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The 9p21.3 cardiovascular disease locus is the most influential common genetic risk factor for coronary artery disease (CAD), accounting for â¼10%-15% of disease in non-African populations. The â¼60 kb risk haplotype is human-specific and lacks coding genes, hindering efforts to decipher its function. Here, we produce induced pluripotent stem cells (iPSCs) from risk and non-risk individuals, delete each haplotype using genome editing, and generate vascular smooth muscle cells (VSMCs). Risk VSMCs exhibit globally altered transcriptional networks that intersect with previously identified CAD risk genes and pathways, concomitant with aberrant adhesion, contraction, and proliferation. Unexpectedly, deleting the risk haplotype rescues VSMC stability, while expressing the 9p21.3-associated long non-coding RNA ANRIL induces risk phenotypes in non-risk VSMCs. This study shows that the risk haplotype selectively predisposes VSMCs to adopt a cell state associated with CAD phenotypes, defines new VSMC-based networks of CAD risk genes, and establishes haplotype-edited iPSCs as powerful tools for functionally annotating the human genome.
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Cromossomos Humanos Par 9 , Doença da Artéria Coronariana , Edição de Genes , Haplótipos , Células-Tronco Pluripotentes Induzidas , Polimorfismo de Nucleotídeo Único , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 9/genética , Cromossomos Humanos Par 9/metabolismo , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Feminino , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transcrição GênicaRESUMO
9p21.3 locus polymorphisms have the strongest correlation with coronary artery disease, but as a noncoding locus, disease connection is enigmatic. The lncRNA ANRIL found in 9p21.3 may regulate vascular smooth muscle cell (VSMC) phenotype to contribute to disease risk. We observed significant heterogeneity in induced pluripotent stem cell-derived VSMCs from patients homozygous for risk versus isogenic knockout or nonrisk haplotypes. Subpopulations of risk haplotype cells exhibited variable morphology, proliferation, contraction, and adhesion. When sorted by adhesion, risk VSMCs parsed into synthetic and contractile subpopulations, i.e., weakly adherent and strongly adherent, respectively. Of note, >90% of differentially expressed genes coregulated by haplotype and adhesion and were associated with Rho GTPases, i.e., contractility. Weakly adherent subpopulations expressed more short isoforms of ANRIL, and when overexpressed in knockout cells, ANRIL suppressed adhesion, contractility, and αSMA expression. These data suggest that variable lncRNA penetrance may drive mixed functional outcomes that confound pathology.
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Doença da Artéria Coronariana , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Músculo Liso Vascular/metabolismo , Plasticidade Celular/genética , Doença da Artéria Coronariana/genética , Fenótipo , Miócitos de Músculo Liso/metabolismo , Proliferação de Células , Células CultivadasRESUMO
Management of chronic obesity-associated metabolic disorders is a key challenge for biomedical researchers. During chronic obesity, visceral adipose tissue (VAT) undergoes substantial transformation characterized by a unique lipid-rich hypoxic AT microenvironment which plays a crucial role in VAT dysfunction, leading to insulin resistance (IR) and type 2 diabetes. Here, we demonstrate that obese AT microenvironment triggers the release of miR-210-3p microRNA-loaded extracellular vesicles from adipose tissue macrophages, which disseminate miR-210-3p to neighboring adipocytes, skeletal muscle cells, and hepatocytes through paracrine and endocrine actions, thereby influencing insulin sensitivity. Moreover, EVs collected from Dicer-silenced miR-210-3p-overexpressed bone marrow-derived macrophages induce glucose intolerance and IR in lean mice. Mechanistically, miR-210-3p interacts with the 3'-UTR of GLUT4 mRNA and silences its expression, compromising cellular glucose uptake and insulin sensitivity. Therapeutic inhibition of miR-210-3p in VAT notably rescues high-fat diet-fed mice from obesity-induced systemic glucose intolerance. Thus, targeting adipose tissue macrophage-specific miR-210-3p during obesity could be a promising strategy for managing IR and type 2 diabetes.
