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1.
J Phys Condens Matter ; 36(21)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38364271

RESUMEN

We report on the magnetic and Hall effect measurements of the magnetic Weyl semimetal, Mn2.94Ge (Ge-rich) single crystal. From the magnetic properties study, we identify unusual multiple magnetic transitions below the Ne'el temperature of 353 K, such as the spin-reorientation (TSR) and ferromagnetic-like transitions. Consistent with the magnetic properties, the Hall effect study shows unusual behavior around the spin-reorientation transition. Specifically, the anomalous Hall conductivity increases with increasing temperature, reaching a maximum atTSR, which then gradually decreases with increasing temperature. This observation is quite in contrast to the Mn3+δGe (Mn-rich) system, though both compositions share the same hexagonal crystal symmetry. This study unravels the sensitivity of magnetic and topological properties on the Mn concentration.

2.
J Phys Condens Matter ; 36(12)2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38056011

RESUMEN

Using angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT) calculations, we systematically studied the electronic band structure of Mn3Ge in the vicinity of the Fermi level. We observe several bands crossing the Fermi level, confirming the metallic nature of the studied system. We further observe several flat bands along various high symmetry directions, consistent with the DFT calculations. The calculated partial density of states suggests a dominant Mn 3dorbital contribution to the total valence band DOS. With the help of orbital-resolved band structure calculations, we qualitatively identify the orbital information of the experimentally obtained band dispersions. Out-of-plane electronic band dispersions are explored by measuring the ARPES data at various photon energies. Importantly, our study suggests relatively weaker electronic correlations in Mn3Ge compared to Mn3Sn.

3.
PLoS Negl Trop Dis ; 17(11): e0011702, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37939204

RESUMEN

BACKGROUND: Aedes-borne disease risk is associated with contemporary urbanization practices where city developing structures function as a catalyst for creating mosquito breeding habitats. We lack better understanding on how the links between landscape ecology and urban geography contribute to the prevalence and abundance of mosquito and pathogen spread. METHODS: An outdoor longitudinal study in Bengaluru (Karnataka, India) was conducted between February 2021 and June 2022 to examine the effects of macrohabitat types on the diversity and distribution of larval habitats, mosquito species composition, and body size to quantify the risk of dengue outbreak in the landscape context. FINDINGS: A total of 8,717 container breeding sites were inspected, of these 1,316 were wet breeding habitats. A total of 1,619 mosquito larvae representing 16 species from six macrohabitats and nine microhabitats were collected. Aedes aegypti and Aedes albopictus were the dominant species and significantly higher in artificial habitats than in natural habitats. Breeding preference ratio for Aedes species was high in grinding stones and storage containers. The Aedes infestation indices were higher than the WHO threshold and showed significant linear increase from Barren habitat to High density areas. We found Ae. albopictus breeding in sympatry with Ae. aegypti had shorter wing length. CONCLUSIONS: A large proportion of larval habitats were man-made artificial containers. Landscape ecology drives mosquito diversity and abundance even at a small spatial scale which could be affecting the localized outbreaks. Our findings showed that sampling strategies for mosquito surveillance must include urban environments with non-residential locations and dengue transmission reduction programmes should focus on 'neighbourhood surveillance' as well to prevent and control the rising threat of Aedes-borne diseases.


Asunto(s)
Aedes , Dengue , Humanos , Animales , Dengue/epidemiología , Larva , Estudios Longitudinales , India/epidemiología , Ecosistema , Mosquitos Vectores
4.
Heliyon ; 9(10): e20870, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37867895

RESUMEN

Water splitting using an electrochemical device to produce hydrogen fuel is a green and economic approach to solve the energy and environmental crisis. The realistic design of durable electro-catalysts and their synthesis using a simplistic technique is a great challenge to produce hydrogen by water electrolysis. Herein, we report a stable highly active barium ruthenium oxide (BRO) electro-catalysts over Ti plate using a soft chemical method at low temperature. The synthesized material shows facile hydrogen evolution reaction (HER) as well as oxygen evolution reaction (OER) in alkaline medium with over-potentials of 195 mV and 300 mV, respectively at a current density of 10 mA cm-2. The excellent stability lasts for at least 24 h without any degradation for both the HER and OER at the current density of 10 mA cm-2, inferring the practical applications of the material toward production of green hydrogen energy. Certainly, the synthesized catalyst is capable adequately for the overall water splitting at a cell voltage of 1.60 V at a current density of 10 mA cm-2 with an impressive stability for at least 24 h, showing a minimum loss of potential. Thus the present work contributes to the rational design of stable and efficient electro-catalysts for overall water splitting reaction in alkaline media.

