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1.
Toxicol Appl Pharmacol ; 476: 116675, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37661062

RESUMO

Methodical screening of safe and efficient drug candidate compounds is crucial for drug development. A high-throughput and accurate compound evaluation method targeting the central nervous system can be developed using in vitro neural networks. In particular, an evaluation system based on a human-derived neural network that can act as an alternative to animal experiments is desirable to avoid interspecific differences. A microelectrode array (MEA) is one such evaluation system, and can measure in vitro neural activity; however, studies on compound evaluation criteria and in vitro to in vivo extrapolation are scarce. In this study, we identified the parameters that can eliminate the effects of solvents from neural activity data obtained using MEA allow for accurate compound evaluation. Additionally, we resolved the issue associated with compound evaluation criteria during MEA using principal component analysis by considering the neuronal activity exceeding standard deviation (SD) of the solvent as indicator of seizurogenic potential. Overall, 10 seizurogenic compounds and three negative controls were assessed using MEA-based co-cultured human-induced pluripotent stem cell-derived neurons and astrocytes, and primary rat cortical neurons. In addition, we determined rat cerebrospinal fluid (CSF) concentrations during tremor and convulsion in response to exposure to test compounds. To characterize the in vitro to in vivo extrapolation and species differences, we compared the concentrations at which neuronal activity exceeding the SD range of the solvent was detectable using the MEA system and rat CSF concentration.


Assuntos
Astrócitos , Células-Tronco Pluripotentes Induzidas , Humanos , Animais , Ratos , Neurônios , Convulsões , Solventes
2.
Sci Rep ; 12(1): 2281, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-35145132

RESUMO

In vitro microelectrode array (MEA) assessment using human induced pluripotent stem cell (iPSC)-derived neurons holds promise as a method of seizure and toxicity evaluation. However, there are still issues surrounding the analysis methods used to predict seizure and toxicity liability as well as drug mechanisms of action. In the present study, we developed an artificial intelligence (AI) capable of predicting the seizure liability of drugs and identifying drugs using deep learning based on raster plots of neural network activity. The seizure liability prediction AI had a prediction accuracy of 98.4% for the drugs used to train it, classifying them correctly based on their responses as either seizure-causing compounds or seizure-free compounds. The AI also made concentration-dependent judgments of the seizure liability of drugs that it was not trained on. In addition, the drug identification AI implemented using the leave-one-sample-out scheme could distinguish among 13 seizure-causing compounds as well as seizure-free compound responses, with a mean accuracy of 99.9 ± 0.1% for all drugs. These AI prediction models are able to identify seizure liability concentration-dependence, rank the level of seizure liability based on the seizure liability probability, and identify the mechanism of the action of compounds. This holds promise for the future of in vitro MEA assessment as a powerful, high-accuracy new seizure liability prediction method.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Responsabilidade Legal , Aprendizado de Máquina , Redes Neurais de Computação , Preparações Farmacêuticas , Convulsões/induzido quimicamente , Testes de Toxicidade/métodos , Adulto , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Previsões , Humanos , Células-Tronco Pluripotentes Induzidas , Masculino , Microeletrodos , Pessoa de Meia-Idade
3.
Toxicol Sci ; 184(2): 265-275, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34570236

RESUMO

Screening for drug discovery targeting the central nervous system requires the establishment of efficient and highly accurate toxicity test methods that can reduce costs and time while maintaining high throughput using the function of an in vitro neural network. In particular, an evaluation system using a human-derived neural network is desirable in terms of species difference. Despite the attention, the microelectrode array (MEA) is attracting among the evaluation systems that can measure in vitro neural activity, an effective analysis method for evaluation of toxicity and mechanism of action has not yet been established. Here we established analytical parameters and multivariate analysis method capable of detecting seizure liability of drugs using MEA measurement of human iPS cell-derived neurons. Using the spike time series data of all drugs, we established periodicity as a new analytical parameter. Periodicity has facilitated the detection of responses to seizurogenic drugs, previously difficult to detect with conventional analytical parameters. By constructing a multivariate analytical method that identifies a parameter set that achieves an arbitrary condition, we found that the parameter set comprising total spikes, maximum frequency (MF), inter- MF interval (IMFI), coefficient of variance of IMFI, and periodicity can uniformly detect the seizure liability of seizurogenic drugs with different mechanisms of action. Seizurogenic drugs were suggested to increase the regularity of the network burst in MEA measurements in human iPS cell-derived neurons.


