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1.
Clin Infect Dis ; 78(2): 457-460, 2024 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-37897407

RESUMEN

Cerebral malaria is an important cause of mortality and neurodisability in endemic regions. We show magnetic resonance imaging (MRI) features suggestive of cytotoxic and vasogenic cerebral edema followed by microhemorrhages in 2 adult UK cases, comparing them with an Indian cohort. Long-term follow-up images correlate ongoing changes with residual functional impairment.


Asunto(s)
Edema Encefálico , Malaria Cerebral , Adulto , Humanos , Malaria Cerebral/diagnóstico por imagen , Imagen por Resonancia Magnética/efectos adversos , Imagen por Resonancia Magnética/métodos , Edema Encefálico/etiología , Edema Encefálico/patología
2.
Clin Infect Dis ; 75(1): 11-18, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34905777

RESUMEN

BACKGROUND: Cerebral malaria in adults is associated with brain hypoxic changes on magnetic resonance (MR) images and has a high fatality rate. Findings of neuroimaging studies suggest that brain involvement also occurs in patients with uncomplicated malaria (UM) or severe noncerebral malaria (SNCM) without coma, but such features were never rigorously characterized. METHODS: Twenty patients with UM and 21 with SNCM underwent MR imaging on admission and 44-72 hours later, as well as plasma analysis. Apparent diffusion coefficient (ADC) maps were generated, with values from 5 healthy individuals serving as controls. RESULTS: Patients with SNCM had a wide spectrum of cerebral ADC values, including both decreased and increased values compared with controls. Patients with low ADC values, indicating cytotoxic edema, showed hypoxic patterns similar to cerebral malaria despite the absence of deep coma. Conversely, high ADC values, indicative of mild vasogenic edema, were observed in both patients with SNCM and patients with UM. Brain involvement was confirmed by elevated circulating levels of S100B. Creatinine was negatively correlated with ADC in SNCM, suggesting an association between acute kidney injury and cytotoxic brain changes. CONCLUSIONS: Brain involvement is common in adults with SNCM and a subgroup of hospitalized patients with UM, which warrants closer neurological follow-up. Increased creatinine in SNCM may render the brain more susceptible to cytotoxic edema.


Asunto(s)
Edema Encefálico , Malaria Cerebral , Malaria Falciparum , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/etiología , Edema Encefálico/patología , Coma/complicaciones , Creatinina , Humanos , Malaria Cerebral/complicaciones , Malaria Falciparum/complicaciones
3.
Clin Infect Dis ; 73(7): e2387-e2396, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-33321516

RESUMEN

BACKGROUND: Cerebral malaria is a common presentation of severe Plasmodium falciparum infection and remains an important cause of death in the tropics. Key aspects of its pathogenesis are still incompletely understood, but severe brain swelling identified by magnetic resonance imaging (MRI) was associated with a fatal outcome in African children. In contrast, neuroimaging investigations failed to identify cerebral features associated with fatality in Asian adults. METHODS: Quantitative MRI with brain volume assessment and apparent diffusion coefficient (ADC) histogram analyses were performed for the first time in 65 patients with cerebral malaria to compare disease signatures between children and adults from the same cohort, as well as between fatal and nonfatal cases. RESULTS: We found an age-dependent decrease in brain swelling during acute cerebral malaria, and brain volumes did not differ between fatal and nonfatal cases across both age groups. In nonfatal disease, reversible, hypoxia-induced cytotoxic edema occurred predominantly in the white matter in children, and in the basal ganglia in adults. In fatal cases, quantitative ADC histogram analyses also demonstrated different end-stage patterns between adults and children: Severe hypoxia, evidenced by global ADC decrease and elevated plasma levels of lipocalin-2 and microRNA-150, was associated with a fatal outcome in adults. In fatal pediatric disease, our results corroborate an increase in brain volume, leading to augmented cerebral pressure, brainstem herniation, and death. CONCLUSIONS: Our findings suggest distinct pathogenic patterns in pediatric and adult cerebral malaria with a stronger cytotoxic component in adults, supporting the development of age-specific adjunct therapies.