5.
J Phys Condens Matter ; 35(48)2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37604158

RESUMEN

We report on the tuning of electrical, magnetic, and topological properties of the magnetic Weyl semimetal (Mn3+xGe) by Fe doping at the Mn site, Mn(3+x)-δFeδGe (δ= 0, 0.30, and 0.62). Fe doping significantly changes the electrical and magnetic properties of Mn3+xGe. The resistivity of the parent compound displays metallic behavior, the system withδ= 0.30 of Fe doping exhibits semiconducting or bad-metallic behavior, and the system withδ= 0.62 of Fe doping demonstrates a metal-insulator transition at around 100 K. Further, we observe that the Fe doping increases in-plane ferromagnetism, magnetocrystalline anisotropy, and induces a spin-glass state at low temperatures. Surprisingly, topological Hall state has been noticed at a Fe doping ofδ= 0.30 that is not found in the parent compound or withδ= 0.62 of Fe doping. In addition, spontaneous anomalous Hall effect observed in the parent system is significantly reduced with increasing Fe doping concentration.

6.
J Infect Dev Ctries ; 17(5): 725-731, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-37279422

RESUMEN

Hyperparasitaemia is an important event in the cascade of Plasmodium falciparum severe malaria (SM), and may also lead to SM associated complications and death, if left untreated. Here, we report two hyperparasitaemic patients with no life-threatening complications. Malaria diagnosis was performed using thick and thin blood smears and immunochromatographic-based rapid diagnostic tests (RDTs) purchased from three different manufacturers. Parasitaemia was calculated following the World Health Organization (WHO) guidelines. Haematological and biochemical investigations were also performed. Weekly follow-up of blood smear examination, blood pressure and temperature were recorded up to day 63. The first patient had 42% parasitaemia (100% asexual parasites). The second patient had 9.5% parasitaemia, comprising 46% asexual and 54% sexual stages, with a 1:1 male to female ratio. On the day of admission, both had presented abnormal haematological and biochemical parameters compared to the reference values. Remarkably, both the patients recovered successfully with oral artemisinin-based combination therapy (ACT) and a single dose of primaquine on day 1. Weekly follow-up did not show any parasite suggesting successful treatment with ACT without any side effects. The presence of hypergametocytaemia may hinder malaria elimination efforts, if not treated immediately.


Asunto(s)
Antimaláricos , Artemisininas , Malaria Falciparum , Malaria , Humanos , Masculino , Femenino , Plasmodium falciparum , Antimaláricos/uso terapéutico , Antimaláricos/farmacología , Malaria Falciparum/diagnóstico , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/parasitología , Malaria/tratamiento farmacológico , Parasitemia/diagnóstico , Parasitemia/tratamiento farmacológico , Artemisininas/uso terapéutico , Artemisininas/farmacología
7.
Pathog Glob Health ; 116(8): 463-464, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35818754

RESUMEN

Malaria and malnutrition are major public health problems in India, especially in the rural and tribal communities, and also remain primary causes of morbidity and mortality among children younger than five years. Both diseases are synergistic with each other. It is essential to have a better understanding of the intricate relationships between malnutrition and malaria to target interventions in areas where both diseases coexist. This article highlights the synergistic relationship between malnutrition and malaria, and how malnutrition and malaria play a significant role in disease severity and eventually hinder the elimination of these diseases by 2030. The government and several private sectors have made a substantial dent through various programmes and schemes. However, supplementing nutrition-sensitive measures, including easy accessibility to a healthy balanced diet, safe drinking water and improved sanitation, is necessary. Therefore, if India really aims to achieve its dream of disease elimination (malaria and all forms of malnutrition) by 2030, it is imperative that tribal regions are given more attention and all possible strategies are applied in the country's remotest corners.


