN

BACKGROUND: CD4(+)T lymphocyte measurements are the most important indicator of mortality in HIV-infected individuals in resource-limited settings. There is currently a lack of comprehensive immunophenotyping data from African populations to guide the immunologic assessment of HIV infection. OBJECTIVE: To quantify variation in absolute and relative lymphocyte subsets with age in healthy Malawians. METHODS: Lymphocyte subsets in peripheral blood of 539 healthy HIV-uninfected Malawians stratified by age were enumerated by flow cytometry. RESULTS: B and T-lymphocyte and T-lymphocyte subset absolute concentrations peaked in early childhood then decreased to adult levels, whereas lymphocyte subset proportions demonstrated much less variation with age. Adult lymphocyte subsets were similar to those in developed countries. In contrast, high B-lymphocyte and CD8(+)T-lymphocyte levels among children under 2 years, relative to those in developed countries, resulted in low CD4(+)T-lymphocyte percentages that varied little between 0 and 5 years (35% to 39%). The CD4(+)T-lymphocyte percentages in 35% of healthy children under 1 year and 18% of children age 1 to 3 years were below the World Health Organization threshold defining immunodeficiency in HIV-infected children in resource-limited settings. Thirteen percent of healthy children under 18 months old had a CD4:CD8T-lymphocyte ratio <1.0, which is commonly associated with HIV infection. All immunologic parameters except absolute natural killer lymphocyte concentration varied significantly with age, and percentage and overall absolute CD4(+)T-lymphocyte counts were higher in females than males. CONCLUSION: Although lymphocyte subsets in Malawian adults are similar to those from developed countries, CD4(+)T-lymphocyte percentages in young children are comparatively low. These findings need to be considered when assessing the severity of HIV-related immunodeficiency in African children under 3 years.


Asunto(s)
Subgrupos de Linfocitos B/inmunología , Subgrupos Linfocitarios/inmunología , Subgrupos de Linfocitos T/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Recuento de Linfocito CD4 , Niño , Preescolar , Femenino , Citometría de Flujo , Infecciones por VIH/inmunología , Humanos , Inmunofenotipificación , Lactante , Recién Nacido , Malaui , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Hum Reprod ; 25(4): 824-38, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20139429

RESUMEN

This article reports the results of the most recent in a series of EHSRE workshops designed to synthesize the current state of the field in Andrology and provide recommendations for future work (for details see Appendix). Its focus is on methods for detecting sperm DNA damage and potential application of new knowledge about sperm chromatin organization, vulnerability and repair to improve the diagnosis and treatment of clinical infertility associated with that damage. Equally important is the use and reliability of these tests to identify the extent to which environmental contaminants or pharmaceutical agents may contribute to the incidence of sperm DNA damage and male fertility problems. A working group (for workshop details, see Appendix) under the auspices of ESHRE met in May 2009 to assess the current knowledgebase and suggest future basic and clinical research directions. This document presents a synthesis of the working group's understanding of the recent literature and collective discussions on the current state of knowledge of sperm chromatin structure and function during fertilization. It highlights the biological, assay and clinical uncertainties that require further research and ends with a series of 5 key recommendations.


Asunto(s)
Daño del ADN , ADN/genética , Espermatozoides/metabolismo , Animales , Cromatina/genética , Reparación del ADN , Contaminantes Ambientales/toxicidad , Epigénesis Genética , Europa (Continente) , Femenino , Fertilización/genética , Fertilización/fisiología , Humanos , Infertilidad Masculina/diagnóstico , Infertilidad Masculina/genética , Infertilidad Masculina/terapia , Masculino , Embarazo , Sociedades Médicas , Espermatozoides/efectos de los fármacos , Zinc/metabolismo
11.
J Orthod ; 37(1): 6-15, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20439922

