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1.
Int J Crit Illn Inj Sci ; 14(1): 9-14, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38715748

RESUMEN

Background: This study was done to compare single stage percutaneous dilation tracheostomy (PDT) and open surgical tracheostomy (ST) in critically ill patients. Methods: A randomized controlled study was conducted on 60 critically ill patients admitted in the intensive care unit (ICU). The patients were randomized into ST or PDT group with 30 in each group. The duration of procedure and associated perioperative/postoperative complications were noted and compared. Results: A total of 60 critically ill patients were included with 30 each in both groups. Compared to ST, PDT had significantly lesser mean duration of procedure (5 ± 1.64 vs. 21.33 ± 4.77 min, P < 0.0001) and comparable incidence of complications (3.33% vs. 20%, P = 0.103), which included 5-10 ml of bleeding (0% vs. 13.33%), cardiac arrest (0% vs. 3.33%), atrial fibrillation (3.33% vs. 0%), and tracheoesophageal fistula (0% vs. 3.33%). Conclusion: PDT performed in the ICU is a quick, safe, and reliable procedure with comparable complications to ST.

2.
Indian Heart J ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38574813

RESUMEN

BACKGROUND: Despite significant progress in primary prevention, rates of myocardial infarction (MI) in South Asian population is alarmingly high. OBJECTIVES: We sought to compare risk factor profiles and outcomes between individuals with ST-Segment Elevation Myocardial Infarction (STEMI) in young (<50 years) and old (≥50 years) age groups. METHODS: North India STEMI Registry (NORIN-STEMI) is a prospective observational registry of patients hospitalised with STEMI. We conducted a study of young patients (<50 years) regarding their risk factors for coronary artery disease (CAD), in-hospital and 30-day mortality and compared with their older counterpart. RESULTS: Among 5335 patients enrolled, 1752 (32.8%) were young and were 19 years younger than the older cohort. Major risk factors in young patients were physical inactivity (75.1%) and alcohol intake (67.8%). Higher prevalence of tobacco use (66.6% vs 52.4%), but lower prevalence of diabetes (16% vs 26.3%) and hypertension (18.5% vs 29.9%) were seen in young STEMI. Young patients were less likely to die both in-hospital (5.9% vs 10.0%) and at 30-days (11.1% vs 16.2%). Left ventricular ejection fraction (LVEF) < 30% at admission [OR: 8.00, 95% confidence interval (CI): 4.60-13.90, P < 0.001 in-hospital, OR: 3.92, 95% CI: 2.69-5.73 at 30-days] and female sex were strongest predictors of mortality. CONCLUSIONS: Young STEMI patients constituted one-third of total cohort. Most of them were tobacco consumers with lesser prevalence of diabetes and hypertension. They were less likely to die both in-hospital and at 30 days because of earlier presentation to a health care facility and hence a relatively preserved LVEF.

3.
Indian J Nephrol ; 34(2): 191-194, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38681007

RESUMEN

Posttransplant thrombotic microangiopathy (PT-TMA) can be caused by calcineurin inhibitors (CNIs), ischemic injury, infections, or antibody-mediated rejection (ABMR). Delayed recognition can result in allograft loss. We describe the first reported case of successful reversal of refractory PT-TMA with eculizumab in India. It highlights the importance of prompt diagnosis and benefit from an early initiation of eculizumab therapy in refractory cases.

4.
Proc Natl Acad Sci U S A ; 121(11): e2307813120, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38437570

RESUMEN

Lipid nanoparticles (LNPs) largely rely on ionizable lipids to yield successful nucleic acid delivery via electrostatic disruption of the endosomal membrane. Here, we report the identification and evaluation of ionizable lipids containing a thiophene moiety (Thio-lipids). The Thio-lipids can be readily synthesized via the Gewald reaction, allowing for modular lipid design with functional constituents at various positions of the thiophene ring. Through the rational design of ionizable lipid structure, we prepared 47 Thio-lipids and identified some structural criteria required in Thio-lipids for efficient mRNA (messenger RNA) encapsulation and delivery in vitro and in vivo. Notably, none of the tested lipids have a pH-response profile like traditional ionizable lipids, potentially due to the electron delocalization in the thiophene core. Placement of the tails and localization of the ionizable headgroup in the thiophene core can endow the nanoparticles with the capability to reach various tissues. Using high-throughput formulation and barcoding techniques, we optimized the formulations to select two top lipids-20b and 29d-and investigated their biodistribution in mice. Lipid 20b enabled LNPs to transfect the liver and spleen, and 29d LNP transfected the lung and spleen. Unexpectedly, LNP with lipid 20b was especially potent in mRNA delivery to the retina with no acute toxicity, leading to the successful delivery to the photoreceptors and retinal pigment epithelium in non-human primates.


