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1.
Indian J Ophthalmol ; 72(6): 902-911, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38317323

RESUMEN

PURPOSE: Retinoschisis is a distinctive condition characterized by intraretinal layer clefts, primarily associated with X-linked recessive inheritance due to RS1 gene mutations. This study aims to uncover the RS1 mutation spectrum in a cohort of 22 X-linked retinoschisis cases from South India and emphasizes the genotypic and phenotypic associations within patients harboring only RS1 mutations. METHODS: A total of 22 probands were suspected of having X-linked retinoschisis. All study subjects underwent ophthalmic investigations, including assessments of visual acuity, fundus examination, optical coherence tomography (OCT), and electroretinogram (ERG). RS1 gene screening was conducted using Sanger sequencing, and the pathogenicity of the variants was assessed through Sorting Intolerant from Tolerant (SIFT) and PolyPhen-2 in silico tools. RESULTS: The study found that the probands had an average visual acuity of 0.79 ± 0.39 log of minimum angle of resolution (logMAR), ranging from 0.17 to 1.77. During fundus examination, the probands exhibited a characteristic spoke wheel-like pattern in the macular region. Furthermore, OCT analysis revealed distinct alterations in the inner retinal microstructure, and ERG results consistently showed a reduction in b-wave amplitude. Eventually, Sanger sequencing results showed hemizygous mutations in the RS1 gene in only 12 probands, including a novel missense mutation in the RS1 gene's signal sequence. CONCLUSION: This study provides valuable insights into the spectrum of RS1 mutations in X-linked retinoschisis probands from South India. It reveals distinct genotypic-phenotypic associations and highlights the clinical manifestations associated with the disease pathogenesis.


Asunto(s)
Electrorretinografía , Proteínas del Ojo , Genotipo , Mutación , Fenotipo , Retinosquisis , Tomografía de Coherencia Óptica , Agudeza Visual , Humanos , Retinosquisis/genética , Retinosquisis/diagnóstico , Retinosquisis/fisiopatología , Masculino , India/epidemiología , Tomografía de Coherencia Óptica/métodos , Proteínas del Ojo/genética , Adulto , Agudeza Visual/fisiología , Adolescente , Análisis Mutacional de ADN , Niño , Adulto Joven , Linaje , Femenino , Persona de Mediana Edad , ADN/genética , Retina/patología , Retina/diagnóstico por imagen , Retina/fisiopatología
2.
Int J Biol Macromol ; 251: 126189, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37586624

RESUMEN

Self-structure induction in a single stranded polyriboadenylic acid [poly (rA)] is an auspicious physiological phenomenon which switches off protein production in tumor cells. In the present study, the self-structure induction process in poly (rA) moiety was thoroughly investigated using various steady state and time resolved techniques. Optical melting pattern directly evidenced the formation of self-structured assembly in single stranded poly (rA) upon complexation with quinacrine. Further, UV-absorption spectroscopic studies revealed that quinacrine binds to poly (rA) in co-operative fashion and the indication of intercalative mode of binding first came out with the involvement of around two base pairs of poly (rA) in the complexation. Experimental observations established the unconventional or non-classical intercalation of quinacrine molecule inside self-structured duplex poly (rA) moiety. This complexation was accompanied with negative enthalpy change and positive entropy change; suggesting strong van der Waals and the H-bonding interactions as the major governing forces in the complexation. Moreover, ionic strength dependent binding study established that the non-polyelectrolytic forces were the dominating forces. Further, the photo physical behavior of QN was authenticated using time dependent density functional theory (TDDFT) where both the ground and excited states were exploited.

