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1.
Mol Cell ; 77(1): 17-25.e5, 2020 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-31704183

RESUMEN

Structural and biochemical studies have revealed the basic principles of how the replisome duplicates genomic DNA, but little is known about its dynamics during DNA replication. We reconstitute the 34 proteins needed to form the S. cerevisiae replisome and show how changing local concentrations of the key DNA polymerases tunes the ability of the complex to efficiently recycle these proteins or to dynamically exchange them. Particularly, we demonstrate redundancy of the Pol α-primase DNA polymerase activity in replication and show that Pol α-primase and the lagging-strand Pol δ can be re-used within the replisome to support the synthesis of large numbers of Okazaki fragments. This unexpected malleability of the replisome might allow it to deal with barriers and resource challenges during replication of large genomes.


Asunto(s)
ADN Polimerasa III/genética , Replicación del ADN/genética , ADN/genética , Células Eucariotas/fisiología , ADN Polimerasa I/genética , ADN Primasa/genética , Saccharomyces cerevisiae/genética
2.
Nucleic Acids Res ; 51(11): 5714-5742, 2023 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-37125644

RESUMEN

The bacterial RecF, RecO, and RecR proteins are an epistasis group involved in loading RecA protein into post-replication gaps. However, the targeting mechanism that brings these proteins to appropriate gaps is unclear. Here, we propose that targeting may involve a direct interaction between RecF and DnaN. In vivo, RecF is commonly found at the replication fork. Over-expression of RecF, but not RecO or a RecF ATPase mutant, is extremely toxic to cells. We provide evidence that the molecular basis of the toxicity lies in replisome destabilization. RecF over-expression leads to loss of genomic replisomes, increased recombination associated with post-replication gaps, increased plasmid loss, and SOS induction. Using three different methods, we document direct interactions of RecF with the DnaN ß-clamp and DnaG primase that may underlie the replisome effects. In a single-molecule rolling-circle replication system in vitro, physiological levels of RecF protein trigger post-replication gap formation. We suggest that the RecF interactions, particularly with DnaN, reflect a functional link between post-replication gap creation and gap processing by RecA. RecF's varied interactions may begin to explain how the RecFOR system is targeted to rare lesion-containing post-replication gaps, avoiding the potentially deleterious RecA loading onto thousands of other gaps created during replication.


Asunto(s)
Proteínas de Unión al ADN , Proteínas de Escherichia coli , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Reparación del ADN , Replicación del ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo
3.
J Clin Microbiol ; 62(1): e0054623, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38051069

RESUMEN

The Selux Next-Generation Phenotyping (NGP) system (Charlestown, MA) is a new antimicrobial susceptibility testing system that utilizes two sequential assays performed on all wells of doubling dilution series to determine MICs. A multicenter evaluation of the performance of the Selux NGP system compared with reference broth microdilution was conducted following FDA recommendations and using FDA-defined breakpoints. A total of 2,488 clinical and challenge isolates were included; gram-negative isolates were tested against 24 antimicrobials, and gram-positive isolates were tested against 15 antimicrobials. Data is provided for all organism-antimicrobial combinations evaluated, including those that did and did not meet FDA performance requirements. Overall very major error and major error rates were less than 1% (31/3,805 and 107/15,606, respectively), essential agreement and categorical agreement were >95%, reproducibility was ≥95%, and the average time-to-result (from time of assay start to time of MIC result) was 5.65 hours.