Asunto(s)
Pulmón , Retina , Animales , Ratones , Distribución Tisular , ARN Mensajero/genética , Lípidos
5.
Eur Heart J Case Rep ; 8(3): ytae098, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38454961

RESUMEN

Background: Primary percutaneous intervention (PPCI) of the saphenous vein graft (SVG) is associated with a high risk of distal embolization and no reflow, since SVG lesions are often very friable and have a large thrombotic burden. We report a case of successful PPCI of the SVG using guide catheter thrombectomy with novel double wire technique. Case summary: A 60-year-old male with a past history of coronary artery bypass grafting presented with acute thrombotic occlusion of the SVG to the obtuse marginal graft. Despite appropriate pharmacotherapy (GPIIb/IIIa inhibitors) and thrombosuction, there was a large residual thrombus burden with poor distal flow. In the present case, we decided to perform guide catheter thrombosuction. An exchange length floppy 0.014' wire was passed alongside the pre-existing wire and the 6 Fr JR guide catheter was exchanged for a less traumatic 5 Fr JR guide catheter over the exchange wire. The first wire was kept distally in the vessel along the guiding catheter to maintain the access to the graft vessel. The 5 Fr JR guide catheter was slowly advanced over the wire to the distal portion of the graft, keeping the other wire in the distal portion of the graft to maintain access. A large amount of thrombus was aspirated and the patient improved dramatically. Discussion: This double wire technique is an effortless and novel way to maintain access to the distal vasculature of the occluded artery, while the guide can be safely intubated deep into the coronary artery that helps in removing a very large amount of thrombus because of their larger internal lumen.

6.
Indian Heart J ; 76(1): 67-70, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38309470

RESUMEN

BACKGROUND: Genetic polymorphism in endothelial Nitric Oxide Synthase (eNOS) are associated with occurrence of multiple cardiovascular diseases (CVDs). METHODS: This study included 300 young ST-segment elevation myocardial infarction (STEMI) patients and 300 healthy controls. STEMI patients were divided into two groups: premature coronary artery disease [CAD] (STEMI<40 years of age) and older STEMI (>40 years of age). Genetic polymorphisms in the eNOS gene (894G/T) was evaluated in both subjects and controls. Plasma levels of nitric oxide (NO) were estimated for both patients as well as controls. RESULTS: Mean age of the study population was 49.7 ± 9.2 years with premature CAD being present in 58 (19.3 %) patients. No significant difference at genotypic (P = 0.589, odds ratio (OR) = 0.9, 95 % CI = 0.6-1.6) and allelic level (P = 0.173, OR = 1.2, 95 % CI = 0.9-1.4) was observed between STEMI patients and healthy controls. Genotype 894 TT had significantly higher frequency in STEMI patients >40 years (P = 0.047, OR: 2.5; 95 % CI = 1.0-6.0). No significant difference at genotypic (P = 0.279) and allelic level (P = 0.493) was observed between premature CAD (STEMI age <40 years) and healthy controls. NO levels (131 ± 59.6 µM vs 118.11 ± 49.96 µM; P = 0.001) was significantly higher in healthy controls as compared to STEMI patients >40 years of age (P= 0.001). CONCLUSION: There was significant association of eNOS gene polymorphism Glu298Asp with STEMI patients > 40 years. However, this association was not observed in premature CAD patients. Lower levels of NO in STEMI patients >40 years suggests its potential role as a marker of CVD.


