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1.
J Med Virol ; 96(3): e29506, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38445718

RESUMO

With the global pandemic and the continuous mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the need for effective and broadly neutralizing treatments has become increasingly urgent. This study introduces a novel strategy that targets two aspects simultaneously, using bifunctional antibodies to inhibit both the attachment of SARS-CoV-2 to host cell membranes and viral fusion. We developed pioneering IgG4-(HR2)4 bifunctional antibodies by creating immunoglobulin G4-based and phage display-derived human monoclonal antibodies (mAbs) that specifically bind to the SARS-CoV-2 receptor-binding domain, engineered with four heptad repeat 2 (HR2) peptides. Our in vitro experiments demonstrate the superior neutralization efficacy of these engineered antibodies against various SARS-CoV-2 variants, ranging from original SARS-CoV-2 strain to the recently emerged Omicron variants, as well as SARS-CoV, outperforming the parental mAb. Notably, intravenous monotherapy with the bifunctional antibody neutralizes a SARS-CoV-2 variant in a murine model without causing significant toxicity. In summary, this study unveils the significant potential of HR2 peptide-driven bifunctional antibodies as a potent and versatile strategy for mitigating SARS-CoV-2 infections. This approach offers a promising avenue for rapid development and management in the face of the continuously evolving SARS-CoV-2 variants, holding substantial promise for pandemic control.


Assuntos
Anticorpos Biespecíficos , COVID-19 , Humanos , Animais , Camundongos , SARS-CoV-2/genética , Anticorpos Monoclonais/uso terapêutico , Imunoglobulina G , Peptídeos/genética , Poder Psicológico
2.
Environ Toxicol ; 39(6): 3500-3511, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38456238

RESUMO

Urban Particulate Matter (UPM) induces skin aging and inflammatory responses by regulating skin cells through the transient receptor potential vanilloid 1 (TRPV1). Although oleic acid, an unsaturated free fatty acid (FFA), has some functional activities, its effect on UPM-induced skin damage has not been elucidated. Here, we investigated signaling pathways on how oleic acid is involved in attenuating UPM induced cell damage. UPM treatment increased XRE-promoter luciferase activity and increased translocation of AhR to the nucleus, resulting in the upregulation of CYP1A1 gene. However, oleic acid treatment attenuated the UPM effects on AhR signaling. Furthermore, while UPM induced activation of TRPV1 and MAPKs signaling which activated the downstream molecules NFκB and AP-1, these effects were reduced by cotreatment with oleic acid. UPM-dependent generation of reactive oxygen species (ROS) and reduction of cellular proliferation were also attenuated by the treatment of oleic acid. These data reveal that cell damage induced by UPM treatment occurs through AhR signaling and TRPV1 activation which in turn activates ERK and JNK, ultimately inducing NFκB and AP-1 activation. These effects were reduced by the cotreatment of oleic acid on HaCaT cells. These suggest that oleic acid reduces UPM-induced cell damage through inhibiting both the AhR signaling and activation of TRPV1 and its downstream molecules, leading to a reduction of pro-inflammatory cytokine and recovery of cell proliferation.


Assuntos
Poluentes Atmosféricos , Ácido Oleico , Material Particulado , Receptores de Hidrocarboneto Arílico , Transdução de Sinais , Canais de Cátion TRPV , Humanos , Poluentes Atmosféricos/toxicidade , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A1/genética , Células HaCaT , NF-kappa B/metabolismo , Ácido Oleico/farmacologia , Ácido Oleico/toxicidade , Material Particulado/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/genética
3.
Int J Mol Sci ; 25(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38732011

RESUMO

Immunoglobulin G-based monoclonal antibodies (mAbs) have been effective in treating various diseases, but their large molecular size can limit their penetration of tissue and efficacy in multifactorial diseases, necessitating the exploration of alternative forms. In this study, we constructed a phage display library comprising single-domain antibodies (sdAbs; or "VHHs"), known for their small size and remarkable stability, using a total of 1.6 × 109 lymphocytes collected from 20 different alpacas, resulting in approximately 7.16 × 1010 colonies. To assess the quality of the constructed library, next-generation sequencing-based high-throughput profiling was performed, analyzing approximately 5.65 × 106 full-length VHH sequences, revealing 92% uniqueness and confirming the library's diverse composition. Systematic characterization of the library revealed multiple sdAbs with high affinity for three therapeutically relevant antigens. In conclusion, our alpaca sdAb phage display library provides a versatile resource for diagnostics and therapeutics. Furthermore, the library's vast natural VHH antibody repertoire offers insights for generating humanized synthetic sdAb libraries, further advancing sdAb-based therapeutics.


