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1.
Biochem Biophys Rep ; 38: 101677, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38511186

RESUMO

Eukaryotic messenger RNAs (mRNAs) transcend their predominant function of protein encoding by incorporating auxiliary components that ultimately contribute to their processing, transportation, translation, and decay. In doing so, additional layers of modifications are incorporated in mRNAs at post-transcriptional stage. Among them, N6-methyladenosine (m6A) is the most frequently found mRNA modification that plays crucial roles in plant development and stress response. In the overall mechanism of m6A methylation, key proteins classified based on their functions such as writers, readers, and erasers dynamically add, read, and subtract methyl groups respectively to deliver relevant functions in response to external stimuli. In this study, we identified 30 m6A regulatory genes (9 writers, 5 erasers, and 16 readers) in rice that encode 53 proteins (13 writers, 7 erasers, and 33 readers) where segmental duplication was found in one writer and four reader gene pairs. Reproductive cells such as sperm, anther and panicle showed high levels of expression for most of the m6A regulatory genes. Notably, writers like OsMTA, OsMTD, and OsMTC showed varied responses in different stress and infection contexts, with initial upregulation in response to early exposure followed by downregulation later. OsALKBH9A, a noteworthy eraser, displayed varied expression in response to different stresses at different time intervals, but upregulation in certain infections. Reader genes like OsECT5, OsCPSF30-L3, and OsECT8 showed continuous upregulation in exertion of all kinds of stress relevant here. Conversely, other reader genes along with OsECT11 and OsCPSF30-L2 were observed to be consistently downregulated. The apparent correlation between the expression patterns of m6A regulatory genes and stress modulation pathways in this study underscores the need for additional research to unravel their intricate regulatory mechanisms that could ultimately contribute to the substantial development of enhanced stress tolerance in rice through mRNA modification.

2.
J Clin Invest ; 134(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38015641

RESUMO

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with limited treatment options. Endothelial dysfunction plays a central role in the development and progression of PAH, yet the underlying mechanisms are incompletely understood. The endosome-lysosome system is important to maintain cellular health, and the small GTPase RAB7 regulates many functions of this system. Here, we explored the role of RAB7 in endothelial cell (EC) function and lung vascular homeostasis. We found reduced expression of RAB7 in ECs from patients with PAH. Endothelial haploinsufficiency of RAB7 caused spontaneous pulmonary hypertension (PH) in mice. Silencing of RAB7 in ECs induced broad changes in gene expression revealed via RNA-Seq, and RAB7-silenced ECs showed impaired angiogenesis and expansion of a senescent cell fraction, combined with impaired endolysosomal trafficking and degradation, suggesting inhibition of autophagy at the predegradation level. Furthermore, mitochondrial membrane potential and oxidative phosphorylation were decreased, and glycolysis was enhanced. Treatment with the RAB7 activator ML-098 reduced established PH in rats with chronic hypoxia/SU5416. In conclusion, we demonstrate for the first time to our knowledge the fundamental impairment of EC function by loss of RAB7, causing PH, and show RAB7 activation to be a potential therapeutic strategy in a preclinical model of PH.


Assuntos
Hipertensão Pulmonar , Animais , Humanos , Camundongos , Ratos , Hipertensão Pulmonar Primária Familiar/metabolismo , Hipertensão Pulmonar/etiologia , Hipóxia/metabolismo , Pulmão/metabolismo , Artéria Pulmonar/metabolismo
3.
Life Sci ; 328: 121880, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37356749

RESUMO

AIMS: Pulmonary oxygen toxicity is caused by exposure to a high fraction of inspired oxygen, which damages multiple cell types within the lung. The cellular basis for pulmonary oxygen toxicity includes mitochondrial dysfunction. The aim of this study was to identify the effects of hyperoxic exposure on mitochondrial bioenergetic and dynamic functions in pulmonary cells. MAIN METHODS: Mitochondrial respiration, inner membrane potential, dynamics (including motility), and distribution of mitochondrial bioenergetic capacity in two intracellular regions were quantified using cultured human lung microvascular endothelial cells, human pulmonary artery endothelial cells and A549 cells. Hyperoxic (95 % O2) exposures lasted 24, 48 and 72 h, durations relevant to mechanical ventilation in intensive care settings. KEY FINDINGS: Mitochondrial motility was altered following all hyperoxic exposures utilized in experiments. Inhomogeneities in inner membrane potential and respiration parameters were present in each cell type following hyperoxia. The partitioning of ATP-linked respiration was also hyperoxia-duration and cell type dependent. Hyperoxic exposure lasting 48 h or longer provoked the largest alterations in mitochondrial motility and the greatest decreases in ATP-linked respiration, with a suggestion of decreases in respiration complex protein levels. SIGNIFICANCE: Hyperoxic exposures of different durations produce intracellular inhomogeneities in mitochondrial dynamics and bioenergetics in pulmonary cells. Oxygen therapy is utilized commonly in clinical care and can induce undesirable decrements in bioenergy function needed to maintain pulmonary cell function and viability. There may be adjunctive or prophylactic measures that can be employed during hyperoxic exposures to prevent the mitochondrial dysfunction that signals the presence of oxygen toxcity.