Asunto(s)
Antibacterianos , Antiinfecciosos , Humanos , Antibacterianos/farmacología , Reproducibilidad de los Resultados , Pruebas de Sensibilidad Microbiana
4.
Inorg Chem ; 63(21): 9735-9752, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38728376

RESUMEN

A series of Ru(II) complexes incorporating two 4,4'-bis(trifluoromethyl)-2,2'-bipyridine (4,4'-btfmb) coligands and thienyl-appended imidazo[4,5-f][1,10]phenanthroline (IP-nT) ligands was characterized and assessed for phototherapy effects toward cancer cells. The [Ru(4,4'-btfmb)2(IP-nT)]2+ scaffold has greater overall redox activity compared to Ru(II) polypyridyl complexes such as [Ru(bpy)3]2+. Ru-1T-Ru-4T have additional oxidations due to the nT group and additional reductions due to the 4,4'-btfmb ligands. Ru-2T-Ru-4T also exhibit nT-based reductions. Ru-4T exhibits two oxidations and eight reductions within the potential window of -3 to +1.5 V. The lowest-lying triplets (T1) for Ru-0T-2T are metal-to-ligand charge-transfer (3MLCT) excited states with lifetimes around 1 µs, whereas T1 for Ru-3T-4T is longer-lived (∼20-24 µs) and of significant intraligand charge-transfer (3ILCT) character. Phototoxicity toward melanoma cells (SK-MEL-28) increases with n, with Ru-4T having a visible EC50 value as low as 9 nM and PI as large as 12,000. Ru-3T and Ru-4T retain some of this activity in hypoxia, where Ru-4T has a visible EC50 as low as 35 nM and PI as high as 2900. Activity over six biological replicates is consistent and within an order of magnitude. These results demonstrate the importance of lowest-lying 3ILCT states for phototoxicity and maintaining activity in hypoxia.

5.
Childs Nerv Syst ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39037454

RESUMEN

The primary purpose of this study was to enhance the understanding of diastematomyelia, with a particular focus on adult-onset cases, which are infrequent and not fully elucidated. Additionally, the study sought to analyse the clinical features, diagnostic characteristics, and surgical interventions employed to manage the condition. This retrospective case series aimed to investigate diastematomyelia, a rare congenital deformation affecting the spinal cord. The study included 16 patients diagnosed with diastematomyelia, consisting of 13 pediatric cases (mean age: 7.6 years, age range: 5 months to 13 years) and 3 adult cases (mean age: 36 years, age range: 26 to 48 years). Among the paediatric cases, 9 were females, and 4 were males, while the adult cohort comprised 2 males and 1 female. The study design involved a thorough review of medical records, imaging reports, and surgical outcomes without specific inclusion or exclusion criteria. Surgical intervention emerged as the primary treatment modality for all cases, except one. Following surgical intervention, significant improvements were observed in pain management, motor function, and bladder control. Furthermore, additional findings indicated the presence of Dural Ectasia and Vertebral segmentation defects among the study population. This retrospective case series sheds light on the clinical features and surgical outcomes of diastematomyelia in both pediatric and adult patients. The findings underscore the importance of surgical intervention in alleviating symptoms and enhancing motor coordination and bladder control.

6.
Clin J Sport Med ; 34(1): 25-29, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37462603

RESUMEN

OBJECTIVE: Previous research, including high-quality systematic reviews, has found that cervical injury, which often accompanies concussive head injury, can delay recovery from concussion. One pilot randomized controlled trial found that focused cervical assessment and appropriate intervention in children and young adults with persisting postconcussive symptoms (PPCS) improved recovery outcomes. Our sports medicine clinics adopted this approach early (within 2 weeks) in children (aged 10-18 years) after concussion. This study describes our clinical management protocol and compares the recovery trajectories in children after concussion with and without a concomitant cervical injury. DESIGN: Prospective cohort study. SETTING: Three university-affiliated outpatient sports medicine clinics from September 2016 to December 2019. PATIENTS: One-hundred thirty-four concussed children with cervical impairment (mean age 14.9 years, 65% male, and 6.2 days since concussion) were compared with 130 concussed children without cervical impairment (mean age 14.9 years, 57% male, and 6.0 days since concussion). INDEPENDENT VARIABLES: Examination findings related to the cervical spine (range of motion, cervical spasm, and cervical tenderness). MAIN OUTCOME MEASURES: Recovery time (measured in days), concussion symptom burden (Postconcussion Symptom Scale), and incidence of PPCS. RESULTS: Children with cervical impairment reported a higher initial symptom burden; however, there were no differences in recovery time (33.65 [28.20-39.09] days vs 35.98 [27.50-44.45] days, P = 0.651) or incidence of PPCS (40.0% vs 34.3%, P = 0.340). CONCLUSIONS: We conclude that within this pediatric population, early identification and management of cervical injuries concomitant with concussion may reduce the risk of delayed recovery.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , Síndrome Posconmocional , Adulto Joven , Humanos , Niño , Masculino , Adolescente , Femenino , Síndrome Posconmocional/diagnóstico , Síndrome Posconmocional/terapia , Síndrome Posconmocional/epidemiología , Estudios Prospectivos , Conmoción Encefálica/complicaciones , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/terapia , Medición de Riesgo , Traumatismos en Atletas/complicaciones , Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/terapia
7.
Blood ; 137(15): 2114-2124, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33662988

