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1.
Nanoscale ; 16(15): 7612-7625, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38512302

RESUMO

On-surface synthesis often proceeds under kinetic control due to the irreversibility of key reaction steps, rendering kinetic studies pivotal. The accurate quantification of reaction rates also bears potential for unveiling reaction mechanisms. Temperature-Programmed X-ray Photoelectron Spectroscopy (TP-XPS) has emerged as an analytical tool for kinetic studies with splendid chemical and sufficient temporal resolution. Here, we demonstrate that the common linear temperature ramps lead to fitting ambiguities. Moreover, pinpointing the reaction order remains intricate, although this key parameter entails information on atomistic mechanisms. Yet, TP-XPS experiments with a stepped temperature profile comprised of isothermal segments facilitate the direct quantification of rate constants from fitting time courses. Thereby, rate constants are obtained for a series of temperatures, which allows independent extraction of both activation energies and pre-exponentials from Arrhenius plots. By using two analogous doubly versus triply brominated aromatic model compounds, we found that their debromination on Ag(111) is best modeled by second-order kinetics and thus proceeds via the involvement of a second, non-obvious reactant. Accordingly, we propose that debromination is activated by surface supplied Ag adatoms. This hypothesis is supported by Density Functional Theory (DFT) calculations. We foresee auspicious prospects for this TP-XPS variant for further exploring the kinetics and mechanisms of on-surface reactions.

2.
J Am Chem Soc ; 146(4): 2568-2573, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38230667

RESUMO

Chemical separations are expensive, consuming 10-15% of humanity's global energy budget. Many current separation methods employ thermal energy for distillation, often through the combustion of carbon-containing fuels, or extractions and crystallizations from organic solvents, which must then be discarded or redistilled, with a substantial energetic cost. The direct use of renewable energy sources, such as light, could enable the development of novel separations processes, as is required for the transition away from fossil fuel use. Metal-organic capsules, which can selectively bind molecules from mixtures, can provide the foundation for these novel separations processes. Here we report a tetrahedral metal-organic capsule bearing light-responsive diazo moieties around its metal-ion vertices. This capsule can be used to selectively separate progesterone from a mixture of steroids in a process driven by visible light energy. Our process combines biphasic extraction and selective binding of progesterone with the light-driven release of this molecule in purified form. Ultimately, our process might be adapted to the purifications of the many other fine chemical products that are bound selectively by capsules.

3.
Int J Biol Macromol ; 256(Pt 2): 128417, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38016612

RESUMO

Acetyl-CoA carboxylase (ACCase) is crucial for fatty acid biosynthesis and has potential applications in lipid accumulation and advanced biofuel production. Mutations like S659A and S1157A in Saccharomyces cerevisiae ACCase remove the Snf1-regulation sites, resulting in increased enzyme activity with positive effects on the fatty acid pathway. However, the molecular-level understanding of these mutations on ACCase activity remains unexplored. Here, molecular dynamics simulation was conducted to investigate the mutations-induced conformational changes in S. cerevisiae ACCase. The wild-type ACCase was observed to have significant deviation in structure compared to mutant. Additionally, fluctuation of residues associated with biotin binding and Snf1-recognition were reduced in mutant compared to wild-type. Furthermore, the wild-type demonstrated opening motions of the domains, whereas the mutant showed closing movement. The mutation-induced conformational changes were analysed using network parameters, i.e., cliques/communities. The mutant showed an increase in sizes of several communities in AC3-AC4-AC5 domains leading to rigidification. Also, a new community was added in AC1-BT in the mutant, which suggested a substantial shift in the protein conformation. Thus, this study provides a theoretical understanding of the increased activity of ACCase due to two mutations, which can pave the path for enzyme engineering towards improved fatty acid-based fuel and chemical production.