Assuntos
Hiperóxia , Humanos , Hiperóxia/metabolismo , Células Endoteliais/metabolismo , Pulmão/metabolismo , Oxigênio/metabolismo , Metabolismo Energético , Trifosfato de Adenosina/metabolismo
4.
Sci Adv ; 9(11): eade6675, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36921041

RESUMO

Reactivation of the latent HIV-1 reservoir is a first step toward triggering reservoir decay. Here, we investigated the impact of the BAF complex inhibitor pyrimethamine on the reservoir of people living with HIV-1 (PLWH). Twenty-eight PLWH on suppressive antiretroviral therapy were randomized (1:1:1:1 ratio) to receive pyrimethamine, valproic acid, both, or no intervention for 14 days. The primary end point was change in cell-associated unspliced (CA US) HIV-1 RNA at days 0 and 14. We observed a rapid, modest, and significant increase in (CA US) HIV-1 RNA in response to pyrimethamine exposure, which persisted throughout treatment and follow-up. Valproic acid treatment alone did not increase (CA US) HIV-1 RNA or augment the effect of pyrimethamine. Pyrimethamine treatment did not result in a reduction in the size of the inducible reservoir. These data demonstrate that the licensed drug pyrimethamine can be repurposed as a BAF complex inhibitor to reverse HIV-1 latency in vivo in PLWH, substantiating its potential advancement in clinical studies.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Linfócitos T CD4-Positivos , Infecções por HIV/tratamento farmacológico , HIV-1/fisiologia , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , RNA , Ácido Valproico/farmacologia , Ativação Viral , Latência Viral
5.
bioRxiv ; 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36778418

RESUMO

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with limited treatment options. Endothelial dysfunction plays a central role in development and progression of PAH, yet the underlying mechanisms are incompletely understood. The endosome-lysosome system is important to maintain cellular health and the small GTPase RAB7 regulates many functions of this system. Here, we explored the role of RAB7 in endothelial cell (EC) function and lung vascular homeostasis. We found reduced expression of RAB7 in ECs from PAH patients. Endothelial haploinsufficiency of RAB7 caused spontaneous PH in mice. Silencing of RAB7 in ECs induced broad changes in gene expression revealed via RNA sequencing and RAB7 silenced ECs showed impaired angiogenesis, expansion of a senescent cell fraction, combined with impaired endolysosomal trafficking and degradation, which suggests inhibition of autophagy at the pre-degradation level. Further, mitochondrial membrane potential and oxidative phosphorylation were decreased, and glycolysis was enhanced. Treatment with the RAB7 activator ML-098 reduced established PH in chronic hypoxia/SU5416 rats. In conclusion, we demonstrate here for the first time the fundamental impairment of EC function by loss of RAB7 that leads to PH and show RAB7 activation as a potential therapeutic strategy in a preclinical model of PH.

6.
BMJ Glob Health ; 7(11)2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36319031

RESUMO

OBJECTIVE: Risk factors predisposing infants to community-acquired bacterial infections during the first 2 months of life are poorly understood in South Asia. Identifying risk factors for infection could lead to improved preventive measures and antibiotic stewardship. METHODS: Five sites in Bangladesh, India and Pakistan enrolled mother-child pairs via population-based pregnancy surveillance by community health workers. Medical, sociodemographic and epidemiological risk factor data were collected. Young infants aged 0-59 days with signs of possible serious bacterial infection (pSBI) and age-matched controls provided blood and respiratory specimens that were analysed by blood culture and real-time PCR. These tests were used to build a Bayesian partial latent class model (PLCM) capable of attributing the probable cause of each infant's infection in the ANISA study. The collected risk factors from all mother-child pairs were classified and analysed against the PLCM using bivariate and stepwise logistic multivariable regression modelling to determine risk factors of probable bacterial infection. RESULTS: Among 63 114 infants born, 14 655 were assessed and 6022 had signs of pSBI; of these, 81% (4859) provided blood samples for culture, 71% (4216) provided blood samples for quantitative PCR (qPCR) and 86% (5209) provided respiratory qPCR samples. Risk factors associated with bacterial-attributed infections included: low (relative risk (RR) 1.73, 95% credible interval (CrI) 1.42 to 2.11) and very low birth weight (RR 5.77, 95% CrI 3.73 to 8.94), male sex (RR 1.27, 95% CrI 1.07 to 1.52), breathing problems at birth (RR 2.50, 95% CrI 1.96 to 3.18), premature rupture of membranes (PROMs) (RR 1.27, 95% CrI 1.03 to 1.58) and being in the lowest three socioeconomic status quintiles (first RR 1.52, 95% CrI 1.07 to 2.16; second RR 1.41, 95% CrI 1.00 to 1.97; third RR 1.42, 95% CrI 1.01 to 1.99). CONCLUSION: Distinct risk factors: birth weight, male sex, breathing problems at birth and PROM were significantly associated with the development of bacterial sepsis across South Asian community settings, supporting refined clinical discernment and targeted use of antimicrobials.