3.
Health Sci Rep ; 6(4): e1209, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37077184

RESUMEN

Background and Aims: Since the beginning of the SARS-CoV-2 pandemic, multiple new variants have emerged posing an increased risk to global public health. This study aimed to investigate SARS-CoV-2 variants, their temporal dynamics, infection rate (IFR) and case fatality rate (CFR) in Bangladesh by analyzing the published genomes. Methods: We retrieved 6610 complete whole genome sequences of the SARS-CoV-2 from the GISAID (Global Initiative on Sharing all Influenza Data) platform from March 2020 to October 2022, and performed different in-silico bioinformatics analyses. The clade and Pango lineages were assigned by using Nextclade v2.8.1. SARS-CoV-2 infections and fatality data were collected from the Institute of Epidemiology Disease Control and Research (IEDCR), Bangladesh. The average IFR was calculated from the monthly COVID-19 cases and population size while average CFR was calculated from the number of monthly deaths and number of confirmed COVID-19 cases. Results: SARS-CoV-2 first emerged in Bangladesh on March 3, 2020 and created three pandemic waves so far. The phylogenetic analysis revealed multiple introductions of SARS-CoV-2 variant(s) into Bangladesh with at least 22 Nextstrain clades and 107 Pangolin lineages with respect to the SARS-CoV-2 reference genome of Wuhan/Hu-1/2019. The Delta variant was detected as the most predominant (48.06%) variant followed by Omicron (27.88%), Beta (7.65%), Alpha (1.56%), Eta (0.33%) and Gamma (0.03%) variant. The overall IFR and CFR from circulating variants were 13.59% and 1.45%, respectively. A time-dependent monthly analysis showed significant variations in the IFR (p = 0.012, Kruskal-Wallis test) and CFR (p = 0.032, Kruskal-Wallis test) throughout the study period. We found the highest IFR (14.35%) in 2020 while Delta (20A) and Beta (20H) variants were circulating in Bangladesh. Remarkably, the highest CFR (1.91%) from SARS-CoV-2 variants was recorded in 2021. Conclusion: Our findings highlight the importance of genomic surveillance for careful monitoring of variants of concern emergence to interpret correctly their relative IFR and CFR, and thus, for implementation of strengthened public health and social measures to control the spread of the virus. Furthermore, the results of the present study may provide important context for sequence-based inference in SARS-CoV-2 variant(s) evolution and clinical epidemiology beyond Bangladesh.

4.
Ophthalmic Genet ; 43(2): 191-200, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34751623

RESUMEN

BACKGROUND: The diagnosis of retinal dystrophies can be challenging due to the spectrum of protean phenotypic manifestations. This study employed trio-whole-exome sequencing (trio-WES) to unveil the genetic cause of an inherited retinal disorder in a south Indian family. MATERIALS AND METHODS: Proband's initial ophthalmic examinations was performed in the year 2016. WES was performed on a proband-parent trio to identify causative mutation followed by Sanger validation, segregation analysis, sequence and structure-based computational analysis to assess its pathogenicity. Based on the genetic findings, detailed clinical reassessments were performed in year 2020 for the proband and available family members. RESULTS: WES revealed a novel homozygous BEST1 mutation c.G310A (p.D104N) in the proband and heterozygous for the parents, indicating autosomal recessive inheritance. Segregation analysis showed heterozygous mutation in maternal grandfather and normal genotype for younger brother and maternal grandmother. Moreover, the structure-based analysis revealed the mutation p.D104N in the cytoplasmic domain, causing structural hindrance by altering hydrogen bonds and destabilizing the BEST1 protein structure. Proband's clinical assessments were consistent with autosomal recessive bestrophinopathy (ARB) phenotype. Additionally, characteristic absent light rise and decreased light peak-to-dark trough ratio (LP:DT) was observed bilaterally in EOG. CONCLUSIONS: Our study demonstrates the utility of WES and clinical re-evaluations in establishing the precise diagnosis of autosomal recessive bestrophinopathy associated with a novel mutation, thus expanding the BEST1-related mutation spectrum.