Assuntos
Acetil-CoA Carboxilase , Saccharomyces cerevisiae , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/química , Acetil-CoA Carboxilase/metabolismo , Mutação , Ácidos Graxos/metabolismo , Simulação de Dinâmica Molecular
4.
Curr Pediatr Rev ; 20(3): 365-369, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36809946

RESUMO

AIMS: The study aims to investigate the presence of TORCH infections in a child with bilateral cataracts and deafness and report the ToRCH-serology screening profile (Toxoplasma gondii (TOX), rubella (RV), cytomegalovirus (CMV), and herpes simplex virus (HSV-I/II)) in pediatric cataract and deafness. METHODS: Cases that had a clear clinical history of congenital cataracts and congenital deafness were included in the study. The study population consisted of 18 bilateral cataracts and 12 bilateral deafness child who was admitted to AIIMS Bhubaneswar for cataract surgery and cochlear implantation, respectively. Sera of all children were tested qualitatively and quantitatively for IgG/IgM-antibodies against ToRCH agents in a sequential manner. RESULTS: Anti-IgG antibodies against the torch panel were detected in all cataract and deafness patients. Anti-CMV IgG was detected in 17 of 18 bilateral cataract children and 11 of 12 bilateral deaf children. The rates of anti-CMV IgG antibody positivity were significantly higher. In the cataract group, 94.44% and in the deafness group, 91.66% of the patient was Anti-CMV IgG positive. Besides this, 77.7 % of the patient from the cataract group and 75% from the deafness group was anti- RV IgG antibody positive. In bilateral cataract patients, IgG-alone seropositive cases were mostly attributed to CMV (94.44%; 17/18), followed by RV (77.70%; 14/18), HSV-I (27.70%; 5/18), TOX (27.70%; 5/18), and HSV-II (16.60%; 3/18). In bilateral deafness patients, the spectrum of IgG alone seropositive cases was almost the same except for TOX (0/12). CONCLUSION: The current study recommends interpreting ToRCH-screening in pediatric cataracts and deafness with caution. Interpretation should include both serial qualitative and quantitative assays in tandem with clinical correlation to minimize diagnostic errors. The sero-clinical-positivity needs to be tested in older children who might pose a threat to the spread of infection.


Assuntos
Catarata , Infecções por Citomegalovirus , Surdez , Humanos , Criança , Estudos Soroepidemiológicos , Perda Auditiva Bilateral , Centros de Atenção Terciária , Citomegalovirus , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia , Simplexvirus , Imunoglobulina G , Anticorpos Antivirais , Catarata/epidemiologia
5.
Glycobiology ; 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039077

RESUMO

Phosphatidyl-myo-inositol mannosides (PIMs), Lipomannan (LM), and Lipoarabinomannan (LAM) are essential components of the cell envelopes of mycobacteria. At the beginning of the biosynthesis of these compounds, phosphatidylinositol (PI) is mannosylated and acylated by various enzymes to produce Ac 1/2PIM4, which is used to synthesize either Ac1/2PIM6 or LM/LAM. The protein PimE, a membrane-bound glycosyltransferase (GT-C), catalyzes the addition of a mannose group to Ac1PIM4 to produce Ac1PIM5, using polyprenolphosphate mannose (PPM) as the mannose donor. PimE-deleted Mycobacterium smegmatis (Msmeg) showed structural deformity and increased antibiotic and copper sensitivity. Despite knowing that the mutation D58A caused inactivity in Msmeg, how PimE catalyzes the transfer of mannose from PPM to Ac1/2PIM4 remains unknown. In this study, analyzing the AlphaFold structure of PimE revealed the presence of a tunnel through the D58 residue with two differently charged gates. Molecular docking suggested PPM binds to the hydrophobic tunnel gate, whereas Ac1PIM4 binds to the positively charged tunnel gate. Molecular dynamics (MD) simulations further demonstrated the critical roles of the residues N55, F87, L89, Y163, Q165, K197, L198, R251, F277, W324, H326, and I375 in binding PPM and Ac1PIM4. The mutation D58A caused a faster release of PPM from the catalytic tunnel, explaining the loss of PimE activity. Along with a hypothetical mechanism of mannose transfer by PimE, we also observe the presence of tunnels through a negatively charged aspartate or glutamate with two differently-charged gates among most GT-C enzymes. Common hydrophobic gates of GT-C enzymes probably harbour sugar donors, whereas, differently-charged tunnel gates accommodate various sugar-acceptors.