Asunto(s)
Encefalopatías , Malaria Cerebral , Malaria Falciparum , Adulto , Encéfalo/diagnóstico por imagen , Encefalopatías/diagnóstico por imagen , Encefalopatías/parasitología , Niño , Humanos , Lipocalina 2/sangre , Imagen por Resonancia Magnética , Malaria Cerebral/diagnóstico por imagen , Malaria Falciparum/diagnóstico por imagen , MicroARNs/sangre
4.
Hemoglobin ; 42(4): 236-242, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30486691

RESUMEN

Hemoglobinopathies and thalassemias are the most commonly encountered monogenic disorders of blood in humans, posing a major genetic and public health problem round the globe. Hb S (HBB: c.20A>T)-ß-thalassemia (ß-thal) is a compound aberrant heterozygosity with inconsistent phenotypic expression, which are poorly described and clinically mapped. Comprehensive genetic characterization of such a population is highly warranted for complete understanding of the clinical heterogeneity, disease prognosis and therapeutic management. In this study, Hb S-ß-thal (n = 60) patients, strictly defined by varying degrees of clinical presentations, were selected to evaluate their genotype-phenotype agreement. Furthermore, ß-globin (n = 120) and α-globin gene clusters (n = 60) were genetically characterized and statistically correlated with clinical terminologies to explain the clinical heterogeneity. Our results revealed the association of the Arab-Indian haplotypes with nine different frameworks of ß-thal together with the modulating role of α-thalassemia (α-thal). The study subjects, including carriers of ß-thal haplotype III [- - - - - - -] (8.0%), presented with varying severe patterns of clinical symptoms such as painful crisis, multiple infections and splenomegaly, as an outcome of significantly less Hb F and higher Hb S levels (p < 0.5). The study findings indicated that together with α-thal, ß-thal haplotypes and Hb F levels, may possibly provide a close justification to support the clinical heterogeneity in the study population.


Asunto(s)
Haplotipos , Hemoglobina Falciforme/genética , Talasemia alfa , Talasemia beta/genética , Árabes , Hemoglobinopatías/etnología , Hemoglobinopatías/genética , Heterocigoto , Humanos , Fenotipo , Población Blanca , Talasemia beta/etnología
5.
Bioorg Med Chem Lett ; 26(4): 1342-7, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26810315

RESUMEN

Series of curcumin derivatives/analogues were designed and efficient method for synthesis thereof is described. All the synthesized compounds have been screened for their cytotoxicity and evaluated their antioxidant activity. Cytotoxicity effect has been evaluated against three cell lines Hep-G2, HCT-116 and QG-56 by MTT assay method. Structure activity relationship has revealed that particularly, compound 3c, (IC50 value 6.25 µM) has shown better cytotoxicity effect against three cell lines. According to results of SAR study, it was found that 4H-pyrimido[2,1-b]benzothiazole derivatives (2e and 2f), pyrazoles (3a, 3b, 3c and 3d) benzylidenes (4d) exhibited better antioxidant activity than curcumin. A correlation of structure and activities relationship of these compounds with respect to drug score profiles and other physico-chemical properties of drugs are described and verified experimentally.


Asunto(s)
Antioxidantes/química , Curcumina/química , Antioxidantes/síntesis química , Antioxidantes/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Curcumina/síntesis química , Curcumina/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Células HCT116 , Células Hep G2 , Humanos , Oxidación-Reducción , Relación Estructura-Actividad
6.
ScientificWorldJournal ; 2014: 593546, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25544957

