RESUMO
In this research, the interactions of two azo dyes, Methyl Orange (MO) and Eriochrome Black T (EBT), with dissolved organic matter (DOM) in surface water were studied, emphasizing their removal using nano-filtration membranes (NF-270 and NF-90). High-Performance Size Exclusion Chromatography (HPSEC) findings indicated that the dyes' molecular weight in deionized (DI) water ranged from 500 to 15k Dalton (Da), adjusting peak intensities with Jingmi River (JM) water Beijing. Notably, when dyes were diluted in JM water, ultraviolet (UV533 & 466, and UV254), together with total organic carbon (TOC) parameters, revealed color removal rates of 99.49% (EBT), 94.2% (MO), 87.6% DOM removal, and 86% TOC removal for NF-90. The NF-90 membrane demonstrated a 75% flux decline for 50 mL permeate volume due to its finer pore structure and higher rejection effectiveness. In contrast, the NF-270 membrane showed a 60% decline in flux under the same conditions. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) analysis of dye-treated membranes in JM water revealed that the NF-270 showed a CC bond peak at 1660 cm-1 across various samples, while analyzing NF-90, the peaks at 1400 cm-1, 1040 cm-1, 750 cm-1, and 620 cm-1 disappeared for composite sample removal. The hydrophobicity of each membrane is measured by the contact angle (CA), which identified that initial CAs for NF-270 and NF-90 were 460 and 700, respectively, that were rapidly declined but stabilized after a few seconds of processing. Overall, this investigation shows that azo dyes interact with DOM in surface waters and enhance the removal efficiency of NF membranes.
Assuntos
Compostos Azo , Corantes , Filtração , Poluentes Químicos da Água , Purificação da Água , Compostos Azo/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Corantes/química , Purificação da Água/métodos , Filtração/métodos , Membranas Artificiais , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Inorganic coagulants such as poly aluminum ferric chloride (Al/Fe) are applied conventionally to sewage sludge dewatering and can be retained in the sludge cake, causing its conductivity to increase and generate secondary pollution. To reduce these disadvantages, there is a need to develop alternative, more sustainable chemicals as substitutes for conventional inorganic coagulants. In the present investigation, the application of a polymeric chitosan quaternary ammonium salt (CQAS) is explored as a complete, or partial, replacement for Al/Fe in the context of sludge dewatering processes. Laboratory experiments using digested sewage sludge showed that CQAS could effectively substitute for over 80 % of the Al/Fe inorganic coagulant in the sludge dewatering process. This substitution resulted in a reduction of sludge cake conductivity by more than 50 %. Simulation of sludge dewatering curves and imaging of the sludge surface indicated that the addition of CQAS led to an increase in nanosized pores, and a decrease in the specific resistance of the sludge filter cake as the dosage of Al/Fe decreased to around 30 %. The variations of fluorescence emission, quantum yield and carboxylic and amino groups, suggested that the chelating of Al/Fe decreased due to the bridging effects of CQAS. The CQAS had different flocculation bridging effects on various EPS fractions, which varied the amount of protein chelated with Al/Fe in each fraction. This study provides new information about the benefits of replacing conventional inorganic coagulants with natural organic polymers for sewage sludge dewatering, in terms of reduced sludge cake conductivity and greater dry solids content.