6.
Front Immunol ; 14: 1241755, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38146363

RESUMO

Background and aims: Alcoholic liver disease (ALD) is the leading cause of the liver cirrhosis related death worldwide. Excessive alcohol consumption resulting enhanced gut permeability which trigger sensitization of inflammatory cells to bacterial endotoxins and induces secretion of cytokines, chemokines leading to activation of stellate cells, neutrophil infiltration and hepatocyte injury followed by steatohepatitis, fibrosis and cirrhosis. But all chronic alcoholics are not susceptible to ALD. This study investigated the causes of differential immune responses among ALD patients and alcoholic controls (ALC) to identify genetic risk factors and assessed the therapeutic potential of a microRNA, miR-124-3p. Materials and methods: Bio-Plex Pro™ Human Chemokine analysis/qRT-PCR array was used for identification of deregulated immune genes. Sequencing/luciferase assay/ELISA detected and confirmed the polymorphisms. THP1 co-cultured with HepG2/LX2/HUVEC and apoptosis assay/qRT-PCR/neutrophil migration assay were employed as required. Results: The combined data analysis of the GSE143318/Bio-Plex Pro™ Human Chemokine array and qRT-PCR array revealed that six genes (TNFα/IL1ß/IL8/MCP1/IL6/TGFß) were commonly overexpressed in both serum/liver tissue of ALD-patients compared to ALC. The promoter sequence analysis of these 6 genes among ALD (n=322)/ALC (n=168) samples revealed that only two SNPs, rs361525(G/A) at -238 in TNF-α/rs1143627(C/T) at -31 in IL1ß were independently associated with ALD respectively. To evaluate the functional implication of these SNPs on ALD development, the serum level of TNF-α/IL1ß was verified and observed significantly higher in ALD patients with risk genotypes TNF-α-238GA/IL1ß-31CT+TT than TNF-α-238GG/IL1ß-31CC. The TNF-α/IL1ß promoter Luciferase-reporter assays showed significantly elevated level of luciferase activities with risk genotypes -238AA/-31TT than -238GG/-31CC respectively. Furthermore, treatment of conditioned medium of TNF-α/IL1ß over-expressed THP1 cells to HepG2/LX2/HUVEC cells independently showed enhanced level of ER stress and apoptosis in HepG2/increased TGFß and collagen-I production by LX2/huge neutrophil infiltration through endothelial layer. However, restoration of miR-124-3p in THP1 attenuated such inter-cellular communications and hepatocyte damage/collagen production/neutrophil infiltration were prohibited. Target analysis/luciferase-reporter assays revealed that both TNF-α/IL1ß were inhibited by miR-124-3p along with multiple genes from TLR4 signaling/apoptosis/fibrogenesis pathways including MYD88, TRAF3/TRADD, Caspase8/PDGFRA, TGFßR2/MCP1, and ICAM1 respectively. Conclusion: Thus, rs361525(G/A) in TNF-α and rs1143627(C/T) in IL1ß gene may be used as early predictors of ALD susceptibility among East Indian population. Impeding overexpressed TNF-α/IL1ß and various genes from associated immune response pathways, miR-124-3p exhibits robust therapeutic potential for ALD patients.


Assuntos
Interleucina-1beta , Hepatopatias Alcoólicas , MicroRNAs , Fator de Necrose Tumoral alfa , Humanos , Quimiocinas/genética , Colágeno/genética , Cirrose Hepática/genética , Hepatopatias Alcoólicas/genética , Luciferases/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Fator de Crescimento Transformador beta/genética , Fator de Necrose Tumoral alfa/genética , Interleucina-1beta/genética
7.
Asian J Neurosurg ; 18(3): 539-547, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38152526

RESUMO

Background Subthalamic deep brain stimulation (STN-DBS) for refractory Parkinson's disease (PD) is more of a modality of treatment that is empirical, for which a physiological explanation is being sought. This study was done to determine the outcome and complications of patients undergoing STN-DBS for PD. Methods This retrospective observational cohort study was conducted in an advanced neuromedicine facility in eastern India for 9 years (August 2013-August 2022), which included all patients undergoing STN-DBS. Results A total of 53 patients were operated on during the study period. The mean age group of the study population was 60.5 (standard deviation [SD]: 8.2) years with a male (33 [62.3%]) predominance. The most common presenting complaints included rigidity and hypokinesia (27), severe dyskinesia (21), and tremors (17). During the postoperative period, rigidity and hypokinesia (21), severe dyskinesia (16), and tremors (12) improved significantly in a subset of the patients. The majority (45 [84.9%]) of these cases received bilateral monopolar simulation, whereas three patients (5.7%) had bilateral bipolar stimulation. Unilateral bipolar stimulation was used in five (9.4%) patients. In the immediate postoperative period, they were initiated on limb, speech, and swallowing therapy as indicated. Surgery-related complications were seen in five (9.4%) cases. At 6 months of follow-up, a significant improvement in the Unified PD rating scale component (mainly motor examination and complication of PD therapy) was noted in the majority (36 [67.9%]) of patients. One patient developed neuroleptic malignant syndrome and succumbed to his illness on the fourth postoperative day. Conclusion Given these findings, STN-DBS appears to be a good, safe, and effective treatment for a subset of medically refractory PD with an overall improvement in two-thirds of the study cohort and less than 10% risk of complications.