Asunto(s)
Malaria , Desnutrición , Niño , Humanos , Desnutrición/epidemiología , Estado Nutricional , Malaria/epidemiología , Malaria/prevención & control , Saneamiento , Erradicación de la Enfermedad , India/epidemiología
8.
OMICS ; 26(4): 179-188, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35404686

RESUMEN

Coronavirus disease 2019 (COVID-19) is a systemic disease, impacting multiple organs in the human body. But COVID-19 also impacts other diseases of relevance to public and planetary health. To understand and respond to the COVID-19 pandemic, we need an intersectional conceptual lens and systems thinking. For example, the strain on health care systems due to COVID-19 has adversely impacted global malaria elimination programs. With many epidemiological, clinical, and biological parallels documented, we examined in this study the scenario of malaria and COVID-19 syndemic in India. The disruptive influence of COVID-19 on the National Framework for Malaria Elimination (NFME), impact of unintended chemoprophylaxis, population genetic influences, and the shifting patterns of epidemiology are compared. Importantly, a time series analysis forecasted the burden of malaria increasing in the upcoming years. Although reported malaria cases showed a decline in 2020 compared to the previous years, an increase in cases was documented in 2021, with nine states reporting an increase up to July 2021. Pandemics often cause crosscutting disruptions in health care. Reshaping the priorities of the malaria elimination program and a diligent implementation of the priorities in the NFME would, therefore, be well-advised: (1) vector control, (2) antimalarial therapy recommendations, (3) monitoring drug resistance, (4) prevention of the spread of asymptomatic disease-causing low-density transmission, and (5) large-scale testing measures. In conclusion, the findings from the present study inform future comparative studies in other world regions to better understand the broader, systemic, temporal, and spatial impacts of the COVID-19 pandemic on existing and future diseases across public health systems and services.


Asunto(s)
Antimaláricos , COVID-19 , Malaria , Antimaláricos/uso terapéutico , COVID-19/epidemiología , Humanos , Malaria/epidemiología , Malaria/prevención & control , Pandemias/prevención & control , Vigilancia de la Población
9.
Sci Rep ; 12(1): 3610, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-35246568

RESUMEN

Anopheles stephensi is the most menacing malaria vector to watch for in newly urbanising parts of the world. Its fitness is reported to be a direct consequence of the vector adapting to laying eggs in over-head water tanks with street-side water puddles polluted by oil and sewage. Large frequent inversions in the genome of malaria vectors are implicated in adaptation. We report the genome assembly of a strain of An. stephensi of the type-form, collected from a construction site from Chennai (IndCh) in 2016. The genome reported here with a L50 of 4, completes the trilogy of high-resolution genomes of strains with respect to a 16.5 Mbp 2Rb genotype in An. stephensi known to be associated with adaptation to environmental heterogeneity. Unlike the reported genomes of two other strains, STE2 (2R+b/2Rb) and UCI (2Rb/2Rb), IndCh is found to be homozygous for the standard form (2R+b/2R+b). Comparative genome analysis revealed base-level details of the breakpoints and allowed extraction of 22,650 segregating SNPs for typing this inversion in populations. Whole genome sequencing of 82 individual mosquitoes from diverse geographical locations reveal that one third of both wild and laboratory populations maintain the heterozygous genotype of 2Rb. The large number of SNPs can be tailored to 1740 exonic SNPs enabling genotyping directly from transcriptome sequencing. The genome trilogy approach accelerated the study of fine structure and typing of an important inversion in An. stephensi, putting the genome resources for this understudied species on par with the extensively studied malaria vector, Anopheles gambiae. We argue that the IndCh genome is relevant for field translation work compared to those reported earlier by showing that individuals from diverse geographical locations cluster with IndCh, pointing to significant convergence resulting from travel and commerce between cities, perhaps, contributing to the survival of the fittest strain.


