35 research outputs found

    Plasmodium falciparum PhIL1-associated complex plays an essential role in merozoite reorientation and invasion of host erythrocytes.

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    The human malaria parasite, Plasmodium falciparum possesses unique gliding machinery referred to as the glideosome that powers its entry into the insect and vertebrate hosts. Several parasite proteins including Photosensitized INA-labelled protein 1 (PhIL1) have been shown to associate with glideosome machinery. Here we describe a novel PhIL1 associated protein complex that co-exists with the glideosome motor complex in the inner membrane complex of the merozoite. Using an experimental genetics approach, we characterized the role(s) of three proteins associated with PhIL1: a glideosome associated protein- PfGAPM2, an IMC structural protein- PfALV5, and an uncharacterized protein-referred here as PfPhIP (PhIL1 Interacting Protein). Parasites lacking PfPhIP or PfGAPM2 were unable to invade host RBCs. Additionally, the downregulation of PfPhIP resulted in significant defects in merozoite segmentation. Furthermore, the PfPhIP and PfGAPM2 depleted parasites showed abrogation of reorientation/gliding. However, initial attachment with host RBCs was not affected in these parasites. Together, the data presented here show that proteins of the PhIL1-associated complex play an important role in the orientation of P. falciparum merozoites following initial attachment, which is crucial for the formation of a tight junction and hence invasion of host erythrocytes

    A Scalable Automated Diagnostic Feature Extraction System for EEGs

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    Researchers using Electroencephalograms (“EEGs”) to diagnose clinical outcomes often run into computational complexity problems. In particular, extracting complex, sometimes nonlinear, features from a large number of time-series often require large amounts of processing time. In this paper we describe a distributed system that leverages modern cloud-based technologies and tools and demonstrate that it can effectively, and efficiently, undertake clinical research. Specifically we compare three types of clusters, showing their relative costs (in both time and money) to develop a distributed machine learning pipeline for predicting gestation time based on features extracted from these EEGs

    A Prospective Study To Evaluate Medical Management Vs Surgical Intervention In Pain Relief And Healing Of Anal Fissure

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    Introduction: Anal fissure is a commonly encountered problem for surgeons. It is a longitudinal tear in distal anal canal with or without an ulcer. It causes significant changes in quality of life. This study was done to compare the efficacy of medical management and surgical intervention in cases of anal fissures. Methods: 50 patients were divided into two groups of 25 each. Group A patients were treated with topical application of 2% diltiazem gel and Group B patients were treated with Lateral sphincterotomy. Both groups were examined weekly for 4 weeks for pain using VAS score and at 12 weeks for healing. Results: 21(84%) patients were pain free after 4 weeks under Group A, 24 (96%) patients were pain free after 4 weeks under Group B. 22(88%) patients were completely healed at 12 weeks under Group A, 25(100%) patients were completely healed at 12 weeks under Group B. Conclusion: Lateral sphincterotomy can be advocated as treatment of choice for anal fissures. It has better pain relief and healing rates compared to topical application of 2% diltiazem gel. Medical Management can be used in patients refusing surgery or unfit for surger

    Comparison of MRI Findings in Diabetic and Nondiabetic Patients with Rhino-Orbito-Cerebral Mucormycosis

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    Objective Rhino-orbito-cerebral mucormycosis (ROCM) has emerged as a key concern during the period of coronavirus disease 2019 (COVID-19) pandemic. Diabetes mellitus is a known risk factor for invasive fungal infection. The aim of this article was to study and compare the radiological features of COVID-19-associated ROCM between diabetic and nondiabetic patients using magnetic resonance imaging. Materials and Methods A retrospective observational study comprising 78 diabetics and 40 nondiabetics who developed ROCM after COVID-19 was conducted. The imaging data of both groups were analyzed, findings tabulated and compared using statistical methods. Results Maxillary and ethmoid sinuses were commonly involved in both groups. Periantral fat and orbits were the most common sites of disease extension. The spread of infection to periantral soft tissue was significantly higher in diabetics (p = 0.049). Diabetics were more likely to have bone, orbit, and brain involvement than nondiabetics, although the difference was not statistically significant. Diabetic patients were the only ones to experience complications such as fungal abscess and cavernous sinus and internal carotid artery involvement. However, a considerable number of nondiabetic patients (22.5%) also had an intracranial extension of disease. Conclusion The radiological appearances and common sites of invasion in ROCM are similar in diabetic and nondiabetic patients. The extensive spread of infection to extra-sinus regions can occur in nondiabetic patients with COVID-19 but is less frequent compared with diabetics