Assuntos
Células-Tronco Pluripotentes Induzidas , Potenciais de Ação , Células Cultivadas , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Microeletrodos , Neurônios , Análise de Componente Principal , Convulsões/induzido quimicamente
4.
Dis Esophagus ; 32(11)2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-30791046

RESUMO

The distribution of mediastinal lymph node metastasis in patients with adenocarcinoma of the esophagogastric junction (AEG) remains unclear. Additionally, the distribution of nodal mediastinal metastasis from squamous cell carcinoma (SCC) of the lower esophagus with involvement of the esophagogastric junction remains unclear, given the very limited number of these patients. In this retrospective review, we compared the outcomes of radical lymphadenectomy of the mediastinum, including upper mediastinal lymphadenectomy, between patients with AEG and those with SCC. From 2005 to 2017, 69 consecutive patients underwent esophagectomy via right thoracotomy or minimally invasive esophagectomy for a Siewert type I or II tumor with esophageal invasion ≥3 cm. We analyzed the incidences of mediastinal lymph node metastasis in this group relative to those of 73 patients with SCC with involvement of the esophagogastric junction who consecutively underwent esophagectomy during the same period. Mediastinal lymph node metastasis was seen in 26 of 69 patients with AEG (38%), with upper, middle, lower mediastinal nodal metastasis instances of 20%, 17%, and 23%, respectively. Mediastinal lymph node metastasis was seen in 23 of 73 patients with SCC (32%), with upper, middle, lower mediastinal nodal metastasis instances of 12%, 16%, and 19%, respectively. This mediastinal lymph nodal metastasis distribution did not statistically differ between patients with AEG and those with SCC. The relapse-free survival outcomes were poor for patients with clinical (P < 0.01) or pathological (P < 0.01) nodal metastasis of the mediastinum with AEG. In contrast, patients with clinical or pathological mediastinal nodal metastases of SCC did not have extremely poor survival outcomes, compared to patients with AEG. Despite the limited dataset available for analysis, patients with AEG and those with SCC might exhibit similar incidences and distribution of mediastinal lymph node metastasis. However, the clinical or pathological metastasis of AEG to the mediastinum was associated with poor survival outcomes, even if radical mediastinal lymphadenectomy including the upper mediastinal lymphadenectomy was performed.


Assuntos
Adenocarcinoma/secundário , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/secundário , Junção Esofagogástrica , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Neoplasias Esofágicas/cirurgia , Carcinoma de Células Escamosas do Esôfago/cirurgia , Esofagectomia , Feminino , Humanos , Excisão de Linfonodo , Metástase Linfática , Masculino , Mediastino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos , Taxa de Sobrevida
5.
Br J Surg ; 105(13): 1793-1798, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30106170

RESUMO

BACKGROUND: Treatment of supraclavicular nodes remains controversial among patients with oesophageal squamous cell carcinoma. This study assessed the outcomes of patients who underwent oesophagectomy with or without supraclavicular lymphadenectomy after neoadjuvant treatment. METHODS: This was a single-centre retrospective cohort study. Patients with oesophageal squamous cell carcinoma and clinically negative supraclavicular nodes who underwent oesophagectomy after neoadjuvant treatment between January 2005 and December 2015 were included. Overall and relapse-free survival were compared between patients who did or did not undergo supraclavicular nodal dissection. Propensity score matching was used to correct for differences in prognostic factors between the groups. RESULTS: Some 223 patients underwent supraclavicular lymphadenectomy. The prevalence of pathologically confirmed supraclavicular metastasis was 10·3 per cent, and these patients had poor 5-year relapse-free (7 per cent) and overall (14 per cent) survival. Only two of 55 patients who did not undergo supraclavicular lymphadenectomy had recurrent disease in the supraclavicular region without distant metastasis. There was no statistically significant difference between the groups in relapse-free survival (hazard ratio (HR) 0·95, 95 per cent c.i. 0·61 to 1·47; P = 0·821) or overall survival (HR 0·86, 0·52 to 1·40; P = 0·544). Similarly, no significant difference in relapse-free or overall survival was observed between the propensity score-matched groups. CONCLUSION: For patients with clinically negative supraclavicular lymph nodes, prophylactic supraclavicular lymphadenectomy may be omitted when neoadjuvant treatment is administered.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Excisão de Linfonodo/métodos , Adulto , Idoso , Carcinoma de Células Escamosas/mortalidade , Intervalo Livre de Doença , Neoplasias Esofágicas/mortalidade , Esofagectomia/mortalidade , Feminino , Humanos , Japão/epidemiologia , Estimativa de Kaplan-Meier , Excisão de Linfonodo/mortalidade , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estudos Retrospectivos
6.
Dis Esophagus ; 30(9): 1-8, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28859367