Assuntos
Infecções Bacterianas , Infecções Comunitárias Adquiridas , Lactente , Recém-Nascido , Gravidez , Feminino , Humanos , Masculino , Estudos Longitudinais , Teorema de Bayes , Infecções Comunitárias Adquiridas/complicações , Infecções Comunitárias Adquiridas/epidemiologia , Fatores de Risco , Estudos de Coortes , Estudos de Casos e Controles , Índia/epidemiologia
7.
Front Cell Dev Biol ; 10: 1010232, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36340034

RESUMO

Mitochondria are cell organelles that play pivotal roles in maintaining cell survival, cellular metabolic homeostasis, and cell death. Mitochondria are highly dynamic entities which undergo fusion and fission, and have been shown to be very motile in vivo in neurons and in vitro in multiple cell lines. Fusion and fission are essential for maintaining mitochondrial homeostasis through control of morphology, content exchange, inheritance of mitochondria, maintenance of mitochondrial DNA, and removal of damaged mitochondria by autophagy. Mitochondrial motility occurs through mechanical and molecular mechanisms which translocate mitochondria to sites of high energy demand. Motility also plays an important role in intracellular signaling. Here, we review key features that mediate mitochondrial dynamics and explore methods to advance the study of mitochondrial motility as well as mitochondrial dynamics-related diseases and mitochondrial-targeted therapeutics.

8.
Bio Protoc ; 12(8): e4392, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35800100

RESUMO

The absence of long term, primary untransformed in vitro models that support hepatitis B virus (HBV) infection and replication have hampered HBV pre-clinical research, which was reflected in the absence of a curative therapy until recently. One of the limitations for in vitro HBV research has been the absence of high titer and pure recombinant HBV stocks, which, as we describe here, can be generated using simple, and reproducible protocols. In addition to infection of more conventional in vitro and in vivo liver model systems, recombinant high titer purified HBV stocks can also be used to efficiently infect differentiated human liver organoids, whose generation, maintenance, and infection is discussed in detail in a companion organoid protocol. Here, we also describe the protocols for the detection of specific viral read-outs, including HBV DNA in the supernatant of the cultures, covalently closed circular DNA (cccDNA) from intracellular DNA preparations, and HBV viral proteins and viral RNA, which can be detected within the cells, demonstrating the presence of a complete viral replication cycle in infected liver organoids. Although an evolving platform, the human liver organoid model system presents great potential as an exciting new tool to study HBV infection and progression to hepatocellular carcinoma (HCC) in primary cells, when combined with the use of high-titer and pure recombinant HBV stock for infection. Graphical abstract.