RESUMEN

Monoclonal immunoglobulin G (IgG) antibodies to CD44 (anti-CD44) are anti-inflammatory in numerous murine autoimmune models, but the mechanisms are poorly understood. Anti-CD44 anti-inflammatory activity shows complete therapeutic concordance with IV immunoglobulin (IVIg) in treating autoimmune disease models, making anti-CD44 a potential IVIg alternative. In murine immune thrombocytopenia (ITP), there is no mechanistic explanation for anti-CD44 activity, although anti-CD44 ameliorates disease similarly to IVIg. Here, we demonstrate a novel anti-inflammatory mechanism of anti-CD44 that explains disease amelioration by anti-CD44 in murine ITP. Macrophages treated with anti-CD44 in vitro had dramatically suppressed phagocytosis through FcγRs in 2 separate systems of IgG-opsonized platelets and erythrocytes. Phagocytosis inhibition by anti-CD44 was mediated by blockade of the FcγR IgG binding site without changing surface FcγR expression. Anti-CD44 of different subclasses revealed that FcγR blockade was specific to receptors that could be engaged by the respective anti-CD44 subclass, and Fc-deactivated anti-CD44 variants lost all FcγR-inhibiting activity. In vivo, anti-CD44 functioned analogously in the murine passive ITP model and protected mice from ITP when thrombocytopenia was induced through an FcγR that could be engaged by the CD44 antibody's subclass. Consistent with FcγR blockade, Fc-deactivated variants of anti-CD44 were completely unable to ameliorate ITP. Together, anti-CD44 inhibits macrophage FcγR function and ameliorates ITP consistent with an FcγR blockade mechanism. Anti-CD44 is a potential IVIg alternative and may be of particular benefit in ITP because of the significant role that FcγRs play in human ITP pathophysiology.


Asunto(s)
Receptores de Hialuranos/inmunología , Inmunoglobulina G/inmunología , Púrpura Trombocitopénica Idiopática/inmunología , Receptores de IgG/inmunología , Animales , Plaquetas/inmunología , Femenino , Humanos , Inflamación/inmunología , Ratones , Ratones Endogámicos C57BL , Fagocitosis , Células RAW 264.7
8.
Inorg Chem ; 62(51): 21181-21200, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38079387