8.
ACS Synth Biol ; 12(11): 3463-3481, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37852251

RESUMO

Green microalgae have emerged as beneficial feedstocks for biofuel production. A systems-level understanding of the biochemical network is needed to harness the microalgal metabolic capacity for bioproduction. Genome-scale metabolic modeling (GEM) showed immense potential in rational metabolic engineering, utilizing biochemical flux distribution analysis. Here, we report the first GEM for the green microalga, Scenedesmus obliquus (iAR632), a promising biodiesel feedstock with high lipid-storing capability. iAR632 comprises 1467 reactions, 734 metabolites, and 632 genes distributed among 7 compartments. The model was optimized under three different trophic modes of microalgal cultivation, i.e., autotrophy, mixotrophy, and heterotrophy. The robustness of the reconstructed network was confirmed by analyzing its sensitivity to the biomass components. Pathway-level flux profiles were analyzed, and significant flux space expansion was noticed majorly in reactions associated with lipid biosynthesis. In agreement with the experimental observation, iAR632 predicted about 3.8-fold increased biomass and almost 4-fold higher lipid under mixotrophy than the other trophic modes. Thus, the assessment of the condition-specific metabolic flux distribution of iAR632 suggested that mixotrophy is the preferred cultivation condition for improved microalgal growth and lipid production. Overall, the reconstructed GEM and subsequent analyses will provide a systematic framework for developing model-driven strategies to improve microalgal bioproduction.


Assuntos
Microalgas , Scenedesmus , Scenedesmus/genética , Scenedesmus/metabolismo , Biomassa , Microalgas/genética , Microalgas/metabolismo , Biocombustíveis , Lipídeos/genética
9.
J Prim Care Community Health ; 14: 21501319231197162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37665267

RESUMO

This commentary offers the reader an alternative to mentoring through the use of PODCASTS. By providing the listener with an understanding of the challenges and opportunities for self-reflection and sharing of experiences by the interviewees, we are impacting the listener attitudes and future goals through lessons learned.


Assuntos
Tutoria , Humanos , Doações , Avaliação de Programas e Projetos de Saúde , Mentores , Docentes
10.
J Phys Chem B ; 127(39): 8406-8416, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37751511

RESUMO

Deciphering the ionic liquid (IL) tolerance of glycoside hydrolases (GHs) to improve their hydrolysis efficiency for fermentable sugar synthesis in the "one-pot" process has long been a hurdle for researchers. In this work, we employed experimental and theoretical approaches to investigate the 1-ethyl-3-methylimidazolium acetate ([C2C1im][MeCO2])-induced inhibition of GH1 ß-glucosidase (H0HC94) from Agrobacterium tumefaciens 5A. At 10-15% [C2C1im][MeCO2] concentration, H0HC94 experiences competitive inhibition (R2 = 0.97, alpha = 2.8). As the IL content increased to 20-25%, the inhibition pattern shifted to mixed-type inhibition (R2 = 0.98, alpha = 3.4). These findings were further confirmed through characteristic inhibition plots using Lineweaver-Burk plots. Atomistic molecular dynamics simulations conducted with 0% [C2C1im][MeCO2], 10% [C2C1im][MeCO2], and 25% [C2C1im][MeCO2] revealed the accumulation of [C2C1im]+ at the negatively charged active site of H0HC94 in 10% [C2C1im][MeCO2], supporting the occurrence of competitive inhibition at lower IL concentrations. At higher IL concentrations, the cations and anions bound to the secondary binding sites (SBSs) of H0HC94, leading to a tertiary conformational change, as captured by the principal component analysis based on the free-energy landscape and protein structure networks. The altered conformation of H0HC94 affected the interaction with [C2C1im][MeCO2], which could possibly shift the inhibition from competitive to more mixed-type (competitive + noncompetitive) inhibition, as observed in the experiments. For the first time, we report a combined experimental and theoretical insight behind the mixed inhibition of a GH1 ß-glucosidase. Our findings indicated the role of SBS in IL-induced inhibition, which could aid in developing more IL-tolerant ß-glucosidases for biorefinery applications.

