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1.
Int J Comput Assist Radiol Surg ; 19(6): 1103-1111, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38573566

RESUMO

PURPOSE: Cancer confirmation in the operating room (OR) is crucial to improve local control in cancer therapies. Histopathological analysis remains the gold standard, but there is a lack of real-time in situ cancer confirmation to support margin confirmation or remnant tissue. Raman spectroscopy (RS), as a label-free optical technique, has proven its power in cancer detection and, when integrated into a robotic assistance system, can positively impact the efficiency of procedures and the quality of life of patients, avoiding potential recurrence. METHODS: A workflow is proposed where a 6-DOF robotic system (optical camera + MECA500 robotic arm) assists the characterization of fresh tissue samples using RS. Three calibration methods are compared for the robot, and the temporal efficiency is compared with standard hand-held analysis. For healthy/cancerous tissue discrimination, a 1D-convolutional neural network is proposed and tested on three ex vivo datasets (brain, breast, and prostate) containing processed RS and histopathology ground truth. RESULTS: The robot achieves a minimum error of 0.20 mm (0.12) on a set of 30 test landmarks and demonstrates significant time reduction in 4 of the 5 proposed tasks. The proposed classification model can identify brain, breast, and prostate cancer with an accuracy of 0.83 (0.02), 0.93 (0.01), and 0.71 (0.01), respectively. CONCLUSION: Automated RS analysis with deep learning demonstrates promising classification performance compared to commonly used support vector machines. Robotic assistance in tissue characterization can contribute to highly accurate, rapid, and robust biopsy analysis in the OR. These two elements are an important step toward real-time cancer confirmation using RS and OR integration.


Assuntos
Neoplasias da Mama , Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Análise Espectral Raman , Humanos , Análise Espectral Raman/métodos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/diagnóstico , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias da Mama/patologia , Masculino , Feminino , Salas Cirúrgicas , Biópsia/métodos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/diagnóstico
2.
Artigo em Inglês | MEDLINE | ID: mdl-38629867

RESUMO

BACKGROUND: Managing postoperative pain while minimizing opioid-related adverse drug events (ORADEs) remains a significant challenge. The OPI•AID Zone Tool is proposed as a novel clinical decision support tool that - both graphically and in a scoring-system - represents the relationship between pain management and the occurrence of ORADEs, aiming to enhance patient outcomes in postoperative care. The OPI•AID Zone Tool places pain score on the x-axis and an ORADE score on the y-axis, and stratifies patients into five zones to reflect the composite impact of pain severity and ORADEs on the quality of postoperative patient care. The study will have two key aims: (1) to explore whether the OPI•AID Zone Tool can function as a composite outcome measure for postoperative pain and ORADEs, and (2) to evaluate the use of the OPI•AID Zone Tool in visual presentations and for evaluation of patients' postoperative pain management quality. METHODS: This prospective observational cohort study will include 200 adults undergoing various surgical procedures in general anesthesia with a subsequent stay in the post-anesthesia care unit (PACU) at Bispebjerg Hospital, Denmark. Substudy 1 primary outcome: To assess whether a zone score in the OPI•AID Zone Tool is associated with patient-perceived health (EQ VAS), quality of recovery (QoR-PACU), and time to discharge readiness in PACU, and if the zone score has a stronger association than pain and ORADE score in themselves. Substudy 2 primary outcome: To assess how the use of intraoperative non-opioid analgesics impact where patients are placed in the OPI•AID Zone Tool's XY scatterplot right after surgery. To assess if patients who receive more comprehensive non-opioid analgesic basic regimens, generally fall into lower zones. CONCLUSION: The OPI•AID Zone Tool could potentially be a valuable clinical decision-making tool for optimizing postoperative care by simultaneously addressing pain management and the risk of ORADEs. By computing a composite measure of these two critical outcomes, the tool could guide more nuanced and patient-centered analgesic regimens, potentially improving patient satisfaction and operational efficiency in postoperative settings. The tool's applicability will be explored in this observational pilot and followed up in a planned series of studies (opiaid.dk).