RESUMO

Neoadjuvant treatment has become standard care for patients with resectable esophageal cancer. However, some patients cannot undergo surgery or curative resection because of disease progression during neoadjuvant treatment. The aim of this study is to identify the pretreatment characteristics of patients in whom neoadjuvant treatment failed. The study enrolled 231 patients who underwent chemotherapy with cisplatin and 5-fluorouracil (CF) as neoadjuvant therapy for T1N1-3 or T2-3 any-N esophageal squamous cell carcinoma (ESCC). Of these patients, 201 (87.0%) underwent curative resection (R0) and 30 (13.0%) could not undergo curative resection; 19 patients (8.2%) underwent incomplete resection (R1 or R2), and 11 patients (4.8%) could not undergo surgery because of disease progression. We compared clinical characteristics and survival between patients who underwent curative resection (curative group) and those who could not undergo curative resection (noncurative group) to determine the factors predicting noncurative treatment. The noncurative group had significantly worse disease-specific survival than the curative group (P < 0.001). All patients in the noncurative group had cT3 tumors. In 141 patients with cT3 tumors, those in the noncurative group were more likely to have higher serum SCC antigen concentration (P = 0.021), location of the main tumor in the upper to the middle third of the esophagus (P = 0.071), intramural metastases (P < 0.001), advanced N category (P = 0.016), and bulky lymph node metastases (P = 0.060). Multivariate logistic regression analysis identified location of the main tumor in the upper to the middle third of the esophagus (P = 0.047), intramural metastases (P = 0.002), and nodal metastases (N1, P = 0.014; N2, P = 0.015, respectively) as independent predictors of treatment failure in patients with cT3 tumors. Neoadjuvant CF therapy alone may not be effective for patients with cT3 tumors accompanied by these risk factors, and the efficacy of alternative strategies, such as triplet chemotherapy or chemoradiotherapy, should be evaluated.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/cirurgia , Idoso , Antígenos de Neoplasias/sangue , Carcinoma de Células Escamosas/secundário , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Progressão da Doença , Neoplasias Esofágicas/patologia , Esofagectomia , Feminino , Fluoruracila/administração & dosagem , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Estudos Retrospectivos , Serpinas/sangue , Taxa de Sobrevida , Falha de Tratamento , Carga Tumoral
8.
Dalton Trans ; 44(41): 18090-100, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26417921

RESUMO

A monooxotungsten(iv) benzenedithiolate complex containing two intramolecular NHS hydrogen bonds, (NEt4)2[W(IV)O(1,2-S2-3-t-BuNHCOC6H3)2] (1-W), was synthesized via a ligand-exchange reaction between a new starting complex, (NEt4)2[W(IV)O(SC6F5)4], and a partially deprotonated dithiol. When dithiol was used in solution, the oxo ligand was protonated and removed to afford (NEt4)2[W(IV)(1,2-S2-3-t-BuNHCOC6H3)3]. The trans isomer, trans-1-W, was crystallized, and the molecular structure was determined via X-ray analysis. Trans-1-W was gradually isomerized by heating it in solution and it eventually achieved an approximately 1 : 1 mixture of trans/cis isomers after 48 days. However, a slightly excess amount of trans isomer remained, so the isomerization rate was considerably slower than that of the molybdenum analogue. In the presence of NEt4BH4, deuteration of the NH protons was observed in acetonitrile-d3. The oxidation of both trans- and cis-1-W by Me3NO afforded the corresponding dioxotungsten(vi) complex, (NEt4)2[W(VI)O2(1,2-S2-3-t-BuNHCOC6H3)2] (2-W), as a single isomer. The contributions of the NHS hydrogen bonds to the bond distances, vibrational data, and electrochemical properties are described via comparisons with their molybdenum analogues. The results of this comparative study yielded insights into both tungsten and molybdenum enzymes.