11.
Transfusion ; 63(9): 1747-1757, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37427683

RESUMO

BACKGROUND: Red Blood cells (RBCs) bring about harmful consequences during storage. MicroRNA (miRNA) dysregulation in stored RBCs could represent potential biomarkers of storage lesions. Although leukoreduction prevents damage to RBCs, it is uncertain whether leukoreduction of RBCs would impact the dysregulation of miRNAs during storage. This study evaluated the potential role of miRNAs for any alteration of leukoreduced (LR) and non-leukoreduced (NLR) RBCs till 21 days of storage. STUDY DESIGN AND METHODS: In this prospective study, thirty male volunteers' blood was equally divided into leukoreduced RBCs (LR) and NLR RBC (NLR) bags and stored till Day 21 at 4-60c. Selected miRNAs were quantified on Days 0 and 21. Further, bioinformatic tools were used to analyze the selected miRNAs and their predicted target genes (mRNAs) and identify the miRNA-mRNA regulatory relationships. RESULTS: A significantly higher fold change values of three miRNAs (miR-96-5p, miR-197-3p, miR-769-3p) were observed in NLR RBCs (p < .05). A significantly higher (p < .05) expression levels of miR-150-5p and miR-197-3p were observed in NLR RBCs till 21 days of storage. Further, the correlation with mRNA quantification confirmed the regulatory role of these miRNAs upon functional pathway enrichment analysis. DISCUSSION: A higher level of dysregulation of miRNAs was observed in NLR RBCs. Validation from In-Silico analysis suggested the regulatory role of miRNAs in cell apoptosis, senescence, and RBC-related signaling pathways. This indicated that stored LR RBCs would likely have better in vivo survival and function following transfusion. However, an in vivo study of miRNA in RBCs is warranted for conclusive evidence.


Assuntos
MicroRNAs , Humanos , Masculino , MicroRNAs/metabolismo , Preservação de Sangue , Estudos Prospectivos , Eritrócitos/metabolismo
12.
Cureus ; 15(3): e36813, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37123805

RESUMO

Background Although the association between the presence of diabetes mellitus and the development of deep vein thrombosis (DVT) is well known, the role of novel biomarkers in predicting the development of DVT in diabetic patients is not yet known to a large extent. Studies have shown that complete blood count (CBC) and CBC-derived parameters such as neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) can be used as surrogate markers to detect DVT. This study was conducted to assess the utility of NLR and PLR as a marker of DVT in diabetic patients. Methodology This case-control study was conducted among a calculated sample size of 109 DVT patients in one arm and 109 non-DVT patients in another arm. Hematological tests including total leucocyte count, differential leucocyte count, total neutrophil count, total lymphocyte count, total platelet count, NLR, and PLR were performed. Results We found a significant difference in NLR and PLR between the DVT and the non-DVT groups. In addition, we found that NLR and PLR were significantly higher in the diabetic group, indicating the presence of inflammation in association with diabetes mellitus. Analysis of the receiver operating characteristic curve showed that at a cut-off value of 2.83, NLR can detect DVT in diabetic patients with 67% sensitivity and 92% specificity. Similarly, PLR at a cut-off value of 131.46 can detect DVT in diabetic patients with 56% sensitivity and 90% specificity. Conclusions We conclude that NLR and PLR are novel inflammatory markers that can help in the early detection of DVT in diabetic patients.

13.
J Am Chem Soc ; 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36753330

RESUMO

A strategy for light-powered guest release from a tetrahedral capsule has been developed by incorporating azobenzene units at its vertices. A new Zn4L4 tetrahedral capsule bearing 12 diazo moieties at its metal-ion vertices was prepared from a phenyldiazenyl-functionalized subcomponent and a central trialdehyde panel. Ultraviolet irradiation caused isomerization of the peripheral diazo groups from the thermodynamically preferred trans configuration to the cis form, thereby generating steric clash and resulting in cage disassembly and concomitant guest release. Visible-light irradiation drove cage re-assembly following re-isomerization of the diazo groups to the trans form, resulting in guest re-uptake. A detailed 19F NMR study elucidated how switching led to guest release: each metal vertex tolerated only one cis-azobenzene moiety, with further isomerization leading to cage disassembly.