9.
Lancet Glob Health ; 10(7): e978-e988, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35714648

RESUMO

BACKGROUND: Precise enteric fever disease burden data are needed to inform prevention and control measures, including the use of newly available typhoid vaccines. We established the Surveillance for Enteric Fever in Asia Project (SEAP) to inform these strategies. METHODS: From September, 2016, to September, 2019, we conducted prospective clinical surveillance for Salmonella enterica serotype Typhi (S Typhi) and Paratyphi (S Paratyphi) A, B, and C at health facilities in predetermined catchment areas in Dhaka, Bangladesh; Kathmandu and Kavrepalanchok, Nepal; and Karachi, Pakistan. Patients eligible for inclusion were outpatients with 3 or more consecutive days of fever in the last 7 days; inpatients with suspected or confirmed enteric fever; patients with blood culture-confirmed enteric fever from the hospital laboratories not captured by inpatient or outpatient enrolment and cases from the laboratory network; and patients with non-traumatic ileal perforation under surgical care. We used a hybrid surveillance model, pairing facility-based blood culture surveillance with community surveys of health-care use. Blood cultures were performed for enrolled patients. We calculated overall and age-specific typhoid and paratyphoid incidence estimates for each study site. Adjusted estimates accounted for the sensitivity of blood culture, the proportion of eligible individuals who consented and provided blood, the probability of care-seeking at a study facility, and the influence of wealth and education on care-seeking. We additionally calculated incidence of hospitalisation due to typhoid and paratyphoid. FINDINGS: A total of 34 747 patients were enrolled across 23 facilitates (six tertiary hospitals, surgical wards of two additional hospitals, and 15 laboratory network sites) during the study period. Of the 34 303 blood cultures performed on enrolled patients, 8705 (26%) were positive for typhoidal Salmonella. Adjusted incidence rates of enteric fever considered patients in the six tertiary hospitals. Adjusted incidence of S Typhi, expressed per 100 000 person-years, was 913 (95% CI 765-1095) in Dhaka. In Nepal, the adjusted typhoid incidence rates were 330 (230-480) in Kathmandu and 268 (202-362) in Kavrepalanchok. In Pakistan, the adjusted incidence rates per hospital site were 176 (144-216) and 103 (85-126). The adjusted incidence rates of paratyphoid (of which all included cases were due to S Paratyphi A) were 128 (107-154) in Bangladesh, 46 (34-62) and 81 (56-118) in the Nepal sites, and 23 (19-29) and 1 (1-1) in the Pakistan sites. Adjusted incidence of hospitalisation was high across sites, and overall, 2804 (32%) of 8705 patients with blood culture-confirmed enteric fever were hospitalised. INTERPRETATION: Across diverse communities in three south Asian countries, adjusted incidence exceeded the threshold for "high burden" of enteric fever (100 per 100 000 person-years). Incidence was highest among children, although age patterns differed across sites. The substantial disease burden identified highlights the need for control measures, including improvements to water and sanitation infrastructure and the implementation of typhoid vaccines. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Febre Paratifoide , Febre Tifoide , Vacinas Tíficas-Paratíficas , Bangladesh/epidemiologia , Criança , Humanos , Incidência , Nepal/epidemiologia , Paquistão/epidemiologia , Febre Paratifoide/epidemiologia , Febre Paratifoide/prevenção & controle , Estudos Prospectivos , Salmonella , Salmonella paratyphi A , Febre Tifoide/epidemiologia , Febre Tifoide/prevenção & controle
10.
Small ; 18(26): e2107571, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35620959

RESUMO

The integration of nanoarchitectonics and hydrogel into conventional biosensing platforms offers the opportunities to design physically and chemically controlled and optimized soft structures with superior biocompatibility, better immobilization of biomolecules, and specific and sensitive biosensor design. The physical and chemical properties of 3D hydrogel structures can be modified by integrating with nanostructures. Such modifications can enhance their responsiveness to mechanical, optical, thermal, magnetic, and electric stimuli, which in turn can enhance the practicality of biosensors in clinical settings. This review describes the synthesis and kinetics of gel networks and exploitation of nanostructure-integrated hydrogels in biosensing. With an emphasis on different integration strategies of hydrogel with nanostructures, this review highlights the importance of hydrogel nanostructures as one of the most favorable candidates for developing ultrasensitive biosensors. Moreover, hydrogel nanoarchitectonics are also portrayed as a promising candidate for fabricating next-generation robust biosensors.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Hidrogéis/química , Nanoestruturas/química
11.
Bio Protoc ; 12(6): e4358, 2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35434190

RESUMO

Hepatitis B virus (HBV) infection represents a major public health problem infecting approximately 400 million people worldwide. Despite the availability of a preventive vaccine and anti-viral therapies, chronic HBV infection remains a major health issue because it increases the risk of developing liver cirrhosis and hepatocellular carcinoma (HCC). The lack of a relevant in vitro model for the study of the molecular mechanisms that drive HBV replication and latency, as well as HBV-related carcinogenesis, has been one of the major obstacles to the development of curative strategies. Here, we propose the use of human liver organoids as a platform for modeling HBV infection and related tumorigenesis. Human liver organoids can be seeded from both healthy and cirrhotic liver biopsies. They can be expanded in vitro when culturing in a medium containing a specific set of growth factors. When the culture medium is changed into a new medium containing growth factors that promote differentiation, organoids differentiate into functional hepatocytes, which makes them susceptible to infection with recombinant HBV. The novel in vitro primary model system described in this protocol can be utilized as a platform to study HBV pathogenesis and drug screening. Organoids generated from cirrhotic liver biopsies can be a potential tool for personalized medicine, and for modeling HCC and other liver diseases. Graphic abstract.