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Transportador de Glucose Tipo 4 , Resistência à Insulina , Macrófagos , MicroRNAs , Obesidade , MicroRNAs/genética , MicroRNAs/metabolismo , Animais , Obesidade/metabolismo , Obesidade/genética , Obesidade/patologia , Macrófagos/metabolismo , Camundongos , Transportador de Glucose Tipo 4/metabolismo , Transportador de Glucose Tipo 4/genética , Masculino , Camundongos Endogâmicos C57BL , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Humanos , Dieta Hiperlipídica/efeitos adversos , Intolerância à Glucose/metabolismo , Intolerância à Glucose/genética , Intolerância à Glucose/patologia , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/patologiaRESUMO
We study current-induced switching of the Néel vector in CoO/Pt bilayers to understand the underlying antiferromagnetic switching mechanism. Surprisingly, we find that for ultrathin CoO/Pt bilayers electrical pulses along the same path can lead to an increase or decrease of the spin Hall magnetoresistance signal, depending on the current density of the pulse. By comparing these results to XMLD-PEEM imaging of the antiferromagnetic domain structure before and after the application of current pulses, we reveal the details of the reorientation of the Néel vector in ultrathin CoO(4 nm). This allows us to understand how opposite resistance changes can result from a thermomagnetoelastic switching mechanism. Importantly, our spatially resolved imaging shows that regions where the current pulses are applied and regions further away exhibit different switched spin structures, which can be explained by a spin-orbit torque-based switching mechanism that can dominate in very thin films.
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Bacterial promoters play a crucial role in gene expression by serving as docking sites for the transcription initiation machinery. However, accurately identifying promoter regions in bacterial genomes remains a challenge due to their diverse architecture and variations. In this study, we propose MLDSPP (Machine Learning and Duplex Stability based Promoter prediction in Prokaryotes), a machine learning-based promoter prediction tool, to comprehensively screen bacterial promoter regions in 12 diverse genomes. We leveraged biologically relevant and informative DNA structural properties, such as DNA duplex stability and base stacking, and state-of-the-art machine learning (ML) strategies to gain insights into promoter characteristics. We evaluated several machine learning models, including Support Vector Machines, Random Forests, and XGBoost, and assessed their performance using accuracy, precision, recall, specificity, F1 score, and MCC metrics. Our findings reveal that XGBoost outperformed other models and current state-of-the-art promoter prediction tools, namely Sigma70pred and iPromoter2L, achieving F1-scores >95% in most systems. Significantly, the use of one-hot encoding for representing nucleotide sequences complements these structural features, enhancing our XGBoost model's predictive capabilities. To address the challenge of model interpretability, we incorporated explainable AI techniques using Shapley values. This enhancement allows for a better understanding and interpretation of the predictions of our model. In conclusion, our study presents MLDSPP as a novel, generic tool for predicting promoter regions in bacteria, utilizing original downstream sequences as nonpromoter controls. This tool has the potential to significantly advance the field of bacterial genomics and contribute to our understanding of gene regulation in diverse bacterial systems.
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Comportamento de Utilização de Ferramentas , Bactérias/genética , DNA/genética , Aprendizado de Máquina , Regiões Promotoras GenéticasRESUMO
Recent studies have highlighted the deleterious contributions of B cells to post-stroke recovery and cognitive decline. Different B cell subsets have been proposed on the basis of expression levels of transcription factors (e.g., T-bet) as well as specific surface proteins. CD11b (α-chain of integrin) is expressed by several immune cell types and is involved in regulation of cell motility, phagocytosis, and other essential functions of host immunity. Although B cells express CD11b, the CD11bhigh subset of B cells has not been well characterized, especially in immune dysregulation seen with aging and after stroke. Here, we investigate the role of CD11bhigh B cells in immune responses after stroke in young and aged mice. We evaluated the ability of CD11bhigh B cells to influence pro- and anti-inflammatory phenotypes of young and aged microglia (MG). We hypothesized that CD11bhigh B cells accumulate in the brain and contribute to neuroinflammation in aging and after stroke. We found that CD11bhigh B cells are a heterogeneous subpopulation of B cells predominantly present in naive aged mice. Their frequency increases in the brain after stroke in young and aged mice. Importantly, CD11bhigh B cells regulate MG phenotype and increase MG phagocytosis in both ex vivo and in vivo settings, likely by production of regulatory cytokines (e.g., TNF-α). As both APCs and adaptive immune cells with long-term memory function, B cells are uniquely positioned to regulate acute and chronic phases of the post-stroke immune response, and their influence is subset specific.