3.
Methods Mol Biol ; 2806: 187-196, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38676803

RESUMO

Patient-derived xenograft (PDX) models play a crucial role for in vivo research. They maintain the original molecular characteristics of the human tumor and provide a more accurate tumor microenvironment, which cannot be replicated by in vitro models. This chapter describes four different transplantation methods, namely, intra-bursal, intrarenal capsule, intraperitoneal, and subcutaneous, to develop PDX models for ovarian cancer research.


Assuntos
Modelos Animais de Doenças , Neoplasias Ovarianas , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Neoplasias Ovarianas/patologia , Feminino , Animais , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Microambiente Tumoral , Xenoenxertos
4.
Phys Med Biol ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359453

RESUMO

Cone-beam Computed Tomography (CBCT) is widely used in dental imaging, small animal imaging, radiotherapy, and non-destructive industrial inspection. The quality of CBCT images depends on the precise knowledge of the CBCT system's alignment. We introduce a distinct procedure, "precision alignment loop (PAL)", to calibrate any CBCT system with a circular trajectory. We describe the calibration procedure by using a line-beads phantom, and how PAL determines the misalignments from a CBCT system. PAL also yields the uncertainties in the simulated calibration to give an estimate of the errors in the misalignments. From the analytical simulations, PAL can precisely obtain the source-to-rotation axis distance (SRD), and the geometric center G, "the point in z-axis meets the detector", where the z-axis is coincident with the line from the X-ray source that intersects the axis of the rotation (AOR) orthogonally. The uncertainties of three misalignment angles of the detector are within ±0.05°, which is close to ±0.04° for the results of Yang et al. [18], but our method is easy and simple to implement. Our distinct procedure, on the other hand, yields the calibration of a micro-CT system and an example of reconstructed images, showing our calibration method for the CBCT system to be simple, precise, and accurate.

5.
Fundam Clin Pharmacol ; 38(3): 561-574, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38247119

RESUMO

BACKGROUND: Ageing, sex and polypharmacy affect physical function. OBJECTIVES: This mouse study investigates how ageing, sex and polypharmacy interact and affect grip strength, balance beam and wire hang, correlating and comparing the different test results between and within subgroups. METHODS: Young (2.5 months) and old (21.5 months) C57BL/6 J male and female mice (n = 10-6/group) were assessed for physical function at baseline on grip strength, balance beam and wire hang with three trials of 60 s (WH60s) and one trial of 300 s (WH300s). Mice were randomised to control or diet containing a high Drug Burden Index (DBI, total anticholinergic and sedative drug exposure) polypharmacy regimen (metoprolol, simvastatin, citalopram, oxycodone and oxybutynin at therapeutic oral doses). Following 6-8 weeks of treatment, mice were reassessed. RESULTS: High DBI polypharmacy and control mice both showed age group differences on all tests (p < 0.05). Only control mice showed sex differences, with females outperforming males on the WH60s and balance beam for old mice, WH300s for young mice (p < 0.05). Polypharmacy reduced grip strength in all subgroups (p < 0.05) and only in old females reduced wire hang time and cumulative behaviour and balance beam time and %walked (p < 0.05). Physical function assessments were all correlated with each other, with differences between subgroups (p < 0.05), and mice within subgroups showed interindividual variability in performance. CONCLUSION: Age, sex and polypharmacy have variable effects on different tests, and behavioural measures are useful adjuvants to assessing performance. There was considerable within-group variability in change in measures over time. These findings can inform design and sample size of future studies.


Assuntos
Envelhecimento , Camundongos Endogâmicos C57BL , Polimedicação , Animais , Feminino , Masculino , Envelhecimento/efeitos dos fármacos , Envelhecimento/fisiologia , Camundongos , Fatores Sexuais , Força da Mão , Equilíbrio Postural/efeitos dos fármacos , Caracteres Sexuais
6.
Biochim Biophys Acta Proteins Proteom ; 1872(1): 140971, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37935252

