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1.
Pancreatology ; 24(4): 608-615, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38749803

RESUMO

BACKGROUND: Acute cholangitis (AC) is a common complication of pancreatic ductal adenocarcinoma (PDAC). Herein, we evaluated outcomes after the first AC episode and predictors of mortality and AC recurrence in patients with stage IV PDAC. METHODS: We conducted a single-center, retrospective observational study using institutional databases. Clinical data and outcomes for patients with stage IV PDAC and at least one documented episode of AC, were assessed. Overall survival (OS) was estimated using the Kaplan-Meier method, and Cox regression model was employed to identify predictors of AC recurrence and mortality. RESULTS: One hundred and twenty-four patients with stage IV PDAC and AC identified between January 01, 2014 and October 31, 2020 were included. Median OS after first episode of AC was 4.1 months (95 % CI, 4.0-5.5), and 30-day, 6, and 12-month survival was 86.2 % (95 % CI, 80.3-92.5), 37 % (95 % CI, 29.3-46.6 %) and 18.9 % (95 % CI, 13.1-27.3 %), respectively. Primary tumor in pancreatic body/tail (HR 2.29, 95 % CI: 1.26 to 4.18, p = 0.011), concomitant metastases to liver and other sites (HR 1.96, 95 % CI: 1.16 to 3.31, p = 0.003) and grade 3 AC (HR 2.26, 95 % CI: 1.45 to 3.52, p < 0.001), predicted worse outcomes. Intensive care unit admission, sepsis, systemic therapy, treatment regimen, and time to intervention did not predict survival or risk of recurrence of AC. CONCLUSIONS: AC confers significant morbidity and mortality in advanced PDAC. Worse outcomes are associated with higher grade AC, primary tumor location in pancreatic body/tail, and metastases to liver and other sites.


Assuntos
Colangite , Neoplasias Pancreáticas , Humanos , Colangite/complicações , Colangite/mortalidade , Masculino , Feminino , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/patologia , Idoso , Estudos Retrospectivos , Pessoa de Meia-Idade , Prognóstico , Estadiamento de Neoplasias , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/complicações , Carcinoma Ductal Pancreático/patologia , Idoso de 80 Anos ou mais , Adenocarcinoma/mortalidade , Adenocarcinoma/complicações , Adenocarcinoma/patologia , Doença Aguda , Fatores de Risco
2.
Antib Ther ; 7(1): 37-52, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38235376

RESUMO

Multispecific antibodies recognize two or more epitopes located on the same or distinct targets. This added capability through protein design allows these man-made molecules to address unmet medical needs that are no longer possible with single targeting such as with monoclonal antibodies or cytokines alone. However, the approach to the development of these multispecific molecules has been met with numerous road bumps, which suggests that a new workflow for multispecific molecules is required. The investigation of the molecular basis that mediates the successful assembly of the building blocks into non-native quaternary structures will lead to the writing of a playbook for multispecifics. This is a must do if we are to design workflows that we can control and in turn predict success. Here, we reflect on the current state-of-the-art of therapeutic biologics and look at the building blocks, in terms of proteins, and tools that can be used to build the foundations of such a next-generation workflow.

3.
J Pharm Bioallied Sci ; 15(Suppl 1): S248-S251, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37654417

RESUMO

Aim: The purpose of this study was to assess the short-term perioral soft tissue variations of the lips before and after treatment cases in 15 patients with bi-maxillary protrusion using treated lateral cephalograms who had already achieved active growth. Methodology: Fifteen pre-treatment and post-treatment lateral cephalometric radiographs of 18-25-year-old individuals with bimaxillary protrusion treated with all four 1st premolar extractions were accessed from the records. From the reference planes and landmarks, 13 horizontal, 10 vertical, and 2 angular measurements were noted. Statistical comparisons between pre-treatment and post-treatment measurements were measured by a paired t-test to assess the importance of the mean variations at the predetermined significance level. Pearson's correlation coefficient (R) was utilized to assess the strength and significance of the linear relationship between the mean differences for paired (dependent and independent) variables. Results: Pearson's correlation exhibited a noteworthy positive association between the horizontal changes in upper lip position and the horizontal changes of the upper incisor tip point (H-tU1) (R = 0.748), the upper incisor cervical point (H-cU1) (R = 0.707), the lower incisor tip point (H-tL1) (R = 0.839), and the lower incisor cervical point (H-cL1) (R = 0.767). This indicated that upper lip changes are the aftermath of the retraction of the upper and lower incisors in class I bi-maxillary protrusion malocclusion. Conclusion: Thick upper lips showed more retraction of the upper lip in correlation with retraction of the incisors as compared with thin lips. The lower incisor cervical point displayed the strongest association with lower lip retraction.