Assuntos
Camelídeos Americanos , Biblioteca de Peptídeos , Anticorpos de Domínio Único , Anticorpos de Domínio Único/genética , Anticorpos de Domínio Único/imunologia , Anticorpos de Domínio Único/química , Animais , Camelídeos Americanos/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/genética , Ensaios de Triagem em Larga Escala/métodos , Afinidade de Anticorpos , Técnicas de Visualização da Superfície Celular/métodos
4.
BMC Cancer ; 23(1): 490, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37259024

RESUMO

BACKGROUND: Thrombocytopenia is a common complication in cancer patients undergoing chemotherapy. Chemotherapy-induced thrombocytopenia (CIT) leads to dose reduction and treatment delays, lowering chemotherapy efficacy and survival rate. Thus, rapid recovery and continuous maintenance of platelet count during chemotherapy cycles are crucial in patients with CIT. Thrombopoietin (TPO) and its receptor, myeloid proliferative leukemia (MPL) protein, play a major role in platelet production. Although several MPL agonists have been developed to regulate thrombopoiesis, none have been approved for the management of CIT due to concerns regarding efficacy or safety. Therefore, the development of effective MPL agonists for treating CIT needs to be further expanded. METHODS: Anti-MPL antibodies were selected from the human combinatorial antibody phage libraries using phage display. We identified 2R13 as the most active clone among the binding antibodies via cell proliferation assay using BaF3/MPL cells. The effect of 2R13 on megakaryocyte differentiation was evaluated in peripheral blood CD34+ cells by analyzing megakaryocyte-specific differentiation markers (CD41a+ and CD42b+) and DNA ploidy using flow cytometry. The 2R13-induced platelet production was examined in 8- to 10-week-old wild-type BALB/c female mice and a thrombocytopenia mouse model established by intraperitoneal injection of 5-fluorouracil (150 mg/kg). The platelet counts were monitored twice a week over 14 days post-initiation of treatment with a single injection of 2R13, or recombinant human TPO (rhTPO) for seven consecutive days. RESULTS: We found that 2R13 specifically interacted with MPL and activated its signaling pathways. 2R13 stimulated megakaryocyte differentiation, evidenced by increasing the proportion of high-ploidy (≥ 8N) megakaryocytes in peripheral blood-CD34+ cells. The platelet count was increased by a single injection of 2R13 for up to 14 days. Injection of 5-fluorouracil considerably reduced the platelet count by day 4, which was recovered by 2R13. The platelets produced by 2R13 sustained a higher count than that achieved using seven consecutive injections of rhTPO. CONCLUSIONS: Our findings suggest that 2R13 is a promising therapeutic agent for CIT treatment.


Assuntos
Antineoplásicos , Trombocitopenia , Camundongos , Animais , Humanos , Feminino , Receptores de Trombopoetina , Plaquetas/metabolismo , Trombopoese , Anticorpos , Proteínas Recombinantes/efeitos adversos , Antígenos CD34 , Fluoruracila/uso terapêutico , Trombocitopenia/induzido quimicamente , Trombocitopenia/tratamento farmacológico , Antineoplásicos/efeitos adversos
5.
Int J Mol Sci ; 24(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36983085