RESUMO

Glutaredoxin 3 (Grx3), a redox protein with a thioredoxin-fold structure, maintains structural integrity and glutathione (GSH) binding capabilities across varying habitat temperatures. The cis-Pro loop, essential for GSH binding, relies on the Arg-Asp salt bridge (α2-α3) and Gln-His hydrogen bond (ß3-ß4) for its conformation. In some psychrophilic Grx3 variants, Arg in α2 is replaced with Tyr, and His in ß4 is replaced with Phe. This study examines the roles of these bonds in Grx3's structure, function, and cold adaptation, using SpGrx3 from the Arctic bacterium Sphingomonas sp. Despite its cold habitat, SpGrx3 maintains the Arg51-Asp69 salt bridge and Gln56-His63 hydrogen bond. The R51Y substitution disrupts the α2-α3 salt bridge, while the H63F and H63Y substitutions hinder the salt bridge through cation-π interactions with Arg51, involving Phe63/Tyr63, thereby enhancing flexibility. Conversely, mutations that disrupt the hydrogen bond (Q56A, H63A, and H63F) reduce thermal stability. In the psychrophilic Grx3 configuration A48T/R51Y/H63F, a Thr48-Gln56 hydrogen bond stabilizes the cis-Pro loop, enhancing flexibility by disrupting both bonds. Furthermore, all mutants exhibit reduced α-helical content and catalytic efficiency. In summary, the highly conserved Arg51-Asp69 salt bridge and Gln56-His63 hydrogen bond are crucial for stabilizing the cis-Pro loop and catalytic activity in SpGrx3. His63 is favored as it avoids cation-π interactions with Arg51, unlike Phe63/Tyr63. Psychrophilic Grx3 variants have adapted to cold environments by reducing GSH binding and increasing structural flexibility. These findings deepen our understanding of the structural conservation in Grx3 for GSH binding and the critical alterations required for cold adaptation.


Assuntos
Glutarredoxinas , Sphingomonas , Glutarredoxinas/genética , Glutarredoxinas/metabolismo , Sphingomonas/genética , Sequência de Aminoácidos , Glutationa/metabolismo , Cátions
7.
PLoS Negl Trop Dis ; 17(11): e0011311, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37934746

RESUMO

BACKGROUND: Under the pressure of Human Adenovirus (HAdV)-associated acute respiratory infection (ARI) outbreak in children in Northern Vietnam in the end of 2022, this study was initiated to identify the HAdV subtype(s) and examine the associated clinical features and risk factors of more severe cases. METHODS: This study evaluated pediatric patients with ARI which had tested positive for HAdV between October and November 2022 using a multiplex real-time PCR panel. Nasopharyngeal aspirates or nasal swab samples were used for sequencing to identify HAdV subtypes. Clinical data were collected retrospectively. RESULTS: Among 97 successfully sequenced samples, the predominant subtypes were HAdV-B3 (83%), HAdV-B7 (16%) and HAdV-C2 (1%). Lower respiratory manifestations were found in 25% of the patients of which 5% were diagnosed with severe pneumonia. There was no significant association between HAdV subtype and clinical features except higher white blood cell and neutrophil counts in those detected with HAdV-B3 (p<0.001). Co-detection of HAdV with ≥1 other respiratory viruses was found in 13/24(54%) of those with lower respiratory manifestations and 4/5(80%) of those with severe pneumonia (odds ratio (95% confidence interval) vs. those without = 10.74 (2.83, 48.17) and 19.44 (2.12, 492.73) respectively after adjusting for age, sex, birth delivery method, day of disease). CONCLUSION: HAdV-B3 and HAdV-B7 were predominant in the outbreak. Co-detection of HAdV together with other respiratory viruses was a strong risk factor for lower respiratory tract illnesses and severe pneumonia. The findings advocate the advantages of multi-factor microbial panels for the diagnosis and prognosis of ARI in children.


Assuntos
Infecções por Adenoviridae , Infecções por Adenovirus Humanos , Adenovírus Humanos , Pneumonia , Infecções Respiratórias , Humanos , Criança , Lactente , Adenoviridae , Vietnã/epidemiologia , Estudos Retrospectivos , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/diagnóstico , Infecções Respiratórias/epidemiologia , Pneumonia/epidemiologia , Adenovírus Humanos/genética , Infecções por Adenoviridae/epidemiologia , Surtos de Doenças , Fatores de Risco , Filogenia
8.
J Biomed Opt ; 28(9): 090501, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37692565