12.
Sci Rep ; 12(1): 4381, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35288583

RESUMO

In recent years, the nuclear power plant has received huge attention as it generates vast amounts of power at a lower cost. However, its creation of radioactive wastes is a major environmental concern. Therefore, the nuclear power plant requires a reliable and uninterrupted monitoring system as an essential part of it. Monitoring a nuclear power plant using wireless sensor networks is a convenient and popular practice now. This paper proposes a hybrid approach for monitoring wireless sensor networks in the context of a nuclear power plant in Bangladesh. Our hybrid approach enhances the lifespan of wireless sensor networks reducing power consumption and offering better connectivity of sensors. To do so, it uses both the topology maintenance and topology construction algorithms. We found that the HGETRecRot topology maintenance algorithm enhances the network lifetime compared to other algorithms. This algorithm increases the communication and sensing coverage area but decreases the network performance. We also propose a prediction model, based on linear regression algorithm, that predicts the best combination of topology maintenance and topology construction algorithms.


Assuntos
Redes de Comunicação de Computadores , Tecnologia sem Fio , Algoritmos , Longevidade , Centrais Nucleares
13.
Elife ; 102021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34328417

RESUMO

The molecular events that drive hepatitis B virus (HBV)-mediated transformation and tumorigenesis have remained largely unclear, due to the absence of a relevant primary model system. Here we propose the use of human liver organoids as a platform for modeling HBV infection and related tumorigenesis. We first describe a primary ex vivo HBV-infection model derived from healthy donor liver organoids after challenge with recombinant virus or HBV-infected patient serum. HBV-infected organoids produced covalently closed circular DNA (cccDNA) and HBV early antigen (HBeAg), expressed intracellular HBV RNA and proteins, and produced infectious HBV. This ex vivo HBV-infected primary differentiated hepatocyte organoid platform was amenable to drug screening for both anti-HBV activity and drug-induced toxicity. We also studied HBV replication in transgenically modified organoids; liver organoids exogenously overexpressing the HBV receptor sodium taurocholate co-transporting polypeptide (NTCP) after lentiviral transduction were not more susceptible to HBV, suggesting the necessity for additional host factors for efficient infection. We also generated transgenic organoids harboring integrated HBV, representing a long-term culture system also suitable for viral production and the study of HBV transcription. Finally, we generated HBV-infected patient-derived liver organoids from non-tumor cirrhotic tissue of explants from liver transplant patients. Interestingly, transcriptomic analysis of patient-derived liver organoids indicated the presence of an aberrant early cancer gene signature, which clustered with the hepatocellular carcinoma (HCC) cohort on The Cancer Genome Atlas Liver Hepatocellular Carcinoma dataset and away from healthy liver tissue, and may provide invaluable novel biomarkers for the development of HCC and surveillance in HBV-infected patients.


Assuntos
Carcinoma Hepatocelular/virologia , Hepatite B/virologia , Neoplasias Hepáticas/virologia , Organoides/virologia , Células Hep G2 , Hepatite B/complicações , Vírus da Hepatite B/patogenicidade , Humanos , Fígado/patologia , Fígado/virologia , Doadores Vivos , Modelos Biológicos , Replicação Viral
14.
Life Sci ; 278: 119616, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34015286

RESUMO

AIMS: Hyperbaric oxygen therapy (HBOT), used to promote wound healing, has limited efficacy in many clinical conditions. Wound healing exerts bioenergetic demands on cells that can exceed their intrinsic bioenergetic capacity to proliferate and migrate. The aim of this investigation was to quantify the effects of HBOT on mitochondrial dynamics and bioenergetics functions in cells relevant to wound healing. MAIN METHODS: High-resolution respirometry and fluorescence microscopy were used to quantify mitochondrial respiration, intermembrane potential, dynamics, including motility, and the intracellular distribution of mitochondrial bioenergetic capacity partitioned into perinuclear and cell peripheral regions in cultured human dermal fibroblasts. Cells were subjected to a range of gas mixtures and hyperbaric pressures, including conditions utilized in clinical care. KEY FINDINGS: Motility was reduced immediately following all HBOT exposures utilized in experiments. Inhomogeneities in intermembrane potential and respiration parameters were produced by different HBOT conditions. The partitioning of ATP-linked respiration was also HBOT-condition dependent. Application of HBOT at common clinical pressure and oxygen conditions resulted in the largest immediate decrement in mitochondrial motility and reductions in ATP-linked respiration in both the cell periphery and perinuclear zones. Aberrations in motility and respiration were also present 6 h after exposure. SIGNIFICANCE: HBOT produces intracellular distinctions and inhomogeneities in mitochondrial dynamics and bioenergetics. HBOT as is commonly applied in clinical medicine induced undesirable and persistent alterations in bioenergy function needed to support cell migration and/or proliferation. There may be alternative HBOT parameters that more effectively engender maintenance and adequacy of intracellular bioenergy supply to promote wound healing.