Assuntos
Derivados de Benzeno/química , Molibdênio/química , Compostos Organometálicos/química , Oxigênio/química , Tungstênio/química , Cristalografia por Raios X , Ligação de Hidrogênio , Isomerismo , Ligantes , Modelos Moleculares , Oxirredução , Compostos de Sulfidrila/química , Tolueno/análogos & derivados , Tolueno/química
9.
Tissue Antigens ; 86(3): 164-71, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26216489

RESUMO

Here, we describe an human leukocyte antigen (HLA)-A*24:02-restricted cytotoxic T-lymphocyte (CTL) clone, 1G3, established from naïve CD8(+) T-lymphocytes obtained from a healthy donor stimulated with HLA-modified TOV21G, an ovarian cancer cell line. The 1G3 clone responds not only to ovarian cancer cells in the context of HLA-A*24:02 but also to allogeneic HLA-Cw*07:02 molecules through cross-reactive T-cell receptor recognition. Expression screening using a complementary DNA library constructed from TOV21G messenger RNA revealed that this alloreactivity was mediated through the nine-mer peptide VRTPYTMSY, derived from RNA-binding motif protein 4. To our knowledge, this study presents the first example of the allorecognition of an HLA-Cw molecule by HLA-A-restricted T-cells, thereby revealing a naturally processed epitope peptide. These findings provide the structural bases for the allorecognition of human T-cells. In addition, this study suggests that unexpected alloresponses occur in certain HLA combinations, and further study is needed to understand the mechanisms of alloreactivity for better prediction of alloresponses in clinical settings.


Assuntos
Reações Cruzadas/imunologia , Antígeno HLA-A24/imunologia , Antígenos HLA-C/imunologia , Neoplasias Ovarianas/imunologia , Peptídeos/metabolismo , Processamento de Proteína Pós-Traducional , Linfócitos T Citotóxicos/imunologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Linhagem Celular Tumoral , Células Clonais , DNA Complementar/genética , Epitopos/imunologia , Feminino , Células HEK293 , Humanos , Dados de Sequência Molecular , Neoplasias Ovarianas/patologia , Peptídeos/química , Ligação Proteica , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo
10.
J Dent Res ; 94(2): 289-96, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25503612

RESUMO

Various chemotherapeutic agents used in patients with hematopoietic malignancy cause serious side effects, including myelosuppression and immunosuppression. Immunosuppression makes patients more susceptible to infection, resulting in an increased risk of infectious complications, including the development of severe septicemia that may be life-threatening. It is necessary for dental staff to be familiar with an appropriate protocol in such cases and to share information about the chemotherapy with a hematologist. To verify the effectiveness of our dental intervention protocol, we conducted a prospective study on the incidence of complications for each myelosuppressive grade of chemotherapy in patients with hematopoietic malignancy. We compared the incidence of complications between treatment P (patients who finished all the dental treatments according to the protocol) and treatment Q (patients who did not) per grade (A, B, C, D) and incidence of systemic or oral findings. We also compared the incidence of oral complication related to the residual teeth between first chemo (patients who were undergoing chemotherapy for the first time) and prior chemo (not the first time). There were significant differences in inflammatory complications between treatment P and treatment Q. We found that both systemic and oral inflammatory complications increased with higher-grade myelosuppressive chemotherapy. Additionally, there was a significant difference between the incidence of oral complications related to the residual teeth between first chemo and prior chemo. Complete implementation of the dental intervention protocol was associated with fewer oral and systemic infectious and inflammatory complications in patients with hematopoietic malignancies undergoing chemotherapy. The incidence of oral and systemic complications also increased with grade of chemotherapy. These results support the validity of our dental intervention protocol. We should pay close attention to the oral state of de novo hematopoietic malignancy patients.