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Microglia , Acidente Vascular Cerebral , Animais , Linfócitos B/metabolismo , Antígeno CD11b/metabolismo , Contagem de Células , Citocinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Acidente Vascular Cerebral/metabolismoRESUMO
In the field of aquaculture, bacterial pathogens pose significant challenges to fish health and production. Advancements in genomic technologies have revolutionized our understanding of bacterial fish pathogens and their interactions with their host species. This review explores the application of genomic approaches in the identification, classification, and characterization of bacterial fish pathogens. Through an extensive analysis of the literature, we have compiled valuable data on 79 bacterial fish pathogens spanning 13 different phyla, encompassing their whole genome sequences. By leveraging high-throughput sequencing techniques, researchers have gained valuable insights into the genomic makeup of these pathogens, enabling a deeper understanding of their virulence factors and mechanisms of host interaction. Furthermore, genomic approaches have facilitated the discovery of potential vaccine and drug targets, opening up new avenues for the development of effective interventions against fish pathogens. Additionally, the utilization of genomics in fish disease resistance and control in aquaculture has shown promising results, enabling the identification of genetic markers associated with disease resistance traits. This review highlights the significant contributions of genomics to the field of fish pathogen research and underscores its potential for improving disease management strategies and enhancing the sustainability of aquaculture practices.
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Resistência à Doença , Genômica , Animais , Resistência à Doença/genética , Aquicultura , Gerenciamento Clínico , Sistemas de Liberação de Medicamentos , Peixes/genéticaRESUMO
BACKGROUND: Recent 23Na-MRI reports show higher salt deposition in malignant breast tissue than in surrounding normal tissue. The effect of high salt on cancer progression remains controversial. Here, we investigated the direct effect of high salt on breast cancer progression in vitro. METHODS: Here, the impact of high salt on apoptosis, proliferation, cell cycle, adhesion, and migration of MDA-MB-231 and MCF-7 cells was studied using MTT, scratch, and clonogenic assays, as well as RT-PCR and flow cytometry. Gene expression was analyzed using Real-Time PCR and western blotting. The effect of high salt on global transcriptomics changes in MDA MB-231 cells was studied using RNA-sequencing analysis. RESULTS: Flow cytometry with Annexin V and CFSE revealed that high salt-induced dose-dependent apoptosis and inhibited proliferation. High salt-induced cell cycle arrest at the G1/S phase of the cell cycle. p-MDM2 is known to suppress p53, which plays a crucial role in regulating apoptosis and cell cycle arrest under cellular stress conditions. High salt treatment led to decreased p-MDM2 and increased p53 expression, suggesting that high salt induces apoptosis through p53 stabilization. decreased p-MDM2 and increased p53 expression. High salt also reduced migration and adhesion of cells in a dose-dependent manner suggesting its inhibitory effect on metastatic properties as evident from wound healing assay. RNA sequencing analysis revealed overexpression of tumor suppressor genes and genes associated with anti-tumor activity (PCDHGA11, EIF3CL, RAVER1, TNFSF15, RANBP3L) and under-expression of genes involved in cancer-promoting activity (MT1X, CLDN14, CSF-2). CONCLUSION: Our results unequivocally demonstrate the anti-tumor efficacy of high salt against breast cancer cells, suggesting its potential as a therapeutic strategy in cancer treatment.