RESUMO

Significance: Lung cancer is the most frequently diagnosed cancer overall and the deadliest cancer in North America. Early diagnosis through current bronchoscopy techniques is limited by poor diagnostic yield and low specificity, especially for lesions located in peripheral pulmonary locations. Even with the emergence of robotic-assisted platforms, bronchoscopy diagnostic yields remain below 80%. Aim: The aim of this study was to determine whether in situ single-point fingerprint (800 to 1700 cm-1) Raman spectroscopy coupled with machine learning could detect lung cancer within an otherwise heterogenous background composed of normal tissue and tissue associated with benign conditions, including emphysema and bronchiolitis. Approach: A Raman spectroscopy probe was used to measure the spectral fingerprint of normal, benign, and cancer lung tissue in 10 patients. Each interrogated specimen was characterized by histology to determine cancer type, i.e., small cell carcinoma or non-small cell carcinoma (adenocarcinoma and squamous cell carcinoma). Biomolecular information was extracted from the fingerprint spectra to identify biomolecular features that can be used for cancer detection. Results: Supervised machine learning models were trained using leave-one-patient-out cross-validation, showing lung cancer could be detected with a sensitivity of 94% and a specificity of 80%. Conclusions: This proof of concept demonstrates fingerprint Raman spectroscopy is a promising tool for the detection of lung cancer during diagnostic procedures and can capture biomolecular changes associated with the presence of cancer among a complex heterogeneous background within less than 1 s.


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Análise Espectral Raman , Neoplasias Pulmonares/diagnóstico por imagem , Pulmão/diagnóstico por imagem
9.
J Biomed Opt ; 28(5): 057003, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37265877

RESUMO

Significance: Orthopedic surgery is frequently performed but currently lacks consensus and availability of ideal guidance methods, resulting in high variability of outcomes. Misdirected insertion of surgical instruments can lead to weak anchorage and unreliable fixation along with risk to critical structures including the spinal cord. Current methods for surgical guidance using conventional medical imaging are indirect and time-consuming with unclear advantages. Aim: The purpose of this study was to investigate the potential of intraoperative in situ near-infrared Raman spectroscopy (RS) combined with machine learning in guiding pedicular screw insertion in the spine. Approach: A portable system equipped with a hand-held RS probe was used to make fingerprint measurements on freshly excised porcine vertebrae, identifying six tissue types: bone, spinal cord, fat, cartilage, ligament, and muscle. Supervised machine learning techniques were used to train-and test on independent hold-out data subsets-a six-class model as well as two-class models engineered to distinguish bone from soft tissue. The two-class models were further tested using in vivo spectral fingerprint measurements made during intra-pedicular drilling in a porcine spine model. Results: The five-class model achieved >96% accuracy in distinguish all six tissue classes when applied onto a hold-out testing data subset. The binary classifier detecting bone versus soft tissue (all soft tissue or spinal cord only) yielded 100% accuracy. When applied onto in vivo measurements performed during interpedicular drilling, the soft tissue detection models correctly detected all spinal canal breaches. Conclusions: We provide a foundation for RS in the orthopedic surgical guidance field. It shows that RS combined with machine learning is a rapid and accurate modality capable of discriminating tissues that are typically encountered in orthopedic procedures, including pedicle screw placement. Future development of integrated RS probes and surgical instruments promises better guidance options for the orthopedic surgeon and better patient outcomes.


Assuntos
Procedimentos Ortopédicos , Parafusos Pediculares , Ftirápteros , Cirurgia Assistida por Computador , Suínos , Animais , Análise Espectral Raman , Cirurgia Assistida por Computador/métodos , Procedimentos Ortopédicos/métodos
10.
J Biomed Opt ; 28(3): 036009, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37009577