RESUMEN

OBJECTIVE: To screen patients with oligoarticular and polyarticular forms of Juvenile Idiopathic Arthritis (JIA) to determine (i) the severity of their class II skeletal pattern; (ii) temporomandibular joint signs and symptoms and (iii) use of systemic corticosteroids. DESIGN: Cross-sectional screening. SUBJECTS AND SETTING: Sixty-eight children with JIA aged between 9 and 16 years old who were screened at four regional treatment centres in the UK. METHOD: Patients were screened clinically and radiographically for the presence of class II skeletal pattern and temporomandibular (TMJ) pain dysfunction syndrome. In addition, the JIA sub-type and history of disease activity and medication were recorded. MAIN OUTCOME MEASURES: Class II skeletal pattern, TMJ signs and symptoms, use of systemic corticosteroids. RESULTS: The mean ANB values were 4.2 degrees (SD = 2.9 degrees) in the oligoarticular group and 5.1 degrees (SD = 3.8 degrees) in the polyarticular group. Just under one-third of children had a moderate or severe class II skeletal pattern and a further quarter of children had a mild class II skeletal pattern. Clinical signs and symptoms of temporomandibular joint pain dysfunction syndrome were low (<20%), except for crepitus and click which affected between 24 and 40% of JIA children. Radiographically, 57% of oligoarticular and 77% of polyarticular cases exhibited condylar erosion. Use of systemic corticosteroids varied between centres, but overall, was prescribed more in polyarticular cases (P = 0.001). CONCLUSIONS: Just under one-third of oligoarticular and polyarticular JIA patients exhibited a moderate or severe class II skeletal pattern. It is, therefore, likely that any future clinical trial to investigate the effect of functional appliance treatment in JIA patients, will need multicentre co-operation to fulfil potential sample size requirements. Clinical signs and symptoms of temporomandibular joint pain dysfunction syndrome were low except for crepitus and click. However, radiographic evidence of condylar erosion was high particularly in the polyarticular group. Use of systemic corticosteroids was prescribed more in polyarticular cases and this is likely to reflect the severity of the disease.


Asunto(s)
Corticoesteroides/uso terapéutico , Artritis Juvenil/complicaciones , Artritis Juvenil/tratamiento farmacológico , Glucocorticoides/uso terapéutico , Maloclusión Clase II de Angle/patología , Síndrome de la Disfunción de Articulación Temporomandibular/patología , Adolescente , Artritis Juvenil/clasificación , Cefalometría , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/etiología , Cóndilo Mandibular/patología , Radiografía , Síndrome de la Disfunción de Articulación Temporomandibular/diagnóstico por imagen , Síndrome de la Disfunción de Articulación Temporomandibular/etiología
12.
Respir Care ; 65(1): 1-10, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31882412

RESUMEN

BACKGROUND: COPD exacerbations lead to accelerated decline in lung function, poor quality of life, and increased mortality and cost. Emergency department (ED) observation units provide short-term care to reduce hospitalizations and cost. Strategies to improve outcomes in ED observation units following COPD exacerbations are needed. We sought to reduce 30-d ED revisits for COPD exacerbations managed in ED observation units through implementation of a COPD care bundle. The study setting was an 800-bed, academic, safety-net hospital with 700 annual ED encounters for COPD exacerbations. Among those discharged from ED observation unit, the 30-d all-cause ED revisit rate (ie, the outcome measure) was 49% (baseline period: August 2014 through September 2016). METHODS: All patients admitted to the ED observation unit with COPD exacerbations were included. A multidisciplinary team implemented the COPD bundle using iterative plan-do-study-act cycles with a goal adherence of 90% (process measure). The bundle, adopted from our inpatient program, was developed using care-delivery failures and unmet subject needs. It included 5 components: appropriate inhaler regimen, 30-d inhaler supply, education on devices available after discharge, standardized discharge instructions, and a scheduled 15-d appointment. We used statistical process-control charts for process and outcome measures. To compare subject characteristics and process features, we sampled consecutive patients from the baseline (n = 50) and postbundle (n = 83) period over 5-month and 7-month intervals, respectively. Comparisons were made using t tests and chi-square tests with P < .05 significance. RESULTS: During baseline and postbundle periods, 410 and 165 subjects were admitted to the ED observation unit, respectively. After iterative plan-do-study-act cycles, bundle adherence reached 90% in 6 months, and the 30-d ED revisit rate declined from 49% to 30% (P = .003) with a system shift on statistical process-control charts. There was no difference in hospitalization rate from ED observation unit (45% vs 51%, P = .16). Subject characteristics were similar in the baseline and postbundle periods. CONCLUSIONS: Reliable adherence to a COPD care bundle reduced 30-d ED revisits among those treated in the ED observation unit.