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Apoptose , Neoplasias da Mama , Movimento Celular , Proliferação de Células , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células MCF-7 , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Antineoplásicos/farmacologia , Cloreto de Sódio/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacosRESUMO
Mammalian cells are surrounded by neighbouring cells and extracellular matrix (ECM), which provide cells with structural support and mechanical cues that influence diverse biological processes1. The Hippo pathway effectors YAP (also known as YAP1) and TAZ (also known as WWTR1) are regulated by mechanical cues and mediate cellular responses to ECM stiffness2,3. Here we identified the Ras-related GTPase RAP2 as a key intracellular signal transducer that relays ECM rigidity signals to control mechanosensitive cellular activities through YAP and TAZ. RAP2 is activated by low ECM stiffness, and deletion of RAP2 blocks the regulation of YAP and TAZ by stiffness signals and promotes aberrant cell growth. Mechanistically, matrix stiffness acts through phospholipase Cγ1 (PLCγ1) to influence levels of phosphatidylinositol 4,5-bisphosphate and phosphatidic acid, which activates RAP2 through PDZGEF1 and PDZGEF2 (also known as RAPGEF2 and RAPGEF6). At low stiffness, active RAP2 binds to and stimulates MAP4K4, MAP4K6, MAP4K7 and ARHGAP29, resulting in activation of LATS1 and LATS2 and inhibition of YAP and TAZ. RAP2, YAP and TAZ have pivotal roles in mechanoregulated transcription, as deletion of YAP and TAZ abolishes the ECM stiffness-responsive transcriptome. Our findings show that RAP2 is a molecular switch in mechanotransduction, thereby defining a mechanosignalling pathway from ECM stiffness to the nucleus.
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Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Proteínas rap de Ligação ao GTP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Transformação Celular Neoplásica , Matriz Extracelular/química , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Feminino , Proteínas Ativadoras de GTPase/metabolismo , Quinases do Centro Germinativo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células HEK293 , Via de Sinalização Hippo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Proteínas do Tecido Nervoso/metabolismo , Fosfolipase C gama/metabolismo , Fosfoproteínas/metabolismo , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Transcriptoma , Proteínas de Sinalização YAP , Proteínas rap de Ligação ao GTP/genéticaRESUMO
BACKGROUND: Laparoscopic Heller's myotomy (LHM) is an established treatment for achalasia cardia. Anti-reflux procedures (ARP) are recommended with LHM to reduce the post-operative reflux though the optimal anti-reflux procedure is still debatable. This study reports on the long-term outcomes of LHM with Angle-of-His accentuation (AOH) in patients of achalasia cardia. METHODS: One hundred thirty-six patients of achalasia cardia undergoing LHM with AOH between January 2010 to October 2021 with a minimum follow-up of one year were evaluated for symptomatic outcomes using Eckardt score (ES), DeMeester heartburn (DMH) score and achalasia disease specific quality of life (A-DsQoL) questionnaire. Upper gastrointestinal endoscopy, high resolution manometry (HRM) and timed barium esophagogram (TBE) were performed when feasible and rates of esophagitis and improvement in HRM and TBE parameters evaluated. Time dependent rates of success were calculated with respect to improvement in ES and dysphagia-, regurgitation- and heartburn-free survival using Kaplan-Meier analysis. RESULTS: At a median follow-up of 65.5 months, the overall success (ES ≤ 3) was 94.1%. There was statistically significant improvement in ES, heartburn score and A-DsQoL score (p < 0.00001, p = 0.002 and p < 0.00001). Significant heartburn (score ≥ 2) was seen in 12.5% subjects with 9.5% patients reporting frequent PPI use (> 3 days per week). LA-B and above esophagitis was seen in 12.7%. HRM and TBE parameters also showed a significant improvement as compared to pre-operative values (IRP: p < 0.0001, column height: p < 0.0001, column width: p = 0.0002). Kaplan-Meier analysis showed dysphagia, regurgitation, and heartburn free survival of 75%, 96.2% and 72.3% respectively at 10 years. CONCLUSIONS: LHM with AOH gives a lasting relief of symptoms in patients of achalasia cardia with heartburn rates similar to that reported in studies using Dor's or Toupet's fundoplication with LHM. Hence, LHM with AOH may be a preferred choice in patients of achalasia cardia given the simplicity of the procedure.