4.
J Conserv Dent Endod ; 26(4): 388-394, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37705556

RESUMO

Aim: Assessment of remineralizing agent's effect on laser and nonlaser bleached enamel surfaces subjected to erosion. Materials and Methods: In this study, 80 extracted human permanent anteriors were collected and divided into 4 groups with 20 teeth per sample. Enamel specimen of 3 mm × 3 mm were made using polyvinyl chloride rings and acrylic and randomly divided into four groups. Then the specimens were subjected to initial microhardness test using Vicker's hardness tester (AVK-CO, Mitutoyo, Japan). Two indentations were placed at 100 mm from one another in the center of all the samples. Bleaching with laser and without laser using hydrogen peroxide was performed followed by remineralization in the groups (Groups 1a and 2a) and then were subjected to erosion. The final hardness was measured using the above method used for initial microhardness. Results: Microhardness in the remineralized groups showed least variation. The group in which laser bleaching was performed along with remineralization as compared with nonlaser bleaching group with remineralization showed improvement in microhardness but the data was not statistically significant. A significant difference was noted between the laser and remineralization group when compared with the groups in which no remineralization was done. Conclusion: After bleaching the enamel surface is more prone to erosion, so to improve the microhardness of bleached enamel a remineralizing agent should be used. A combination of diode laser bleaching and remineralizing agents leads to improved microhardness of the bleached enamel thus proving this combination to be efficacious.

5.
Protein Sci ; 32(8): e4712, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37354015

RESUMO

Antiviral therapeutics to treat SARS-CoV-2 are needed to diminish the morbidity of the ongoing COVID-19 pandemic. A well-precedented drug target is the main viral protease (MPro ), which is targeted by an approved drug and by several investigational drugs. Emerging viral resistance has made new inhibitor chemotypes more pressing. Adopting a structure-based approach, we docked 1.2 billion non-covalent lead-like molecules and a new library of 6.5 million electrophiles against the enzyme structure. From these, 29 non-covalent and 11 covalent inhibitors were identified in 37 series, the most potent having an IC50 of 29 and 20 µM, respectively. Several series were optimized, resulting in low micromolar inhibitors. Subsequent crystallography confirmed the docking predicted binding modes and may template further optimization. While the new chemotypes may aid further optimization of MPro inhibitors for SARS-CoV-2, the modest success rate also reveals weaknesses in our approach for challenging targets like MPro versus other targets where it has been more successful, and versus other structure-based techniques against MPro itself.


Assuntos
COVID-19 , Humanos , SARS-CoV-2/metabolismo , Pandemias , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Simulação de Acoplamento Molecular , Proteínas não Estruturais Virais/química , Antivirais/farmacologia , Antivirais/química
6.
J Med Chem ; 66(12): 7785-7803, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37294077

RESUMO

An under-explored target for SARS-CoV-2 is the S-adenosyl methionine (SAM)-dependent methyltransferase Nsp14, which methylates the N7-guanosine of viral RNA at the 5'-end, allowing the virus to evade host immune response. We sought new Nsp14 inhibitors with three large library docking strategies. First, up to 1.1 billion lead-like molecules were docked against the enzyme's SAM site, leading to three inhibitors with IC50 values from 6 to 50 µM. Second, docking a library of 16 million fragments revealed 9 new inhibitors with IC50 values from 12 to 341 µM. Third, docking a library of 25 million electrophiles to covalently modify Cys387 revealed 7 inhibitors with IC50 values from 3.5 to 39 µM. Overall, 32 inhibitors encompassing 11 chemotypes had IC50 values < 50 µM and 5 inhibitors in 4 chemotypes had IC50 values < 10 µM. These molecules are among the first non-SAM-like inhibitors of Nsp14, providing starting points for future optimization.