RESUMEN

Ru(II) polypyridyl complexes have gained widespread attention as photosensitizers for photodynamic therapy (PDT). Herein, we systematically investigate a series of the type [Ru(phen)2(IP-nT)]2+, featuring 1,10-phenanthroline (phen) coligands and imidazo[4,5-f][1,10]phenanthroline ligands tethered to n = 0-4 thiophene rings (IP-nT). The complexes were characterized and investigated for their electrochemical, spectroscopic, and (photo)biological properties. The electrochemical oxidation of the nT unit shifted by -350 mV as n = 1 → 4 (+920 mV for Ru-1T, +570 mV for Ru-4T); nT reductions were observed in complexes Ru-3T (-2530 mV) and Ru-4T (-2300 mV). Singlet oxygen quantum yields ranged from 0.53 to 0.88, with Ru-3T and Ru-4T being equally efficient (∼0.88). Time-resolved absorption spectra of Ru-0T-1T were dominated by metal-to-ligand charge-transfer (3MLCT) states (τTA = 0.40-0.85 µs), but long-lived intraligand charge-transfer (3ILCT) states were observed in Ru-2T-4T (τTA = 25-148 µs). The 3ILCT energies of Ru-3T and Ru-4T were computed to be 1.6 and 1.4 eV, respectively. The phototherapeutic efficacy against melanoma cells (SK-MEL-28) under broad-band visible light (400-700 nm) increases as n = 0 → 4: Ru-0T was inactive up to 300 µM, Ru-1T-2T were moderately active (EC50 ∼ 600 nM, PI = 200), and Ru-3T (EC50 = 57 nM, PI > 1100) and Ru-4T (EC50 = 740 pM, PI = 114,000) were the most phototoxic. The activity diminishes with longer wavelengths of light and is completely suppressed for all complexes except Ru-3T and Ru-4T in hypoxia. Ru-4T is the more potent and robust PS in 1% O2 over seven biological replicates (avg EC50 = 1.3 µM, avg PI = 985). Ru-3T exhibited hypoxic activity in five of seven replicates, underscoring the need for biological replicates in compound evaluation. Singlet oxygen sensitization is likely responsible for phototoxic effects of the compounds in normoxia, but the presence of redox-active excited states may facilitate additional photoactive pathways for complexes with three or more thienyl groups. The 3ILCT state with its extended lifetime (30-40× longer than the 3MLCT state for Ru-3T and Ru-4T) implicates its predominant role in photocytotoxicity.


Asunto(s)
Fotoquimioterapia , Rutenio , Fenantrolinas/farmacología , Fenantrolinas/química , Oxígeno Singlete/química , Rutenio/farmacología , Rutenio/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Ligandos
9.
Cardiovasc Drugs Ther ; 37(6): 1167-1174, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35029799

RESUMEN

Cardiovascular risk has traditionally been defined by modifiable and non-modifiable risk factors, such as tobacco use, hyperlipidemia, and family history. However, chemicals and pollutants may also play a role in cardiovascular disease (CVD) risk. Arsenic is a naturally occurring element that is widely distributed in the Earth's crust. Inorganic arsenic (iAs) has been implicated in the pathogenesis of atherosclerosis, with chronic high-dose exposure to iAs (> 100 µg/L) being linked to CVD; however, whether low-to-moderate dose exposures of iAs (< 100 µg/L) are associated with the development of CVD is unclear. Due to limitations of the existing literature, it is difficult to define a threshold for iAs toxicity. Studies demonstrate that the effect of iAs on CVD is far more complex with influences from several factors, including diet, genetics, metabolism, and traditional risk factors such as hypertension and smoking. In this article, we review the existing data of low-to-moderate dose iAs exposure and its effect on CVD, along with highlighting the potential mechanisms of action.


Asunto(s)
Arsénico , Arsenicales , Aterosclerosis , Enfermedades Cardiovasculares , Humanos , Arsénico/toxicidad , Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Cardiovasculares/epidemiología , Factores de Riesgo , Aterosclerosis/inducido químicamente , Aterosclerosis/epidemiología
10.
Crit Care Nurs Q ; 46(2): 185-191, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36823745

RESUMEN

Critically ill patients are frequently transported between intensive care units (ICUs) and other sections of hospital, which may cause communication error. The aim of this study was to reduce errors while shifting and receiving of patients in and from the ICU. The present study was aimed to develop a Shifting and Receiving Performa for the patients admitted in the ICU of a tertiary care hospital. A multistage developmental study was conducted in ICUs. Eleven experts were selected by a purposive sampling technique, and the study was conducted in 4 phases. From the pool of items, a preliminary draft of the performa was prepared and the draft was given to experts to evaluate its content and face validity by conducting 2 Delphi rounds. The mean I-CVI of the shifting performa increased from 0.92 to 0.95, S-CVI/AVG exceeded from 0.88 to 0.96, and S-CVI/UA exceeded from 0.48 to 0.7 after Delphi round 2. In the case of the receiving performa, the mean I-CVI and S-CVI/AVG remained the same, that is, 0.98 in Delphi rounds 1 and 2. The mean S-CVI/UA also remained the same (ie, 0.9). The interrater reliability of the performa was found to be 0.95. Almost all the staff nurses found the performa to be beneficial, provided complete information, and reduced communication errors.