    Imaging of COVID-19-associated rhino-orbital-cerebral mucormycosis: imaging analysis of 120 patients

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    Abstract Background With the ongoing pandemic of COVID-19, there has been a rapid upsurge in cases of rhino-orbital-cerebral mucormycosis (ROCM). It is an opportunistic fungal infection associated with high morbidity and mortality. Rapid and appropriate application of clinical and radiological methods is crucial for early diagnosis, to limit the associated morbidity and improve post-treatment outcomes. In our study, we analyzed imaging features, common sites, and the extent of infection in patients suffering from ROCM. Results The majority of the patients were either diabetics or developed uncontrolled blood glucose levels during COVID-19 infection. 79.17% of patients had a history of treatment with steroid therapy. Headache and facial pain were the most common clinical features seen in 76.67% and 60% of patients, respectively. Maxillary and ethmoid sinuses were commonly involved. The most common extra-sinus site of involvement was periantral fat and orbit, seen in 91 (75.83%) and 84 (70%) patients, respectively. Bone erosion or marrow edema was seen in 72 (60%) patients. Intracranial extension in the form of meningitis, cavernous sinus thrombophlebitis/thrombosis, and brain abscess were seen in 20%, 10%, and 3.3% of patients, respectively. MRI-based staging showed that 24.7% of patients had stage I, 5.83% had stage II, 50% had stage III, and 20% had stage IV disease. Conclusion The spread of COVID-19-associated rhinomucormycosis to extra-sinus sites is common, which can be detected adequately on MRI. The radiological signs of invasion and devitalization of tissues are crucial for the early diagnosis of ROCM

    Isolation, characterization and UPLC-DAD based quantification of antiplasmodial isoquinoline alkaloids from Cissampelos pareira L.

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    C. pareira L. is a centuries-old traditional medicinal plant utilized to treat various diseases like asthma, diarrhea, fever, heart disorders, snakebite, vomiting, malaria, pneumonia, dog bite, inflammation and abdominal pain. Globally, based on traditional knowledge, different parts of this plant are being used individually or in combination in various forms to manage malaria. However, the scientific investigation for validating the most effective part of this plant against malaria parasite has not been done. Therefore, current study aimed to evaluate in vitro antiplasmodial activity of extracts/fractions (whole plant) and decoctions from different parts (roots, stem, leaves and whole plant) of C. pareira against different strains of Plasmodium falciparum followed by antiplasmodial activity guided isolation and quantification of isoquinoline alkaloids in extracts/fractions and decoctions. All extracts/fractions/decoctions and molecules isolated from active fractions were investigated for antiplasmodial activity. Results showed that the chloroform fraction of whole plant was the most promising with IC50 (µg/mL) of 0.79 (Pf3D7) and 2.26 (PfINDO) followed by root decoction having IC50 (µg/mL) 10.22 (Pf3D7) and 7.7 (PfINDO). Among three isolated molecules, two bisbenzylisoquinoline alkaloids namely curine (2) [IC50 (µM) 1.46 (Pf3D7) and 0.51 (PfINDO)], and O,O-dimethylcurine (1) [IC50 (µM) 0.92 (Pf3D7) and 2.6 (PfINDO)], were found to be the most potent against P. falciparum strains. The antiplasmodial activity of chloroform fraction was further validated by the developed UPLC-DAD method, which showed the highest quantities of curine (2) (~107 mg/g) and O,O-dimethylcurine (1) (~15 mg/g) in this fraction. This study showed that the root decoction was more effective than decoctions of each of the other parts of the plant and whole plant hydroalcoholic extract. Further, for the first time, this study validates the traditional use of C. pareira whole plant to manage malaria, providing further opportunity to explore the tremendous structural and chemical diversity of isoquinoline alkaloids for antimalarial drug development

    Identification of Novel, Potent, and Selective Compounds against Malaria Using Glideosomal-Associated Protein 50 as a Drug Target