Asunto(s)
Anopheles , Malaria , Animales , Anopheles/genética , Inversión Cromosómica , India , Mosquitos Vectores/genética , Agua
10.
IEEE Trans Med Imaging ; 41(4): 815-825, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34699354

RESUMEN

Despite the promise of Convolutional neural network (CNN) based classification models for histopathological images, it is infeasible to quantify its uncertainties. Moreover, CNNs may suffer from overfitting when the data is biased. We show that Bayesian-CNN can overcome these limitations by regularizing automatically and by quantifying the uncertainty. We have developed a novel technique to utilize the uncertainties provided by the Bayesian-CNN that significantly improves the performance on a large fraction of the test data (about 6% improvement in accuracy on 77% of test data). Further, we provide a novel explanation for the uncertainty by projecting the data into a low dimensional space through a nonlinear dimensionality reduction technique. This dimensionality reduction enables interpretation of the test data through visualization and reveals the structure of the data in a low dimensional feature space. We show that the Bayesian-CNN can perform much better than the state-of-the-art transfer learning CNN (TL-CNN) by reducing the false negative and false positive by 11% and 7.7% respectively for the present data set. It achieves this performance with only 1.86 million parameters as compared to 134.33 million for TL-CNN. Besides, we modify the Bayesian-CNN by introducing a stochastic adaptive activation function. The modified Bayesian-CNN performs slightly better than Bayesian-CNN on all performance metrics and significantly reduces the number of false negatives and false positives (3% reduction for both). We also show that these results are statistically significant by performing McNemar's statistical significance test. This work shows the advantages of Bayesian-CNN against the state-of-the-art, explains and utilizes the uncertainties for histopathological images. It should find applications in various medical image classifications.


Asunto(s)
Mama , Redes Neurales de la Computación , Teorema de Bayes , Mama/diagnóstico por imagen , Incertidumbre
11.
Asian J Transfus Sci ; 15(2): 133-139, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34908743

RESUMEN

BACKGROUND: Significant blood loss and requirement of allogenic blood transfusion during or after total knee replacement (TKR) have been reported. Incidence of blood transfusion in TKR is highly variable and depends on several factors. We investigated the blood utilization in patients undergoing TKR in our hospital and depicted the important risk factors that determine the need of allogenic blood transfusion in primary unilateral TKR. MATERIALS AND METHODS: The study included 1241 consecutive patients undergoing primary unilateral total knee arthroplasty. All the surgeries were performed by a single surgical team of orthopedists following standard procedure. Patient and disease details were obtained from patient file and hospital information system. Compatibility test was performed in blood bank before blood reservation following mandatory guidelines. Details of test, blood issue, and blood transfusion were documented in the blood bank. RESULTS: Of 1241 enrolled patients, 1069 (86.2%) were female. The median age of patients was 66 years with mean preoperative hemoglobin of 9.9 g/dL. Allogenic blood transfused was needed in 223 (17.9%) patients. Diabetes mellitus, hypertension, thyroid disorders, and chronic heart diseases were the major comorbid conditions. Risk factors such as gender, American Society of Anesthesiologists score, preoperative hemoglobin, and intraoperative and postoperative blood losses were significantly associated with blood transfusion. CONCLUSION: The risk factors determining blood transfusion in TKR vary between studies, however, all centers should establish standard operating procedures describing the surgical procedure and transfusion support in TKR. In addition, each center may develop specific blood management strategy to rationalize blood transfusion in TKR and overall successful care in TKR.