Assuntos
Quitosana , Compostos Férricos , Esgotos , Esgotos/química , Quitosana/química , Compostos Férricos/química , Compostos de Amônio Quaternário/química , Floculação , Cloretos/química , Eliminação de Resíduos Líquidos/métodos , Alumínio/químicaRESUMO
The presence of manganese(II) in drinking water sources poses a significant treatment difficulty for water utilities, thus necessitating the development of effective removal strategies. Treatment by Fe(VI), a combined oxidant and coagulant, has been identified as a potential green solution; however, its effectiveness is hampered by natural organic matter (NOM), and this underlying mechanism is not fully understood. Here, we investigated the inhibitory effect of three different types of NOM, representing terrestrial, aquatic, and microbial origins, on Mn(II) removal and floc growth during Fe(VI) coagulation. Results revealed that Fe(VI) coagulation effectively removes Mn(II), but NOM could inhibit its effectiveness by competing in oxidation reactions, forming NOM-Fe complexes, and altering floc aggregation. Humic acid was found to exhibit the strongest inhibition due to its unsaturated heterocyclic species that strongly bond to flocs and react with Fe(VI). For the first time, this study has presented a comprehensive elucidation of the atomic-level structure of Fe(VI) hydrolysis products by employing Extended X-ray Absorption Fine Structure Spectroscopy (EXAFS). Results demonstrated that NOM strengthened single-corner and double-corner coordination between FeO6 octahedrons that were consumed by Mn(II), resulting in an increased contribution of γ-FeOOH in the core-shell structure (γ-FeOOH shell and γ-F2O3 core), thereby inhibiting coagulation effects. Furthermore, NOM impeded the formation of stable manganite, resulting in more low-valence Mn(III) being incorporated in the form of an unstable intermediate. These findings provide a deeper understanding of the complex interplay between Fe coagulants, heavy metal pollution, and NOM in water treatment and offer insight into the limitations of Fe(VI) in practical applications.
Assuntos
Manganês , Purificação da Água , Oxirredução , Manganês/química , Purificação da Água/métodosRESUMO
Carlsberg subtilisin from Bacillus licheniformis PB1 was investigated as a potential feed supplement, through immobilizing on bentonite for improving the growth rate of broilers. Initially, the pre-optimized and partially-purified protease was extracted and characterized using SDS-PAGE with MW 27.0 KDa. The MALDI-TOF-MS/MS spectrum confirmed a tryptic peptide peak with m/z 1108.496 referring to the Carlsberg subtilisin as a protein-digesting enzyme with alkaline nature. The highest free enzyme activity (30 U/mg) was observed at 50°C, 1 M potassium phosphate, and pH 8.0. the enhanced stability was observed when the enzyme was adsorbed to an inert solid support with 86.39 ± 4.36% activity retention under 20 optimized conditions. Additionally, the dried immobilized enzyme exhibited only a 5% activity loss after two-week storage at room temperature. Structural modeling (Docking) revealed that hydrophobic interactions between bentonite and amino acids surrounding the catalytic triad keep the enzyme structure intact upon drying at RT. The prominent hygroscopic nature of bentonite facilitated protein structure retention upon drying. During a 46-days study, supplementation of boilers' feed with the subtilisin-bentonite complex promoted significant weight gain i.e. 15.03% in contrast to positive control (p = 0.001).
Assuntos
Aves Domésticas , Subtilisinas , Animais , Subtilisinas/metabolismo , Aves Domésticas/metabolismo , Galinhas/metabolismo , Bentonita , Espectrometria de Massas em Tandem , Subtilisina , Concentração de Íons de HidrogênioRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for about 672 million infections and 6.85 million deaths worldwide. Upon SARS-CoV-2 infection, Histone deacetylases (HDACs) hyperactivate the pro-inflammatory response resulting in stimulation of Acetyl-Coenzyme A and cholesterol for viral entry. HDAC3 inhibition results in the anti-inflammatory activity and reduction of pro-inflammatory cytokines that may restrict COVID-19 progression. Here, we have designed 44 conformational ensembles of previously known HD-TAC7 by enumerating torsions of dihedral angles tested for their binding preferences against HDAC3. Through scrutinizing their placements at active site and binding affinities, three hits were isolated. Cereblon (CRBN) is a well-known E3 ligase that facilitates Proteolysis Targeting Chimeras (PROTACs) targeting. Three entities, including HDAC3-binding moiety (4-acetamido-N-(2-amino-4 fluorophenyl) benzamide), a 6-carbon linker, and CRBN binding ligand (pomalidomide) were assembled to design 4 PROTACs followed by energy minimization and docking against HDAC3 and CRBN, respectively. Subsequent molecular dynamics (MD) and free energy analyses corroborated similar binding trends and favorable energy values. Among all cases, Met88, GLu106, Pro352, Trp380 and Trp388 residues of CRBN, and Pro23, Arg28, Lys194, Phe199, Leu266, Thr299 and Ile346 residues of HDAC3 were engaged in PROTAC binding. Thus, conformational dynamics of both HDAC3 and CRBN moieties are essential for the placement of PROTAC, resulting in target degradation. Overall, the proposed bifunctional small molecules may effectively target HDAC3, stimulating innate immune response to restrict COVID-19 hyperinflammation. This study supports the basis for designing new PROTACs by limiting the conformational search space that may prove more efficient for targeting the protein of interest.Communicated by Ramaswamy H. Sarma.