Asunto(s)
Anomalías del Ojo , Distrofias Retinianas , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Bestrofinas/genética , Canales de Cloruro/genética , Electrorretinografía , Enfermedades Hereditarias del Ojo , Proteínas del Ojo/genética , Humanos , Masculino , Mutación , Linaje , Fenotipo , Enfermedades de la Retina , Secuenciación del Exoma
5.
Arch Biochem Biophys ; 712: 109042, 2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-34562470

RESUMEN

RNAs have become a well-known target for chemotherapeutic agents in the recent years. The tails of most eukaryotic m-RNA are characterized by the presence of a long polyadenylate sequence which plays an important role in its growth and maturation. This lays emphasis on development of molecular probes that target the polyadenylate sequence. Cryptolepine (hereafter, CRP) is an indoloquinoline alkaloid well known for its anti-malarial activities. A series of spectroscopic experiments namely absorption studies, fluorimetric studies and circular dichroism studies show that cryptolepine binds with single-stranded polyriboadenylic acid (hereafter, ss-poly (rA)) with a binding constant of ∼5 × 103 M-1 at 25 °C. Moreover thermal denaturation experiments show that the bound form of polyriboadenylic acid shows a characteristic transition profile. Such a profile is indicative of the ability of cryptolepine to induce self-assembly in the polyriboadenylic acid sequence on binding to it. Such ability of CRP to modulate the structural conformation of poly (rA), which in turn may cause functional aspects of the RNA to change, may give us a chance to develop effective alkaloid based chemotherapeutic agents.


Asunto(s)
Alcaloides Indólicos/metabolismo , Poli A/metabolismo , Quinolinas/metabolismo , Polarización de Fluorescencia , Alcaloides Indólicos/química , Conformación de Ácido Nucleico/efectos de los fármacos , Transición de Fase , Poli A/química , Quinolinas/química , Espectrometría de Fluorescencia , Termodinámica , Temperatura de Transición
6.
Int J Emerg Med ; 14(1): 54, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34525945

RESUMEN

BACKGROUND: Bystander cardiopulmonary resuscitation (CPR) rates remain fairly low through most communities despite multiple interventions through the years. Understanding the attitudes and fears behind CPR training and performance would help target education and training to raise the rates of bystander CPR and consequently survival rates of victims. 7909 participants at a single-day mass CPR training session in Singapore were given survey questionnaires to fill out. 6473 people submitted completed forms upon the conclusion of the training session. Some issues looked at were the overall level of difficulty of CPR, difficulty levels of specific skills, attitudes towards refresher training, attitudes towards performing CPR, and fears when doing so. RESULTS: The mean level of difficulty of CPR was rated 3.98 (scale of 1-10), with those with previous CPR training rating it easier. The skills rated most difficult were performing mouth-to-mouth breathing and chest compressions, while the easiest rated was recognizing non-responsiveness. A majority (69.7%) would agree to go for refresher training every 2 years and 88.7% felt everyone should be trained in CPR. 71.6% would perform full CPR for a member of the public in cardiac arrest and only 20.7% would prefer to only do chest compressions. The most cited fear was a low level of confidence, and fears of acquiring infections or aversion to mouth-to-mouth breathing were low. CONCLUSIONS: The survey results show that most participants in Singapore are keen to perform conventional CPR for a member of the public and can help to target future CPR training accordingly.

7.
Biochim Biophys Acta Gen Subj ; 1865(11): 129993, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34453987

RESUMEN

BACKGROUND: Low pH induced nucleic acid polymorphism and the interaction of naturally occurring small molecules with different polymorphic forms of DNA have been the focus in developing new drugs. Recent studies have revealed that low pH plays an active role in growth and development of cancer cells. Our target is to find whether and how the indoloquinoline alkaloid cryptolepine (CRP) interact with different polymorphic forms of natural DNA, in hope to explore this group of alkaloids as new therapeutics. METHODS: Multiple spectroscopic techniques that include UV-visible absorption spectrophotometry, fluorimetry, CD spectroscopy along with thermal melting studies were employed to characterize the interaction between the alkaloid cryptolepine with the B and protonated forms of DNA. RESULTS & CONCLUSIONS: Cryptolepine has been found to interact with either forms of DNA. The nature of binding is non-cooperative in both cases. Data show that the affinity of CRP to B form of DNA is relatively higher than that for the protonated form of DNA. Circular dichroic studies reveal that the alkaloid converts the left handed protonated DNA into bound right handed form. Fluorescence quenching experiments reveal that cryptolepine intercalates within the DNA base pairs. Thermal melting studies show that the alkaloid stabilises the DNA structures. GENERAL SIGNIFICANCE: Such non-B DNA structures are often present at the 'mutation hotspots' that are associated with genetic instability related diseases such as cancer. The ability of cryptolepine to interact to such non-B DNA structures makes it a useful substrate in the designing of potential chemotherapeutic agents.