Assuntos
COVID-19 , Metiltransferases , Humanos , SARS-CoV-2/genética , Proteínas não Estruturais Virais/genética , RNA Viral/genética , Exorribonucleases
7.
Cell ; 186(10): 2160-2175.e17, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37137306

RESUMO

The serotonin transporter (SERT) removes synaptic serotonin and is the target of anti-depressant drugs. SERT adopts three conformations: outward-open, occluded, and inward-open. All known inhibitors target the outward-open state except ibogaine, which has unusual anti-depressant and substance-withdrawal effects, and stabilizes the inward-open conformation. Unfortunately, ibogaine's promiscuity and cardiotoxicity limit the understanding of inward-open state ligands. We docked over 200 million small molecules against the inward-open state of the SERT. Thirty-six top-ranking compounds were synthesized, and thirteen inhibited; further structure-based optimization led to the selection of two potent (low nanomolar) inhibitors. These stabilized an outward-closed state of the SERT with little activity against common off-targets. A cryo-EM structure of one of these bound to the SERT confirmed the predicted geometry. In mouse behavioral assays, both compounds had anxiolytic- and anti-depressant-like activity, with potencies up to 200-fold better than fluoxetine (Prozac), and one substantially reversed morphine withdrawal effects.


Assuntos
Ibogaína , Inibidores Seletivos de Recaptação de Serotonina , Proteínas da Membrana Plasmática de Transporte de Serotonina , Bibliotecas de Moléculas Pequenas , Animais , Camundongos , Fluoxetina/farmacologia , Ibogaína/química , Ibogaína/farmacologia , Conformação Molecular , Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/química , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/ultraestrutura , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia
8.
Nature ; 609(7928): 846-853, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35940205

RESUMO

Thyroid hormones are vital in metabolism, growth and development1. Thyroid hormone synthesis is controlled by thyrotropin (TSH), which acts at the thyrotropin receptor (TSHR)2. In patients with Graves' disease, autoantibodies that activate the TSHR pathologically increase thyroid hormone activity3. How autoantibodies mimic thyrotropin function remains unclear. Here we determined cryo-electron microscopy structures of active and inactive TSHR. In inactive TSHR, the extracellular domain lies close to the membrane bilayer. Thyrotropin selects an upright orientation of the extracellular domain owing to steric clashes between a conserved hormone glycan and the membrane bilayer. An activating autoantibody from a patient with Graves' disease selects a similar upright orientation of the extracellular domain. Reorientation of the extracellular domain transduces a conformational change in the seven-transmembrane-segment domain via a conserved hinge domain, a tethered peptide agonist and a phospholipid that binds within the seven-transmembrane-segment domain. Rotation of the TSHR extracellular domain relative to the membrane bilayer is sufficient for receptor activation, revealing a shared mechanism for other glycoprotein hormone receptors that may also extend to other G-protein-coupled receptors with large extracellular domains.


Assuntos
Microscopia Crioeletrônica , Imunoglobulinas Estimuladoras da Glândula Tireoide , Receptores da Tireotropina , Tireotropina , Membrana Celular/metabolismo , Doença de Graves/imunologia , Doença de Graves/metabolismo , Humanos , Imunoglobulinas Estimuladoras da Glândula Tireoide/química , Imunoglobulinas Estimuladoras da Glândula Tireoide/imunologia , Imunoglobulinas Estimuladoras da Glândula Tireoide/farmacologia , Imunoglobulinas Estimuladoras da Glândula Tireoide/ultraestrutura , Fosfolipídeos/metabolismo , Domínios Proteicos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/ultraestrutura , Receptores da Tireotropina/agonistas , Receptores da Tireotropina/química , Receptores da Tireotropina/imunologia , Receptores da Tireotropina/ultraestrutura , Rotação , Tireotropina/química , Tireotropina/metabolismo , Tireotropina/farmacologia
9.
Monaldi Arch Chest Dis ; 93(1)2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35723643