Assuntos
COVID-19 , Quimera de Direcionamento de Proteólise , Humanos , Proteólise , SARS-CoV-2/metabolismo , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Objective: To assess the perceptions of 2nd year medical students regarding certain approaches introduced in the course of Nutrition and Metabolism module. METHODS: The descriptive study was conducted at the Shifa College of Medicine, Islamabad, Pakistan, in December 2020, and comprised all 2nd year medical students who completed the Nutrition and Metabolism module in which new components had been added, including introduction to community nutrition, school visits, Islamic perspective of nutrition, journal club and e-posters. Data was collected using a questionnaire based on the modified Dundee Ready Education Environment Measure, and had 5 categories with a total of 25 questions that were scored on a 5-point Likert scale. Data was analysed using SPSS 22. RESULTS: Of the 100 students, 65(65%) were females and 35(35%) were males. The overall mean age was 20.5 ± 0.5 years. The total mean score was 74.68±2.53. Mean score for student's perception of learning was 38.17±0.17, student's perception of teachers 9.27±0.18, student's academic self-perceptions 12.1±0.11, student's perceptions of atmosphere 9.03±0.03 and student's social self-perceptions 6.11± 0.01. Conclusion: The perceptions medical students about innovations were positive, showing an encouraging attitude in terms of learning approach and outcome.
Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Estudos Transversais , Aprendizagem , Percepção Social , Inquéritos e QuestionáriosRESUMO
SHP-1 is a cytosolic tyrosine phosphatase that is primarily expressed in hematopoietic cells. It acts as a negative regulator of numerous signaling pathways and controls multiple cellular functions involved in cancer pathogenesis. This study describes the binding preferences of SHP-1 (pY536) to c-Srcopen (pY416) and c-Srcclose (pY527) through in silico approaches. Molecular dynamics simulation analysis revealed more conformational changes in c-Srcclose upon binding to SHP-1, as compared to its active/open conformation that is stabilized by the cooperative binding of the C-SH2 domain and C-terminal tail of SHP-1 to c-Src SH2 and KD. In contrast, c-Srcclose and SHP-1 interaction is mediated by PTP domain-specific WPD-loop (WPDXGXP) and Q-loop (QTXXQYXF) binding to c-Srcclose C-terminal tail residues. The dynamic correlation analysis demonstrated a positive correlation for SHP-1 PTP with KD, SH3, and the C-terminal tail of c-Srcclose. In the case of the c-Srcopen-SHP-1 complex, SH3 and SH2 domains of c-Srcopen were correlated to C-SH2 and the C-terminal tail of SHP-1. Our findings reveal that SHP1-dependent c-Src activation through dephosphorylation relies on the conformational shift in the inhibitory C-terminal tail that may ease the recruitment of the N-SH2 domain to phosphotyrosine residue, resulting in the relieving of the PTP domain. Collectively, this study delineates the intermolecular interaction paradigm and underlying conformational readjustments in SHP-1 due to binding with the c-Src active and inactive state. This study will largely help in devising novel therapeutic strategies for targeting cancer development.