Asunto(s)
Enfermedad de la Arteria Coronaria , Infarto del Miocardio con Elevación del ST , Adulto , Humanos , Persona de Mediana Edad , Enfermedad de la Arteria Coronaria/epidemiología , Genotipo , Óxido Nítrico , Óxido Nítrico Sintasa de Tipo III/genética , Polimorfismo Genético , Factores de Riesgo , Infarto del Miocardio con Elevación del ST/diagnóstico , Infarto del Miocardio con Elevación del ST/genética
7.
Urol Oncol ; 42(3): 71.e9-71.e18, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38278631

RESUMEN

OBJECTIVES: Lack of strict indications in current guidelines have led to significant variation in management patterns of small renal masses. The impact of the urologist on the management approach for patients with small renal masses has not been explored previously. MATERIALS AND METHODS: Using the linked Surveillance, Epidemiology, and End Results-Medicare database, patients aged ≥66 years diagnosed with small renal masses from January 1, 2004 to December 31, 2013 were identified and assigned to primary urologists. Mixed-effects logistic models were used to evaluate factors associated with different management approaches, estimate urologist-level probabilities of each approach, assess management variation, and determine urologist impact on choice of approach. RESULTS: A total of 12,402 patients with 2,794 corresponding primary urologists were included in the study. At the individual urologist level, the estimated case-adjusted probability of different approaches varied markedly: nonsurgical management (mean, 12.8%; range, 4.9%-36.1%); thermal ablation (mean, 10.8%; range, 2.4%-66.3%); partial nephrectomy (mean, 30.1%; range, 10.1%-66.6%); and radical nephrectomy (mean, 40.4%; range, 17.7%-71.6%). Compared to patient and tumor characteristics, the primary urologist was a more influential measured factor, accounting for 13.6% (vs. 12.9%), 33.8% (vs. 2.1%), 15.1% (vs. 8.4%), and 13.5% (vs. 4.0%) of the variation in management choice for nonsurgical management, thermal ablation, partial nephrectomy, and radical nephrectomy, respectively. CONCLUSIONS: Significant variation exists in the management of small renal masses and appears to be driven primarily by urologist preference and practice patterns. Our findings emphasize the need for unified guidance regarding management of these masses to reduce unwarranted variation in care.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Anciano , Estados Unidos , Carcinoma de Células Renales/cirugía , Carcinoma de Células Renales/patología , Neoplasias Renales/cirugía , Neoplasias Renales/patología , Urólogos , Estudios de Cohortes , Medicare , Nefrectomía
8.
Urol Case Rep ; 51: 102617, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38046259

RESUMEN

A 66 year old male with history of inflatable penile prosthesis (IPP) placement was incidentally diagnosed with a 5 cm inguinal mass abutting the IPP reservoir after prostate MRI performed for an elevated PSA. This was surgically resected en bloc with his ipsilateral testicle and IPP reservoir, with final pathology demonstrating a high-grade round cell NUTM::CIC fusion sarcoma. Management is primarily surgical, though patients with high-risk features may require adjuvant chemoradiation.

9.
Biosci Rep ; 43(11)2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-37975243

RESUMEN

Acute high-altitude (HA) exposure can induce several pathologies. Dexamethasone (DEX) can be taken prophylactically to prevent HA disease, but the mechanism by which it acts in this setting is unclear. We studied the transcriptome of peripheral blood mononuclear cells (PBMCs) from 16 subjects at low altitude (LA, 225 m) and then 3 days after acute travel to HA (3500 m) during the India-Leh-Dexamethasone-Expedition-2020 (INDEX2020). Half of the participants received oral DEX prophylaxis 4 mg twice daily in an unblinded manner, starting 1 day prior to travel to HA, and 12 h prior to the first PBMC collection. PBMC transcriptome data were obtained from 16 subjects, half of whom received DEX. The principal component analysis demonstrated a clear separation of the groups by altitude and treatment. HA exposure resulted in a large number of gene expression changes, particularly in pathways of inflammation or the regulation of cell division, translation, or transcription. DEX prophylaxis resulted in changes in fewer genes, particularly in immune pathways. The gene sets modulated by HA and DEX were distinct. Deconvolution analysis to assess PBMC subpopulations suggested changes in B-cell, T-cell, dendritic cell, and myeloid cell numbers with HA and DEX exposures. Acute HA travel and DEX prophylaxis induce significant changes in the PBMC transcriptome. The observed benefit of DEX prophylaxis against HA disease may be mediated by suppression of inflammatory pathways and changing leukocyte population distributions.