RESUMO

Antibody phage display is a key technology for the discovery and development of target-specific monoclonal antibodies (mAbs) for use in research, diagnostics, and therapy. The construction of a high-quality antibody library, with larger and more diverse antibody repertoires, is essential for the successful development of phage display-derived mAbs. In this study, a large human combinatorial single-chain variable fragment library (1.5 × 1011 colonies) was constructed from Epstein-Barr virus-infected human peripheral blood mononuclear cells stimulated with a combination of two of the activators of human B cells, the Toll-like receptor 7/8 agonist R848 and interleukin-2. Next-generation sequencing analysis with approximately 1.9 × 106 and 2.7 × 106 full-length sequences of heavy chain variable (VH) and κ light chain variable (Vκ) domains, respectively, revealed that the library consists of unique VH (approximately 94%) and Vκ (approximately 91%) sequences with greater diversity than germline sequences. Lastly, multiple unique mAbs with high affinity and broad cross-species reactivity could be isolated from the library against two therapeutically relevant target antigens, validating the library quality. These findings suggest that the novel antibody library we have developed may be useful for the rapid development of target-specific phage display-derived recombinant human mAbs for use in therapeutic and diagnostic applications.


Assuntos
Infecções por Vírus Epstein-Barr , Biblioteca de Peptídeos , Humanos , Leucócitos Mononucleares , Herpesvirus Humano 4 , Anticorpos Monoclonais/genética , Sequenciamento de Nucleotídeos em Larga Escala
6.
Int J Mol Sci ; 23(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35805896

RESUMO

Small-cell lung cancer (SCLC) is the most aggressive form of lung cancer and the leading cause of global cancer-related mortality. Despite the earlier identification of membrane-proximal cleavage of cell adhesion molecule 1 (CADM1) in cancers, the role of the membrane-bound fragment of CAMD1 (MF-CADM1) is yet to be clearly identified. In this study, we first isolated MF-CADM1-specific fully human single-chain variable fragments (scFvs) from the human synthetic scFv antibody library using the phage display technology. Following the selected scFv conversion to human immunoglobulin G1 (IgG1) scFv-Fc antibodies (K103.1-4), multiple characterization studies, including antibody cross-species reactivity, purity, production yield, and binding affinity, were verified. Finally, via intensive in vitro efficacy and toxicity evaluation studies, we identified K103.3 as a lead antibody that potently promotes the death of human SCLC cell lines, including NCI-H69, NCI-H146, and NCI-H187, by activated Jurkat T cells without severe endothelial toxicity. Taken together, these findings suggest that antibody-based targeting of MF-CADM1 may be an effective strategy to potentiate T cell-mediated SCLC death, and MF-CADM1 may be a novel potential therapeutic target in SCLC for antibody therapy.


Assuntos
Neoplasias Pulmonares , Anticorpos de Cadeia Única , Carcinoma de Pequenas Células do Pulmão , Molécula 1 de Adesão Celular/genética , Técnicas de Visualização da Superfície Celular , Humanos , Anticorpos de Cadeia Única/farmacologia
7.
J Med Internet Res ; 23(7): e28361, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-36260382

RESUMO

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is a serious public health issue, and predicting the prognosis of OHCA patients can assist clinicians in making decisions about the treatment of patients, use of hospital resources, or termination of resuscitation. OBJECTIVE: This study aimed to develop a time-adaptive conditional prediction model (TACOM) to predict clinical outcomes every minute. METHODS: We performed a retrospective observational study using data from the Korea OHCA Registry in South Korea. In this study, we excluded patients with trauma, those who experienced return of spontaneous circulation before arriving in the emergency department (ED), and those who did not receive cardiopulmonary resuscitation (CPR) in the ED. We selected patients who received CPR in the ED. To develop the time-adaptive prediction model, we organized the training data set as ongoing CPR patients by the minute. A total of 49,669 patients were divided into 39,602 subjects for training and 10,067 subjects for validation. We compared random forest, LightGBM, and artificial neural networks as the prediction model methods. Model performance was quantified using the prediction probability of the model, area under the receiver operating characteristic curve (AUROC), and area under the precision recall curve. RESULTS: Among the three algorithms, LightGBM showed the best performance. From 0 to 30 min, the AUROC of the TACOM for predicting good neurological outcomes ranged from 0.910 (95% CI 0.910-0.911) to 0.869 (95% CI 0.865-0.871), whereas that for survival to hospital discharge ranged from 0.800 (95% CI 0.797-0.800) to 0.734 (95% CI 0.736-0.740). The prediction probability of the TACOM showed similar flow with cohort data based on a comparison with the conventional model's prediction probability. CONCLUSIONS: The TACOM predicted the clinical outcome of OHCA patients per minute. This model for predicting patient outcomes by the minute can assist clinicians in making rational decisions for OHCA patients.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Estudos de Coortes , Reanimação Cardiopulmonar/métodos , Sistema de Registros , Serviço Hospitalar de Emergência
8.
Int J Psychiatry Med ; 55(2): 105-113, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31488003