RESUMO

Significance: As many as 60% of patients with early stage breast cancer undergo breast-conserving surgery. Of those, 20% to 35% need a second surgery because of incomplete resection of the lesions. A technology allowing in situ detection of cancer could reduce re-excision procedure rates and improve patient survival. Aim: Raman spectroscopy was used to measure the spectral fingerprint of normal breast and cancer tissue ex-vivo. The aim was to build a machine learning model and to identify the biomolecular bands that allow one to detect invasive breast cancer. Approach: The system was used to interrogate specimens from 20 patients undergoing lumpectomy, mastectomy, or breast reduction surgery. This resulted in 238 ex-vivo measurements spatially registered with standard histology classifying tissue as cancer, normal, or fat. A technique based on support vector machines led to the development of predictive models, and their performance was quantified using a receiver-operating-characteristic analysis. Results: Raman spectroscopy combined with machine learning detected normal breast from ductal or lobular invasive cancer with a sensitivity of 93% and a specificity of 95%. This was achieved using a model based on only two spectral bands, including the peaks associated with C-C stretching of proteins around 940 cm - 1 and the symmetric ring breathing at 1004 cm - 1 associated with phenylalanine. Conclusions: Detection of cancer on the margins of surgically resected breast specimen is feasible with Raman spectroscopy.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Análise Espectral Raman/métodos , Mastectomia , Mastectomia Segmentar/métodos , Proteínas , Carcinoma Ductal de Mama/cirurgia
11.
J Gerontol A Biol Sci Med Sci ; 78(2): 213-222, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36124741

RESUMO

Aging, medication use, and global function are associated with changes in the microbiome. However, their interrelationships and changes over time require further characterization. In a longitudinal aging mouse study, we investigated the effects of aging, chronic polypharmacy with a high Drug Burden Index (DBI, measure of total anticholinergic and sedative medication exposure) and gradual cessation (deprescribing) on the microbiome, further exploring any association with global outcomes. Chronic administration of high DBI polypharmacy attenuated the aging-related reduction in alpha diversity, which was not sustained after deprescribing. Beta diversity and LEfSe (Linear discriminant analysis Effect Size) features varied with age, polypharmacy, and deprescribing. Aging with and without polypharmacy shared decreases in Bifidobacteriaceae, Paraprevotellaceae, Bacteroidaceae, and Clostridiaceae, while only aging with polypharmacy showed increased LEfSe features. Microbiome diversity correlated with frailty, nesting, and open field performance. Polypharmacy deprescribing reversed changes that occurred with treatment. However, the microbiome did not recover to its pretreatment composition at 12 months, nor develop the same aging-related changes from 12 to 24 months as the control group. Overall, aging, chronic polypharmacy, and deprescribing differentially affected the diversity and composition of the gut microbiome, which is associated with frailty and function.


Assuntos
Desprescrições , Fragilidade , Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Polimedicação , Envelhecimento
12.
Sci Rep ; 12(1): 2168, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35140291

RESUMO

Aging, polypharmacy (concurrent use of ≥ 5 medications), and functional impairment are global healthcare challenges. However, knowledge of the age/sex-specific effects of polypharmacy is limited, particularly on daily physical activities. Using continuous monitoring, we demonstrated how polypharmacy with high Drug Burden Index (DBI-cumulative anticholinergic/sedative exposure) affected behaviors over 23 h in male/female, young/old mice. For comparison, we also evaluated how different drug regimens (polypharmacy/monotherapy) influenced activities in young mice. We found that after 4 weeks of treatment, high DBI (HDBI) polypharmacy decreased exploration (reduced mean gait speed and climbing) during the habituation period, but increased it during other periods, particularly in old mice during the transition to inactivity. After HDBI polypharmacy, mean gait speed consistently decreased throughout the experiment. Some behavioral declines after HDBI were more marked in females than males, indicating treatment × sex interactions. Metoprolol and simvastatin monotherapies increased activities in young mice, compared to control/polypharmacy. These findings highlight that in mice, some polypharmacy-associated behavioral changes are greater in old age and females. The observed diurnal behavioral changes are analogous to drug-induced delirium and sundowning seen in older adults. Future mechanistic investigations are needed to further inform considerations of age, sex, and polypharmacy to optimize quality use of medicines.


Assuntos
Envelhecimento , Comportamento Animal , Ritmo Circadiano , Locomoção , Polimedicação , Fatores Etários , Animais , Antagonistas Colinérgicos/administração & dosagem , Comportamento Exploratório , Feminino , Hipnóticos e Sedativos/administração & dosagem , Masculino , Metoprolol/administração & dosagem , Camundongos , Fatores Sexuais , Sinvastatina/administração & dosagem
13.
J Gerontol A Biol Sci Med Sci ; 76(10): 1748-1756, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-33780539