Asunto(s)
ADN/química , Alcaloides Indólicos/química , Quinolinas/química , Sitios de Unión , Dicroismo Circular , Fluorometría , Estructura Molecular , Protones , Espectrofotometría Ultravioleta
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 246: 119008, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33038855

RESUMEN

Single stranded polyriboadenylic acid [poly (rA)] has been accepted widely as a suitable drug target owing to its vital role in the development of cancer since it controls gene expression during cell growth and differentiation. The biological properties of poly (rA) depend on its structural morphology. Pharmacologically active flavonoids can act as suitable binders to poly (rA) and significantly change its biophysical properties. Different factors favour flavonoid-poly (rA) binding. In our present work we have explored the role played by the position of hydroxyl groups in the flavonoids namely 3, 5, 6 and 7 hydroxyflavones in their course of interaction with poly (rA). A range of spectroscopic experiments reveal that 3HF binds best to poly (rA) among the four chosen flavonoids. This is probably due to the presence of a hydroxyl group in '3' position that enables it to exhibit ESIPT phenomenon which is missing for the other used flavonoids.


Asunto(s)
Flavonoides , Poli A , Fenómenos Biofísicos , Análisis Espectral
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 225: 117513, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31521000

RESUMEN

The use of bioactive flavonoids as drugs has long mesmerized the scientific world. Their small size and planar structure enables them to interact with limitless substrates especially biomolecules. Taxifolin is a flavonoid well known for its anti-oxidizing and metal chelating properties. Its interaction with a few biomolecules has been studied so far to exploit its pharmacological activities. Hemoglobin, an iron containing macromolecule acts as a major carrier protein and is also associated with the occurrence of many diseases. Our present study lays emphasis on the interaction of flavanonol taxifolin with bovine hemoglobin at physiological pH. This was achieved by monitoring the changes in the absorbance, fluorescence, anisotropic, lifetime and circular dichroic spectra. Benesi-Hildebrand plot determined a binding constant value of 20.0 × 103 M-1 at 25 °C. Stern-Volmer quenching studies reveal that the binding is associated with a static mode of quenching. The complexation is thermodynamically favored as indicated by the negative value of enthalpy and positive value of entropy changes seen from the van't Hoff plot. Theoretical DFT calculations were used to find out an optimized geometry and HOMO-LUMO energy gap for taxifolin. Molecular docking studies revealed the location of taxifolin inside the hemoglobin moiety.


Asunto(s)
Hemoglobinas/química , Hemoglobinas/metabolismo , Quercetina/análogos & derivados , Animales , Sitios de Unión , Bovinos , Dicroismo Circular , Polarización de Fluorescencia , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Simulación del Acoplamiento Molecular , Unión Proteica , Conformación Proteica , Quercetina/química , Quercetina/metabolismo , Espectrometría de Fluorescencia , Análisis Espectral/métodos , Termodinámica
11.
Int J Biol Macromol ; 138: 57-69, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31301395