RESUMO

Objective: Among the risk factors for cerebrovascular/cardiovascular disease or thromboembolic events caused by the administration of second-generation antipsychotics, clinicians have mainly focused on metabolic side effects, with little interest in the effects on platelet activity. Because excessive platelet activity can increase the risk for cerebrovascular/cardiovascular disease, the aim of this study was to investigate the effect of second-generation antipsychotics on platelet activity in patients with schizophrenia. Methods: The medical records of patients with schizophrenia who were treated with second-generation antipsychotics were retrospectively reviewed. The degree of platelet activation was assessed by measuring the mean platelet component. Results: Wilcoxon signed-rank test revealed that mean platelet component levels were significantly decreased by the administration of second-generation antipsychotics (V = 20; p < 0.05), suggesting that the administration of second-generation antipsychotics may increase platelet activation. Conclusion: Because platelet activation is an additional risk factor for the occurrence of cerebrovascular/cardiovascular disease, results of this study suggest that clinicians should carefully monitor the degree of platelet activation after the administration of second-generation antipsychotics.


Assuntos
Antipsicóticos/farmacologia , Plaquetas/efeitos dos fármacos , Esquizofrenia/tratamento farmacológico , Adolescente , Adulto , Antipsicóticos/uso terapêutico , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
9.
Int J Mol Sci ; 19(9)2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30205521

RESUMO

Urban particulate matter (UPM) exerts negative effects on various human organs. Transient receptor potential vanilloid 1 (TRPV1) is a polymodal sensory transducer that can be activated by multiple noxious stimuli. This study aimed to explore the effects of the UPM 1648a on the expression of TRPV1, and its regulatory mechanisms in HaCaT cells. UPM enhanced TRPV 1 promoter-luciferase reporter activity. UPM also increased expression of the TRPV 1 gene as evidenced by increased mRNA and protein levels of TRPV 1. In addition, elucidation of the underlying mechanism behind the UPM-mediated effects on TRPV 1 expression revealed that UPM can upregulate expression of the TRPV1 gene by activating activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB). The UPM treatment also altered Ca2+ influx and cell proliferation, as well as production of interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α), and interleukin-1ß (IL-1ß). In addition, these UPM-induced effects were attenuated by SB203580 and ammonium pyrrolidinedithiocarbamate (PDTC). However, SP600125 and PD98059 did not alter the UPM-induced effects. Taken together, these findings indicate that UPM upregulates expression of the TRPV 1 gene, which is mediated by the p38 mitogen-activated protein kinase (MAPK) and NF-κB signaling pathways and suggest that UPM is a potential irritant that can induce skin processes such as aging and inflammatory responses.


Assuntos
Queratinócitos/metabolismo , NF-kappa B/metabolismo , Material Particulado/efeitos adversos , Transdução de Sinais , Canais de Cátion TRPV/genética , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linhagem Celular , Humanos , Queratinócitos/citologia
10.
Orthopade ; 46(7): 617-624, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28194508