RESUMO

Pulmonary rehabilitation (PR) is being used in the routine management of patients of obstructive sleep apnea (OSA) at some centers. However, the studies documenting benefits of PR in OSA lack standardization in terms of outcome measures. A study was hence planned to determine the efficacy of PR on exercise capacity, health related quality of life (HRQOL), day time sleepiness and sleep-quality of life (QOL) in patients of OSA. As a part of comprehensive therapy, patients diagnosed with OSA are managed with continuous positive airway pressure (CPAP), 8 weeks thrice weekly outpatient hospital-based PR and medical treatment at the Pulmonary Medicine Department, Government Medical College and Hospital, Chandigarh. However, some patients refuse for PR because of time constraints and travel issues. Patients with newly diagnosed OSA without co-existing respiratory disease, who agreed for the CPAP, PR and medical management were enrolled in group A. The patients who refused for PR but were ready for CPAP and medical management were enrolled in Group B; 30 patients were taken in each group. Exercise capacity, HRQOL, day time sleepiness and sleep-QOL were determined at baseline and at 8-weeks follow-up by 6-minute walk distance (6MWD), St. George's Respiratory Questionnaire (SGRQ), Epworth Sleepiness Scale (ESS) and Functional Outcomes of Sleep Questionnaire (FOSQ) and compared amongst the two groups. Four patients from group A were excluded as they did not complete PR; 26 patients from group A and 30 patients from group B were finally analyzed. At baseline, both groups were matched with respect to age, gender, apnea-hypopnea index (AHI), body mass index (BMI), FEV1%predicted, 6MWD, SGRQ, ESS and FOSQ. At follow up at 8 weeks, BMI, 6MWD, SGRQ, ESS and FOSQ improved significantly from baseline in group A (p<0.001). FEV1%predicted also improved but non significantly. In group B, FEV1%predicted, BMI, 6MWD, SGRQ, ESS and FOSQ score did not improve significantly from baseline. Mean improvement from baseline in BMI, 6MWD, SGRQ, ESS and FOSQ was significantly more in group A than group B (p<0.001, p<0.001, p=0.041, p<0.001 and p<0.001, respectively). PR, being beneficial, should be incorporated in standard management of OSA.


Assuntos
Qualidade de Vida , Apneia Obstrutiva do Sono , Humanos , Resultado do Tratamento , Sonolência , Apneia Obstrutiva do Sono/terapia , Apneia Obstrutiva do Sono/diagnóstico , Avaliação de Resultados em Cuidados de Saúde
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 280: 121530, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-35752037

RESUMO

The present work encompasses a combined experimental and theoretical investigation of the molecular structure, vibrational wavenumbers, electronic structure at the ground and electronic excited states, molecular electrostatic potential surface of 7-(Trifluoromethyl)-1H-indole-2-carboxylic acid (TICA) and possibility of the title molecule as an aromatase inhibitor using molecular docking and molecular dynamic simulations. A stable conformer has been obtained using potential energy scans by varying appropriate dihedral angles. The obtained minimum energy conformer was further optimized at the 6-311++G (d, p) basis set by applying the most accepted B3LYP functional. A good agreement between experimental and calculated normal modes of vibration has been observed. The hydrogen-bonded interaction between two monomeric units of TICA has been investigated using NBO,QTAIM, and NCI (noncovalent interactions) analysis. Molecular docking of TICA with human placental aromatase (PDB ID: 3S79) reveals the formation of polar hydrogen bonds as well as hydrophobic interactions between the ligand and the protein, right in the binding cavity. TICA satisfies all pharmacokinetic filters (Lipinski rule of five, the Veber rule, Ghose rule, Egan rule, as well as the Muegge rule) and has a high bioavailability score of 0.85. Dynamic stability of the ligand within the binding pocket of the target protein has been confirmed by 100 ns molecular dynamics simulation results. The present study provides an excellent starting point for additional in vivo research, and TICA may eventually serve as a significant therapeutic candidate for the treatment of breast cancer.


Assuntos
Inibidores da Aromatase , Simulação de Dinâmica Molecular , Ácidos Carboxílicos , Eletrônica , Feminino , Humanos , Indóis , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular , Placenta , Gravidez , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termodinâmica , Vibração
11.
Front Cell Dev Biol ; 9: 755751, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34938732