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Transtornos de Deglutição , Acalasia Esofágica , Esofagite , Miotomia de Heller , Laparoscopia , Humanos , Acalasia Esofágica/cirurgia , Acalasia Esofágica/diagnóstico , Azia/cirurgia , Transtornos de Deglutição/etiologia , Miotomia de Heller/métodos , Cárdia/cirurgia , Qualidade de Vida , Laparoscopia/métodos , Esofagite/etiologia , Resultado do TratamentoRESUMO
Adsorbed molecules on a catalyst almost always arrange themselves in a manner that is far from perfectly random, which gives rise to spatial correlations. These correlations are a result of the interactions between the adsorbed species (adspecies) as well as elementary processes such as diffusion and reaction events that shape the adspecies arrangements. Despite their importance, spatial correlations are usually ignored while writing species balance equations for the modeling of heterogeneous catalytic systems. Recently, we have introduced a probabilistic microkinetic modeling (p-MKM) framework that aims at incorporating spatial correlations in the form of a short-ranged order (SRO) parameter into species balance equations. Here, we extend the approach to catalytic systems of higher complexity, namely, longer interactions and multiple species. This is made possible by including multiple pair probabilities in the p-MKM model for the first time. The interplay between different SRO parameters is probed. An important consideration is how many pair probabilities should be included to capture the underlying complexity with sufficient accuracy.
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Photosystem II (PSII) is an intrinsic membrane protein complex that functions as a light-driven water:plastoquinone oxidoreductase in oxygenic photosynthesis. Electron transport in PSII is associated with formation of reactive oxygen species (ROS) responsible for oxidative modifications of PSII proteins. In this study, oxidative modifications of the D1 and D2 proteins by the superoxide anion (O2â¢-) and the hydroxyl (HOâ¢) radicals were studied in WT and a tocopherol cyclase (vte1) mutant, which is deficient in the lipid-soluble antioxidant α-tocopherol. In the absence of this antioxidant, high-resolution tandem mass spectrometry was used to identify oxidation of D1:130E to hydroxyglutamic acid by O2â¢- at the PheoD1 site. Additionally, D1:246Y was modified to either tyrosine hydroperoxide or dihydroxyphenylalanine by O2â¢- and HOâ¢, respectively, in the vicinity of the nonheme iron. We propose that α-tocopherol is localized near PheoD1 and the nonheme iron, with its chromanol head exposed to the lipid-water interface. This helps to prevent oxidative modification of the amino acid's hydrogen that is bonded to PheoD1 and the nonheme iron (via bicarbonate), and thus protects electron transport in PSII from ROS damage.
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Aminoácidos/química , Arabidopsis/enzimologia , Complexo de Proteína do Fotossistema II/química , Superóxidos/química , Tilacoides/enzimologia , alfa-Tocoferol/química , Aminoácidos/metabolismo , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Sítios de Ligação , Radical Hidroxila/química , Radical Hidroxila/metabolismo , Transferases Intramoleculares/química , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Ferro/química , Ferro/metabolismo , Luz , Modelos Moleculares , Mutação , Oxirredução , Oxigênio/química , Oxigênio/metabolismo , Fotossíntese/fisiologia , Fotossíntese/efeitos da radiação , Complexo de Proteína do Fotossistema II/genética , Complexo de Proteína do Fotossistema II/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Superóxidos/metabolismo , Termodinâmica , Thermosynechococcus/enzimologia , Thermosynechococcus/genética , Thermosynechococcus/efeitos da radiação , Tilacoides/genética , Tilacoides/efeitos da radiação , alfa-Tocoferol/metabolismoRESUMO
Ralstonia solanacearum, the bacterium that causes bacterial wilt, is a destructive phytopathogen that can infect over 450 different plant species. Several agriculturally significant crop plants, including eggplant, tomato, pepper, potato, and ginger, are highly susceptible to this plant disease, which has a global impact on crop quality and yield. There is currently no known preventive method that works well for bacterial wilt. Bacteria use two-component systems (TCSs) to sense their environment constantly and react appropriately. This is achieved by an extracellular sensor kinase (SK) capable of sensing a suitable signal and a cytoplasmic response regulator (RR) which gives a downstream response. Moreover, our investigation revealed that R. solanacearum GMI1000 possesses a substantial count of TCSs, specifically comprising 36 RRs and 27 SKs. While TCSs are known targets for various human pathogenic bacteria, such as Salmonella, the role of TCSs in R. solanacearum remains largely unexplored in this context. Notably, numerous inhibitors targeting TCSs have been identified, including GHL (Gyrase, Hsp, and MutL) compounds, Walk inhibitors, and anti-TCS medications like Radicicol. Consequently, the investigation into the involvement of TCSs in virulence and pathogenesis has gained traction; however, further research is imperative to ascertain whether TCSs could potentially supplant conventional anti-wilt therapies. This review delves into the prospective utilization of TCSs as an alternative anti-wilt therapy, focusing on the lethal phytopathogen R. solanacearum.