RESUMO

Intraarticular fracture of the metacarpophalangeal (MP) joint presents complex problems related to the sophisticated functional aspects of the hand. Injury to the metacarpal head may have a severe effect on hand function but few studies have investigated the management of this condition. In this study, we applied open reduction and internal fixation for the displaced fracture of the metacarpal head and report the clinical and radiographic outcomes of our experience. Thirteen patients (12 men, 1 woman; mean age 21 years) were included in this study, and medical records and radiographs were reviewed retrospectively. The average follow-up period was 12.5 months. Range of motion (ROM) and Disabilities of the Arm, Shoulder, and Hand (DASH) scores were analyzed, and functional results and serial radiographs were investigated for the maintenance of articular congruity and fracture union. The injured fingers were 5 long, 4 small, 2 ring, and 2 index. Five cases were fixed with K­wires, 5 cases with headless screws, and 3 cases with screw and K­wire. The average range of injured MP joint motion was 89°, total active range of motion (TAM) was 265°, and the average DASH score was 3.8 at the last follow-up. All patients showed fracture union on the radiographs and no patient showed significant articular surface incongruence or degenerative change. Open reduction and internal fixation of the metacarpal head fracture had favorable outcomes in our study. The authors suggest accurate reduction and stable fixation for better functional results in metacarpal head fractures.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas Intra-Articulares/cirurgia , Articulação Metacarpofalângica/lesões , Articulação Metacarpofalângica/cirurgia , Metacarpo/lesões , Metacarpo/cirurgia , Adolescente , Adulto , Parafusos Ósseos , Fios Ortopédicos , Criança , Feminino , Seguimentos , Consolidação da Fratura/fisiologia , Humanos , Fraturas Intra-Articulares/diagnóstico por imagem , Fraturas Intra-Articulares/fisiopatologia , Masculino , Articulação Metacarpofalângica/diagnóstico por imagem , Articulação Metacarpofalângica/fisiopatologia , Metacarpo/diagnóstico por imagem , Metacarpo/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Amplitude de Movimento Articular/fisiologia , Estudos Retrospectivos , Adulto Jovem
11.
J Shoulder Elbow Surg ; 25(10): 1704-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27491571

RESUMO

BACKGROUND: Angiofibroblastic changes of a musculotendinous origin at the medial epicondyle characterize medial epicondylitis of the elbow. Although nonsurgical treatment is the primary approach for medial epicondylitis, surgical treatment should be considered when conservative therapy fails. This study reports the results of surgical treatment of medial epicondylitis monitored for more than 5 years. METHODS: This study included 55 patients with 63 cases of medial epicondylitis between 2000 and 2010. The conservative treatment periods lasted for a minimum of 1 year, and steroid injections were administered more than twice before surgery. One surgeon conducted the surgical procedures. The Nirschl and Pettrone grades, visual analog scale (VAS) scores, Disabilities of the Arm, Shoulder and Hand (DASH) scores, Mayo Elbow Performance scores, and grip strengths were analyzed. Statistical analyses were performed using paired t tests. RESULTS: The mean VAS score improved from 8.5 to 2.4 (P <.001). Nirschl and Pettrone grades rated 43% (27 elbows) as excellent and 51% (32 elbows) as good. The Mayo Elbow Performance scores improved from 72 to 88 (P <.001) and DASH scores from 57 to 23 (P <.001). The mean grip strength of the affected side improved from 30 to 43 lb (P <.001). The mean time required to return to work and exercise was 2.8 months and 4.8 months, respectively. One case of heterotrophic ossification, which had no functional instability afterward, was seen. CONCLUSION: The results indicate that surgical treatment of medial epicondylitis could be an effective and safe treatment when conservative treatment fails.


Assuntos
Cotovelo de Tenista/cirurgia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos , Medição da Dor , Estudos Retrospectivos , Cotovelo de Tenista/reabilitação , Resultado do Tratamento
12.
Int J Mol Sci ; 17(11)2016 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-27801787

RESUMO

Ganoderma lucidum, a species of the Basidiomycetes class, has been attracting international attention owing to its wide variety of biological activities and great potential as an ingredient in skin care cosmetics including "skin-whitening" products. However, there is little information available on its inhibitory effect against tyrosinase activity. Therefore, the objectives of this study were to investigate the chemical composition of G. lucidum and its inhibitory effects on melanogenesis. We isolated the active compound from G. lucidum using ethanol extraction and ethyl acetate fractionation. In addition, we assayed its inhibitory effects on tyrosinase activity and melanin biosynthesis in B16F10 melanoma cells. In this study, we identified a bioactive compound, ganodermanondiol, which inhibits the activity and expression of cellular tyrosinase and the expression of tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF), thereby decreasing melanin production. Furthermore, ganodermanondiol also affected the mitogen-activated protein kinase (MAPK) cascade and cyclic adenosine monophosphate (cAMP)-dependent signaling pathway, which are involved in the melanogenesis of B16F10 melanoma cells. The finding that ganodermanondiol from G. lucidum exerts an inhibitory effect on tyrosinase will contribute to the use of this mushroom in the preparation of skin care products in the future.