Asunto(s)
Comunicación , Unidades de Cuidados Intensivos , Humanos , Reproducibilidad de los Resultados , Técnica Delphi , Hospitalización , Encuestas y Cuestionarios
11.
Curr Issues Mol Biol ; 44(11): 5440-5473, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36354681

RESUMEN

Biomass yield and quality are the primary targets in forage crop improvement programs worldwide. Low-quality fodder reduces the quality of dairy products and affects cattle's health. In multipurpose crops, such as maize, sorghum, cowpea, alfalfa, and oat, a plethora of morphological and biochemical/nutritional quality studies have been conducted. However, the overall growth in fodder quality improvement is not on par with cereals or major food crops. The use of advanced technologies, such as multi-omics, has increased crop improvement programs manyfold. Traits such as stay-green, the number of tillers per plant, total biomass, and tolerance to biotic and/or abiotic stresses can be targeted in fodder crop improvement programs. Omic technologies, namely genomics, transcriptomics, proteomics, metabolomics, and phenomics, provide an efficient way to develop better cultivars. There is an abundance of scope for fodder quality improvement by improving the forage nutrition quality, edible quality, and digestibility. The present review includes a brief description of the established omics technologies for five major fodder crops, i.e., sorghum, cowpea, maize, oats, and alfalfa. Additionally, current improvements and future perspectives have been highlighted.

12.
Cardiovasc Drugs Ther ; 36(6): 1197-1220, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-34661802

RESUMEN

While there are physiologic differences in lipid metabolism in men and women, pharmacologic therapy is very effective in both with similar management strategies recommended in the current guidelines for the management of dyslipidemia. Despite similar guidelines for treatment, studies have shown that women have worse control of dyslipidemia than their male counterparts. This may stem from multiple contributing factors including underestimation of cardiovascular disease risk in women, decreased prescription and utilization of lipid-lowering therapies, decreased medication adherence, and higher risk of statin intolerance, all of which may contribute to lower attainment of lipid targets. Furthermore, heart disease is the leading cause of mortality in women, with heart disease noted an average of 7-10 years later than in men. This has historically led to the misperception that women are protected from heart disease and can be treated less aggressively. In fact, traditional risk factors for atherosclerotic cardiovascular disease often impact risk in women to a greater extent than they do in men. Unique risk factors such as pregnancy-related disorders also contribute to the level of risk and therefore warrant consideration in risk stratification. This review summarizes the efficacy of contemporary lipid-lowering therapies in women versus men and discusses the challenges that arise with lipid management in women along with potential ways to tackle these obstacles.


Asunto(s)
Enfermedades Cardiovasculares , Dislipidemias , Cardiopatías , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Humanos , Masculino , Femenino , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , Dislipidemias/diagnóstico , Dislipidemias/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Factores de Riesgo , Lípidos/uso terapéutico , Cardiopatías/tratamiento farmacológico
13.
Cardiovasc Drugs Ther ; 36(1): 173-186, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-32979175

RESUMEN

The widespread availability of highly effective antiretroviral therapies has reduced mortality from opportunistic infections in persons living with HIV (PLHIV), resulting in an increase in atherosclerotic cardiovascular disease (ASCVD) and other chronic illnesses (Samji et al. 2013). Although there has been a decline in morbidity and mortality from ASCVD in the past several decades, contemporary studies continue to report higher rates of cardiovascular events (Rosenson et al. 2020). HIV has been identified as a risk enhancer for ASCVD by multiple professional guideline writing committees (Grundy Scott et al. 2019, Mach et al. 2020); however, the utilization of cholesterol-lowering therapies in PLHIV remains low (Rosenson et al. 2018). Moreover, the use of statin therapy in PLHIV is complicated by drug-drug interactions that may either elevate or lower the blood statin concentrations resulting in increased toxicity or reduced efficacy respectively. Other comorbidities commonly associated with HIV present other challenges for the use of cholesterol-lowering therapies. This review will summarize the data on lipoprotein-associated ASCVD risk in PLHIV and discuss the challenges with effective treatment. Finally, we present a clinical algorithm to optimize cardiovascular risk reduction in this high-risk population.