Assuntos
Proteína Tirosina Quinase CSK , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Domínios de Homologia de src , Proteína Tirosina Quinase CSK/química , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 6/química , Proteínas Tirosina Fosfatases Contendo o Domínio SH2/química , NeoplasiasRESUMO
Cellular Src (c-Src) belongs to a non-receptor membrane-associated tyrosine kinase family that plays essential roles in cellular processes. Growing evidence suggests that R175L and W118A mutations in SH2/SH3 domains of c-Src functionally inactivate these domains leading to constitutive activation of kinase domain (KD). Here we modeled c-SrcR175L, c-SrcW118A and c-SrcW118A+R175L structures by inducing phosphorylation at Y416 or Y527, respectively to characterize the comparative dynamics in the active versus inactive states through molecular dynamics simulation assay. We observed more conformational readjustments in c-Srcopen than its close variants. In particular, C-terminal tail residues of c-SrcW118A-open and c-SrcW118A+R175L-open demonstrate significantly higher transitions. The cross-correlation analysis revealed an anticorrelation behavior in the motion of KD with respect to SH2, SH3 and the linker region of SrcW118A+R175L-open, while in c-SrcWT-open, SH2 and SH3 domains were anticorrelated, while KD and C-terminal tail motions were correlated. Due to these conformational differences, c-Src open forms exhibited lower interaction between pY527 and SH2 domain. Through detailed structural analysis, we observed a uniform myristate binding cavity in c-SrcWT-open, while the myristoyl pockets of mutant forms were deformed. We propose that constitutive activation of mutant Src forms may presumably be achieved by the prolonged membrane binding due to unusual conformations of C-terminal and myristoyl switch residues that may result in a higher dephosphorylation rate at pY527 in the myristoylated c-Src. Thus, our study establishes novel clues to decipher the constitutive activation status of c-Src in response to known mutations that may help in devising novel therapeutic strategies for cancer metastasis treatment.Communicated by Ramaswamy H. Sarma.
Assuntos
Proteínas Proto-Oncogênicas pp60(c-src) , Quinases da Família src , Quinases da Família src/genética , Quinases da Família src/química , Quinases da Família src/metabolismo , Fosforilação , Proteína Tirosina Quinase CSK/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/química , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Mutação , Domínios de Homologia de src/genéticaRESUMO
BACKGROUND: Mercury compounds are the world's third most hazardous substance. Mercury (II) chloride, also known as mercuric chloride (HgCl2), has been shown to have neurotoxic properties in a variety of forms. In numerous investigations, oxidative stress has been established as a key contributor to HgCl2-induced neurotoxicity. Carveol has been researched as an antioxidant and Nrf2-activator in several studies. This study was conducted to investigate if the carveol could protect mice against HgCl2-induced neuronal damage. METHODS: Mice were exposed to a dose of 0.4 mg/kg of HgCl2 and 20 mg/kg of carveol for 21 days. Animals were then subjected to behavioral evaluation through various methods such as open field test (OFT), elevated plus maze test (EPM), morris-water maze test (MWM), and Y-maze test. RESULTS: Results indicated hippocampal-related behavior anomalies which were improved significantly after carveol treatment. Oxidative stress was accompanied by excessive neuroinflammation, which was demonstrated by elevated levels of inflammatory markers such as TNF-α, p-NFkB, and COX-2, and were measured by Western blot, ELISA, and immunohistochemistry. These elevated levels of inflammatory markers were significantly mitigated upon treatment with carveol. To further investigate the participation of the JNK pathway, we used SP-600125 to inhibit JNK, which enhanced the neuroprotective effects of carveol. Moreover, molecular docking and modeling studies were used to validate these effects. CONCLUSION: Our findings indicate that carveol can inhibit the p-JNK pathway, thereby inhibiting HgCl2-induced apoptosis and downregulating the expression of inflammatory mediators.