Assuntos
Lanosterol/análogos & derivados , Melaninas/biossíntese , Melanoma Experimental/tratamento farmacológico , Reishi/química , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon Tipo I/biossíntese , Interferon Tipo I/genética , Lanosterol/administração & dosagem , Lanosterol/química , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Fator de Transcrição Associado à Microftalmia/biossíntese , Fator de Transcrição Associado à Microftalmia/genética , Monofenol Mono-Oxigenase/antagonistas & inibidores , Fosforilação , Plantas Medicinais/química , Proteínas da Gravidez/biossíntese , Proteínas da Gravidez/genética
13.
J Oral Maxillofac Surg ; 73(8): 1592-605, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25976689

RESUMO

PURPOSE: To investigate the 3-dimensional postoperative changes in the proximal segments in patients with facial asymmetry according to the anteroposterior skeletal patterns. MATERIALS AND METHODS: A total of 51 patients with facial asymmetry who had undergone Le Fort I osteotomy and sagittal split ramus osteotomy (SSRO) with rigid fixation were classified according to their anteroposterior skeletal patterns. Cone-beam computed tomography (CBCT) data were obtained before (T0) and 6 months (T1) after surgery. The position, angulation, and distance of the proximal segment were measured from the CBCT superimposition. RESULTS: Comparing the T0 and T1 CBCT data, almost no significant differences were found in the condylar head position in any of the groups (P > .05), except for the axial condylar head position on the deviated side in the skeletal Class I group (P < .05) and the sagittal condylar head position on the deviated side in the skeletal Class III group (P < .05). However, the changes in the coronoid process and ramus down varied (P < .05), and these movements were related to changes in the ramal plane. Comparing the deviated and nondeviated sides, significant differences were found only in the skeletal Class I group (P < .05). CONCLUSIONS: The most influential factors affecting differences between the deviated and nondeviated sides in patients with facial asymmetry after bilateral SSRO could be the direction of the surgical movement of the distal segment of the mandible rather than its extent.


Assuntos
Assimetria Facial/cirurgia , Osteotomia de Le Fort , Osteotomia Sagital do Ramo Mandibular , Adulto , Tomografia Computadorizada de Feixe Cônico , Assimetria Facial/diagnóstico por imagem , Feminino , Humanos , Masculino , Adulto Jovem
14.
Hum Brain Mapp ; 35(9): 4795-804, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24692197

RESUMO

Semantic priming is affected by the degree of association and how readily a word is imagined. In the association effect, activity in the perisylvian structures including the bilateral inferior frontal gyrus, the left middle temporal gyrus, and the supramarginal gyrus was correlated. However, little is known about the brain regions related to the effect of imagery word under the preconscious condition. Forty word pairs for high (HA)-, low (LA)-, and nonassociation (NA), nonword (NW) conditions were presented. Each 40 association word pairs (HA and LA) included 20 high (HI) and 20 low (LI) imagery prime stimuli, using a visually presented lexical decision task. A trial consisted of 30 ms prime, 30 ms mask, 500 ms probe, and 2-8 s stimulus onset asynchrony. Brain activation was measured using functional magnetic resonance imaging during word discrimination. Behavioral data indicated that the shortest response time (RT) was given for HA words, followed by LA and NA, and NW showed the longest RT (P < 0.01). RT was faster in HI than LI within HA, but not LA conditions (P < 0.01). Functional neuroimaging showed that differential brain regions for high imagery (HI) and low imagery (LI) words within low prime-target word association were observed in the left precuneus, left posterior cingulate gyrus, and right cuneal cortex. The present findings demonstrate that the effect of the degree of imagery on semantic priming occurs during the early stage of language processing, indicating an "automatic imagery priming effect." Our paradigm may be useful to explore semantic deficit related to imagery in various psychiatric disorders.