Assuntos
Metabolismo Energético , Fibroblastos/metabolismo , Dinâmica Mitocondrial , Oxigênio/metabolismo , Linhagem Celular , Humanos , Oxigenoterapia Hiperbárica , Mitocôndrias/metabolismo , Pele/citologia , Cicatrização
15.
Inform Med Unlocked ; 24: 100569, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33846694

RESUMO

The coronavirus disease 2019 (COVID-19) is an ongoing pandemic caused by an RNA virus termed as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). SARS-CoV-2 possesses an almost 30kbp long genome. The genome contains open-reading frame 1ab (ORF1ab) gene, the largest one of SARS-CoV-2, encoding polyprotein PP1ab and PP1a responsible for viral transcription and replication. Several vaccines have already been approved by the respective authorities over the world to develop herd immunity among the population. In consonance with this effort, RNA interference (RNAi) technology holds the possibility to strengthen the fight against this virus. Here, we have implemented a computational approach to predict potential short interfering RNAs including small interfering RNAs (siRNAs) and microRNAs (miRNAs), which are presumed to be intrinsically active against SARS-CoV-2. In doing so, we have screened miRNA library and siRNA library targeting the ORF1ab gene. We predicted the potential miRNA and siRNA candidate molecules utilizing an array of bioinformatic tools. By extending the analysis, out of 24 potential pre-miRNA hairpins and 131 siRNAs, 12 human miRNA and 10 siRNA molecules were sorted as potential therapeutic agents against SARS-CoV-2 based on their GC content, melting temperature (Tm), heat capacity (Cp), hybridization and minimal free energy (MFE) of hybridization. This computational study is focused on lessening the extensive time and labor needed in conventional trial and error based wet lab methods and it has the potential to act as a decent base for future researchers to develop a successful RNAi therapeutic.

16.
BMC Pregnancy Childbirth ; 21(Suppl 1): 234, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33765951

RESUMO

BACKGROUND: Observation of care at birth is challenging with multiple, rapid and potentially concurrent events occurring for mother, newborn and placenta. Design of electronic data (E-data) collection needs to account for these challenges. The Every Newborn Birth Indicators Research Tracking in Hospitals (EN-BIRTH) was an observational study to assess measurement of indicators for priority maternal and newborn interventions and took place in five hospitals in Bangladesh, Nepal and Tanzania (July 2017-July 2018). E-data tools were required to capture individually-linked, timed observation of care, data extraction from hospital register-records or case-notes, and exit-survey data from women. METHODS: To evaluate this process for EN-BIRTH, we employed a framework organised around five steps for E-data design, data collection and implementation. Using this framework, a mixed methods evaluation synthesised evidence from study documentation, standard operating procedures, stakeholder meetings and design workshops. We undertook focus group discussions with EN-BIRTH researchers to explore experiences from the three different country teams (November-December 2019). Results were organised according to the five a priori steps. RESULTS: In accordance with the five-step framework, we found: 1) Selection of data collection approach and software: user-centred design principles were applied to meet the challenges for observation of rapid, concurrent events around the time of birth with time-stamping. 2) Design of data collection tools and programming: required extensive pilot testing of tools to be user-focused and to include in-built error messages and data quality alerts. 3) Recruitment and training of data collectors: standardised with an interactive training package including pre/post-course assessment. 4) Data collection, quality assurance, and management: real-time quality assessments with a tracking dashboard and double observation/data extraction for a 5% case subset, were incorporated as part of quality assurance. Internet-based synchronisation during data collection posed intermittent challenges. 5) Data management, cleaning and analysis: E-data collection was perceived to improve data quality and reduce time cleaning. CONCLUSIONS: The E-Data system, custom-built for EN-BIRTH, was valued by the site teams, particularly for time-stamped clinical observation of complex multiple simultaneous events at birth, without which the study objectives could not have been met. However before selection of a custom-built E-data tool, the development time, higher training and IT support needs, and connectivity challenges need to be considered against the proposed study or programme's purpose, and currently available E-data tool options.