Asunto(s)
Anticolesterolemiantes/farmacología , Enfermedades Cardiovasculares/prevención & control , Infecciones por VIH/complicaciones , Algoritmos , Fármacos Anti-VIH/administración & dosificación , Anticolesterolemiantes/administración & dosificación , Aterosclerosis/etiología , Aterosclerosis/prevención & control , Enfermedades Cardiovasculares/etiología , Colesterol/sangre , Interacciones Farmacológicas , Infecciones por VIH/tratamiento farmacológico , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología
14.
Appl Microbiol Biotechnol ; 106(17): 5359-5384, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35902410

RESUMEN

Microbial endophytes are ubiquitous and exist in each recognised plant species reported till date. Within the host plant, the entire community of microbes lives non-invasively within the active internal tissues without causing any harm to the plant. Endophytes interact with their host plant via metabolic communication enables them to generate signal molecules. In addition, the host plant's genetic recombination with endophytes helps them to imitate the host's physicochemical functions and develop identical active molecules. Therefore, when cultured separately, they begin producing the host plant phytochemicals. The fungal species Penicillium chrysogenum has portrayed the glory days of antibiotics with the invention of the antibiotic penicillin. Therefore, fungi have substantially supported social health by developing many bioactive molecules utilised as antioxidant, antibacterial, antiviral, immunomodulatory and anticancerous agents. But plant-related microbes have emanated as fountainheads of biologically functional compounds with higher levels of medicinal perspective in recent years. Researchers have been motivated by the endless need for potent drugs to investigate alternate ways to find new endophytes and bioactive molecules, which tend to be a probable aim for drug discovery. The current research trends with these promising endophytic organisms are reviewed in this review paper. KEY POINTS: • Identified 54 important bioactive compounds as agricultural relevance • Role of genome mining of endophytes and "Multi-Omics" tools in sustainable agriculture • A thorough description and graphical presentation of agricultural significance of plant endophytes.


Asunto(s)
Endófitos , Plantas , Agricultura , Antibacterianos , Seguridad Alimentaria , Hongos , Fitoquímicos
15.
N Engl J Med ; 389(18): 1709-1716, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37913509
16.
J Med Virol ; 93(4): 2406-2419, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33347622

RESUMEN

The analyses of 2325 severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) genomes revealed 107, 162, and 65 nucleotide substitutions in the coding region of SARS-CoV-2 from the three continents America, Europe, and Asia, respectively. Of these nucleotide substitutions 58, 94, and 37 were nonsynonymous types mostly present in the Nsp2, Nsp3, Spike, and ORF9. A continent-specific phylogram analyses clustered the SARS-CoV-2 in the different group based on the frequency of nucleotide substitutions. Detailed analyses about the continent-specific amino acid changes and their effectiveness by SNAP2 software was investigated. We found 11 common nonsynonymous mutations; among them, two novel effective mutations were identified in ORF9 (S194L and S202N). Intriguingly, ORF9 encodes nucleocapsid phosphoprotein possessing many effective mutations across continents and could be a potential candidate after the spike protein for studying the role of mutation in viral assembly and pathogenesis. Among the two forms of certain frequent mutation, one form is more prevalent in Europe continents (Nsp12:L314, Nsp13:P504, Nsp13:Y541, Spike:G614, and ORF8:L84) while other forms are more prevalent in American (Nsp12:P314, Nsp13:L504, Nsp13:C541, Spike:D614, and ORF8:L84) and Asian continents (Spike:D614), indicating the spatial and temporal dynamics of SARS-CoV-2. We identified highly conserved 38 regions and among these regions, 11 siRNAs were predicted on stringent criteria that can be used to suppress the expression of viral genes and the corresponding reduction of human viral infections. The present investigation provides information on different mutations and will pave the way for differentiating strains based on virulence and their use in the development of better antiviral therapy.