Assuntos
Encéfalo/fisiologia , Imaginação/fisiologia , Priming de Repetição/fisiologia , Semântica , Adulto , Mapeamento Encefálico , Tomada de Decisões/fisiologia , Discriminação Psicológica/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Reconhecimento Visual de Modelos/fisiologia , Tempo de Reação , Leitura
15.
IEEE Robot Autom Lett ; 9(5): 4154-4161, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38550718

RESUMO

Subretinal injection is an effective method for direct delivery of therapeutic agents to treat prevalent subretinal diseases. Among the challenges for surgeons are physiological hand tremor, difficulty resolving single-micron scale depth perception, and lack of tactile feedback. The recent introduction of intraoperative Optical Coherence Tomography (iOCT) enables precise depth information during subretinal surgery. However, even when relying on iOCT, achieving the required micron-scale precision remains a significant surgical challenge. This work presents a robot-assisted workflow for high-precision autonomous needle navigation for subretinal injection. The workflow includes online registration between robot and iOCT coordinates; tool-tip localization in iOCT coordinates using a Convolutional Neural Network (CNN); and tool-tip planning and tracking system using real-time Model Predictive Control (MPC). The proposed workflow is validated using a silicone eye phantom and ex vivo porcine eyes. The experimental results demonstrate that the mean error to reach the user-defined target and the mean procedure duration are within an acceptable precision range. The proposed workflow achieves a 100% success rate for subretinal injection, while maintaining scleral forces at the scleral insertion point below 15mN throughout the navigation procedures.

16.
IEEE Robot Autom Lett ; 9(4): 3807-3814, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-39309968

RESUMO

Retinal surgery is a challenging procedure requiring precise manipulation of the fragile retinal tissue, often at the scale of tens-of-micrometers. Its difficulty has motivated the development of robotic assistance platforms to enable precise motion, and more recently, novel sensors such as microscope integrated optical coherence tomography (OCT) for RGB-D view of the surgical workspace. The combination of these devices opens new possibilities for robotic automation of tasks such as subretinal injection (SI), a procedure that involves precise needle insertion into the retina for targeted drug delivery. Motivated by this opportunity, we develop a framework for autonomous needle navigation during SI. We develop a system which enables the surgeon to specify waypoint goals in the microscope and OCT views, and the system autonomously navigates the needle to the desired subretinal space in real-time. Our system integrates OCT and microscope images with convolutional neural networks (CNNs) to automatically segment the surgical tool and retinal tissue boundaries, and model predictive control that generates optimal trajectories that respect kinematic constraints to ensure patient safety. We validate our system by demonstrating 30 successful SI trials on pig eyes. Preliminary comparisons to a human operator in robot-assisted mode highlight the enhanced safety and performance of our system.

17.
Commun Biol ; 7(1): 1289, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39384879

RESUMO

Polygenic risk score (PRS) and rare monogenic variant screening are valuable tools for predicting cancer risk and identifying individuals at high risk. Integrating both common and rare genetic variants is crucial for accurate risk assessment. However, estimating the impacts of rare variants on cancer and combining them with PRS remains challenging. Here, we analyze 454,711 exome sequencing and 487,409 array UK Biobank samples, focusing on breast and prostate cancers. We introduce an expanded PRS (EPRS) approach, yielding a systematic model for more effective risk stratification. By prioritizing and clustering genes with cancer-specific rare variants based on odds ratios and population-attributable fraction, we refine risk stratification by combining both monogenic and polygenic effects. Individuals in high-PRS groups with rare high-impact gene variants show up to 15- and 22-fold higher risk for breast and prostate cancers, respectively, compared to those in the intermediate-PRS groups without rare variants. Combined risk profiles vary across distinct rare variant clusters within the same PRS group for both cancers. Our EPRS approach enhances risk stratification for breast and prostate cancers, offering important insights for future research and potential applications to other cancer types.