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Ralstonia solanacearum , Humanos , Estudos Prospectivos , Bactérias , Citoplasma , CitosolRESUMO
INTRODUCTION: Post-operative analgesia is an important component of patient satisfaction and early discharge from the hospital. A variety of modalities have been tested and are still evolving. The present study is one such evaluation of a novel technique of laparoscopy-guided transverse abdominis plane (LTAP) block for post-operative analgesia in laparoscopic cholecystectomy. PATIENTS AND METHODS: A prospective randomised control trial was conducted to verify the effectiveness of LTAP block over port site local anaesthesia infiltration (PSLAI) for post-operative analgesia in patients undergoing laparoscopic cholecystectomy. This study was done over a period of 18 months in a tertiary hospital. A total of 84 patients were recruited and were divided equally into two groups (LTAP and PSLAI). RESULTS: There was no statistical difference between the two groups with respect to gender distribution, comorbidities, number of gallstones, duration of symptoms and surgery time. The rescue dose of diclofenac requirement was less for the LTAP group in comparison to the PSLAI group. No difference was observed in the pain score at 1st h. However, LTAP proved efficient later in the post-operative course (6 h, 24 h and at discharge). There was significant a difference in the pain scores between the two groups, favouring the LTAP group. Hospital stay in the LTAP group was less in comparison to the PSLAI group. CONCLUSION: LTAP block is an effective method of post-operative analgesia. It impacts analgesia to the whole anterior abdominal wall for a prolonged period when compared to the PSLAI without adding any extra procedural time.
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BACKGROUND: Hemoglobin concentration and diffusion-weighted imaging (DWI) ischemic lesions are separately known to be associated with poor intracerebral hemorrhage (ICH) outcomes. While hemoglobin concentrations have known relationships with ischemic stroke, it is unclear whether hemoglobin concentration is associated with DWI ischemic lesions after ICH. We sought to investigate the hypothesis that hemoglobin concentrations would associate with DWI lesions after ICH and further investigated their relationships with clinical outcomes. METHODS: Supratentorial ICH patients enrolled between 2010 and 2016 to a prospective, multicenter, observational cohort study (ERICH study [Ethnic/Racial Variations of Intracerebral Hemorrhage]) were assessed. Patients from this study with baseline, admission hemoglobin, and hospitalization magnetic resonance imaging were analyzed. Hemoglobin was examined as the primary exposure variable defined as a continuous variable (g/dL). Magnetic resonance imaging DWI ischemic lesion presence was assessed as the primary radiographic outcome. Primary analyses assessed relationships of hemoglobin with DWI lesions. Secondary analyses assessed relationships of DWI lesions with poor 3-month outcomes (modified Rankin Scale score, 4-6). These analyses were performed using separate multivariable logistic regression models adjusting for relevant covariates. RESULTS: Of 917 patients with ICH analyzed, mean baseline hemoglobin was 13.8 g/dL (±1.9), 60% were deep ICH, and DWI lesions were identified in 27% of the cohort. In our primary analyses, increased hemoglobin, defined as a continuous variable, was associated with DWI lesions (adjusted odds ratio, 1.21 per 1 g/dL change in hemoglobin [95% CI, 1.07-1.37]) after adjusting for sex, race, ICH severity, time to magnetic resonance imaging, and acute blood pressure change. In secondary analyses, DWI lesions were associated with poor 3-month outcomes (adjusted odds ratio, 1.83 [95% CI, 1.24-2.69]) after adjusting for similar covariates. CONCLUSIONS: We identified novel relationships between higher baseline hemoglobin concentrations and DWI ischemic lesions in patients with ICH. Further studies are required to clarify the role of hemoglobin concentration on both cerebral small vessel disease pathophysiology and ICH outcomes.