RESUMO

Testis-specific histone variants are crucial to promote open chromatin structure to enable nucleosome disassembly in the final stages of spermiogenesis. However, even after histone replacement, mature sperm retain a proportion of these variants, the function of which is unknown. The present study aimed to understand the functional relevance of the retained H2B and H2A variants, TH2B and TH2A. While no literature is available on the phenotype of TH2A knockouts, TH2B/TH2A double knockout male mice are reported to be infertile. In this study, ChIP-seq analysis was done for TH2B and TH2A to understand the epigenomics of the retained TH2B and TH2A, using murine caudal sperm. Distribution across genomic partitions revealed ∼35% of the TH2B peaks within ±5 kb of TSS whereas TH2A peaks distribution was sparse at TSS. Gene Ontology revealed embryo development as the most significant term associated with TH2B. Also, based on genomic regions, TH2B was observed to be associated with spindle assembly and various meiosis-specific genes, which is an important finding as TH2A/TH2B DKO mice have been reported to have defective cohesin release. A comparison of mouse and human TH2B-linked chromatin revealed 26% overlap between murine and human TH2B-associated genes. This overlap included genes crucial for embryogenesis. Most importantly, heterogeneity in the epigenetic landscape of TH2A and TH2B was seen, which is intriguing as TH2B and TH2A are well reported to be present in the same nucleosomes to promote open chromatin. Additionally, unlike TH2B, TH2A was enriched on the mitochondrial chromosome. TH2A was found to be associated with Nuclear insertion of Mitochondrial DNA sequences (NUMTs) in sperm. A comprehensive analysis of these observations indicates novel functions for the sperm-retained TH2B and TH2A.

12.
Nature ; 600(7887): 170-175, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34789874

RESUMO

The MRGPRX family of receptors (MRGPRX1-4) is a family of mas-related G-protein-coupled receptors that have evolved relatively recently1. Of these, MRGPRX2 and MRGPRX4 are key physiological and pathological mediators of itch and related mast cell-mediated hypersensitivity reactions2-5. MRGPRX2 couples to both Gi and Gq in mast cells6. Here we describe agonist-stabilized structures of MRGPRX2 coupled to Gi1 and Gq in ternary complexes with the endogenous peptide cortistatin-14 and with a synthetic agonist probe, respectively, and the development of potent antagonist probes for MRGPRX2. We also describe a specific MRGPRX4 agonist and the structure of this agonist in a complex with MRGPRX4 and Gq. Together, these findings should accelerate the structure-guided discovery of therapeutic agents for pain, itch and mast cell-mediated hypersensitivity.


Assuntos
Microscopia Crioeletrônica , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/química , Prurido/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/química , Receptores de Neuropeptídeos/antagonistas & inibidores , Receptores de Neuropeptídeos/química , Agonismo Inverso de Drogas , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/química , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/ultraestrutura , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/química , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/ultraestrutura , Humanos , Modelos Moleculares , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/ultraestrutura , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/ultraestrutura , Receptores de Neuropeptídeos/metabolismo , Receptores de Neuropeptídeos/ultraestrutura
13.
Artigo em Inglês | MEDLINE | ID: mdl-34476331

RESUMO

PURPOSE: In pancreatic cancer (PC), the RAF family alterations define a rare subset of patients that may predict response to inhibition of the BRAF/MEK/ERK signaling pathway. A comprehensive understanding of the molecular and clinical characteristics of RAF-mutated PC may support future development of RAF-directed strategies. METHODS: Clinical outcomes were assessed across a multi-institutional case series of 81 patients with RAF family-mutated PC. Mutational subgroups were defined on the basis of RAF alteration hotspots and therapeutic implications. RESULTS: The frequency of RAF alterations in PC was 2.2% (84 of 3,781) within a prevalence cohort derived from large molecular databases where BRAF V600E (Exon 15), BRAF ΔNVTAP (Exon 11), and SND1-BRAF fusions were the most common variants. In our retrospective case series, we identified 17 of 81 (21.0%) molecular profiles with a BRAF V600/Exon 15 mutation without any confounding drivers, 25 of 81 (30.9%) with BRAF or RAF1 fusions, and 18 of 81 (22.2%) with Exon 11 mutations. The remaining 21 of 81 (25.9%) profiles had atypical RAF variants and/or multiple oncogenic drivers. Clinical benefit from BRAF/MEK/ERK inhibitors was observed in 3 of 3 subjects within the V600 subgroup (two partial responses), 4 of 6 with fusions (two partial responses), 2 of 6 with Exon 11 mutations (one partial response), and 0 of 3 with confounding drivers. Outcomes analyses also suggested a trend favoring fluorouracil-based regimens over gemcitabine/nab-paclitaxel within the fusion subgroup (P = .027). CONCLUSION: Prospective evaluation of RAF-directed therapies is warranted in RAF-mutated PC; however, differential responses to targeted agents or standard regimens for each mutational subgroup should be a consideration when designing clinical trials.