Asunto(s)
Unidades de Observación Clínica/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Paquetes de Atención al Paciente/estadística & datos numéricos , Readmisión del Paciente/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/terapia , Anciano , Protocolos Clínicos , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Alta del Paciente/estadística & datos numéricos
13.
PLoS One ; 15(12): e0243619, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33362214

RESUMEN

Tsunami events in antiquity had a profound influence on coastal societies. Six thousand years of historical records and geological data show that tsunamis are a common phenomenon affecting the eastern Mediterranean coastline. However, the possible impact of older tsunamis on prehistoric societies has not been investigated. Here we report, based on optically stimulated luminescence chronology, the earliest documented Holocene tsunami event, between 9.91 to 9.29 ka (kilo-annum), from the eastern Mediterranean at Dor, Israel. Tsunami debris from the early Neolithic is composed of marine sand embedded within fresh-brackish wetland deposits. Global and local sea-level curves for the period, 9.91-9.29 ka, as well as surface elevation reconstructions, show that the tsunami had a run-up of at least ~16 m and traveled between 3.5 to 1.5 km inland from the palaeo-coastline. Submerged slump scars on the continental slope, 16 km west of Dor, point to the nearby "Dor-complex" as a likely cause. The near absence of Pre-Pottery Neolithic A-B archaeological sites (11.70-9.80 cal. ka) suggest these sites were removed by the tsunami, whereas younger, late Pre-Pottery Neolithic B-C (9.25-8.35 cal. ka) and later Pottery-Neolithic sites (8.25-7.80 cal. ka) indicate resettlement following the event. The large run-up of this event highlights the disruptive impact of tsunamis on past societies along the Levantine coast.


Asunto(s)
Tsunamis , Arqueología , Sedimentos Geológicos/análisis , Historia Antigua , Humanos , Israel , Mediciones Luminiscentes , Tsunamis/historia
14.
Bioorg Med Chem Lett ; 18(5): 1720-4, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18243702

RESUMEN

Here we present an efficient route into synthetically challenging bridged 1,2,4,5-tetraoxanes. The key to the success of this route is the use of H(2)O(2) and catalytic I(2) to form the gem-dihydroperoxide followed by a Ag(2)O mediated alkylation using 1,3-diiodopropane. Using this methodology a range of bridged tetraoxanes which display good in vitro antimalarial activity were synthesized.


Asunto(s)
Antimaláricos/química , Antimaláricos/farmacología , Tetraoxanos/química , Tetraoxanos/farmacología , Animales , Arteméter , Artemisininas/química , Artemisininas/farmacología , Estructura Molecular , Plasmodium falciparum/efectos de los fármacos , Relación Estructura-Actividad
16.
Trans R Soc Trop Med Hyg ; 100(2): 184-6, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16289166

RESUMEN

A patient admitted with severe Plasmodium falciparum malaria in western Thailand had an early treatment failure with quinine, despite full dosing. Plasma quinine concentrations were subtherapeutic. Abnormal quinine pharmacokinetics may explain sporadic reports of quinine treatment failures in severe malaria.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Quinina/uso terapéutico , Antimaláricos/sangre , Antimaláricos/farmacocinética , Humanos , Masculino , Quinina/sangre , Quinina/farmacocinética , Tailandia , Insuficiencia del Tratamiento
18.
Clin Vaccine Immunol ; 23(2): 95-103, 2015 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-26581890