Assuntos
Mercúrio , Fármacos Neuroprotetores , Síndromes Neurotóxicas , Animais , Antioxidantes/farmacologia , Encéfalo/metabolismo , Cloretos , Monoterpenos Cicloexânicos , Ciclo-Oxigenase 2/metabolismo , Substâncias Perigosas/farmacologia , Mediadores da Inflamação/metabolismo , Cloreto de Mercúrio/toxicidade , Camundongos , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Doenças Neuroinflamatórias , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/tratamento farmacológico , Estresse Oxidativo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Homologous to E6AP carboxyl-terminus (HECT)-type E3 ligase performs ubiquitin (Ub)-proteasomal protein degradation via forming a complex with E2â¼Ub. Enveloped viruses including SARS-CoV-2 escape from the infected cells by harnessing the E-class vacuolar protein-sorting (ESCRT) machinery and mimic the cellular system through PPAY motif-based linking to HECT Ub ligase activity. In the present study, we have characterized the binding pattern of E2UbcH5B to HECT domains of NEDD4L, WWP1, WWP2, HECW1, and HECW2 through in silico analysis to isolate the E2UbcH5B-specific peptide inhibitors that may target SARS-CoV-2 viral egression. Molecular dynamics analysis revealed more opening of E2UbcH5B-binding pocket upon binding to HECTNEDD4L, HECTWWP1, HECTWWP2, HECTHECW1, and HECTHECW2. We observed similar binding pattern for E2UbcH5B and mentioned HECT domains as previously reported for HECTNEDD4L where Trp762, Trp709, and Trp657 residues of HECTNEDD4L, HECTWWP1, and HECTWWP2 are involved in making contacts with Ser94 residue of E2UbcH5B. Similarly, corresponding to HECTNEDD4L Tyr756 residue, HECTWWP1, HECTWWP2, HECTHECW1, and HECTHECW2-specific Phe703, Phe651, Phe1387, and Phe1353 residues execute interaction with E2UbcH5B. Our analysis suggests that corresponding to Cys942 of HECTNEDD4L, Cys890, Cys838, Cys1574, and Cys1540 residues of HECTWWP1, HECTWWP2, HECTHECW1, and HECTHECW2, respectively are involved in E2-to-E3 Ub transfer. Furthermore, MM-PBSA free energy calculations revealed favorable energy values for E2UbcH5B-HECT complexes along with the individual residue contributions. Subsequently, two E2UbcH5B-derived peptides (His55-Phe69 and Asn81-Ala96) were tested for their binding abilities against HECT domains of NEDD4L, WWP1, WWP2, HECW1, and HECW2. Their binding was validated through substitution of Phe62, Pro65, Ile84, and Cys85 residues into Ala, which revealed an impaired binding, suggesting that the proposed peptide ligands may selectively target E2-HECT binding and Ub-transfer. Collectively, we propose that peptide-driven blocking of E2-to-HECT Ub loading may limit SARS-CoV-2 egression and spread in the host cells.
Assuntos
COVID-19 , Ubiquitina , Sítios de Ligação , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Humanos , Ligantes , Proteínas do Tecido Nervoso , Peptídeos/metabolismo , Ligação Proteica , SARS-CoV-2 , Ubiquitina/química , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/químicaRESUMO
Peroxisome proliferator-activated receptor-gamma (PPARγ) has been shown to have therapeutic promise in the treatment of ischemic stroke and is supported by several studies. To identify possible PPARγ activators, the current study used an in silico technique in conjunction with molecular simulations and in vivo validation. FDA-approved drugs were evaluated using molecular docking to determine their affinity for PPARγ. The findings of molecular simulations support the repurposing of rabeprazole and ethambutol for the treatment of ischemic stroke. Adult Sprague Dawley rats were subjected to transient middle cerebral artery occlusion (t-MCAO). Five groups were made as a sham-operated, t-MCAO group, rabeprazole +t-MCAO, ethambutol +t-MCAO, and pioglitazone +t-MCAO. The neuroprotective effects of these drugs were evaluated using the neurological deficit score and the infarct area. The inflammatory mediators and signaling transduction proteins were quantified using Western blotting, ELISA, and immunohistochemistry. The repurposed drugs mitigated cerebral ischemic injury by PPARγ mediated downregulation of nods like receptor protein 3 inflammasomes (NLRP3), tumor necrosis factor-alpha (TNF-α), cyclooxygenase 2 (COX-2), nuclear factor kappa-light-chain-enhancer of activated B cells (p-NF-kB), and c-Jun N-terminal kinase (p-JNK). Our data demonstrated that rabeprazole and ethambutol have neuroprotective potential via modulating the cytoprotective stress response, increasing cellular survival, and balancing homeostatic processes, and so may be suitable for future research in stroke therapy.