Assuntos
Antineoplásicos/efeitos adversos , Assistência Odontológica para Doentes Crônicos , Neoplasias Hematológicas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Medula Óssea/efeitos dos fármacos , Protocolos Clínicos , Cárie Dentária/terapia , Prótese Dentária , Feminino , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/efeitos adversos , Higiene Bucal , Doenças Periodontais/terapia , Estudos Prospectivos , Extração Dentária , Adulto Jovem
11.
Gene Ther ; 21(6): 575-84, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24694533

RESUMO

The genetic transfer of T-cell receptors (TCRs) directed toward target antigens into T lymphocytes has been used to generate antitumor T cells efficiently without the need for the in vitro induction and expansion of T cells with cognate specificity. Alternatively, T cells have been gene-modified with a TCR-like antibody or chimeric antigen receptor (CAR). We show that immunization of HLA-A2 transgenic mice with tetramerized recombinant HLA-A2 incorporating HA-1 H minor histocompatibility antigen (mHag) peptides and ß2-microglobulin (HA-1 H/HLA-A2) generate highly specific antibodies. One single-chain variable region moiety (scFv) antibody, #131, demonstrated high affinity (KD=14.9 nM) for the HA-1 H/HLA-A2 complex. Primary human T cells transduced with #131 scFV coupled to CD28 transmembrane and CD3ζ domains were stained with HA-1 H/HLA-A2 tetramers slightly more intensely than a cytotoxic T lymphocyte (CTL) clone specific for endogenously HLA-A2- and HA-1 H-positive cells. Although #131 scFv CAR-T cells required >100-fold higher antigen density to exert cytotoxicity compared with the cognate CTL clone, they could produce inflammatory cytokines against cells expressing HLA-A2 and HA-1 H transgenes. These data implicate that T cells with high-affinity antigen receptors reduce the ability to lyse targets with low-density peptide/MHC complexes (~100 per cell), while they could respond at cytokine production level.


Assuntos
Antígeno HLA-A2/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Proteínas Recombinantes/imunologia , Linfócitos T/fisiologia , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Sequência de Bases , Linfócitos T CD4-Positivos/imunologia , Antígenos CD8/metabolismo , Epitopos/imunologia , Humanos , Camundongos Knockout , Camundongos Transgênicos , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia , Linfócitos T Citotóxicos/imunologia , Microglobulina beta-2/genética
12.
Clin Exp Immunol ; 173(2): 268-75, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23607494

RESUMO

Biliary atresia (BA) is thought to be associated with infections by viruses such as Reoviridae and is characterized histologically by fibrosclerosing cholangitis with proinflammatory cytokine-mediated inflammation. Interleukin (IL)-32 affects the continuous inflammation by increasing the production of proinflammatory cytokines. In this study, the role of IL-32 in the cholangitis of BA was examined. Immunohistochemistry for IL-32 and caspase 1 was performed using 21 samples of extrahepatic bile ducts resected from BA patients. Moreover, using cultured human biliary epithelial cells (BECs), the expression of IL-32 and its induction on stimulation with a Toll-like receptor [(TLR)-3 ligand (poly(I:C)] and proinflammatory cytokines was examined. BECs composing extrahepatic bile ducts showing cholangitis expressed IL-32 in BA, but not in controls. Caspase 1 was expressed constantly on BECs of both BA and control subjects. Furthermore, poly(I:C) and proinflammatory cytokines [(IL-1ß, interferon (IFN)-γ and tumour necrosis factor (TNF)-α] induced IL-32 expression strongly in cultured BECs, accompanying the constant expression of TLR-3 and caspase 1. Our results imply that the expression of IL-32 in BECs was found in the damaged bile ducts of BA and induced by biliary innate immunity via TLR-3 and proinflammatory cytokines. These findings suggest that IL-32 is involved initially in the pathogenic mechanisms of cholangitis in BA and also plays an important role in the amplification and continuance of periductal inflammatory reactions. It is therefore tempting to speculate that inhibitors of IL-32 could be useful for attenuating cholangitis in BA.