RESUMO

Males and females may respond differently to medications, yet knowledge about sexual dimorphisms in the effects of polypharmacy remains limited, particularly in aging. This study aimed to assess the effect of high Drug Burden Index (DBI) polypharmacy treatment compared to control on physical function and behavior in young and old, male and female mice. We studied whether age and sex play a role in physical function and behavior following polypharmacy treatment and whether they are paralleled by differences in serum drug levels. Young (2.5 months) and old (21.5 months), C57BL/6 mice were randomized to control or high DBI polypharmacy treatment (simvastatin, metoprolol, oxybutynin, oxycodone, and citalopram; n = 6-8/group) for 4-6 weeks. Compared to control, polypharmacy reduced physical function (grip strength, rotarod latency, gait speed, and total distance), middle zone distance (increased anxiety), and nesting score (reduced activities of daily living) in mice of both ages and sexes (p < .001). Old animals had a greater decline in nesting score (p < .05) and midzone distance (p < .001) than young animals. Grip strength declined more in males than females (p < .05). Drug levels at steady state were not significantly different between polypharmacy-treated animals of both ages and sexes. We observed polypharmacy-induced functional impairment in both age and sex groups, with age and sex interactions in the degree of impairment, which were not explained by serum drug levels. Studies of the pathogenesis of functional impairment from polypharmacy may improve management strategies in both sexes.


Assuntos
Preparações Farmacêuticas , Polimedicação , Atividades Cotidianas , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Velocidade de Caminhada
14.
Viruses ; 12(11)2020 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-33171603

RESUMO

Multidrug resistance continues to be a barrier to the effectiveness of highly active antiretroviral therapy in the treatment of human immunodeficiency virus 1 (HIV-1) infection. Darunavir (DRV) is a highly potent protease inhibitor (PI) that is oftentimes effective when drug resistance has emerged against first-generation inhibitors. Resistance to darunavir does evolve and requires 10-20 amino acid substitutions. The conformational landscapes of six highly characterized HIV-1 protease (PR) constructs that harbor up to 19 DRV-associated mutations were characterized by distance measurements with pulsed electron double resonance (PELDOR) paramagnetic resonance spectroscopy, namely double electron-electron resonance (DEER). The results show that the accumulated substitutions alter the conformational landscape compared to PI-naïve protease where the semi-open conformation is destabilized as the dominant population with open-like states becoming prevalent in many cases. A linear correlation is found between values of the DRV inhibition parameter Ki and the open-like to closed-state population ratio determined from DEER. The nearly 50% decrease in occupancy of the semi-open conformation is associated with reduced enzymatic activity, characterized previously in the literature.


Assuntos
Darunavir/farmacologia , Farmacorresistência Viral Múltipla , Inibidores da Protease de HIV/farmacologia , Protease de HIV/química , HIV/efeitos dos fármacos , Substituição de Aminoácidos , Variação Genética , HIV/genética , Protease de HIV/genética , Mutação , Conformação Proteica
15.
Bioorg Med Chem ; 28(22): 115740, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-33007553

RESUMO

Coenzyme A (CoA) is a highly selective inhibitor of the mitotic regulatory enzyme Aurora A kinase, with a novel mode of action. Herein we report the design and synthesis of analogues of CoA as inhibitors of Aurora A kinase. We have designed and synthesised modified CoA structures as potential inhibitors, combining dicarbonyl mimics of the pyrophosphate group with a conserved adenosine headgroup and different length pantetheine-based tail groups. An analogue with a -SH group at the end of the pantotheinate tail showed the best IC50, probably due to the formation of a covalent bond with Aurora A kinase Cys290.


Assuntos
Aurora Quinase A/antagonistas & inibidores , Coenzima A/farmacologia , Difosfatos/farmacologia , Desenho de Fármacos , Panteteína/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Aurora Quinase A/metabolismo , Coenzima A/síntese química , Coenzima A/química , Difosfatos/química , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Panteteína/química , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade
16.
Nat Protoc ; 15(9): 2920-2955, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32788719