RESUMEN

Chelerythrine (CHL) is a pharmacologically important molecule that appears in positively charged iminium and neutral alkanolamine form on varying the pH. Association of bovine hemoglobin (BHb) with iminium and alkanolamine forms of CHL is explored employing several spectroscopic and theoretical tools. Our results revealed that iminium form of CHL shows greater binding affinity than the neutral alkanolamine form, with nearly one binding site on the protein for both forms. Thermodynamic data showed that the iminium binding to BHb was characterized by negative enthalpy and positive entropy changes while the association of the alkanolamine CHL was accompanied with both positive enthalpy and entropy changes. Both forms of CHL have been found to quench the intrinsic fluorescence of BHb. From Förster's resonance energy transfer (FRET) studies, the binding distance between the energy acceptor (CHL) and donor (ß-Trp 37 of BHb) was found to be optimum for fluorescence quenching to occur. The conformational transformation of BHb induced by CHL complexation showed greater unfolding of the protein architecture for the iminium interaction from CD spectroscopy. Molecular docking study revealed that both iminium and alkanolamine form of CHL reside near ß-Trp 37 at the α1ß2 interface of BHb.


Asunto(s)
Benzofenantridinas/metabolismo , Hemoglobinas/metabolismo , Simulación del Acoplamiento Molecular , Animales , Bovinos , Transferencia de Energía , Hemoglobinas/química , Concentración de Iones de Hidrógeno , Unión Proteica , Conformación Proteica , Termodinámica
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 223: 117293, 2019 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-31260885

RESUMEN

The association of a putative bioactive alkaloid nitidine (NIT) with blood protein bovine hemoglobin (BHb) was investigated by employing various biophysical and molecular docking techniques. NIT binding to BHb was first characterized by hypochromic effect on the Soret band absorption of BHb from spectrophotometric studies. Spectrofluorimetric titration and unchanged fluorescence lifetime of BHb confirmed ground state complexation followed by the static nature of the emission quenching mechanism of the protein induced by NIT. Substantial conformational changes in the protein structure were established from circular dichroism study. Conformational perturbation results a lowering in the α-helical organization of the tetrameric protein structure. Thermodynamics of the binding suggest that the binding is exothermic with a favourable small positive entropy change and negative enthalpy change making a sense of electrostatic interaction as the major acting force. Experimentally calculated free energy change for the NIT-BHb interaction was found to be -7.50 kcal mol-1 which is in well agreement to the theoretical docking energy value of -6.36 kcal mol-1. AutoDock based molecular docking suggests the internal cavity of BHb as the preferred binding position of NIT. Overall this manuscript depicts consequences on the molecular interaction of NIT with BHb from structural and energetic standpoints providing a profound insight into protein-ligand association.


Asunto(s)
Alcaloides/química , Alcaloides/metabolismo , Benzofenantridinas/química , Benzofenantridinas/metabolismo , Hemoglobinas/metabolismo , Animales , Sitios de Unión , Bovinos , Dicroismo Circular , Cinética , Conformación Molecular , Simulación del Acoplamiento Molecular , Unión Proteica , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Termodinámica , Triptófano/química
13.
Polymers (Basel) ; 11(2)2019 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-30960181

RESUMEN

Recently, we have developed an eco-friendly method for the preparation of a renewable dicarboxylic acid 2,5-furandicarboxylic acid (FDCA) from biomass-based 5-hydroxymethylfrufural (HMF). In the present work, we optimized our reported method, which used phosphate buffer and Fe(OH)3 as the stabilizer to improve the stability of potassium ferrate, then got a purified FDCA (up to 99%) in high yield (91.7 wt %) under mild conditions (25 °C, 15 min, air atmosphere). Subsequently, the obtained FDCA, along with 1,6-hexanediol (HDO), which was also made from HMF, were used as monomers for the synthesis of poly(hexylene 2,5-furandicarboxylate) (PHF) via direct esterification, and triphenyl phosphite was used as the antioxidant to alleviate the discoloration problem during the esterification. The intrinsic viscosity, mechanical properties, molecular structure, thermal properties, and degradability of the PHFs were measured or characterized by Koehler viscometer, universal tensile tester, Nuclear Magnetic Resonance (NMR), Fourier-transform Infrared (FTIR), X-ray diffraction (XRD), Differential Scanning Calorimeter (DSC), Derivative Thermogravimetry (DTG), Scanning Electron Microscope (SEM), and weight loss method. The experimental evidence clearly showed that the furan-aromatic polyesters prepared from biomass-based HMF are viable alternatives to the petrochemical benzene-aromatic polyesters, they can serve as low-melting heat bondable fiber, high gas-barrier packaging material, as well as specialty material for engineering applications.