Assuntos
Sistema de Sinalização das MAP Quinases/genética , Neoplasias Pancreáticas/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Idoso , Éxons/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidade , Proteínas Proto-Oncogênicas B-raf/metabolismo , Estudos Retrospectivos , Análise de Sobrevida
14.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34475217

RESUMO

Protein flexibility remains a major challenge in library docking because of difficulties in sampling conformational ensembles with accurate probabilities. Here, we use the model cavity site of T4 lysozyme L99A to test flexible receptor docking with energy penalties from molecular dynamics (MD) simulations. Crystallography with larger and smaller ligands indicates that this cavity can adopt three major conformations: open, intermediate, and closed. Since smaller ligands typically bind better to the cavity site, we anticipate an energy penalty for the cavity opening. To estimate its magnitude, we calculate conformational preferences from MD simulations. We find that including a penalty term is essential for retrospective ligand enrichment; otherwise, high-energy states dominate the docking. We then prospectively docked a library of over 900,000 compounds for new molecules binding to each conformational state. Absent a penalty term, the open conformation dominated the docking results; inclusion of this term led to a balanced sampling of ligands against each state. High ranked molecules were experimentally tested by Tm upshift and X-ray crystallography. From 33 selected molecules, we identified 18 ligands and determined 13 crystal structures. Most interesting were those bound to the open cavity, where the buried site opens to bulk solvent. Here, highly unusual ligands for this cavity had been predicted, including large ligands with polar tails; these were confirmed both by binding and by crystallography. In docking, incorporating protein flexibility with thermodynamic weightings may thus access new ligand chemotypes. The MD approach to accessing and, crucially, weighting such alternative states may find general applicability.


Assuntos
Proteínas/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Cinética , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica , Proteínas/química , Estudos Retrospectivos , Termodinâmica
15.
J Natl Cancer Inst ; 113(9): 1194-1202, 2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-33755158

RESUMO

BACKGROUND: Recent evidence suggests a rising incidence of cancer in younger individuals. Herein, we report the epidemiologic, pathologic, and molecular characteristics of a patient cohort with early-onset pancreas cancer (EOPC). METHODS: Institutional databases were queried for demographics, treatment history, genomic results, and outcomes. Overall survival from date of diagnosis was estimated using Kaplan-Meier method. RESULTS: Between 2008 and 2018, 450 patients with EOPC were identified at Memorial Sloan Kettering. Median overall survival was 16.3 (95% confidence interval [CI] = 14.6 to 17.7) months in the entire cohort and 11.3 (95% CI = 10.2 to 12.2) months for patients with stage IV disease at diagnosis. Of the patients, 132 (29.3% of the cohort) underwent somatic testing; 21 of 132 (15.9%) had RAS wild-type cancers with identification of several actionable alterations, including ETV6-NTRK3, TPR-NTRK1, SCLA5-NRG1, and ATP1B1-NRG1 fusions, IDH1 R132C mutation, and mismatch repair deficiency. A total of 138 patients (30.7% of the cohort) underwent germline testing; 44 of 138 (31.9%) had a pathogenic germline variant (PGV), and 27.5% harbored alterations in cancer susceptibility genes. Of patients seen between 2015 and 2018, 30 of 193 (15.5%) had a PGV. Among 138 who underwent germline testing, those with a PGV had a reduced all-cause mortality compared with patients without a PGV controlling for stage and year of diagnosis (hazard ratio = 0.42, 95% CI = 0.26 to 0.69). CONCLUSIONS: PGVs are present in a substantial minority of patients with EOPC. Actionable somatic alterations were identified frequently in EOPC, enriched in the RAS wild-type subgroup. These observations underpin the recent guidelines for universal germline testing and somatic profiling in pancreatic ductal adenocarcinoma.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/epidemiologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/terapia , Estudos de Coortes , Genômica , Humanos , Incidência , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia
16.
Plants (Basel) ; 9(12)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33316874