RESUMEN

Lymphocytes are implicated in immunity and pathogenesis of severe malaria. Since lymphocyte subsets vary with age, assessment of their contribution to different etiologies can be difficult. We immunophenotyped peripheral blood from Malawian children presenting with cerebral malaria, severe malarial anemia, and uncomplicated malaria (n = 113) and healthy aparasitemic children (n = 42) in Blantyre, Malawi, and investigated lymphocyte subset counts, activation, and memory status. Children with cerebral malaria were older than those with severe malarial anemia. We found panlymphopenia in children presenting with cerebral malaria (median lymphocyte count, 2,100/µl) and uncomplicated malaria (3,700/µl), which was corrected in convalescence and was absent in severe malarial anemia (5,950/µl). Median percentages of activated CD69(+) NK (73%) and γδ T (60%) cells were higher in cerebral malaria than in other malaria types. Median ratios of memory to naive CD4(+) lymphocytes were higher in cerebral malaria than in uncomplicated malaria and low in severe malarial anemia. The polarized lymphocyte subset profiles of different forms of severe malaria are independent of age. In conclusion, among Malawian children cerebral malaria is characterized by lymphocyte activation and increased memory cells, consistent with immune priming. In contrast, there are reduced memory cells and less activation in severe malaria anemia. Further studies are required to understand whether these immunological profiles indicate predisposition of some children to one or another form of severe malaria.


Asunto(s)
Memoria Inmunológica , Activación de Linfocitos , Subgrupos Linfocitarios/inmunología , Malaria Cerebral/inmunología , Malaria Falciparum/inmunología , Subgrupos de Linfocitos T/inmunología , Anemia/epidemiología , Anemia/inmunología , Anemia/mortalidad , Anemia/parasitología , Niño , Preescolar , Susceptibilidad a Enfermedades , Femenino , Humanos , Lactante , Recuento de Linfocitos , Malaria Cerebral/epidemiología , Malaria Cerebral/mortalidad , Malaria Cerebral/parasitología , Malaria Falciparum/complicaciones , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaui/epidemiología , Masculino
19.
Microbes Infect ; 4(2): 157-64, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11880047

RESUMEN

Africa carries the greatest burden of disease caused by Plasmodium falciparum, and we can expect this burden to rise in the near future, mainly because of drug resistance. Although effective drugs are available (such as artemether-lumefantrine, mefloquine, atovaquone-proguanil and halofantrine) they are uniformly too expensive for routine use. Affordable options include chloroquine plus sulfadoxine-pyrimethamine (SP), amodiaquine (alone or in combination with SP) and chlorproguanil-dapsone. Artemisinin combination therapy may offer considerable advantages over alternative therapies, but its introduction faces considerable logistic difficulty.


Asunto(s)
Antimaláricos/farmacología , Resistencia a Medicamentos , Malaria/tratamiento farmacológico , Malaria/epidemiología , Plasmodium falciparum/efectos de los fármacos , África/epidemiología , Animales , Antimaláricos/farmacocinética , Antimaláricos/provisión & distribución , Antimaláricos/uso terapéutico , Culicidae , Vectores de Enfermedades , Política de Salud/economía , Política de Salud/legislación & jurisprudencia , Humanos , Programas Nacionales de Salud/economía , Programas Nacionales de Salud/legislación & jurisprudencia , Plasmodium falciparum/genética , Organización Mundial de la Salud
20.
Macromolecules ; 46(13): 5117-5132, 2013 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-23853391

RESUMEN

Three bis-benzoxazine monomers based on the aniline derivatives of bisphenol A (BA-a), bisphenol F (BF-a), and 3,3'-thiodiphenol (BT-a) are examined using a variety of spectroscopic, chromatographic, and thermomechanical techniques. The effect on the polymerization of the monomers is compared using two common compounds, 3,3'-thiodiphenol (TDP) and 3,3'-thiodipropionic acid (TDA), at a variety of loadings. It is found that the diacid has a greater effect on reducing the onset of polymerization and increasing cross-link density and Tg for a given benzoxazine. However, the addition of >5 wt % of the diacid had a detrimental effect on the cross-link density, Tg, and thermal stability of the polymer. The kinetics of the polymerization of BA-a were found to be well described using an autocatalytic model for which values of n = 1.64 and m = 2.31 were obtained for the early and later stages of reaction (activation energy = 81 kJ/mol). Following recrystallization the same monomer yielded values n = 1.89, m = 0.89, and Ea = 94 kJ/mol (confirming the influence of higher oligomers on reactivity). The choice of additive (in particular the magnitude of its pKa) appears to influence the nature of the network formation from a linear toward a more clusterlike growth mechanism.

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