14.
Curr Mol Pharmacol ; 16(8): 915-926, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36809960

RESUMO

BACKGROUND: MicroRNAs (miRNA) are small non-coding RNAs that regulate the function of mRNA post-transcriptionally in a tissue-specific manner. miRNA expressions are heavily dysregulated in human cancer cells through various mechanisms, including epigenetic changes, karyotype abnormalities, and miRNA biogenesis defects. miRNAs may act as either oncogenes or tumor suppressors under different conditions. Epicatechin is a natural compound found in green tea which possesses antioxidant and antitumor properties. OBJECTIVE: The objective of this study is to investigate the effect of epicatechin treatment on the expression level of several oncogenic and tumor suppressor miRNAs in breast and colorectal cancer cell lines (MCF7 and HT-29) and identify its mechanism of action. METHODS: The MCF-7 and HT29 cells were treated with epicatechin for 24 hours and untreated cells were considered control cultures. miRNA was isolated and qRT-PCR was used to measure the expression profile changes of different oncogenic and tumor suppressor miRNAs. Furthermore, the mRNA expression profile was also screened at different concentrations of epicatechin. RESULTS: Our results showed several-fold changes in miRNAs expression level, which is cell line specific. Also, epicatechin at different concentrations induces biphasic changes in mRNA expression levels in both cell lines. CONCLUSION: Our findings first time demonstrated that epicatechin can reverse the expression of these miRNAs and may trigger the cytostatic effect at a lower concentration.


Assuntos
Neoplasias da Mama , Catequina , Neoplasias Colorretais , MicroRNAs , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Catequina/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética
15.
Comput Biol Med ; 154: 106600, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36739820

RESUMO

Specialized microbial communities in the fungus-farming termite gut and fungal comb microbiome help maintain host nutrition through interactive biochemical activities of complex carbohydrate degradation. Numerous research studies have been focused on identifying the microbial species in the termite gut and fungal comb microbiota, but the community-wide metabolic interaction patterns remain obscure. The inter-microbial metabolic interactions in the community environment are essential for executing biochemical processes like complex carbohydrate degradation and maintaining the host's physicochemical homeostasis. Recent progress in high-throughput sequencing techniques and mathematical modeling provides suitable platforms for constructing multispecies genome-scale community metabolic models that can render sound knowledge about microbial metabolic interaction patterns. Here, we have implemented the genome-scale metabolic modeling strategy to map the relationship between genes, proteins, and reactions of 12 key bacterial species from fungal cultivating termite gut and fungal comb microbiota. The resulting individual genome-scale metabolic models (GEMs) have been analyzed using flux balance analysis (FBA) to optimize the metabolic flux distribution pattern. Further, these individual GEMs have been integrated into genome-scale community metabolic models where a heuristics-based computational procedure has been employed to track the inter-microbial metabolic interactions. Two separate genome-scale community metabolic models were reconstructed for the O. badius gut and fungal comb microbiome. Analysis of the community models showed up to ∼167% increased flux range in lignocellulose degradation, amino acid biosynthesis, and nucleotide metabolism pathways. The inter-microbial metabolic exchange of amino acids, SCFAs, and small sugars was also upregulated in the multispecies community for maximum biomass formation. The flux variability analysis (FVA) has also been performed to calculate the feasible flux range of metabolic reactions. Furthermore, based on the calculated metabolic flux values, newly defined parameters, i.e., pairwise metabolic assistance (PMA) and community metabolic assistance (CMA) showed that the microbial species are getting up to 15% higher metabolic benefits in the multispecies community compared to pairwise growth. Assessment of the inter-microbial metabolic interaction patterns through pairwise growth support index (PGSI) indicated an increased mutualistic interaction in the termite gut environment compared to the fungal comb. Thus, this genome-scale community modeling study provides a systematic methodology to understand the inter-microbial interaction patterns with several newly defined parameters like PMA, CMA, and PGSI. The microbial metabolic assistance and interaction patterns derived from this computational approach will enhance the understanding of combinatorial microbial activities and may help develop effective synergistic microcosms to utilize complex plant polymers.