Asunto(s)
Dexametasona , Leucocitos Mononucleares , Humanos , Altitud , Dexametasona/farmacología , Inflamación , Transcriptoma
10.
Cardiol Res ; 14(5): 360-369, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37936627

RESUMEN

Background: The short-term clinical outcomes of first-generation thicker-strut durable polymer-based drug-eluting stents (DES) have been widely examined. However, there is a scarcity on qualitative research on the long-term usage of DES that evaluated the thinner strut biodegradable stents for coronary artery disease. Hence, we sought to investigate the long-term safety and performance of thinner strut biodegradable polymer-based BioMime sirolimus-eluting coronary stent system in real-world patients with symptomatic ischemic heart disease. Methods: This was a retrospective, observational, single-center, post-marketing clinical follow-up study. The primary endpoints were the incidence of major adverse cardiac events (MACE), defined as a composite of cardiac death, myocardial infarction (MI) attributed to target vessel revascularization (TVR), and target lesion revascularization (TLR) at 1-, 2-, 3- and 4-year follow-ups. The secondary endpoints were cardiac death, MI, TLR, TVR, device and procedural success rates, and stent thrombosis (ST). Results: In all, 1,188 consecutive patients were enrolled, and 1,333 (1,257 de novo and 76 in-stent restenotic lesions) out of 1,565 lesions were treated with the study device. The mean age of patients was 53.26 ± 10.31 years and 86.2% were male. The quantitative coronary angiographic derived mean lesion length and diameter were 29.62 ± 9.62 mm and 3.01 ± 0.29 mm, respectively. The average length and diameter of the study device implanted were 30.89 ± 6.31 mm and 3.17 ± 0.25 mm, respectively. The cumulative incidence of MACE at 1-, 2-, 3-, and 4 years was 0.61%, 1.47%, 2.08%, and 3.40%, respectively, and cumulative deaths due to cardiac causes were 0.61%, 1.13%, 1.22%, and 1.83%, respectively. There were no cases of TLR or TVR at 1-year follow-up. The cumulative rate of TLR at 2-, 3-, and 4 years was 0.35%, 0.87%, and 1.57%, respectively, while that of TVR was 0.61%, 1.47%, and 2.35%, respectively. Three (0.3%) incidences of probable ST occurred during the 6-month follow-up; no new cases were reported further. In subgroup analysis, MACEs were comparable across the long- and short-length stent groups through 4-year follow-up. Conclusions: This long-term study demonstrates the safety and performance of the ultra-thin BioMime sirolimus-eluting stent with satisfactory clinical outcomes in patients with symptomatic ischemic heart disease in real-world scenario.

12.
Nat Microbiol ; 8(11): 2154-2169, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37884813

RESUMEN

Malaria-associated pathogenesis such as parasite invasion, egress, host cell remodelling and antigenic variation requires concerted action by many proteins, but the molecular regulation is poorly understood. Here we have characterized an essential Plasmodium-specific Apicomplexan AP2 transcription factor in Plasmodium falciparum (PfAP2-P; pathogenesis) during the blood-stage development with two peaks of expression. An inducible knockout of gene function showed that PfAP2-P is essential for trophozoite development, and critical for var gene regulation, merozoite development and parasite egress. Chromatin immunoprecipitation sequencing data collected at timepoints matching the two peaks of pfap2-p expression demonstrate PfAP2-P binding to promoters of genes controlling trophozoite development, host cell remodelling, antigenic variation and pathogenicity. Single-cell RNA sequencing and fluorescence-activated cell sorting revealed de-repression of most var genes in Δpfap2-p parasites. Δpfap2-p parasites also overexpress early gametocyte marker genes, indicating a regulatory role in sexual stage conversion. We conclude that PfAP2-P is an essential upstream transcriptional regulator at two distinct stages of the intra-erythrocytic development cycle.


Asunto(s)
Malaria , Parásitos , Plasmodium , Animales , Malaria/parasitología , Regulación de la Expresión Génica , Plasmodium falciparum/genética
13.
J Vasc Surg Cases Innov Tech ; 9(3): 101202, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37799829

RESUMEN

This case series highlights that extra-adrenal and recurrent pheochromocytomas can require en bloc vascular resection to achieve negative margins. Through this series of cases performed in a multidisciplinary fashion, we aim to highlight the technical aspects of these cases that can add to their complexity. Vascular invasion alone should not preclude an otherwise feasible oncologic resection.