RESUMEN

Relative quantification of algC gene expression was evaluated in the multidrug resistant strain Acinetobacter baumannii AIIMS 7 biofilm (3 to 96 h, on polystyrene surface) compared to the planktonic counterparts. Comparison revealed differential algC expression pattern with maximum 81.59-fold increase in biofilm cells versus 3.24-fold in planktonic cells (P < 0.05). Expression levels strongly correlated with specific biofilm stages (scale of 3 to 96 h), coinciding maximum at initial surface attachment stage (9 h) and biofilm maturation stage (48 h). Cloning, heterologous expression, and bioinformatics analyses indicated algC gene product as the bifunctional enzyme phosphomannomutase/phosphoglucomutase (PMM/PGM) of ∼ 53 kDa size, which augmented biofilms significantly in algC clones compared to controls (lacking algC gene), further localized by scanning electron microscopy. Moreover, molecular dynamics analysis on the three-dimensional structure of PMM/PGM (simulated up to 10 ns) revealed enzyme structure as stable and similar to that in P. aeruginosa (synthesis of alginate and lipopolysaccharide core) and involved in constitution of biofilm EPS (extracellular polymeric substances). Our observation on differential expression pattern of algC having strong correlation with important biofilm stages, scanning electron-microscopic evidence of biofilm augmentation taken together with predictive enzyme functions via molecular dynamic (MD) simulation, proposes a new basis of A. baumannii AIIMS 7 biofilm development on inanimate surfaces.


Asunto(s)
Acinetobacter baumannii/fisiología , Proteínas Bacterianas/biosíntesis , Biopelículas/crecimiento & desarrollo , Farmacorresistencia Bacteriana Múltiple/fisiología , Regulación Bacteriana de la Expresión Génica/fisiología , Poliestirenos/química , Propiedades de Superficie
7.
medRxiv ; 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36711482

RESUMEN

Durgama Anchalare Malaria Nirakaran (DAMaN) is a multi-component malaria intervention for hard-to-reach villages in Odisha, India. The main component, Malaria Camps (MCs), consists of mass screening, treatment, education, and intensified vector control. We evaluated MC effectiveness using a quasi-experimental cluster-assigned stepped-wedge study with a pretest-posttest control group in 15 villages: six immediate (Arm A), six delayed (Arm B), and three previous interventions (Arm C). The primary outcome was PCR+ Plasmodium infection prevalence. Across all arms, the odds of PCR+ malaria were 54% lower at the third follow-up compared to baseline. A time (i.e., visit) x study arm interaction revealed significantly lower odds of PCR+ malaria in Arm A versus B at the third follow-up. The cost per person ranged between US$3-8, the cost per tested US$4-7, and the cost per treated US$82-1,614, per camp round. These results suggest that the DAMaN intervention is a promising, financially feasible approach for malaria control.

8.
Sci Rep ; 13(1): 22998, 2023 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-38155156

RESUMEN

Durgama Anchalare Malaria Nirakaran (DAMaN) is a multi-component malaria intervention for hard-to-reach villages in Odisha, India. The main component, malaria camps (MCs), consists of mass screening, treatment, education, and intensified vector control. We evaluated MC effectiveness using a quasi-experimental cluster-assigned stepped-wedge study with a pretest-posttest control group in 15 villages: six immediate (Arm A), six delayed (Arm B), and three previous interventions (Arm C). The primary outcome was PCR + Plasmodium infection prevalence. The time (i.e., baseline vs. follow-up 3) x study arm interaction term shows that there were statistically significant lower odds of PCR + Plasmodium infection in Arm A (AOR = 0.36, 95% CI = 0.17, 0.74) but not Arm C as compared to Arm B at the third follow-up. The cost per person ranged between US$3-8, the cost per tested US$4-9, and the cost per treated US$82-1,614, per camp round. These results suggest that the DAMaN intervention is a promising and financially feasible approach for malaria control.


Asunto(s)
Malaria , Humanos , India/epidemiología , Malaria/epidemiología , Malaria/prevención & control , Malaria/diagnóstico , Tamizaje Masivo , Prevalencia
9.
Arch Virol ; 157(8): 1441-50, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22552486