RESUMO

Characterization of immune responses is currently hampered by the lack of systems enabling quantitative and dynamic phenotypic characterization of individual cells and, in particular, analysis of secreted proteins such as cytokines and antibodies. We recently developed a simple and robust microfluidic platform, DropMap, to measure simultaneously the kinetics of secretion and other cellular characteristics, including endocytosis activity, viability and expression of cell-surface markers, from tens of thousands of single immune cells. Single cells are compartmentalized in 50-pL droplets and analyzed using fluorescence microscopy combined with an immunoassay based on fluorescence relocation to paramagnetic nanoparticles aligned to form beadlines in a magnetic field. The protocol typically takes 8-10 h after preparation of microfluidic chips and chambers, which can be done in advance. By contrast, enzyme-linked immunospot (ELISPOT), flow cytometry, time-of-flight mass cytometry (CyTOF), and single-cell sequencing enable only end-point measurements and do not enable direct, quantitative measurement of secreted proteins. We illustrate how this system can be used to profile downregulation of tumor necrosis factor-α (TNF-α) secretion by single monocytes in septic shock patients, to study immune responses by measuring rates of cytokine secretion from single T cells, and to measure affinity of antibodies secreted by single B cells.


Assuntos
Sistema Imunitário/citologia , Dispositivos Lab-On-A-Chip , Fenótipo , Análise de Célula Única/instrumentação , Animais , Linfócitos B/citologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Camundongos , Microscopia de Fluorescência
17.
BMC Bioinformatics ; 21(1): 244, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539680

RESUMO

BACKGROUND: The misregulation of microRNA (miRNA) has been shown to cause diseases. Recently, we have proposed a computational method based on a random walk framework on a miRNA-target gene network to predict disease-associated miRNAs. The prediction performance of our method is better than that of some existing state-of-the-art network- and machine learning-based methods since it exploits the mutual regulation between miRNAs and their target genes in the miRNA-target gene interaction networks. RESULTS: To facilitate the use of this method, we have developed a Cytoscape app, named RWRMTN, to predict disease-associated miRNAs. RWRMTN can work on any miRNA-target gene network. Highly ranked miRNAs are supported with evidence from the literature. They then can also be visualized based on the rankings and in relationships with the query disease and their target genes. In addition, automation functions are also integrated, which allow RWRMTN to be used in workflows from external environments. We demonstrate the ability of RWRMTN in predicting breast and lung cancer-associated miRNAs via workflows in Cytoscape and other environments. CONCLUSIONS: Considering a few computational methods have been developed as software tools for convenient uses, RWRMTN is among the first GUI-based tools for the prediction of disease-associated miRNAs which can be used in workflows in different environments.


Assuntos
Biologia Computacional/métodos , Redes Reguladoras de Genes/genética , MicroRNAs/genética , Humanos
18.
Chem Sci ; 11(46): 12522-12532, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34094453

RESUMO

Metabolic glycan engineering (MGE) coupled with nitroxide spin-labeling (SL) was utilized to investigate the heterogeneous environment of cell surface glycans in select cancer and normal cells. This approach exploited the incorporation of azides into cell surface glycans followed by a click reaction with a new nitroxide spin label. Both sialic acid and N-acetylglucosamine (GlcNAc) were targeted for spin labelling. Although each of these moieties experiences a diverse and heterogeneous glycan environment, their EPR spectra and hence mobility are both characterized as a linear combination of two distinct spectra where one component reflects a highly mobile or uncrowded micro-environment with the second component reflecting more restricted motion, reflective of increased crowding and packing within the glycocalyx. What differs among the spectra of the targeted glycans is the relative percentage of each component, with sialic acid moieties experiencing on average an ∼80% less crowded environment, where conversely GlcNAc/GalNAz labeled sites reported on average a ∼50% more crowded environment. These distinct environments are consistent with the organization of sugar moieties within cellular glycans where some residues occur close to the cell membrane/protein backbone (i.e. more restricted) and others are more terminal in the glycan (i.e. more mobile). Strikingly, different cell lines displayed varied relative populations of these two components, suggesting distinctive glycan packing, organization, and composition of different cells. This work demonstrates the capability of SDSL EPR to be a broadly useful tool for studying glycans on cells, and interpretation of the results provides insights for distinguishing the differences and changes in the local organization and heterogeneity of the cellular glycocalyx.