15.
PLoS One ; 18(9): e0291090, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37656727

RESUMEN

BACKGROUND: COVID-19 vaccines are highly immunogenic but cardiovascular effects of these vaccines have not been properly elucidated. OBJECTIVES: To determine impact of COVID-19 vaccination on mortality following acute myocardial infarction (AMI). METHODS: This was a single center retrospective observation study among patients with AMI enrolled in the the North India ST-Elevation Myocardial Infarction (NORIN-STEMI) registry. In all the enrolled patients, data regarding patient's vaccination status including details on type of vaccine, date of vaccination and adverse effects were obtained. All enrolled subjects were followed up for a period of six months. The primary outcome of the study was all-cause mortality both at one month and at six months of follow-up. Propensity-weighted score logistic regression model using inverse probability of treatment weighting was used to determine the impact of vaccination status on all-cause mortality. RESULTS: A total of 1578 subjects were enrolled in the study of whom 1086(68.8%) were vaccinated against COVID-19 while 492(31.2%) were unvaccinated. Analysis of the temporal trends of occurrence of AMI post vaccination did not show a specific clustering of AMI at any particular time. On 30-day follow-up, all-cause mortality occurred in 201(12.7%) patients with adjusted odds of mortality being significantly lower in vaccinated group (adjusted odds ratio[aOR]: 0.58, 95% CI: 0.47-0.71). Similarly, at six months of follow-up, vaccinated AMI group had lower odds of mortality(aOR: 0.54, 95% CI: 0.44 to 0.65) as compared to non-vaccinated group. CONCLUSIONS: COVID-19 vaccines have shown to decrease all-cause mortality at 30 days and six months following AMI.


Asunto(s)
COVID-19 , Infarto del Miocardio , Humanos , Vacunas contra la COVID-19/efectos adversos , Puntaje de Propensión , Estudios Retrospectivos , Vacunación
16.
IEEE Trans Pattern Anal Mach Intell ; 45(12): 15005-15017, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37616134

RESUMEN

Multi-camera interference (MCI) is an important challenge faced by continuous-wave time-of-flight (C-ToF) cameras. In the presence of other cameras, a C-ToF camera may receive light from other cameras' sources, resulting in potentially large depth errors. We propose stochastic exposure coding (SEC), a novel approach to mitigate MCI. In SEC, the camera integration time is divided into multiple time slots. Each camera is turned on during a slot with an optimal probability to avoid interference while maintaining high signal-to-noise ratio (SNR). The proposed approach has the following benefits. First, SEC can filter out both the AC and DC components of interfering signals effectively, which simultaneously achieves high SNR and mitigates depth errors. Second, time-slotting in SEC enables 3D imaging without saturation in the high photon flux regime. Third, the energy savings due to camera turning on during only a fraction of integration time can be utilized to amplify the source peak power, which increases the robustness of SEC to ambient light. Lastly, SEC can be implemented without modifying the C-ToF camera's coding functions, and thus, can be used with a wide range of cameras with minimal changes. We demonstrate the performance benefits of SEC with thorough theoretical analysis, simulations and real experiments, across a wide range of imaging scenarios.

18.
JACC Asia ; 3(3): 431-442, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37396424

RESUMEN

Background: Low- and middle-income countries account for most of the global burden of coronary artery disease. There is a paucity of data regarding epidemiology and outcomes for ST-segment elevation myocardial infarction (STEMI) patients in these regions. Objectives: The authors studied the contemporary characteristics, practice patterns, outcomes, and sex differences in patients with STEMI in India. Methods: NORIN-STEMI (North India ST-Segment Elevation Myocardial Infarction Registry) is an investigator-initiated prospective cohort study of patients presenting with STEMI at tertiary medical centers in North India. Results: Of 3,635 participants, 16% were female patients, one-third were <50 years of age, 53% had a history of smoking, 29% hypertension, and 24% diabetes. The median time from symptom onset to coronary angiography was 71 hours; the majority (93%) presented first to a non-percutaneous coronary intervention (PCI)-capable facility. Almost all received aspirin, statin, P2Y12 inhibitors, and heparin on presentation; 66% were treated with PCI (98% femoral access) and 13% received fibrinolytics. The left ventricular ejection fraction was <40% in 46% of patients. The 30-day and 1-year mortality rates were 9% and 11%, respectively. Compared with male patients, female patients were less likely to receive PCI (62% vs 73%; P < 0.0001) and had a more than 2-fold greater 1-year mortality (22% vs 9%; adjusted HR: 2.1; 95% CI: 1.7-2.7; P < 0.001). Conclusions: In this contemporary registry of patients with STEMI in India, female patients were less likely to receive PCI after STEMI and had a higher 1-year mortality compared with male patients. These findings have important public health implications, and further efforts are required to reduce these gaps.