RESUMEN

Acinetobacter baumannii infections are difficult to treat due to biofilm formation. The literature shows paucity of data on A. baumannii bacteriophages and their application in biofilm control. In this report, we have isolated a new lytic bacteriophage, AB7-IBB1, infecting A. baumannii. Transmission electron microscopy revealed its resemblance to members of the family Siphoviridae, with a tail size of 240 × 10 nm and an icosahedral head 50 nm in diameter. Plaques were 3-5 mm in diameter after 24 h, increasing to 7-9 mm in three days. The phage genome size was determined to be ~75 kb. AB7-IBB1 could lyse 23 of 39 (59 %) clinical isolates of A. baumannii. It exhibited rapid adsorption (>99 % adsorbed in 5 min), a latency period of 30 min and a burst size of 125 PFU/infected cell. The phage affected A. baumannii biofilm formation on an abiotic surface (polystyrene) and a biotic surface (human embryonic kidney 293 cell line). It also showed biofilm control ability on an abiotic surface (polystyrene). FESEM visualization studies confirmed the detrimental effect of phage AB7-IBB1 on host biofilm. In conclusion, this study reports a novel lytic bacteriophage, AB7-IBB1, belonging to family Siphoviridae, with promising anti-biofilm properties.


Asunto(s)
Acinetobacter baumannii/crecimiento & desarrollo , Acinetobacter baumannii/virología , Biopelículas/crecimiento & desarrollo , Siphoviridae/aislamiento & purificación , Siphoviridae/fisiología , Línea Celular , ADN Viral/genética , Células HEK293 , Especificidad del Huésped , Humanos , Siphoviridae/genética , Proteínas Virales/análisis
10.
Curr Microbiol ; 65(1): 66-72, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22535475

RESUMEN

Biofilm formation in Acinetobacter baumannii is a common cause of nosocomial infections in humans. Clinical devices and abiotic surfaces are important sites of colonization leading to formation of biofilms. Such infections are often resistant to multiple antibiotic therapies, and hence there is need for an effective mode of control. Herein, we describe the isolation, characterization of a new lytic bacteriophage of A. baumannii and its effect on biofilm. The phage AB7-IBB2, with a genome size of about 170 kb was identified to be of family Podoviridae as revealed by transmission electron microscopy. It had an isometric head (35 nm) and a short tail (7 nm). It lysed 19/39 (49 %) clinical isolates of A. baumannii. Rapid adsorption (>99 % adsorbed in 4 min), a latency period of 25 min and a burst size 22 PFU/infected cell was observed. The phage could inhibit A. baumannii biofilm formation and disrupt preformed biofilm as well. The phage has promising potential to be considered as a candidate biocontrol agent for A. baumannii infections.


Asunto(s)
Acinetobacter baumannii/fisiología , Acinetobacter baumannii/virología , Bacteriófagos/aislamiento & purificación , Biopelículas , Podoviridae/aislamiento & purificación , Aguas del Alcantarillado/virología , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/crecimiento & desarrollo , Bacteriófagos/clasificación , Bacteriófagos/genética , Bacteriófagos/ultraestructura , Humanos , Microscopía Electrónica de Transmisión , Podoviridae/clasificación , Podoviridae/genética , Podoviridae/ultraestructura
11.
ScientificWorldJournal ; 2012: 973436, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22593716

RESUMEN

Release of extracellular DNA (eDNA) was observed during in vitro growth of a clinical strain of Acinetobacter baumannii. Membrane vesicles (MV) of varying diameter (20-200 nm) containing DNA were found to be released by transmission electron microscopy (TEM) and atomic force microscopy (AFM). An assessment of the characteristics of the eDNA with respect to size, digestion pattern by DNase I/restriction enzymes, and PCR-sequencing, indicates a high similarity with genomic DNA. Role of eDNA in static biofilm formed on polystyrene surface was evaluated by biofilm augmentation assay using eDNA available in different preparations, for example, whole cell lysate, cell-free supernatant, MV suspension, and purified eDNA. Biofilm augmentation was seen up to 224.64%, whereas biofilm inhibition was 59.41% after DNase I treatment: confirming that eDNA facilitates biofilm formation in A. baumannii. This is the first paper elucidating the characteristics and role of eDNA in A. baumannii biofilm, which may provide new insights into its pathogenesis.