14.
Bioresour Technol ; 281: 440-448, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30876797

RESUMEN

Recently, the worldwide production of dissolving pulp has grown rapidly. Enzymatic technologies play an important role in producing high-quality dissolving pulp, due to their green, mild conditions, high specificity and efficiency. In this review, the relevant publications regarding enzyme applications for dissolving pulp are summarized. Cellulase and xylanase are two major enzymes used for this purpose. Cellulase can improve the quality of dissolving pulp, such as improving the reactivity/accessibility, controlling the intrinsic viscosity and adjusting the molecular weight. Xylanase is mainly used to increase the purity of the dissolving pulp and improve the pulp brightness. Furthermore, in order to increase the enzymatic treatment efficiency, the enzymatic technology can be combined with other techniques, including mechanical refining, fiber fractionations, alkali treatment and use of additives. The advantages, disadvantages and practical implications are analyzed. Also, the potential of other enzymes (such as laccase, mannanase) are discussed.


Asunto(s)
Celulosa/metabolismo , Madera/química , Celulasa/metabolismo , Endo-1,4-beta Xilanasas/metabolismo , Viscosidad
15.
Int J Biol Macromol ; 120(Pt A): 1156-1169, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30172817

RESUMEN

Fisetin (FTN) and its metal chelates are critically important since this bioflavonoid possesses wide range of pharmacological properties. Usually, metal binding property enhances the pharmaceutical activity of FTN. Thus in this report, we investigated the complexation of FTN with biologically essential metal ion Cu2+ and further examined the effect of such complexation on calf thymus DNA (CT DNA) binding in comparison with free FTN. We have characterized the complex formation of FTN with Cu2+ using UV-visible, fluorimetric and FTIR studies. Within our experimental concentration range we found that, FTN forms a 2:1 complex with Cu2+ in terms of FTN:Cu2+. Spectroscopic analysis revealed that both FTN and FTN2-Cu2+ complex bind with CT DNA and the binding constant is higher for free FTN. Perturbation of circular dichroism spectrum of CT DNA was observed in presence of free FTN due to structural alteration in DNA double helix. Viscometric, thermal melting and fluorescence quenching study confirm that FTN intercalates in between the base pairs of CT DNA while its Cu (II) complex acts as a groove binder. Molecular docking study further confirms that FTN intercalates into AT rich region of CT DNA while its Cu (II) complex binds at the minor groove.


Asunto(s)
Complejos de Coordinación/química , Cobre/química , ADN/química , Flavonoides/química , Animales , Bovinos , Quelantes/química , Quelantes/metabolismo , Dicroismo Circular , Complejos de Coordinación/metabolismo , Flavonoides/metabolismo , Flavonoles , Simulación del Acoplamiento Molecular , Conformación de Ácido Nucleico/efectos de los fármacos , Agua/química
16.
Int J Biol Macromol ; 119: 1106-1112, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30098360

RESUMEN

Polymorphism of DNA plays a very important part of research relating to the drug-DNA interactions. Here main focus of our investigation is to monitor the interaction of the benzophenanthridine plant alkaloid, nitidine (NIT) with two different forms of DNA i.e. B-DNA and protonated form of DNA maintaining proper temperatures and buffer conditions. Binding interaction of NIT was ascertained from the UV-Visible spectroscopic and spectrofluorimetric titration experiments. Binding constants of the interactions of NIT with different polymorphic forms were calculated from UV-absorption study. The binding constants were 3.8 × 105 M-1 and 1.3 × 105 M-1 for B-DNA and protonated DNA respectively. Red shift in the absorption maxima of NIT on binding with DNA, comparatively greater relative quenching of fluorescence intensity of free NIT than bound NIT, perturbation in the CD spectrum of DNA in presence of NIT confirmed the mode of binding as intercalation. Moreover, spectropolarimetric experiment confirms that left handed protonated form of DNA gets partially converted to the canonical B form of DNA while binds with NIT. Besides the CD experiment, thermal melting experiment also showed that on binding with NIT stabilization of protonated DNA was increased to an appreciable extent.