19.
Redox Biol ; 28: 101318, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31546169

RESUMO

Aurora A kinase is a master mitotic regulator whose functions are controlled by several regulatory interactions and post-translational modifications. It is frequently dysregulated in cancer, making Aurora A inhibition a very attractive antitumor target. However, recently uncovered links between Aurora A, cellular metabolism and redox regulation are not well understood. In this study, we report a novel mechanism of Aurora A regulation in the cellular response to oxidative stress through CoAlation. A combination of biochemical, biophysical, crystallographic and cell biology approaches revealed a new and, to our knowledge, unique mode of Aurora A inhibition by CoA, involving selective binding of the ADP moiety of CoA to the ATP binding pocket and covalent modification of Cys290 in the activation loop by the thiol group of the pantetheine tail. We provide evidence that covalent CoA modification (CoAlation) of Aurora A is specific, and that it can be induced by oxidative stress in human cells. Oxidising agents, such as diamide, hydrogen peroxide and menadione were found to induce Thr 288 phosphorylation and DTT-dependent dimerization of Aurora A. Moreover, microinjection of CoA into fertilized mouse embryos disrupts bipolar spindle formation and the alignment of chromosomes, consistent with Aurora A inhibition. Altogether, our data reveal CoA as a new, rather selective, inhibitor of Aurora A, which locks this kinase in an inactive state via a "dual anchor" mechanism of inhibition that might also operate in cellular response to oxidative stress. Finally and most importantly, we believe that these novel findings provide a new rationale for developing effective and irreversible inhibitors of Aurora A, and perhaps other protein kinases containing appropriately conserved Cys residues.


Assuntos
Aurora Quinase A/química , Aurora Quinase A/metabolismo , Coenzima A/administração & dosagem , Animais , Coenzima A/química , Coenzima A/farmacologia , Cristalografia por Raios X , Células HEK293 , Células Hep G2 , Humanos , Camundongos , Modelos Moleculares , Estresse Oxidativo , Fosforilação , Conformação Proteica , Fuso Acromático/efeitos dos fármacos , Fuso Acromático/metabolismo
20.
BMC Infect Dis ; 19(1): 951, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703561

RESUMO

BACKGROUND: In Vietnam, a country with a high tuberculosis (TB) burden, health professionals in both TB-specialized and non-TB-specialized general hospitals have a high risk of acquiring TB. The aims of the present study were to clarify the difficulties in TB infection control at non-TB specialized hospitals and whether any associated risks of latent TB infection exist among health professionals in Vietnam. METHODS: We conducted a cross-sectional study in a national tertiary and general hospital of Hanoi, Vietnam. Participants were health professionals, including physicians, nurses, and other health professionals. We assessed difficulties in TB infection control by conducting a knowledge, attitude, and practice (KAP) survey. We also collected data on the results of tuberculin skin tests (TSTs) conducted during health check-ups for hospital staff to determine whether health professionals had latent TB infection or TB disease. KAP scores were compared among health professional groups (physicians vs. nurses vs. other health professionals). Factors influencing knowledge scores were evaluated using multiple regression analysis. RESULTS: A total 440 health professionals at the study site participated in the KAP survey, and we collected the results of TSTs from a total of 299 health professionals. We observed a high prevalence of latent TB infection (74.2%), especially among participants in the emergency department. Although participants had high KAP scores, some topics were less understood, such as symptoms and risks of TB, proper use of protective equipment such as N95 respirators, and preventing transmission by patients with confirmed or suspected TB. Factors influencing knowledge scores associated with TB were age, a belief that TB is the most important infectious disease, being a medical professional, having previously attended workshops or seminars, and knowing that Vietnam has a high burden of TB. CONCLUSION: In a non-TB specialized hospital of Vietnam, we observed a risk of TB infection among health professionals and difficulties in properly controlling TB infection. Early awareness regarding patients with suspected TB, to apply proper measures and prevent transmission, and education regarding obtaining updated knowledge through scientific information are crucial to enhancing TB infection control in general hospitals of Vietnam.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Hospitais Gerais , Controle de Infecções , Tuberculose Latente/diagnóstico , Tuberculose Latente/epidemiologia , Programas de Rastreamento , Inquéritos e Questionários , Adulto , Estudos Transversais , Feminino , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Tuberculose Latente/prevenção & controle , Masculino , Mycobacterium tuberculosis/imunologia , Prevalência , Dispositivos de Proteção Respiratória , Teste Tuberculínico , Vietnã
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