Asunto(s)
Acinetobacter baumannii/genética , Acinetobacter baumannii/fisiología , Biopelículas/crecimiento & desarrollo , ADN Bacteriano/genética , Infecciones por Acinetobacter/microbiología , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Medios de Cultivo Condicionados/metabolismo , Enzimas de Restricción del ADN/metabolismo , ADN Bacteriano/metabolismo , ADN Bacteriano/ultraestructura , Desoxirribonucleasa I/metabolismo , Electroforesis en Gel de Agar , Espacio Extracelular/metabolismo , Humanos , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión
12.
Am J Trop Med Hyg ; 107(4_Suppl): 97-106, 2022 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-36228919

RESUMEN

The Center for the Study of Complex Malaria in India (CSCMi) is one of 10 International Centers of Excellence in Malaria Research funded by the National Institutes of Health since 2010. The Center combines innovative research with capacity building and technology transfer to undertake studies with clinical and translational impact that will move malaria control in India toward the ultimate goal of malaria elimination/eradication. A key element of each research site in the four states of India (Tamil Nadu, Gujarat, Odisha, and Meghalaya) has been undertaking community- and clinic-based epidemiology projects to characterize the burden of malaria in the region. Demographic and clinical data and samples collected during these studies have been used in downstream projects on, for example, the widespread use of mosquito repellants, the population genomics of Plasmodium vivax, and the serological responses to P. vivax and Plasmodium falciparum antigens that reflect past or present exposure. A focus has been studying the pathogenesis of severe malaria caused by P. falciparum through magnetic resonance imaging of cerebral malaria patients. Here we provide a snapshot of some of the basic and applied research the CSCMi has undertaken over the past 12 years and indicate the further research and/or clinical and translational impact these studies have had.


Asunto(s)
Malaria Falciparum , Malaria Vivax , Malaria , Animales , Humanos , India/epidemiología , Malaria/epidemiología , Malaria/prevención & control , Malaria Falciparum/epidemiología , Malaria Falciparum/prevención & control , Malaria Vivax/epidemiología , Plasmodium falciparum/genética , Plasmodium vivax/genética , Investigación Biomédica Traslacional
13.
Life Sci Alliance ; 5(6)2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35260473

RESUMEN

Brain swelling occurs in cerebral malaria (CM) and may either reverse or result in fatal outcome. It is currently unknown how brain swelling in CM reverses, as brain swelling at the acute stage is difficult to study in humans and animal models with reliable induction of reversible edema are not known. In this study, we show that reversible brain swelling in experimental murine CM can be induced reliably after single vaccination with radiation-attenuated sporozoites as proven by in vivo high-field magnetic resonance imaging. Our results provide evidence that brain swelling results from transcellular blood-brain barrier disruption (BBBD), as revealed by electron microscopy. This mechanism enables reversal of brain swelling but does not prevent persistent focal brain damage, evidenced by microhemorrhages, in areas of most severe BBBD. In adult CM patients magnetic resonance imaging demonstrate microhemorrhages in more than one third of patients with reversible edema, emphasizing similarities of the experimental model and human disease. Our data suggest that targeting transcellular BBBD may represent a promising adjunct therapeutic approach to reduce edema and may improve neurological outcome.


Asunto(s)
Edema Encefálico , Malaria Cerebral , Animales , Barrera Hematoencefálica/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/etiología , Edema Encefálico/patología , Edema/patología , Humanos , Malaria Cerebral/patología , Ratones
14.
Am J Trop Med Hyg ; 107(4_Suppl): 90-96, 2022 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-36228922

RESUMEN

The Center for the Study of Complex Malaria in India (CSCMi) was launched in 2010 with the overall goal of addressing major gaps in our understanding of "complex malaria" in India through projects on the epidemiology, transmission, and pathogenesis of the disease. The Center was mandated to adopt an integrated approach to malaria research, including building capacity, developing infrastructure, and nurturing future malaria leaders while conducting relevant and impactful studies to assist India as it moves from control to elimination. Here, we will outline some of the interactions and impacts the Center has had with malaria policy and control counterparts in India, as well as describe emerging needs and new research questions that have become apparent over the past 12 years.