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    Phylum apicomplexan consists of parasites, such as Plasmodium and Toxoplasma. These obligate intracellular parasites enter host cells via an energy-dependent process using specialized machinery, called the glideosome. In the present study, we used Plasmodium falciparum GAP50, a glideosome-associated protein, as a target to screen 951 different compounds from diverse chemical libraries. Using different screening methods, eight compounds (Hayatinine, Curine, MMV689758 (Bedaquiline), MMV1634402 (Brilacidin), and MMV688271, MMV782353, MMV642550, and USINB4-124-8) were identified, which showed promising binding affinity (KD < 75 μM), along with submicromolar range antiparasitic efficacy and selectivity index > 100 fold for malaria parasite. These eight compounds were effective against Chloroquine-resistant PfINDO and Artemisinin-resistant PfCam3.1R359T strains. Studies on the effect of these compounds at asexual blood stages showed that these eight compounds act differently at different developmental stages, indicating the binding of these compounds to other Plasmodium proteins, in addition to PfGAP50. We further studied the effects of compounds (Bedaquiline and USINB4-124-8) in an in vivo Plasmodium berghei mouse model of malaria. Importantly, the oral delivery of Bedaquiline (50 mg/kg b. wt.) showed substantial suppression of parasitemia, and three out of seven mice were cured of the infection. Thus, our study provides new scaffolds for the development of antimalarials that can act at multiple Plasmodium lifecycle stages

    Identification of Novel, Potent, and Selective Compounds against Malaria Using Glideosomal-Associated Protein 50 as a Drug Target

    No full text
    Phylum apicomplexan consists of parasites, such as Plasmodium and Toxoplasma. These obligate intracellular parasites enter host cells via an energy-dependent process using specialized machinery, called the glideosome. In the present study, we used Plasmodium falciparum GAP50, a glideosome-associated protein, as a target to screen 951 different compounds from diverse chemical libraries. Using different screening methods, eight compounds (Hayatinine, Curine, MMV689758 (Bedaquiline), MMV1634402 (Brilacidin), and MMV688271, MMV782353, MMV642550, and USINB4-124-8) were identified, which showed promising binding affinity (KD < 75 μM), along with submicromolar range antiparasitic efficacy and selectivity index > 100 fold for malaria parasite. These eight compounds were effective against Chloroquine-resistant PfINDO and Artemisinin-resistant PfCam3.1R359T strains. Studies on the effect of these compounds at asexual blood stages showed that these eight compounds act differently at different developmental stages, indicating the binding of these compounds to other Plasmodium proteins, in addition to PfGAP50. We further studied the effects of compounds (Bedaquiline and USINB4-124-8) in an in vivo Plasmodium berghei mouse model of malaria. Importantly, the oral delivery of Bedaquiline (50 mg/kg b. wt.) showed substantial suppression of parasitemia, and three out of seven mice were cured of the infection. Thus, our study provides new scaffolds for the development of antimalarials that can act at multiple Plasmodium lifecycle stages

    Strain-transcending neutralization of malaria parasite by antibodies against Plasmodium falciparum enolase

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    Abstract Background Plasmodium enolase is a target for the growth neutralizing antibodies. Interestingly, the three invasive stages i.e. sporozoites, merozoites, and ookinetes express this protein on their cell surface. Polyclonal anti-Plasmodium falciparum enolase (Pfeno) antibodies disrupt traversal of ookinete through mosquito mid-gut wall as well as have inhibitory effect on parasite growth at erythrocytic stage. In a recent study, it was observed that immunization with a unique epitope of parasite enolase (EWGWS) could confer partial protection against mouse malaria. Further validation is needed for the protective potential of this unique epitope in otherwise highly conserved enolase. Methods In order to investigate the efficacy of growth inhibitory potential of the epitope of P falciparum enolase, a monoclonal antibody specific to EWGWS is generated. In vitro parasite growth inhibition assays and passive immunization of Plasmodium yoelii (or Plasmodium berghei) infected mice were used to assess the parasite growth neutralizing activity of the antibody. Results Screening a panel of monoclonal antibodies raised against recombinant Pfeno that were specific to EWGWS resulted in isolation of H12E1. This antibody recognized only EWGWS epitope containing enolases. H12E1 strongly inhibited parasite growth in culture. This inhibition was strain transcending. Passive infusion of this antibody in P. yoelii or P. berghei infected mice showed significant reduction in parasitemia as compared to controls (p < 0.001). Surface Plasmon Resonance measurements indicated high affinity binding of H12E1 to P. falciparum enolase (KD ~ 7.6 × 10−9M). Conclusions A monoclonal antibody directed against EWGWS epitope of Pfeno was shown to inhibit the growth of blood stage malarial parasites. This inhibition was species/strain transcending and is likely to arise due to blockade of enolase on the surface of merozoites, functionally implicating Pfeno in invasion related events. Presence of enolase on the cell surface of merozoites and ookinetes could potentially result in inhibition of host cell invasions at erythrocytic and transmission stages in the parasite life cycle. It is suggested that antibodies against EWGWS epitope have the potential to confer dual stage, species and strain transcending protection against malaria
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