12.
Malar J ; 20(1): 139, 2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-33685454

RESUMEN

BACKGROUND: Malaria control system (MCS), an Information technology (IT)-driven surveillance and monitoring intervention is being adopted for elimination of malaria in Mangaluru city, Karnataka, India since October 2015. This has facilitated 'smart surveillance' followed by required field response within a timeline. The system facilitated data collection of individual case, data driven mapping and strategies for malaria elimination programme. This paper aims to present the analysis of post-digitization data of 5 years, discuss the current operational functionalities of MCS and its impact on the malaria incidence. METHODS: IT system developed for robust malaria surveillance and field response is being continued in the sixth year. Protocol for surveillance control was followed as per the national programme guidelines mentioned in an earlier publication. Secondary data from the malaria control system was collated and analysed. Incidence of malaria, active surveillance, malariogenic conditions and its management, malariometric indices, shrinking malaria maps were also analysed. RESULTS: Smart surveillance and subsequent response for control was sustained and performance improved in five years with participation of all stakeholders. Overall malaria incidence significantly reduced by 83% at the end of 5 years when compared with year of digitization (DY) (p < 0.001). Early reporting of new cases (within 48 h) was near total followed by complete treatment and vector control. Slide positivity rate (SPR) decreased from 10.36 (DY) to 6.5 (PDY 5). Annual parasite incidence (API) decreased from 16.17 (DY) to 2.64 (PDY 5). There was a negative correlation between contact smears and incidence of malaria. Five-year data analyses indicated declining trends in overall malaria incidence and correlation between closures by 14 days. The best impact on reduction in incidence of malaria was recorded in the pre-monsoon months (~ 85%) compared to lower impact in July-August months (~ 40%). CONCLUSION: MCS helped to micromanage control activities, such as robust reporting, incidence-centric active surveillance, early and complete treatment, documentation of full treatment of each malaria patient, targeted mosquito control measures in houses surrounding reported cases. The learnings and analytical output from the data helped to modify strategies for control of both disease and the vector, heralding the city into the elimination stage.


Asunto(s)
Manejo de Datos/estadística & datos numéricos , Erradicación de la Enfermedad/métodos , Tecnología de la Información/estadística & datos numéricos , Malaria/epidemiología , Malaria/prevención & control , Vigilancia de la Población/métodos , Erradicación de la Enfermedad/instrumentación , Humanos , India/epidemiología , Estaciones del Año
13.
J Parasit Dis ; 45(1): 176-190, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33100734

RESUMEN

Merozoite surface protein-1 (MSP-1) of malaria parasites has been extensively studied as a malaria vaccine candidate and the antibody response to this protein is an important indicator of protective immunity to malaria. Mangaluru city and its surrounding areas in southwestern India are endemic to malaria with Plasmodium vivax being the most widespread and prevalent species although P. falciparum also frequently infects. However, no information is available on the level of protective immunity in this population. In this regard, a prospective hospital-based study was performed in malarial patients to assess antibody responses against the 19-kDa C-terminal portion of P. vivax and P. falciparum MSP-1 (MSP-119). Serum samples from 51 healthy endemic controls and 267 infected individuals were collected and anti-MSP-119 antibody levels were analyzed by ELISA. The possible association between the antibody responses and morbidity parameters such as malarial anemia and thrombocytopenia was investigated. Among the 267 infected cases, 144 had P. vivax and 123 had P. falciparum infections. Significant levels of anti-MSP-119 antibody were observed both in P. vivax (123/144; 85.4%) and P. falciparum (108/123; 87.9%) infected individuals. In both type of infections, the major antibody isotypes were IgG1 and IgG3. The IgG levels were found to be increased in patients with severe anemia and thrombocytopenia. The antibody levels were also higher in infected individuals who had several previous infections, although antibodies produced during previous infections were short lived. The predominance of cytophilic anti-MSP-119 IgG1 and IgG3 antibodies suggests the possibility of a dual role of Pv MSP-119 and Pf MSP-119 during malarial immunity and pathogenesis.

14.
Mol Biol Rep ; 47(11): 8841-8848, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33113080

RESUMEN

Severe malaria (SM) caused by Plasmodium falciparum (Pf) infection has been associated with life-threatening anemia, metabolic acidosis, cerebral malaria and multiorgan dysfunction. It may lead to death if not treated promptly. RNASE 3 has been linked to Pf growth inhibition and its polymorphisms found associated with SM and cerebral malaria in African populations. This study aimed to assess the association of RNASE 3 polymorphisms with SM in an Indian population. RNASE 3 gene and flanking regions were amplified followed by direct DNA sequencing in 151 Indian patients who visited Wenlock District Government Hospital, Mangalore, Karnataka, India. Allele, genotype and haplotype frequencies were compared between patients with SM (n = 47) and uncomplicated malaria (UM; n = 104). Homozygous mutant genotype was only found for rs2233860 (+ 499G > C) polymorphism (< 1% frequency). No significant genetic associations were found for RNASE 3 polymorphism genotypes and alleles in Indian SM patients using the Fisher's exact test. C-G-G haplotype of rs2233859 (- 38C > A), rs2073342 (+ 371C > G) and rs2233860 (+ 499G > C) polymorphisms was correlated significantly with SM patients (OR = 3.03; p = 0.008) after Bonferroni correction. A haplotype of RNASE 3 gene was found associated with an increased risk of SM and confirming that RNASE 3 gene plays a role in susceptibility to SM.