Assuntos
Registros Eletrônicos de Saúde/organização & administração , Sistemas de Informação Hospitalar/organização & administração , Hospitais/estatística & dados numéricos , Assistência Perinatal/organização & administração , Bangladesh , Confiabilidade dos Dados , Registros Eletrônicos de Saúde/estatística & dados numéricos , Feminino , Grupos Focais , Sistemas de Informação Hospitalar/estatística & dados numéricos , Humanos , Recém-Nascido , Nepal , Assistência Perinatal/estatística & dados numéricos , Gravidez , Software , Inquéritos e Questionários , Tanzânia
17.
Cancer Lett ; 506: 35-44, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33675983

RESUMO

Hepatitis B Virus (HBV) infection is a leading cause of chronic liver cirrhosis and hepatocellular carcinoma (HCC) with an estimated 400 million people infected worldwide. The precise molecular mechanisms underlying HBV replication and tumorigenesis have remained largely uncharacterized due to the lack of a primary cell model to study HBV, a virus that exhibits stringent host species and cell-type specificity. Organoid technology has recently emerged as a powerful tool to investigate human diseases in a primary 3D cell-culture system that maintains the organisation and functionality of the tissue of origin. In this review, we describe the utilisation of human liver organoid platforms to study HBV. We first present the different categories of liver organoids and their demonstrated ability to support the complete HBV replication cycle. We then discuss the potential applications of liver organoids in investigating HBV infection and replication, related tumorigenesis and novel HBV-directed therapies. Liver organoids can be genetically modified, patient-derived, expanded and biobanked, thereby serving as a clinically-relevant, human, primary cell-derived platform to investigate HBV. Finally, we provide insights into the future applications of this powerful technology in the context of HBV-infection and HCC.


Assuntos
Hepatite B/complicações , Neoplasias Hepáticas/etiologia , Fígado/citologia , Organoides/virologia , Replicação Viral/fisiologia , Carcinogênese , Vírus da Hepatite B/fisiologia , Humanos , Fígado/virologia
18.
Clin Nutr ; 40(3): 1405-1412, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32933783

RESUMO

BACKGROUND & AIMS: International guidance advocates the avoidance of prolonged preoperative fasting due to its negative impact on perioperative hydration. This study aimed to assess the adherence to these guidelines for fasting in patients undergoing elective and emergency surgery in the East Midlands region of the UK. METHODS: This prospective audit was performed over a two-month period at five National Health Service (NHS) Trusts across the East Midlands region of the UK. Demographic data, admission and operative details, and length of preoperative fasting were collected on adult patients listed for emergency and elective surgery. RESULTS: Of the 343 surgical patients included within the study, 50% (n = 172) were male, 78% (n = 266) had elective surgery and 22% (n = 77) underwent emergency surgery. Overall median fasting times (Q1, Q3) were 16.1 (13.0, 19.4) hours for food and 5.8 (3.5, 10.7) hours for clear fluids. Prolonged fasting >12 h was documented in 73% (n = 250) for food, and 21% (n = 71) for clear fluids. Median fasting times from clear fluids and food were longer in the those undergoing emergency surgery when compared with those undergoing elective surgery: 13.0 (6.4, 22.6) vs. 4.9 (3.3, 7.8) hours, and 22.0 (14.0, 37.4) vs. 15.6 (12.9, 17.8) hours respectively, p < 0.0001. CONCLUSIONS: Despite international consensus on the duration of preoperative fasting, patients continue to fast from clear fluids and food for prolonged lengths of time. Patients admitted for emergency surgery were more likely to fast for longer than those having elective surgery.


Assuntos
Jejum/efeitos adversos , Cuidados Pré-Operatórios/métodos , Procedimentos Cirúrgicos Operatórios/métodos , Adulto , Idoso , Auditoria Clínica , Desidratação/etiologia , Procedimentos Cirúrgicos Eletivos , Tratamento de Emergência , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Fatores de Tempo , Reino Unido
19.
Lancet Glob Health ; 9(3): e267-e279, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33333015