RESUMO

Kalmegh (Andrographis paniculata (Burm. F.) Nees) is one of the most important medicinal plants and has been widely explored as traditional medicine. To exploit its natural genetic diversity and initiations of molecular breeding to develop novel cultivars or varieties, developments of genomic resources are essential. Four microsatellite-enriched genomic libraries-(CT)14, (GT)12, (AG)15 and (AAC)8-were constructed using the genomic DNA of A. paniculata. Initially, 183 recombinant colonies were screened for the presence of CT, GT, AG, and AAC microsatellite repeats, out of which 47 clones found positive for the desired simple sequence repeats (SSRs). It was found that few colonies had more than one desirable SSR. Thus, a sum of 67 SSRs were designed and synthesized for their validation among 42 A. paniculata accessions. Out of the 67 SSRs used for genotyping, only 41 were found to be polymorphic. The developed set of g-SSR markers showed substantial genetic variability among the selected A. paniculata accessions, with an average polymorphic information content (PIC) value of 0.32. Neighbor-joining tree analysis, population structure analysis, analysis of molecular variance (AMOVA), and principal coordinate analysis (PCoA) illustrated the considerable genetic diversity among them. The novel g-SSR markers developed in the present study could be important genomic resources for future applications in A. paniculata.

17.
ACS Omega ; 5(46): 30073-30087, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33251442

RESUMO

Extensive investigation on the molecular and electronic structure of 2-amino-5-trifluoromethyl-1,3,4-thiadiazole in the ground state and in the first excited state has been performed. The energy barrier corresponding to the conversion between imino and amino tautomers has been calculated, which indicates the existence of amino tautomer in solid state for the title compound. The FT-Raman and FT-IR spectra were recorded and compared with theoretical vibrational wavenumbers, and a good coherence has been observed. The MESP map, dipole moment, polarizability, and hyperpolarizability have been calculated to comprehend the properties of the title molecule. High polarizability value estimation of the title compound may enhance its bioactivity. Natural bonding orbital analysis has been done on monomer and dimer to investigate the charge delocalization and strength of hydrogen bonding, respectively. Strong hydrogen bonding interaction energies of 17.09/17.49 kcal mol-1 have been calculated at the B3LYP/M06-2X functional. The UV-vis spectrum was recorded and related to the theoretical spectrum. The title compound was biologically examined for anticancer activity by studying the cytotoxic performance against two human cancer cell lines (A549 and HeLa) along with the molecular docking simulation. Both molecular docking and cytotoxic performance against cancer cell lines show positive outcomes, and the title compound appears to be a promising anticancer agent.

18.
PLoS One ; 15(8): e0237457, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32780764

RESUMO

Onion (Allium cepa L.) is an important vegetable crop widely grown for diverse culinary and nutraceutical properties. Being a shallow-rooted plant, it is prone to drought. In the present study, transcriptome sequencing of drought-tolerant (1656) and drought-sensitive (1627) onion genotypes was performed to elucidate the molecular basis of differential response to drought stress. A total of 123206 and 139252 transcripts (average transcript length: 690 bases) were generated after assembly for 1656 and 1627, respectively. Differential gene expression analyses revealed upregulation and downregulation of 1189 and 1180 genes, respectively, in 1656, whereas in 1627, upregulation and downregulation of 872 and 1292 genes, respectively, was observed. Genes encoding transcription factors, cytochrome P450, membrane transporters, and flavonoids, and those related to carbohydrate metabolism were found to exhibit a differential expression behavior in the tolerant and susceptible genotypes. The information generated can facilitate a better understanding of molecular mechanisms underlying drought response in onion.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Cebolas/genética , Metabolismo dos Carboidratos/genética , Perfilação da Expressão Gênica/métodos , Genótipo , Proteínas de Membrana Transportadoras/genética , RNA de Plantas/química , RNA de Plantas/metabolismo , Fatores de Transcrição/genética
19.
Indian J Tuberc ; 67(1): 3-7, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32192614