Assuntos
Fenômenos Bioquímicos , Microbioma Gastrointestinal , Isópteros , Animais , Isópteros/genética , Isópteros/metabolismo , Isópteros/microbiologia , Microbioma Gastrointestinal/genética , Interações Microbianas , Fungos/genética , Agricultura , Carboidratos
16.
Cancers (Basel) ; 15(3)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36765626

RESUMO

We previously reported that NOD.Scid mice lacking interleukin-15 (IL-15), or IL-15 receptor alpha-chain, develop T-acute lymphoblastic leukemia (T-ALL). To understand the mechanisms by which IL-15 signaling controls T-ALL development, we studied the thymocyte developmental events in IL-15-deficient Scid mice from NOD and C57BL/6 genetic backgrounds. Both kinds of mice develop T-ALL characterized by circulating TCR-negative cells expressing CD4, CD8 or both. Analyses of thymocytes in NOD.Scid.Il15-/- mice prior to T-ALL development revealed discernible changes within the CD4-CD8- double-negative (DN) thymocyte developmental stages and increased frequencies of CD4+CD8+ double-positive cells with a high proportion of TCR-negative CD4+ and CD8+ cells. The DN cells also showed elevated expressions of CXCR4 and CD117, molecules implicated in the expansion of DN thymocytes. T-ALL cell lines and primary leukemic cells from IL-15-deficient NOD.Scid and C57BL/6.Scid mice displayed increased NOTCH1 activation that was inhibited by NOTCH1 inhibitors and blockers of the PI3K/AKT pathway. Primary leukemic cells from NOD.Scid.Il15-/- mice survived and expanded when cultured with MS5 thymic stromal cells expressing Delta-like ligand 4 and supplemented with IL-7 and FLT3 ligand. These findings suggest that IL-15 signaling in the thymus controls T-ALL development from aberrant thymocytes with an impaired DNA repair capacity and increased NOTCH1 activation.

17.
Artigo em Inglês | MEDLINE | ID: mdl-36852811

RESUMO

BACKGROUND: Thrombotic disease is still a major killer. Aspirin, Ticagrelor, Clopidogrel, etc. are the most widely used conventional antiplatelet drugs. The significant number of patients who are resistant to this drug shows a poor outcome. OBJECTIVE: Developing a new antiplatelet agent with a stable antiplatelet effect and minimal bleeding risk is required for a patient who is resistant to antiplatelet drugs. METHOD: Protein-ligand docking was performed using Autodock Vina 1.1.2 to study the interaction of 67LR with different Polyphenols. RESULT: Among the 18 polyphenols, thearubigin has the highest binding affinity towards 67LR and gallic acid shows the lowest binding affinity. Among the 18 molecules, the top 10 molecules from the highest to lowest binding affinity range from-10.6 (thearubigin) to -6.5 (Epigallocatechin). CONCLUSION: Polyphenols may inhibit platelet aggregation through 67 LR and can be an alternative treatment for Thrombotic Disease. Moreover, it will be interesting to know whether polyphenols interfere with the same pathways as aspirin and clopidogrel. Effective polyphenols could help prototype the compound development of novel antiplatelet agents.

18.
PLoS One ; 18(1): e0280282, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36626386

RESUMO

Complement Receptor Type 1 (CR1) is a malaria-associated gene that encodes a transmembrane receptor of erythrocytes and is crucial for malaria parasite invasion. The expression of CR1 contributes to the rosetting of erythrocytes in the brain bloodstream, causing cerebral malaria, the most severe form of the disease. Here, we study the history of adaptation against malaria by analyzing selection signals in the CR1 gene. We used whole-genome sequencing datasets of 907 healthy individuals from malaria-endemic and non-endemic populations. We detected robust positive selection in populations from the hyperendemic regions of East India and Papua New Guinea. Importantly, we identified a new adaptive variant, rs12034598, which is associated with a slower rate of erythrocyte sedimentation and is linked with a variant associated with low levels of CR1 expression. The combination of the variants likely drives natural selection. In addition, we identified a variant rs3886100 under positive selection in West Africans, which is also related to a low level of CR1 expression in the brain. Our study shows the fine-resolution history of positive selection in the CR1 gene and suggests a population-specific history of CR1 adaptation to malaria. Notably, our novel approach using population genomic analyses allows the identification of protective variants that reduce the risk of malaria infection without the need for patient samples or malaria individual medical records. Our findings contribute to understanding of human adaptation against cerebral malaria.