Asunto(s)
Proteína Catiónica del Eosinófilo/genética , Predisposición Genética a la Enfermedad/genética , Haplotipos , Malaria Falciparum/genética , Polimorfismo de Nucleótido Simple , Adolescente , Adulto , Alelos , Niño , Proteína Catiónica del Eosinófilo/metabolismo , Femenino , Frecuencia de los Genes , Genotipo , Humanos , India , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Índice de Severidad de la Enfermedad , Adulto Joven
15.
Dalton Trans ; 49(36): 12716-12730, 2020 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-32959828

RESUMEN

A new type of mesoporous silica (MS) with high surface area and large pore volume has been synthesised by employing a rapid sol-gel based inverse micelle method and electrochemically active metal center, manganese, has been incorporated into it. The MnO2 decorated silica composites are obtained through the wet impregnation technique using KMnO4 followed by their reduction under neutral conditions. The structure and surface area of the samples have been characterised by powder X-ray diffraction (XRD), BET surface area and pore size analysis, transmission and scanning electron microscopy (TEM and FE-SEM), FT-IR spectroscopy and X-ray photoelectron spectroscopy (XPS). Electrochemical techniques, i.e. cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS), have been used to evaluate the electrochemical properties of the composites. The resultant composite MS/MnO2-3 with a significantly high surface area (453 m2 g-1) is found to exhibit a superior specific capacitance of 1158.50 F g-1 at a scan rate of 5 mV s-1 which is very close to the theoretical value and retains 87.8% of its capacitance up to 1000 cycles at 1 A g-1 current density. The outstanding electrochemical performance of the composite can be attributed to the high surface area and uniform pore size distribution of the novel silica host which simultaneously increases the electrochemically active centres, promotes electrolyte penetration and enhances electron transport. The simplicity of the synthesis process developed here is interesting for wide-scale production of MnO2-based electro-active materials.

16.
Malar J ; 19(1): 214, 2020 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-32571333

RESUMEN

BACKGROUND: Vivax malaria is associated with significant morbidity and economic loss, and constitutes the bulk of malaria cases in large parts of Asia and South America as well as recent case reports in Africa. The widespread prevalence of vivax is a challenge to global malaria elimination programmes. Vivax malaria control is particularly challenged by existence of dormant liver stage forms that are difficult to treat and are responsible for multiple relapses, growing drug resistance to the asexual blood stages and host-genetic factors that preclude use of specific drugs like primaquine capable of targeting Plasmodium vivax liver stages. Despite an obligatory liver-stage in the Plasmodium life cycle, both the difficulty in obtaining P. vivax sporozoites and the limited availability of robust host cell models permissive to P. vivax infection are responsible for the limited knowledge of hypnozoite formation biology and relapse mechanisms, as well as the limited capability to do drug screening. Although India accounts for about half of vivax malaria cases world-wide, very little is known about the vivax liver stage forms in the context of Indian clinical isolates. METHODS: To address this, methods were established to obtain infective P. vivax sporozoites from an endemic region in India and multiple assay platforms set up to detect and characterize vivax liver stage forms. Different hepatoma cell lines, including the widely used HCO4 cells, primary human hepatocytes as well as hepatocytes obtained from iPSC's generated from vivax patients and healthy donors were tested for infectivity with P. vivax sporozoites. RESULTS: Both large and small forms of vivax liver stage are detected in these assays, although the infectivity obtained in these platforms are low. CONCLUSIONS: This study provides a proof of concept for detecting liver stage P. vivax and provide the first characterization of P. vivax liver stage forms from an endemic region in India.