Asunto(s)
Malaria , Humanos , India/epidemiología , Malaria/epidemiología , Malaria/prevención & control
15.
J Exp Med ; 218(3)2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33492344

RESUMEN

Cerebral malaria (CM) is caused by the binding of Plasmodium falciparum-infected erythrocytes (IEs) to the brain microvasculature, leading to inflammation, vessel occlusion, and cerebral swelling. We have previously linked dual intercellular adhesion molecule-1 (ICAM-1)- and endothelial protein C receptor (EPCR)-binding P. falciparum parasites to these symptoms, but the mechanism driving the pathogenesis has not been identified. Here, we used a 3D spheroid model of the blood-brain barrier (BBB) to determine unexpected new features of IEs expressing the dual-receptor binding PfEMP1 parasite proteins. Analysis of multiple parasite lines shows that IEs are taken up by brain endothelial cells in an ICAM-1-dependent manner, resulting in breakdown of the BBB and swelling of the endothelial cells. Via ex vivo analysis of postmortem tissue samples from CM patients, we confirmed the presence of parasites within brain endothelial cells. Importantly, this discovery points to parasite ingress into the brain endothelium as a contributing factor to the pathology of human CM.


Asunto(s)
Barrera Hematoencefálica/patología , Malaria Cerebral/patología , Malaria Cerebral/parasitología , Proteínas Protozoarias/genética , Adulto , Animales , Endocitosis , Células Endoteliales/metabolismo , Células Endoteliales/ultraestructura , Receptor de Proteína C Endotelial/metabolismo , Eritrocitos/parasitología , Eritrocitos/patología , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Microvellosidades/metabolismo , Modelos Biológicos , Simulación del Acoplamiento Molecular , Parásitos/metabolismo , Plasmodium falciparum/aislamiento & purificación , Plasmodium falciparum/ultraestructura , Unión Proteica , Isoformas de Proteínas/metabolismo , Ratas , Esferoides Celulares/metabolismo , Esferoides Celulares/patología
16.
Glob Health Action ; 14(1): 1886458, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33866961

RESUMEN

The Indian state of Odisha has a longstanding battle with forest malaria. Many remote and rural villages have poor access to health care, a problem that is exacerbated during the rainy season when malaria transmission is at its peak. Approximately 62% of the rural population consists of tribal groups who are among the communities most negatively impacted by malaria. To address the persistently high rates of malaria in these remote regions, the Odisha State Malaria Control Program introduced 'malaria camps' in 2017 where teams of health workers visit villages to educate the population, enhance vector control methods, and perform village-wide screening and treatment. Malaria rates declined statewide, particularly in forested areas, following the introduction of the malaria camps, but the impact of the intervention is yet to be externally evaluated. This study protocol describes a cluster-assigned quasi-experimental stepped-wedge study with a pretest-posttest control group design that evaluates if malaria camps reduce the prevalence of malaria, compared to control villages which receive the usual malaria control interventions (e.g. IRS, ITNs), as detected by PCR.


Asunto(s)
Malaria , Humanos , India/epidemiología , Malaria/tratamiento farmacológico , Malaria/epidemiología , Malaria/prevención & control , Reacción en Cadena de la Polimerasa , Prevalencia , Población Rural
17.
JCI Insight ; 6(18)2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34549725

RESUMEN

Cerebral malaria (CM) affects children and adults, but brain swelling is more severe in children. To investigate features associated with brain swelling in malaria, we performed blood profiling and brain MRI in a cohort of pediatric and adult patients with CM in Rourkela, India, and compared them with an African pediatric CM cohort in Malawi. We determined that higher plasma Plasmodium falciparum histidine rich protein 2 (PfHRP2) levels and elevated var transcripts that encode for binding to endothelial protein C receptor (EPCR) were linked to CM at both sites. Machine learning models trained on the African pediatric cohort could classify brain swelling in Indian children CM cases but had weaker performance for adult classification, due to overall lower parasite var transcript levels in this age group and more severe thrombocytopenia in Rourkela adults. Subgrouping of patients with CM revealed higher parasite biomass linked to severe thrombocytopenia and higher Group A-EPCR var transcripts in mild thrombocytopenia. Overall, these findings provide evidence that higher parasite biomass and a subset of Group A-EPCR binding variants are common features in children and adult CM cases, despite age differences in brain swelling.