Assuntos
Neoplasias da Mama , Predisposição Genética para Doença , Herança Multifatorial , Neoplasias da Próstata , Humanos , Neoplasias da Próstata/genética , Neoplasias da Mama/genética , Neoplasias da Mama/epidemiologia , Masculino , Feminino , Medição de Risco , Fatores de Risco , Família Multigênica
18.
J Pers Med ; 14(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38673032

RESUMO

Obesity negatively affects hemodynamics and cerebral physiology. We investigated the effect of the utilization of an intermittent pneumatic compression (IPC) device on hemodynamics and cerebral physiology in patients undergoing laparoscopic bariatric surgery under general anesthesia with lung-protective ventilation. Sixty-four patients (body mass index > 30 kg/m2) were randomly assigned to groups that received an IPC device (IPC group, n = 32) and did not (control group, n = 32). The mean arterial pressure (MAP), heart rate (HR), need for vasopressors, cerebral oxygen saturation (rSO2), and cerebral desaturation events were recorded. The incidence of intraoperative hypotension was not significantly different between groups (p = 0.153). Changes in MAP and HR over time were similar between groups (p = 0.196 and p = 0.705, respectively). The incidence of intraoperative cerebral desaturation was not significantly different between groups (p = 0.488). Changes in rSO2 over time were similar between the two groups (p = 0.190) during pneumoperitoneum. Applying IPC to patients with obesity in the steep reverse Trendelenburg position may not improve hemodynamic parameters, vasopressor requirements, or rSO2 values during pneumoperitoneum under lung-protective ventilation. During laparoscopic bariatric surgery, IPC alone has limitations in improving hemodynamics and cerebral physiology.

19.
IEEE Int Conf Robot Autom ; 2024: 8209-8215, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39421218

RESUMO

A surgeon's physiological hand tremor can significantly impact the outcome of delicate and precise retinal surgery, such as retinal vein cannulation (RVC) and epiretinal membrane peeling. Robot-assisted eye surgery technology provides ophthalmologists with advanced capabilities such as hand tremor cancellation, hand motion scaling, and safety constraints that enable them to perform these otherwise challenging and high-risk surgeries with high precision and safety. Steady-Hand Eye Robot (SHER) with cooperative control mode can filter out surgeon's hand tremor, yet another important safety feature, that is, minimizing the contact force between the surgical instrument and sclera surface for avoiding tissue damage cannot be met in this control mode. Also, other capabilities, such as hand motion scaling and haptic feedback, require a teleoperation control framework. In this work, for the first time, we implemented a teleoperation control mode incorporated with an adaptive sclera force control algorithm using a PHANTOM Omni haptic device and a force-sensing surgical instrument equipped with Fiber Bragg Grating (FBG) sensors attached to the SHER 2.1 end-effector. This adaptive sclera force control algorithm allows the robot to dynamically minimize the tool-sclera contact force. Moreover, for the first time, we compared the performance of the proposed adaptive teleoperation mode with the cooperative mode by conducting a vessel-following experiment inside an eye phantom under a microscope.

20.
NPJ Digit Med ; 7(1): 295, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39433945

RESUMO

Increasing interest in applying large language models (LLMs) to medicine is due in part to their impressive performance on medical exam questions. However, these exams do not capture the complexity of real patient-doctor interactions because of factors like patient compliance, experience, and cognitive bias. We hypothesized that LLMs would produce less accurate responses when faced with clinically biased questions as compared to unbiased ones. To test this, we developed the BiasMedQA dataset, which consists of 1273 USMLE questions modified to replicate common clinically relevant cognitive biases. We assessed six LLMs on BiasMedQA and found that GPT-4 stood out for its resilience to bias, in contrast to Llama 2 70B-chat and PMC Llama 13B, which showed large drops in performance. Additionally, we introduced three bias mitigation strategies, which improved but did not fully restore accuracy. Our findings highlight the need to improve LLMs' robustness to cognitive biases, in order to achieve more reliable applications of LLMs in healthcare.

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