Asunto(s)
Emparejamiento Base/efectos de los fármacos , Benzofenantridinas/farmacología , ADN/química , Protones , Temperatura , Animales , Bovinos , Concentración de Iones de Hidrógeno , Desnaturalización de Ácido Nucleico , Análisis Espectral
17.
BMJ ; 362: k3310, 2018 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-30158148

RESUMEN

OBJECTIVE: To conduct a systematic review and meta-analysis of epidemiological studies investigating the association of arsenic, lead, cadmium, mercury, and copper with cardiovascular disease. DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed, Embase, and Web of Science searched up to December 2017. REVIEW METHODS: Studies reporting risk estimates for total cardiovascular disease, coronary heart disease, and stroke for levels of arsenic, lead, cadmium, mercury, or copper were included. Two investigators independently extracted information on study characteristics and outcomes in accordance with PRISMA and MOOSE guidelines. Relative risks were standardised to a common scale and pooled across studies for each marker using random effects meta-analyses. RESULTS: The review identified 37 unique studies comprising 348 259 non-overlapping participants, with 13 033 coronary heart disease, 4205 stroke, and 15 274 cardiovascular disease outcomes in aggregate. Comparing top versus bottom thirds of baseline levels, pooled relative risks for arsenic and lead were 1.30 (95% confidence interval 1.04 to 1.63) and 1.43 (1.16 to 1.76) for cardiovascular disease, 1.23 (1.04 to 1.45) and 1.85 (1.27 to 2.69) for coronary heart disease, and 1.15 (0.92 to 1.43) and 1.63 (1.14 to 2.34) for stroke. Relative risks for cadmium and copper were 1.33 (1.09 to 1.64) and 1.81 (1.05 to 3.11) for cardiovascular disease, 1.29 (0.98 to 1.71) and 2.22 (1.31 to 3.74) for coronary heart disease, and 1.72 (1.29 to 2.28) and 1.29 (0.77 to 2.17) for stroke. Mercury had no distinctive association with cardiovascular outcomes. There was a linear dose-response relation for arsenic, lead, and cadmium with cardiovascular disease outcomes. CONCLUSION: Exposure to arsenic, lead, cadmium, and copper is associated with an increased risk of cardiovascular disease and coronary heart disease. Mercury is not associated with cardiovascular risk. These findings reinforce the importance of environmental toxic metals in cardiovascular risk, beyond the roles of conventional behavioural risk factors.


Asunto(s)
Enfermedades Cardiovasculares/inducido químicamente , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente , Contaminantes Ambientales/toxicidad , Contaminación Ambiental/efectos adversos , Metales Pesados/toxicidad , Humanos , Medición de Riesgo , Factores de Riesgo
18.
J Community Genet ; 9(3): 195-199, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29470710

RESUMEN

Risk prediction models have a key role in stratified disease prevention, and the incorporation of genomic data into these models promises more effective personalisation. Although the clinical utility of incorporating genomic data into risk prediction tools is increasingly compelling, at least for some applications and disease types, the legal and regulatory implications have not been examined and have been overshadowed by discussions about clinical and scientific utility and feasibility. We held a workshop to explore relevant legal and regulatory perspectives from four EU Member States: France, Germany, the Netherlands and the UK. While we found no absolute prohibition on the use of such data in those tools, there are considerable challenges. Currently, these are modest and result from genomic data being classified as sensitive data under existing Data Protection regulation. However, these challenges will increase in the future following the implementation of EU Regulations on data protection which take effect in 2018, and reforms to the governance of the manufacture, development and use of in vitro diagnostic devices to be implemented in 2022. Collectively these will increase the regulatory burden placed on these products as risk stratification tools will be brought within the scope of these new Regulations. The failure to respond to the challenges posed by the use of genomic data in disease risk stratification tools could therefore prove costly to those developing and using such tools.