RESUMO

BACKGROUND: Progress in reducing maternal and neonatal deaths and stillbirths is impeded by data gaps, especially regarding coverage and quality of care in hospitals. We aimed to assess the validity of indicators of maternal and newborn health-care coverage around the time of birth in survey data and routine facility register data. METHODS: Every Newborn-BIRTH Indicators Research Tracking in Hospitals was an observational study in five hospitals in Bangladesh, Nepal, and Tanzania. We included women and their newborn babies who consented on admission to hospital. Exclusion critiera at admission were no fetal heartbeat heard or imminent birth. For coverage of uterotonics to prevent post-partum haemorrhage, early initiation of breastfeeding (within 1 h), neonatal bag-mask ventilation, kangaroo mother care (KMC), and antibiotics for clinically defined neonatal infection (sepsis, pneumonia, or meningitis), we collected time-stamped, direct observation or case note verification data as gold standard. We compared data reported via hospital exit surveys and via hospital registers to the gold standard, pooled using random effects meta-analysis. We calculated population-level validity ratios (measured coverage to observed coverage) plus individual-level validity metrics. FINDINGS: We observed 23 471 births and 840 mother-baby KMC pairs, and verified the case notes of 1015 admitted newborn babies regarding antibiotic treatment. Exit-survey-reported coverage for KMC was 99·9% (95% CI 98·3-100) compared with observed coverage of 100% (99·9-100), but exit surveys underestimated coverage for uterotonics (84·7% [79·1-89·5]) vs 99·4% [98·7-99·8] observed), bag-mask ventilation (0·8% [0·4-1·4]) vs 4·4% [1·9-8·1]), and antibiotics for neonatal infection (74·7% [55·3-90·1] vs 96·4% [94·0-98·6] observed). Early breastfeeding coverage was overestimated in exit surveys (53·2% [39·4-66·8) vs 10·9% [3·8-21·0] observed). "Don't know" responses concerning clinical interventions were more common in the exit survey after caesarean birth. Register data underestimated coverage of uterotonics (77·9% [37·8-99·5] vs 99·2% [98·6-99·7] observed), bag-mask ventilation (4·3% [2·1-7·3] vs 5·1% [2·0-9·6] observed), KMC (92·9% [84·2-98·5] vs 100% [99·9-100] observed), and overestimated early breastfeeding (85·9% (58·1-99·6) vs 12·5% [4·6-23·6] observed). Inter-hospital heterogeneity was higher for register-recorded coverage than for exit survey report. Even with the same register design, accuracy varied between hospitals. INTERPRETATION: Coverage indicators for newborn and maternal health care in exit surveys had low accuracy for specific clinical interventions, except for self-report of KMC, which had high sensitivity after admission to a KMC ward or corner and could be considered for further assessment. Hospital register design and completion are less standardised than surveys, resulting in variable data quality, with good validity for the best performing sites. Because approximately 80% of births worldwide take place in facilities, standardising register design and information systems has the potential to sustainably improve the quality of data on care at birth. FUNDING: Children's Investment Fund Foundation and Swedish Research Council.


Assuntos
Países em Desenvolvimento , Serviços de Saúde Materno-Infantil/organização & administração , Indicadores de Qualidade em Assistência à Saúde/organização & administração , Inquéritos e Questionários/normas , Antibacterianos/provisão & distribuição , Antibacterianos/uso terapêutico , Aleitamento Materno/estatística & dados numéricos , Humanos , Recém-Nascido , Doenças do Recém-Nascido/tratamento farmacológico , Método Canguru/estatística & dados numéricos , Serviços de Saúde Materno-Infantil/normas , Hemorragia Pós-Parto/prevenção & controle , Indicadores de Qualidade em Assistência à Saúde/normas , Qualidade da Assistência à Saúde/normas , Reprodutibilidade dos Testes
20.
Reprod Health ; 17(Suppl 2): 148, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256775

RESUMO

BACKGROUND: The Global Network for Women's and Children's Health Research (Global Network, GN) has established the Maternal Newborn Health Registry (MNHR) to assess MNH outcomes over time. Bangladesh is the newest country in the GN and has implemented a full electronic MNH registry system, from married women surveillance to pregnancy enrollment and subsequent follow ups. METHOD: Like other GN sites, the Bangladesh MNHR is a prospective, population-based observational study that tracks pregnancies and MNH outcomes. The MNHR site is in the Ghatail and Kalihati sub-districts of the Tangail district. The study area consists of 12 registry clusters each of ~ 18,000-19,000 population. All pregnant women identified through a two-monthly house-to-house surveillance are enrolled in the registry upon consenting and followed up on scheduled visits until 42 days after pregnancy outcome. A comprehensive automated registry data capture system has been developed that allows for married women surveillance, pregnancy enrollment, and data collection during follow-up visits using a web-linked tablet-PC-based system. RESULT: During March-May 2019, a total of 56,064 households located were listed in the Bangladesh MNH registry site. Of the total 221,462 population covered, 49,269 were currently married women in reproductive age (CMWRA). About 13% CMWRA were less susceptible to pregnancy. Large variability was observed in selected contraceptive usage across clusters. Overall, 5% of the listed CMWRAs were reported as currently pregnant. CONCLUSION: In comparison to paper-pen capturing system electronic data capturing system (EDC) has advantages of less error-prone data collection, real-time data collection progress monitoring, data quality check and sharing. But the implementation of EDC in a resource-poor setting depends on technical infrastructure, skilled staff, software development, community acceptance and a data security system. Our experience of pregnancy registration, intervention coverage, and outcome tracking provides important contextualized considerations for both design and implementation of individual-level health information capturing and sharing systems.


Assuntos
Saúde da Criança , Saúde Materna , Sistema de Registros , Saúde da Mulher , Adolescente , Adulto , Bangladesh/epidemiologia , Criança , Eletrônica , Feminino , Humanos , Recém-Nascido , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Adulto Jovem
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