19.
Biochim Biophys Acta Mol Cell Res ; 1870(7): 119546, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37482133

RESUMEN

Multiple rounds of DNA replication take place in various stages of the life cycle in the human malaria parasite Plasmodium falciparum. Previous bioinformatics analysis has shown the presence of putative Autonomously Replicating Sequence (ARS) like sequences in the Plasmodium genome. However, the actual sites and frequency of replication origins in the P. falciparum genome based on experimental data still remain elusive. Minichromosome maintenance (MCM) proteins are recruited by the Origin recognition complex (ORC) to the origins of replication in eukaryotes including P. falciparum. We used PfMCM6 for chromatin immunoprecipitation followed by sequencing (ChIP-seq) in the quest for identification of putative replication origins in the parasite. PfMCM6 DNA binding sites annotation revealed high enrichment at exon regions. This is contrary to higher eukaryotes that show an inclination of origin sites towards transcriptional start sites. ChIP-seq results were further validated by ChIP-qPCR results as well as nascent strand abundance assay at the selected PfMCM6 enriched sites that also showed preferential binding of PfORC1 suggesting potential of these sites as origin sites. Further, PfMCM6 ChIP-seq data showed a positive correlation with previously published histone H4K8Ac genome-wide binding sites but not with H3K9Ac sites suggesting epigenetic control of replication initiation sites in the parasites. Overall, our data show the genome-wide distribution of PfMCM6 binding sites with their potential as replication origins in this deadly human pathogen that not only broadens our knowledge of parasite DNA replication and its unique biology, it may help to find new avenues for intervention processes.


Asunto(s)
Malaria Falciparum , Parásitos , Animales , Humanos , Plasmodium falciparum/genética , Parásitos/genética , Parásitos/metabolismo , Replicación del ADN/genética , Sitios de Unión , Malaria Falciparum/genética , Cromosomas/metabolismo , Componente 6 del Complejo de Mantenimiento de Minicromosoma/genética , Componente 6 del Complejo de Mantenimiento de Minicromosoma/metabolismo
20.
bioRxiv ; 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37293082

RESUMEN

Malaria pathogenicity results from the parasite's ability to invade, multiply within and then egress from the host red blood cell (RBC). Infected RBCs are remodeled, expressing antigenic variant proteins (such as PfEMP1, coded by the var gene family) for immune evasion and survival. These processes require the concerted actions of many proteins, but the molecular regulation is poorly understood. We have characterized an essential Plasmodium specific Apicomplexan AP2 (ApiAP2) transcription factor in Plasmodium falciparum (PfAP2-MRP; Master Regulator of Pathogenesis) during the intraerythrocytic developmental cycle (IDC). An inducible gene knockout approach showed that PfAP2-MRP is essential for development during the trophozoite stage, and critical for var gene regulation, merozoite development and parasite egress. ChIP-seq experiments performed at 16 hour post invasion (h.p.i.) and 40 h.p.i. matching the two peaks of PfAP2-MRP expression, demonstrate binding of PfAP2-MRP to the promoters of genes controlling trophozoite development and host cell remodeling at 16 h.p.i. and antigenic variation and pathogenicity at 40 h.p.i. Using single-cell RNA-seq and fluorescence-activated cell sorting, we show de-repression of most var genes in Δpfap2-mrp parasites that express multiple PfEMP1 proteins on the surface of infected RBCs. In addition, the Δpfap2-mrp parasites overexpress several early gametocyte marker genes at both 16 and 40 h.p.i., indicating a regulatory role in the sexual stage conversion. Using the Chromosomes Conformation Capture experiment (Hi-C), we demonstrate that deletion of PfAP2-MRP results in significant reduction of both intra-chromosomal and inter-chromosomal interactions in heterochromatin clusters. We conclude that PfAP2-MRP is a vital upstream transcriptional regulator controlling essential processes in two distinct developmental stages during the IDC that include parasite growth, chromatin structure and var gene expression.

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