19.
PLoS One ; 11(6): e0157417, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27315068

RESUMEN

IMPORTANCE: Vasomotor symptoms (hot flushes and night sweats) and other symptoms, including depression, anxiety and panic attacks, are commonly experienced by menopausal women and have been associated with an unfavourable cardiovascular risk profile. OBJECTIVE: To investigate whether presence of menopausal symptoms is associated with the development of cardiovascular disease (CVD). METHODS: Five electronic databases (Medline, EMBASE and Web of Science) were search until February 17th, 2015 to identify relevant studies. Observational cohort studies or randomised intervention studies were eligible for inclusion if they followed participants prospectively (at least 1 year of follow-up), and reported relevant estimates on the association of any vasomotor symptoms, or other menopausal symptoms, with risk of CVD, coronary heart disease (CHD), or stroke in perimenopausal, menopausal, or postmenopausal women. Data were extracted by two independent reviewers using a pre-designed data collection form. Separate pooled relative risks (RRs) for age and non-established cardiovascular risk factors (e.g., education, ethnicity) adjusted data and for established cardiovascular risk factors and potential mediators-adjusted data (e.g., smoking, body mass index, and hypertension) were calculated. RESULTS: Out of 9,987 initially identified references, ten studies were selected, including 213,976 women with a total of 10,037 cardiovascular disease outcomes. The age and non-established cardiovascular risk factors adjusted RRs) [95% confidence intervals] for development of CHD, Stroke and CVD comparing women with and without any menopausal symptoms were 1.34 [1.13-1.58], 1.30 [0.99-1.70], 1.48 [1.21-1.80] respectively, and the corresponding RRs adjusted for cardiovascular risk factors and potential mediators were 1.18 [1.03-1.35], 1.08 [0.89-1.32], 1.29 [0.98-1.71]. However, these analyses were limited by potential unmeasured confounding and the small number of studies on this topic. CONCLUSION: Presence of vasomotor symptoms and other menopausal symptoms are generally associated with an increased risk of cardiovascular disease, which is mainly explained by cardiovascular risk factors.


Asunto(s)
Enfermedades Cardiovasculares/fisiopatología , Sofocos/fisiopatología , Menopausia/fisiología , Sistema Vasomotor/fisiopatología , Anciano , Enfermedades Cardiovasculares/epidemiología , Femenino , Sofocos/epidemiología , Humanos , Hipertensión/epidemiología , Hipertensión/fisiopatología , Persona de Mediana Edad , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/fisiopatología , Sudoración/fisiología
20.
J Pers Med ; 5(2): 191-212, 2015 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-26068647

RESUMEN

There is growing evidence that inclusion of genetic information about known common susceptibility variants may enable population risk-stratification and personalized prevention for common diseases including cancer. This would require the inclusion of genetic testing as an integral part of individual risk assessment of an asymptomatic individual. Front line health professionals would be expected to interact with and assist asymptomatic individuals through the risk stratification process. In that case, additional knowledge and skills may be needed. Current guidelines and frameworks for genetic competencies of non-specialist health professionals place an emphasis on rare inherited genetic diseases. For common diseases, health professionals do use risk assessment tools but such tools currently do not assess genetic susceptibility of individuals. In this article, we compare the skills and knowledge needed by non-genetic health professionals, if risk-stratified prevention is implemented, with existing competence recommendations from the UK, USA and Europe, in order to assess the gaps in current competences. We found that health professionals would benefit from understanding the contribution of common genetic variations in disease risk, the rationale for a risk-stratified prevention pathway, and the implications of using genomic information in risk-assessment and risk management of asymptomatic individuals for common disease prevention.

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