RESUMO

BACKGROUND/AIMS: The association between tuberculosis (TB) and female reproductive health issues usually remains unaddressed. TB is considered as one of the major causes of infertility in India. Because of the associated stigma, the suffering females do not discuss the problems they are facing. This may lead to disturbances in serum hormone levels also. Hence, a study was planned to find abnormalities in menstrual patterns and fertility in women in childbearing age, who were suffering from TB, and evaluate disturbances in serum hormone levels of LH, FSH, Prolactin and testosterone, if any. It also aimed to evaluate if hormone levels, or some early disturbances in menstrual cycle, can serve as a predictor for infertility in future lives. MATERIALS AND METHODS: 25 female patients each of child bearing age group from OPD/IPD: of pulmonary TB (PTB), extra pulmonary non genital TB (EPTB), extra pulmonary genital TB (GTB) and healthy controls were enrolled. Thus, a total of 75 patients with TB and 25 healthy controls were taken into the study. Patients were questioned for any abnormalities of menstrual cycle. If married, fertility status, total number of live children, abortions etc and previous history of any reproductive health issues was asked. Serum FSH, LH, Prolactin and testosterone levels on the 3rd day of the menstrual cycle were done. Data so obtained was tabulated and statistically analyzed. RESULTS: TB patients (75/100) and healthy controls (25/100) were matched with respect to age, marital status and rural/urban background. Menstrual abnormalities, infertility and adverse events related to pregnancy were higher in patients with TB than healthy controls (p = 0.176, 0.571 and 0.005 respectively). TB patients had significantly higher levels of Testosterone and significantly lower levels of Prolactin than healthy controls (p=<0.001). Levels of FSH and LH were lower in TB patients than healthy controls (p = 0.428 and 0.274 respectively). On categorization into different types of TB, the sub-groups were matched with respect to rural/urban background. GTB was significantly higher in patients who were married (p = 0.020). Significantly higher GTB patients (10/25) reported menstrual abnormalities (p < 0.001). All the 3 infertile patients reported in the study belonged to GTB sub-group (p = 0.044). GTB had higher number of adverse events related to pregnancy followed by EPTB and PTB. Levels of FSH, LH, Testosterone and Prolactin in the three sub-groups of TB patients did not show any significant difference (p = 0.683, 0.817, 0.781, and 0.187). Since the total number of infertile patients in our study was only 3, relationship of menstrual abnormalities or serum hormone levels as a predictor of infertility could not be assessed. CONCLUSION: Females suffering from TB experience significantly higher adverse events related to pregnancy than healthy controls. Menstrual abnormalities, infertility and adverse events related to pregnancy were more pronounced in females suffering from GTB than PTB/EPTB. Female patients suffering from any form of TB need to be comprehensively managed. Because of highly sensitive issues related to infertility and reproductive health in today's era, it is imperative that any future complications of the same are kept into consideration in female patients with TB.


Assuntos
Infertilidade/epidemiologia , Distúrbios Menstruais/epidemiologia , Tuberculose dos Genitais Femininos/epidemiologia , Tuberculose Pulmonar/epidemiologia , Adulto , Anemia/sangue , Anemia/epidemiologia , Estudos de Casos e Controles , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Índia/epidemiologia , Hormônio Luteinizante/sangue , Prolactina/sangue , Testosterona/sangue , Tuberculose/sangue , Tuberculose/epidemiologia , Tuberculose dos Genitais Femininos/sangue , Tuberculose Pulmonar/sangue , Adulto Jovem
20.
J Family Med Prim Care ; 9(1): 282-286, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32110605

RESUMO

BACKGROUND: Choosing latest technology for the treatment improves the chances of favorable prognosis and saves the time of the clinician; hence, the aim of the study was to explore their knowledge, attitude, and practice (KAP) toward following proper standards of endodontic practice and use of latest technology. MATERIALS AND METHODS: The present study was a cross-sectional, descriptive questionnaire study conducted among general dental practitioners (GDPs). The survey was conducted among 156 GDPs. In the present study, a close-ended interview schedule was prepared to test the KAP of GDPs. RESULTS: For diagnosis, most of the study participants (58 [37.08%]) relied on case history and radiograph. Apex locator was used by 71 (45.51%) of the study subjects. Among all the study participants, 58 (37.17%) dental practitioners used rotary nickel-titanium (NiTi) files with normal saline and preheated disinfectants for cleaning and shaping of root canal. It was observed that the knowledge of majority of the dental practitioners was fair (58 [37.17%]). However, the attitude and practice toward following proper standards of endodontic practice and use of latest technology were poor. CONCLUSION: It was concluded that very few general practitioners used the latest technology in endodontics. Knowledge was fair while attitude and practice regarding following proper standards of endodontic practice and use of latest technology were poor among study participants.

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