Asunto(s)
Estadios del Ciclo de Vida , Hígado/parasitología , Malaria Vivax/parasitología , Plasmodium vivax/crecimiento & desarrollo , India , Plasmodium vivax/aislamiento & purificación
17.
J Vector Borne Dis ; 57(3): 213-220, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-34472504

RESUMEN

BACKGROUND & OBJECTIVES: In India, the burden of Plasmodium vivax malaria has been projected to be highest in some areas. This study investigated the efficacy and safety of fixed dose combination (FDC) of arterolane maleate (AM) 37.5 mg and piperaquine phosphate 187.5 mg (PQP) dispersible tablets and (not with) chloroquine in the treatment of uncomplicated vivax malaria in pediatric patients. METHODS: This multicentric, open-label trial was carried out at 12 sites in India. A total of 164 patients aged 6 months to 12 years with P. vivax malaria were randomized in a ratio of 2:1 to AM-PQP (111 patients) or chloroquine (53 patients) arms. The duration of follow up was 42 days. RESULTS: At 72 hours, the proportion of a parasitaemic and afebrile patients was 100% in both treatment arms in per protocol (PP) population, and 98.2% and 100% [95% CI: -1.8 (-6.33 to 5.08)] in AM-PQP and chloroquine arms, respectively, in intent to treat (ITT) population. The efficacy and safety of AM-PQP was found to be comparable to chloroquine in the treatment of uncomplicated P. vivax malaria in pediatric patients. Overall, the cure rate at Day 28 and 42 was >95% for both AM-PQP or CQ. The commonly reported clinical adverse event was vomiting. No patient was discontinued for any QTc abnormality. INTERPRETATION & CONCLUSION: The efficacy and safety of FDC of arterolane maleate and piperaquine phosphate was found to be comparable to chloroquine for treatment of uncomplicated P. vivax malaria in pediatric patients.


Asunto(s)
Antimaláricos , Malaria Falciparum , Malaria Vivax , Antimaláricos/efectos adversos , Niño , Cloroquina/efectos adversos , Cloroquina/análogos & derivados , Compuestos Heterocíclicos con 1 Anillo , Humanos , Malaria Falciparum/tratamiento farmacológico , Malaria Vivax/tratamiento farmacológico , Maleatos/uso terapéutico , Peróxidos , Fosfatos/uso terapéutico , Plasmodium vivax , Quinolinas , Compuestos de Espiro
18.
Parasitol Res ; 119(3): 1043-1056, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31754856

RESUMEN

The aim of this study was to assess the clinical profile, severity and complications of patients suffering from malaria in Mangaluru, a southwestern coastal city in India. A total of 579 patients, who were treated at the District Wenlock Hospital, Mangaluru, and 168 healthy controls were recruited in this study. The clinical profile, haematological and biochemical parameters, and disease complications were assessed. The majority of patients were treated as outpatients and patients who had severe clinical conditions were admitted to the hospital for treatment and supportive care. Among the total 579 patients recruited in this study, the distribution of P. vivax, P. falciparum and mixed infections were 364 (62.9%), 150 (25.9%) and 65 (11.2%), respectively. Among these, 506 (87.4%) had mild malaria, whereas 73 (12.6%) had severe malaria. Overall, the clinical features and severity of malaria in P. vivax and mixed infection patients were comparable to P. falciparum patients, albeit with some significant differences. The clinical complications in severe malaria cases included thrombocytopenia (50.7%), metabolic acidosis (30.1%), severe anaemia (26.0%), jaundice (21.9%), hepatic dysfunction (15.1%), acute renal failure (6.8%), haematuria (8.2%), hypotension (9.6%), cerebral malaria (1.4%) and acute respiratory distress syndrome (1.4%). All the patients with severe malaria recruited in our study were successfully treated and discharged. Majority of patients had mild malaria, likely due to seeking treatment soon after experiencing symptoms and/or having preexisting immune protection. However, a significant number of patients had severe malaria and required hospital admission indicating that there is a substantial need for creating awareness among vulnerable immigrant population. Implementing effective surveillance and vector control measures in malaria hotspot locations in the city and educating people about preventive measures are likely to reduce the malaria burden in this endemic region.