Assuntos
Isquemia Encefálica , AVC Isquêmico , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Animais , Encéfalo , Isquemia Encefálica/metabolismo , Etambutol/farmacologia , Etambutol/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Simulação de Acoplamento Molecular , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , PPAR gama/metabolismo , Rabeprazol/farmacologia , Rabeprazol/uso terapêutico , Ratos , Ratos Sprague-DawleyRESUMO
The excessive use of pesticides is posing major threats to humans and the environment. However, the environmental exposure and impact of pesticides in Pakistan have yet been systematically reviewed, despite the country's leading role in pesticide use. Therefore, this study identified and then reviewed 85 peer-reviewed scientific publications on the topic. It was found that, compared to the worldwide average, Pakistan had high consumptions of pesticides, with an alarming increase of 1169% in the last two decades. The quantities of pesticides used followed an order of pyrethroids > organophosphates > organochlorines > carbamates, but organochlorines were the most problematic due to their environmental occurrence, the ability to transport across the media, and identified human and ecological toxicities. Additionally, the misuse or overuse of pesticides by farmers is prevailing due to insufficient knowledge about the risks, which leads to high risks in occupational exposure. These issues are further aggravated by the illegal use or continuous impacts of banned organochlorine pesticides. For the future, we suggested the establishment of organized monitoring, assessment, and reporting program based on environmental laws to minimize contamination and exposure to pesticides in Pakistan. Remediation of the contaminated areas to mitigate the adverse environmental-cum-health impacts are recommended in the most affected regions.
Assuntos
Hidrocarbonetos Clorados , Praguicidas , Meio Ambiente , Exposição Ambiental/análise , Fazendeiros , Humanos , Paquistão , Praguicidas/análiseRESUMO
Cardiac hypertrophy results in the higher rate of heart failures among aged groups. Klotho is an anti-aging protein that is involved in the regulation of VEGF-mediated Ca2+ entry by direct interaction with Vascular endothelial growth factor receptor 2 (VEGFR2) and transient receptor potential canonical Ca2+ channel 1 (TRPC1). Here, in this study, through in silico analysis, we modeled TRPC1 3-dimensional structure and followed by its optimization, characterized the interaction pattern of TRPC1, Klotho and VEGFR2. Subsequent molecular dynamics (MD) simulation analysis revealed that Klotho-specific (P520-N630) region exhibited interaction with VEGFR2, while its C-terminal region (I822-A931) demonstrated binding to the 3rd extracellular loop of TRPC1 that is adjacent to pore region. Through TRPC1 homotetramer formation, the residues in the periphery of pore region were carefully evaluated. In order to scrutinize known Ca2+ channel blockers for their ability to bind at the pore region of TRPC1, 31 known compounds were tested through docking runs and three hits, named as diltiazem impurity B (b3), diltiazem (b5) and felodipine (b6) were selected for detailed binding analysis through MD runs. Evidently, inhibitor-bound TRPC1 pore area was more constricted (8.6 Å2, 25.1 Å2 and 18.8 Å2, respectively) than apo-TRPC1 (60 Å2). These findings suggest that Ca+2 channel blockers may serve as promising agents to impair the TRPC1 functional store-operated calcium channel (SOCC) activity in the old patients lacking Klotho expression. Thus, pore region of homotetrameric TRPC1 may be blocked via repurposing of known Ca+2 blockers to antagonize TRPC signaling for the treatment of cardiac hypertrophy.