Asunto(s)
Antígenos de Protozoos/sangre , Edema Encefálico/sangre , Malaria Cerebral/complicaciones , Carga de Parásitos , Proteínas Protozoarias/sangre , Proteínas Protozoarias/genética , Trombocitopenia/sangre , Adolescente , Adulto , Factores de Edad , Anciano , Biomarcadores/sangre , Edema Encefálico/clasificación , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/parasitología , Niño , Preescolar , Receptor de Proteína C Endotelial/metabolismo , Humanos , India , Aprendizaje Automático , Imagen por Resonancia Magnética , Malaui , Persona de Mediana Edad , Gravedad del Paciente , Proteínas Protozoarias/metabolismo , Trombocitopenia/parasitología , Transcripción Genética , Adulto Joven
18.
RSC Adv ; 9(7): 3755-3763, 2019 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35518091

RESUMEN

One-pot condensation of 4-hydroxy coumarins, aldehydes and urea/thiourea to build C-C and C-N bonds is described. Fused pyrimidines have been synthesized under mild reaction conditions using l-proline. The protocol has been performed rapidly and efficiently in water under metal free conditions. Heterocyclic derivatives have been synthesized using the present methodology and avoid the use of hazardous solvents over conventional organic solvents. A proposed mechanism could be established for three component reactions. The present study reveals the first case in which l-proline has been explored as a homogeneous catalyst in the synthesis of fused pyrimidines in water under microwave irradiation. This synthesis involves simple workup and acceptable efficiency. The most notable feature of this protocol is the ability of the catalyst to influence asymmetric induction in the reaction.

19.
EMBO Mol Med ; 11(8): e9903, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31265218

RESUMEN

Malaria is a highly inflammatory disease caused by Plasmodium infection of host erythrocytes. However, the parasite does not induce inflammatory cytokine responses in macrophages in vitro and the source of inflammation in patients remains unclear. Here, we identify oxidative stress, which is common in malaria, as an effective trigger of the inflammatory activation of macrophages. We observed that extracellular reactive oxygen species (ROS) produced by xanthine oxidase (XO), an enzyme upregulated during malaria, induce a strong inflammatory cytokine response in primary human monocyte-derived macrophages. In malaria patients, elevated plasma XO activity correlates with high levels of inflammatory cytokines and with the development of cerebral malaria. We found that incubation of macrophages with plasma from these patients can induce a XO-dependent inflammatory cytokine response, identifying a host factor as a trigger for inflammation in malaria. XO-produced ROS also increase the synthesis of pro-IL-1ß, while the parasite activates caspase-1, providing the two necessary signals for the activation of the NLRP3 inflammasome. We propose that XO-produced ROS are a key factor for the trigger of inflammation during malaria.


Asunto(s)
Inflamación/enzimología , Macrófagos/enzimología , Malaria Cerebral/enzimología , Malaria Falciparum/enzimología , Estrés Oxidativo , Plasmodium falciparum/patogenicidad , Especies Reactivas de Oxígeno/metabolismo , Xantina Oxidasa/metabolismo , Caspasa 1/metabolismo , Células Cultivadas , Citocinas/metabolismo , Interacciones Huésped-Patógeno , Humanos , Inflamación/sangre , Inflamación/parasitología , Mediadores de Inflamación/metabolismo , Activación de Macrófagos , Macrófagos/parasitología , Malaria Cerebral/sangre , Malaria Cerebral/parasitología , Malaria Falciparum/sangre , Malaria Falciparum/parasitología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Transducción de Señal
20.
ACS Omega ; 3(12): 18976-18983, 2018 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31458462

RESUMEN

Sustainable synthesis of Ni-Al double-layered catalysts by the coprecipitation method is described. Synthesized double-layered catalysts have been characterized by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared, and thermogravimetric analyses, which confirmed a hydrotalcite-like structure. In addition, the impact of aging time and temperature on the activity of catalyst has been investigated. Furthermore, it has been confirmed by SEM and TEM analyses that the recovered catalyst has retained its structure. It has also been observed that the prepared material has potency to catalyze the reaction without loss in the yield. To explore the reactivity of the material, the catalyst has been examined in the synthesis of N-(2-hydroxyphenyl)benzamide under solvent-free conditions. The overall process afforded the product with high purity and high yields within short time.

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