Asunto(s)
Malaria/sangre , Malaria/patología , Adulto , Coinfección/sangre , Coinfección/epidemiología , Coinfección/parasitología , Coinfección/patología , Femenino , Humanos , India/epidemiología , Malaria/epidemiología , Malaria/parasitología , Masculino , Persona de Mediana Edad , Plasmodium falciparum/aislamiento & purificación , Plasmodium vivax/aislamiento & purificación
19.
Malar J ; 18(1): 444, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31878929

RESUMEN

BACKGROUND: Under-reporting, delayed diagnosis, incomplete treatment and inadequate vector management are few among many factors responsible for uninterrupted transmission of malaria in India. Information technology (IT) and mobile apps can be utilized effectively to overcome these hurdles. Indigenously developed digital handheld geographic information system (GIS)-tagged Android-based tablets (TABs) has been designed especially for implementation of digitization protocol. This has changed the effectiveness of malaria surveillance and intervention strategies in a malaria endemic area of Mangaluru city, Karnataka, India. METHODS: A software was developed and implemented for control measures to create a digital database of each malaria case. Secondary data analyses were carried out to determine and compare differences in malariometric indices between pre- and post-digitization years. With the introduction of this software active surveillance, information education and communication (IEC), and anti-vector measures were made 'incidence-centric'. This means that the entire control measures were carried out in the houses where the malaria cases (index cases) were reported and also in surrounding houses. RESULTS: Annual blood examination rate (ABER) increased from 13.82 to 32.8%. Prompt reporting of new cases had improved (36% within 24 h and 80% within 72 h). Complete treatment and parasite clearance time were documented in 98% of cases. In the second post-digitization year untraceable cases reduced from 11.3 to 2.7%; contact blood smears collection also increased significantly (p < 0.001); Slide Positivity Rate (SPR) decreased from 15.5 to 10.48%; malaria cases reduced by 30%. CONCLUSIONS: IT is very useful in translation of digitized surveillance to core interventions thereby effectively reduce incidence of malaria. This technology can be used effectively to translate smart surveillance to core interventions following the '1-3-7-14' strategy.


Asunto(s)
Computadoras de Mano/estadística & datos numéricos , Erradicación de la Enfermedad/instrumentación , Sistemas de Información Geográfica , Malaria/prevención & control , Vigilancia de la Población/métodos , Humanos , India
20.
Trop Parasitol ; 9(2): 98-107, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31579664

RESUMEN

BACKGROUND AND OBJECTIVES: Dysregulated production of inflammatory cytokines might play important role in anemia during malaria infection. The objective of this study was to assess the extent of anemia due to malaria, associated complications, and inflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin [IL]-6, and IL-10) across varying anemic intensity during malaria infections. MATERIALS AND METHODS: A hospital-based cross-sectional study was conducted at District Wenlock hospital in Mangaluru city. Samples from 627 patients and 168 healthy controls (HC) were analyzed for level of hemoglobin (Hb), red blood cells (RBCs), and inflammatory cytokines. The blood cell parameters and inflammatory cytokines levels across varying intensity of anemia were analyzed using Kruskal-Wallis test and pair-wise comparison between two groups were by Mann-Whitney U-test. Correlations were calculated by Pearson's and Spearman rank correlations. RESULTS: Compared to HC, Hb, and RBC levels were significantly lower in infected patients. On comparison with mild anemia patients (Hb 8-10.9 g/dL), the levels of TNF-α and IL-6 were significantly elevated, whereas IL-10 levels were lower during severe anemia (SA) (Hb <5 g/dL). In this endemic setting, we found a strong negative association between Hb levels and parasitemia, Hb and TNF-α, and positive relationship with IL-10; anemic patients also had significantly high TNF-α/IL-10 ratios. SA was associated with complications such as acute renal failure (16.0%), jaundice (16.0%), metabolic acidosis (24.0%), hypoglycemia (12.0%), hyperparasitemia (4.0%), and hepatic dysfunction (16.0%). CONCLUSIONS: Contrary to its benign reputation, Plasmodium vivax (Pv) infections can also result in severe malarial anemia (SMA) and its associated severe complications similar to Plasmodium falciparum infections. Dysregulated inflammatory cytokine responses play an important role in the pathogenesis of SMA, especially during Pv infections.

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