Assuntos
Malária Cerebral , Receptores de Complemento 3b , Humanos , Eritrócitos , Malária Cerebral/genética , Malária Cerebral/metabolismo , Papua Nova Guiné , Receptores de Complemento 3b/genética , Seleção Genética , Genética Populacional , Índia
19.
Indian J Otolaryngol Head Neck Surg ; 75(Suppl 1): 320-329, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36628335

RESUMO

To analyze the socio-demographic and audiological profile of the applicants for hearing handicap certification in the Medical Board (henceforth, "Board") of a tertiary care teaching institute. This is a retrospective record review (March 2019-February 2020) from the archival computer database of the institutional Board. The procedure for audiological assessment prior to Board review and thereafter, the evaluation at the Board (computation of hearing impairment) for eligibility for certification was discussed. The socio-demographic profile of the applicants (age, gender, faith) and the types of hearing impairment [HI%; organic (sensorineural, mixed), non-organic (malingering)] were analyzed with relevant statistical parameters. A HI% scale was introduced to classify the severity of the hearing deficit. Of the 163 applicants, 148 had organic hearing loss (average age: 35.4 years; 1.9 times male preponderance) and 15 were malingerers (average age: 35.7 years; 14 times male preponderance). The left ear contributed more to the hearing handicap. Most applicants having sensorineural hearing loss (SNHL; n = 124) were within 10-19 years and 40-49 years (19.35% each), with 12% being ≧ 60 years (age-associated hearing loss). Of the 13 applicants of age ≦ 12 years, eight were diagnosed with brainstem evoked response audiometry, and 10 had HI score of ≥ 70%. Muslim population with SNHL tended to avail certification 1.34 times more than the Hindus. Most of the applicants with mixed hearing loss (MHL; n = 24) were in their fifth and sixth decades (29.2% each), with three times male preponderance. Among the malingerers, the average malingering impairment was 66% (median: 61%; range 44-100%). Among the SNHL population, ~ 30% had HI at 90-100% in contrast to the MHL population of whom 8% had HI at > 90% and 29% had HI at 40- < 55%. Ten applicants among the organic hearing loss group (6.76%) (two with SNHL; eight with MHL) had HI scores of < 40% and were considered ineligible for certification. The outcomes of the review provided a comprehensive account of the socio-demographic profile of the applicants for handicap certification and the type of hearing loss prevailing in a given population. These data, and the severity stratification of the hearing disability through the HI% scale would provide the policymakers and stakeholders with proper directions to work upon.

20.
Biotechnol Adv ; 62: 108069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36442697

RESUMO

Metabolic engineering encompasses several widely-used strategies, which currently hold a high seat in the field of biotechnology when its potential is manifesting through a plethora of research and commercial products with a strong societal impact. The genomic revolution that occurred almost three decades ago has initiated the generation of large omics-datasets which has helped in gaining a better understanding of cellular behavior. The itinerary of metabolic engineering that has occurred based on these large datasets has allowed researchers to gain detailed insights and a reasonable understanding of the intricacies of biosystems. However, the existing trail-and-error approaches for metabolic engineering are laborious and time-intensive when it comes to the production of target compounds with high yields through genetic manipulations in host organisms. Machine learning (ML) coupled with the available metabolic engineering test instances and omics data brings a comprehensive and multidisciplinary approach that enables scientists to evaluate various parameters for effective strain design. This vast amount of biological data should be standardized through knowledge engineering to train different ML models for providing accurate predictions in gene circuits designing, modification of proteins, optimization of bioprocess parameters for scaling up, and screening of hyper-producing robust cell factories. This review briefs on the premise of ML, followed by mentioning various ML methods and algorithms alongside the numerous omics datasets available to train ML models for predicting metabolic outcomes with high-accuracy. The combinative interplay between the ML algorithms and biological datasets through knowledge engineering have guided the recent advancements in applications such as CRISPR/Cas systems, gene circuits, protein engineering, metabolic pathway reconstruction, and bioprocess engineering. Finally, this review addresses the probable challenges of applying ML in metabolic engineering which will guide the researchers toward novel techniques to overcome the limitations.


Assuntos
Biotecnologia , Engenharia Metabólica , Engenharia Metabólica/métodos , Sistemas CRISPR-Cas , Engenharia de Proteínas , Aprendizado de Máquina
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