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Hemorragia Cerebral , Imageamento por Ressonância Magnética , Humanos , Estudos Prospectivos , Hemorragia Cerebral/complicações , Imagem de Difusão por Ressonância Magnética/métodos , HemoglobinasRESUMO
OBJECTIVES: Low hemoglobin concentration impairs clinical hemostasis across several diseases. It is unclear whether hemoglobin impacts laboratory functional coagulation assessments. We evaluated the relationship of hemoglobin concentration on viscoelastic hemostatic assays in intracerebral hemorrhage (ICH) and perioperative patients admitted to an ICU. DESIGN: Observational cohort study and separate in vitro laboratory study. SETTING: Multicenter tertiary referral ICUs. PATIENTS: Two acute ICH cohorts receiving distinct testing modalities: rotational thromboelastometry (ROTEM) and thromboelastography (TEG), and a third surgical ICU cohort receiving ROTEM were evaluated to assess the generalizability of findings across disease processes and testing platforms. A separate in vitro ROTEM laboratory study was performed utilizing ICH patient blood samples. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Relationships between baseline hemoglobin and ROTEM/TEG results were separately assessed across patient cohorts using Spearman correlations and linear regression models. A separate in vitro study assessed ROTEM tracing changes after serial hemoglobin modifications from ICH patient blood samples. In both our ROTEM (n = 34) and TEG (n = 239) ICH cohorts, hemoglobin concentrations directly correlated with coagulation kinetics (ROTEM r: 0.46; p = 0.01; TEG r: 0.49; p < 0.0001) and inversely correlated with clot strength (ROTEM r: -0.52, p = 0.002; TEG r: -0.40, p < 0.0001). Similar relationships were identified in perioperative ICU admitted patients (n = 121). We continued to identify these relationships in linear regression models. When manipulating ICH patient blood samples to achieve lower hemoglobin concentrations in vitro, we similarly identified that lower hemoglobin concentrations resulted in progressively faster coagulation kinetics and greater clot strength on ROTEM tracings. CONCLUSIONS: Lower hemoglobin concentrations have a consistent, measurable impact on ROTEM/TEG testing in ICU admitted patients, which appear to be artifactual. It is possible that patients with low hemoglobin may appear to have normal viscoelastic parameters when, in fact, they have a mild hypocoagulable state. Further work is required to determine if these tests should be corrected for a patient's hemoglobin concentration.