Asunto(s)
COVID-19/virología , Mutación , SARS-CoV-2/genética , Antivirales/farmacología , Asia/epidemiología , COVID-19/epidemiología , Proteínas de la Nucleocápside de Coronavirus/genética , Proteasas Similares a la Papaína de Coronavirus/genética , Europa (Continente)/epidemiología , Silenciador del Gen , Genes Virales , Genoma Viral , Humanos , Sistemas de Lectura Abierta , Fosfoproteínas/genética , Filogenia , ARN Interferente Pequeño/genética , SARS-CoV-2/clasificación , SARS-CoV-2/efectos de los fármacos , Proteínas no Estructurales Virales/genética , Proteínas Virales/genética , Tratamiento Farmacológico de COVID-19
17.
Exp Dermatol ; 30(3): 358-366, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33617094

RESUMEN

Advanced basal cell carcinomas (BCCs) are driven by the Hedgehog (HH) pathway and often possess inherent resistance to SMO inhibitors. Identifying and targeting pathways that bypass SMO could provide alternative treatments for patients with advanced or metastatic BCC. Here, we use a combination of RNA-sequencing analysis of advanced human BCC tumor-normal pairs and immunostaining of human and mouse BCC samples to identify an MTOR expression signature in BCC. Pharmacological inhibition of MTOR activity in BCC cells significantly reduces cell proliferation without affecting HH signalling. Similarly, treatment of the Ptch1 fl/fl ; Gli1-CreERT2 mouse BCC tumor model with everolimus reduces tumor growth. aPKC, a downstream target of MTOR, shows reduced activity, suggesting that MTOR promotes tumor growth by activating aPKC and demonstrating that suppressing MTOR could be a promising target for BCC patients.


Asunto(s)
Carcinoma Basocelular/genética , Carcinoma Basocelular/metabolismo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Serina-Treonina Quinasas TOR , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Carcinoma Basocelular/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Everolimus/farmacología , Everolimus/uso terapéutico , Proteínas Hedgehog/metabolismo , Humanos , Imidazoles/farmacología , Inmunohistoquímica , Ratones , Receptor Patched-1/genética , Proteína Quinasa C/metabolismo , Análisis de Secuencia de ARN , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Triazinas/farmacología , Proteína con Dedos de Zinc GLI1/genética
18.
Arterioscler Thromb Vasc Biol ; 40(5): 1413-1419, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32078340

RESUMEN

OBJECTIVE: Warfarin is associated with medial arterial calcification in humans, but the magnitude and specificity of this effect and the role of other risk factors are unknown. Using serial mammograms, progression of arterial calcification was compared in women receiving no anticoagulants, warfarin, or other anticoagulants, and before, during, and after warfarin use. Approach and Results: Warfarin users with mammograms were identified by computerized searches of medical records that included renal function and diabetes mellitus. Lengths of calcified arterial segments were measured, with progression expressed as millimeters per breast per year and presented as medians and interquartile range (IQR). In women with normal renal function (estimated glomerular filtration rate >60 mL/minute per 1.73 m2), progression was 3.9-fold greater in warfarin users: 9.9 (3.8-16) versus 2.5 (0.7-6.7) in controls, P=0.0003, but not increased in users of other anticoagulants. In longitudinal analyses, progression increased from 2.1 (IQR, 0.3-3.9) to 13.8 (IQR, 7.8-38.7; P=0.011) after starting warfarin (n=11) and decreased from 8.8 (IQR, 1.1-10) to 1.9 (IQR, -10 to 6.7; P=0.024) after discontinuation of warfarin (n=13). Progression of calcification was similar in warfarin users with chronic kidney disease (7.3 [IQR, 3.6-17], n=29) but markedly accelerated in warfarin users with end-stage renal disease (47 [IQR, 31-183], n=11; P=0.0002). Progression was similar in diabetic and nondiabetic warfarin users (10.1 [IQR, 3.8-24] versus 7.8 [IQR, 3.6-15]) and did not correlate with age (r=0.09) or duration of warfarin therapy (r=0.12). CONCLUSIONS: Warfarin significantly accelerates medial arterial calcification in humans. This effect is markedly augmented in end-stage renal disease.