Assuntos
Bloqueadores dos Canais de Cálcio , Canais de Cátion TRPC , Idoso , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Sinalização do Cálcio , Cardiomegalia/tratamento farmacológico , Diltiazem , Humanos , Canais de Cátion TRPC/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
Mercury is a highly toxic and highly mobile heavy metal. It has been regarded as more toxic than other nonessential and toxic nonradioactive heavy metals. Moreover, it has a high tendency of bioaccumulation and biomagnification in the ecosystem. This study aimed to assess the environmental and health risks related to Hg. Seventy studies related to Hg in environmental media, aquatic biota, and food stuffs across Pakistan were reviewed, and their concentrations were used for ecological and human health risk assessments. High concentrations of Hg were reported in the environment, with maximum concentrations of 72 mg L-1, 144 mg kg-1, 887 mg kg-1, and 49,807 ng m-3 in surface water, surface soil, surface sediments, and urban atmosphere, respectively. The possible non-carcinogenic health risk (hazard quotient) of Hg was assessed in soil, water, and fish. High risks were calculated for seafood and vegetable consumption, while low risks were estimated for soils and groundwater ingestion and exposure. Overall, children showed higher risks than adults. Last, the risk quotient analysis (RQ) revealed significant risks for aquatic species. RQs showed that multiple species, especially those with smaller resilience, could face long-term detrimental impacts. High, medium, and low risks were calculated from 66.66, 16.17, and 16.17% of the reported Hg concentrations.
Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Animais , Ecossistema , Monitoramento Ambiental , Contaminação de Alimentos/análise , Mercúrio/análise , Metais Pesados/análise , Paquistão , Medição de Risco , Poluentes do Solo/análiseRESUMO
Tribbles pseudokinases, Tribbles homolog 1 (TRIB1), Tribbles homolog 2 (TRIB2), and Tribbles homolog 3 (TRIB3), bind to constitutive photomorphogenesis protein 1 (COP1) E3 ligase to mediate the regulation of ß-catenin expression. The interaction mechanism between COP1 E3 ligase and ß-catenin has not been addressed to date. Based on the functional presence of TRIBs in wingless-related integration site (WNT) signaling, we analyzed their interaction patterns with ß-catenin and COP1. Here, through in silico approaches, we ascribe the COP1 binding pattern against TRIBs and ß-catenin. TRIB1 (355-DQIVPEY-361), TRIB2 (326-DQLVPDV-332), and TRIB3 (333-AQVVPDG-339) peptides revealed a shallow binding pocket at the COP1 interface to accommodate the V-P sequence motif. Reinvigoration of the comparative binding pattern and subtle structural analysis via docking, molecular dynamics simulations, molecular mechanics Poisson-Boltzmann surface area, topological, and tunnel analysis revealed that both ß-catenin phosphodegron (DSGXXS) and TRIB (D/E/AQXVPD/E) motifs occupied a common COP1 binding site. Current study suggests a structural paradigm of TRIB homologs bearing a conserved motif that may compete with ß-catenin phosphodegron signature for binding to WD40 domain of COP1. Thorough understanding of the structural basis for TRIB-mediated regulation of WNT/ß-catenin signaling may help in devising more promising therapeutic strategy for liver and colorectal cancers.
Assuntos
Ubiquitina-Proteína Ligases , beta Catenina , Sítios de Ligação , Simulação de Dinâmica Molecular , Transdução de Sinais , Ubiquitina-Proteína Ligases/química , beta Catenina/genética , beta Catenina/metabolismoRESUMO
OBJECTIVES: To determine the effectiveness of mechanical traction in supine versus prone lying position for lumbosacral radiculopathy. METHODS: A quasi experimental trial was conducted from April to September 2020 among sixty patients of chronic lumbosacral radiculopathy at Ibn e Siena Hospital, Multan. Participants were divided into two groups. Group-A (Supine) participants received lumbar traction in supine lying along with conventional treatment. Group-B (Prone) underwent the same treatment except the lumbar traction being applied in prone lying position. Participants were evaluated twice: at pre- treatment (week 0) and at the post treatment (week 2). Oswestry Disability Index and Numeric Pain Rating Scale were used as outcome measure. Data was analyzed on SPSS 23. RESULTS: The mean (±S.D) age of the patients was 39±5.7 vs. 40±5.3 years in supine vs. prone group respectively. Mean ODI score was 25.2±6.13 vs. 26.0±6.26 at the start of treatment in supine vs. prone position respectively while it was 19.45±7.12 vs. 11.05±4.40 at end of treatment in supine vs. prone position respectively. Mean NPRS score was 7.73±1.23 vs. 7.67±0.96 at start of treatment in supine vs. prone position respectively while it was 4.63±0.89 vs. 3.13±0.90 at the end of treatment in supine vs. prone position respectively. CONCLUSION: Lumbar traction in prone lying position is more effective than lumbar traction in supine lying position for the treatment of chronic lumbosacral radiculopathy.