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Transtornos da Coagulação Sanguínea , Hemorragia Cerebral , Hemoglobinas , Hemostasia , Hemostáticos , Humanos , Transtornos da Coagulação Sanguínea/diagnóstico , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/terapia , Hemoglobinas/análise , Tromboelastografia/métodos , Unidades de Terapia IntensivaRESUMO
Portlandite (calcium hydroxide: CH: Ca(OH)2) suspensions aggregate spontaneously and form percolated fractal aggregate networks when dispersed in water. Consequently, the viscosity and yield stress of portlandite suspensions diverge at low particle loadings, adversely affecting their processability. Even though polycarboxylate ether (PCE)-based comb polyelectrolytes are routinely used to alter the particle dispersion state, water demand, and rheology of similar suspensions (e.g., ordinary portland cement suspensions) that feature a high pH and high ionic strength, their use to control portlandite suspension rheology has not been elucidated. This study combines adsorption isotherms and rheological measurements to elucidate the role of PCE composition (i.e., charge density, side chain length, and grafting density) in controlling the extent of PCE adsorption, particle flocculation, suspension yield stress, and thermal response of portlandite suspensions. We show that longer side-chain PCEs are more effective in affecting suspension viscosity and yield stress, in spite of their lower adsorption saturation limit and fractional adsorption. The superior steric hindrance induced by the longer side chain PCEs results in better efficacy in mitigating particle aggregation even at low dosages. However, when dosed at optimal dosages (i.e., a dosage that induces a dynamically equilibrated dispersion state of particle aggregates), different PCE-dosed portlandite suspensions exhibit identical fractal structuring and rheological behavior regardless of the side chain length. Furthermore, it is shown that the unusual evolution of the rheological response of portlandite suspensions with temperature can be tailored by adjusting the PCE dosage. The ability of PCEs to modulate the rheology of aggregating charged particle suspensions can be generally extended to any colloidal suspension with a strong screening of repulsive electrostatic interactions.
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We present a probabilistic microkinetic modeling (MKM) framework that incorporates the short-ranged order (SRO) evolution for adsorbed species (adspecies) on a catalyst surface. The resulting model consists of a system of ordinary differential equations. Adsorbate-adsorbate interactions, surface diffusion, adsorption, desorption, and catalytic reaction processes are included. Assuming that the adspecies ordering/arrangement is accurately described by the SRO parameters, we employ the reverse Monte Carlo (RMC) method to extract the relevant local environment probability distributions and pass them to the MKM. The reaction kinetics is faithfully captured as accurately as the kinetic Monte Carlo (KMC) method but with a computational time requirement of few seconds on a standard desktop computer. KMC, on the other hand, can require several days for the examples discussed. The framework presented here is expected to provide the basis for wider application of the RMC-MKM approach to problems in computational catalysis, electrocatalysis, and material science.
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Intussusception in adults represents 1% of bowel obstructions and up to 0.02% of all hospital admissions. Amongst these, colo-colic intussusception of the descending colon forms the rarest of causes due to the fixed nature of the descending colon. Most of adult intussusceptions follow a lead point and are commonly due to colonic malignancy which may get missed on pre-operative evaluation. Surgery is usually warranted as these patients are usually symptomatic and at risk of vascular compromise, leading to perforations and obscure malignancies. We present a case of laparoscopic limited hemicolectomy and primary anastomosis in a middle-aged male who presented with colo-colic intussusception, which appeared to be following a malignant mass on imaging and lipoma on colonoscopic biopsy done twice. Keeping in mind the possibility of a malignant lead point, no attempt was made to reduce the intussusception and a vessel first approach with 5 cm margin on either side was performed.
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BACKGROUND: Archaea are a vast and unexplored domain. Bioinformatic techniques might enlighten the path to a higher quality genome annotation in varied organisms. Promoter sequences of archaea have the action of a plethora of proteins upon it. The conservation found in a structural level of the binding site of proteins such as TBP, TFB, and TFE aids RNAP-DNA stabilization and makes the archaeal promoter prone to be explored by statistical and machine learning techniques. RESULTS AND DISCUSSIONS: In this study, experimentally verified promoter sequences of the organisms Haloferax volcanii, Sulfolobus solfataricus, and Thermococcus kodakarensis were converted into DNA duplex stability attributes (i.e. numerical variables) and were classified through Artificial Neural Networks and an in-house statistical method of classification, being tested with three forms of controls. The recognition of these promoters enabled its use to validate unannotated promoter sequences in other organisms. As a result, the binding site of basal transcription factors was located through a DNA duplex stability codification. Additionally, the classification presented satisfactory results (above 90%) among varied levels of control. CONCLUDING REMARKS: The classification models were employed to perform genomic annotation into the archaea Aciduliprofundum boonei and Thermofilum pendens, from which potential promoters have been identified and uploaded into public repositories.