Asunto(s)
Anticoagulantes/efectos adversos , Mama/irrigación sanguínea , Enfermedad Arterial Periférica/inducido químicamente , Calcificación Vascular/inducido químicamente , Warfarina/efectos adversos , Anciano , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Fallo Renal Crónico/complicaciones , Mamografía , Enfermedad Arterial Periférica/diagnóstico por imagen , Medición de Riesgo , Factores de Riesgo , Calcificación Vascular/diagnóstico por imagen
19.
Cardiovasc Drugs Ther ; 35(5): 1045-1056, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33411112

RESUMEN

Ivabradine is a unique agent that is distinct from beta-blockers and calcium channel blockers as it reduces heart rate without affecting myocardial contractility or vascular tone. Ivabradine is a use-dependent inhibitor targeting the sinoatrial node. It is approved for use in the United States as an adjunct therapy for heart rate reduction in patients with heart failure with reduced ejection fraction. In this scenario, ivabradine has demonstrated improved clinical outcomes due to reduction in heart failure readmissions. However, there has been conflicting evidence from prospective studies and randomized controlled trials for its use in stable ischemic heart disease regarding efficacy in symptom reduction and mortality benefit. Ivabradine may also play a role in the treatment of patients with inappropriate sinus tachycardia, who often cannot tolerate beta-blockers and/or calcium channel blockers. In this review, we highlight the evidence for the nuances of using ivabradine in heart failure, stable ischemic heart disease, and inappropriate sinus tachycardia to raise awareness for its vital role in the treatment of select populations.


Asunto(s)
Fármacos Cardiovasculares/farmacología , Fármacos Cardiovasculares/uso terapéutico , Enfermedades Cardiovasculares/tratamiento farmacológico , Ivabradina/farmacología , Ivabradina/uso terapéutico , Fármacos Cardiovasculares/efectos adversos , Fármacos Cardiovasculares/farmacocinética , Humanos , Ivabradina/efectos adversos , Ivabradina/farmacocinética , Isquemia Miocárdica/tratamiento farmacológico , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Volumen Sistólico/efectos de los fármacos , Taquicardia Sinusal/tratamiento farmacológico
20.
Proc Natl Acad Sci U S A ; 115(48): 12188-12193, 2018 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-30429314

RESUMEN

Our understanding of the left-right (LR) asymmetry of embryonic development, in particular the contribution of intrinsic handedness of the cell or cell chirality, is limited due to the confounding systematic and environmental factors during morphogenesis and a ack of physiologically relevant in vitro 3D platforms. Here we report an efficient two-layered biomaterial platform for determining the chirality of individual cells, cell aggregates, and self-organized hollow epithelial spheroids. This bioengineered niche provides a uniform defined axis allowing for cells to rotate spontaneously with a directional bias toward either clockwise or counterclockwise directions. Mechanistic studies reveal an actin-dependent, cell-intrinsic property of 3D chirality that can be mediated by actin cross-linking via α-actinin-1. Our findings suggest that the gradient of extracellular matrix is an important biophysicochemical cue influencing cell polarity and chirality. Engineered biomaterial systems can serve as an effective platform for studying developmental asymmetry and screening for environmental factors causing birth defects.


Asunto(s)
Polaridad Celular , Células Epiteliales/citología , Animales , Técnicas de Cultivo de Célula , Perros , Células Epiteliales/química , Imagenología Tridimensional , Células de Riñón Canino Madin Darby , Modelos Biológicos , Rotación
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