RESUMO
Transcriptional coactivator myocyte enhancer factor 2B (MEF2B) mutations are the most common cause of germinal center-derived B-cell non-Hodgkin lymphoma. Despite well-established contributions in lymphomagenesis, the structure-function paradigms of these mutations are largely unknown. Here through in silico approaches, we present structural evaluation of two reported missense variants (K4E and Y69H) in MEF2B to investigate their impact on DNA-binding through molecular dynamics simulation assays. Notably, MEF2B-specific MADs box domain (Lys23, Arg24 and Lys31) and N-terminal loop residues (Gly2, Arg3, Lys4, Lys5, Ile6 and Asn13) contribute in DNA binding, while in MEF2BK4E, DNA binding is facilitated by Gly2, Arg3 and Arg91 (α3) residues. Conversely, in MEF2BY69H, Arg3, Lys5, Ser78, Arg79 and Asn81 residues mediate DNA binding. DNA binding induces pronounced conformational readjustments in MEF2BWT-specific α1-N-terminal loop region, while MEF2BY69H and MEF2BK4E exhibit fluctuations in both α1 and α3. Hydrogen (H)-bond occupancy analysis reveals a similar DNA binding behavior for MEF2WT and MEF2BY69H, compared to MEF2BK4E structure. The Anisotropic Network Model analysis depicts α1 and α3 as more fluctuant regions in MEF2BK4E as compared to other systems. MEF2BWT and MEF2BK4E, Tyr69 residue is involved in p300 binding thus possible influence of Y69H variation in the functions other than DNA binding, such as p300 co-activator recruitment may explain the reduced transcriptional activation of MEF2BY69H. Thus, present study may provide a structural basis of DNA recognition by pinpointing the underlying conformational changes in the dynamics of MEF2BK4E, MEF2BY69H, and MEF2BWT structures that may contribute in the identification of novel therapeutic strategies for lymphomagenesis.
Assuntos
DNA , Centro Germinativo , Fatores de Transcrição MEF2/química , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , MutaçãoRESUMO
OBJECTIVES: To determine the Prevalence and associated risk factors among patients with overactive bladder syndrome in Pakistan. METHODS: This was a community-based, face to face, cross sectional survey to calculate the prevalence and its associated risk factors. A sample of 1058 patients, women and men aged between 35 to 60 years having symptoms of overactive bladder was selected through convenience sampling from different cities of Pakistan during September to December 2020. Data was collected by using an Overactive Bladder Scoring System (OABSS) tool for prevalence and a developed questionnaire to rule out the risk factors. RESULTS: The prevalence was 27.4% (n=289) and it increased with age. The average ages for women and men were 44.60±7.88 and 46.14±7.69 years respectively. The OAB prevalence was the lowest among the participants aged 35-43 years 15.2% (n=55) while it was highest among those who were aged 53-60 years 49.6%, (n=127). The age, body mass index, diabetes mellitus, income, family history, parity and urinary tract infection were found to be significant associated risk factors for overactive bladder with p value <0.05. CONCLUSION: The overall prevalence of overactive bladder was 27.4% and it does not differ by gender, hypertension, pelvic surgery, smoking, constipation and sleep while it has significant association with age, body mass index, diabetes mellitus, income, parity and urinary tract infections.