Assuntos
Ductos Biliares/imunologia , Atresia Biliar/imunologia , Colangite/imunologia , Células Epiteliais/imunologia , Interleucinas/metabolismo , Ductos Biliares/patologia , Caspase 1/genética , Caspase 1/metabolismo , Células Cultivadas , Feminino , Humanos , Imunidade Inata , Imuno-Histoquímica , Lactente , Recém-Nascido , Mediadores da Inflamação/metabolismo , Interleucinas/genética , Masculino , Poli I-C/imunologia , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , Regulação para Cima
13.
IEEE Trans Haptics ; 6(2): 156-66, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24808300

RESUMO

Development of tactile displays to enhance palpation of lumps during robot-assisted minimally invasive surgery is challenging due to size and weight constraints, motivating a pneumatic actuation strategy. This work describes the quantitative and psychophysical assessment of an air-jet tactile display that creates a lump percept by directing pressurized air through an aperture onto the finger. The air pressure and aperture size are meant to control the hardness and size, respectively, of the perceived lump. Jet impingement pressure and flow rate were measured by capacitive tactile sensors and mass flow meters at varying aperture sizes and pressures. The air-jet pressure profile width evolves as jet theory predicts and is largely independent of supply pressure (and therefore jet exit velocity). The method of constant stimuli was used to determine the just noticeable differences (JNDs) for the air pressure and aperture size. Qualitative results indicate that subjects perceive the stimulus as a "lump-like" shape. Pressure JNDs ranged from 19.6-24.4 kPag and aperture size JNDs ranged from 0.50-0.66 mm. No significant correlation exists between the supply pressure and changes in perceived lump size. However, pressure JNDs show significant (p < 0.001) inverse correlation with aperture size, with improved discrimination at larger apertures, where a greater finger pad area is stimulated.


Assuntos
Pressão do Ar , Palpação/instrumentação , Procedimentos Cirúrgicos Robóticos/instrumentação , Limiar Diferencial , Dedos/fisiologia , Humanos , Patologia Clínica , Psicofísica/métodos , Tato
14.
Tissue Antigens ; 80(2): 119-25, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22568758

RESUMO

Minor histocompatibility (H) antigens are targets of graft-vs-host disease and graft-vs-tumor responses after human leukocyte antigen matched allogeneic hematopoietic stem cell transplantation. Recently, we reported a strategy for genetic mapping of linkage disequilibrium blocks that encoded novel minor H antigens using the large dataset from the International HapMap Project combined with conventional immunologic assays to assess recognition of HapMap B-lymphoid cell line by minor H antigen-specific T cells. In this study, we have constructed and provide an online interactive program and demonstrate its utility for searching for single-nucleotide polymorphisms (SNPs) responsible for minor H antigen generation. The website is available as 'HapMap SNP Scanner', and can incorporate T-cell recognition and other data with genotyping datasets from CEU, JPT, CHB, and YRI to provide a list of candidate SNPs that correlate with observed phenotypes. This method should substantially facilitate discovery of novel SNPs responsible for minor H antigens and be applicable for assaying of other specific cell phenotypes (e.g. drug sensitivity) to identify individuals who may benefit from SNP-based customized therapies.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Teste de Histocompatibilidade/métodos , Antígenos de Histocompatibilidade Menor/imunologia , Polimorfismo de Nucleotídeo Único , Software , Linfócitos B/imunologia , Linhagem Celular , Mapeamento Cromossômico , Mineração de Dados , Genótipo , Projeto HapMap , Humanos , Internet , Desequilíbrio de Ligação , Antígenos de Histocompatibilidade Menor/genética , Fenótipo , Linfócitos T/imunologia , Transplante Homólogo
16.
Int J Rob Res ; 29(13): 1640-1660, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21170164

RESUMO

The tip asymmetry of a bevel-tip needle results in the needle naturally bending when it is inserted into soft tissue. This enables robotic needle steering, which can be used in medical procedures to reach subsurface targets inaccessible by straight-line trajectories. However, accurate path planning and control of needle steering requires models of needle-tissue interaction. Previous kinematic models required empirical observations of each needle and tissue combination in order to fit model parameters. This study describes a mechanics-based model of robotic needle steering, which can be used to predict needle behavior and optimize system design based on fundamental mechanical and geometrical properties of the needle and tissue. We first present an analytical model for the loads developed at the tip, based on the geometry of the bevel edge and material properties of soft-tissue simulants (gels). We then present a mechanics-based model that calculates the deflection of a bevel-tipped needle inserted through a soft elastic medium. The model design is guided by microscopic observations of needle-gel interactions. The energy-based formulation incorporates tissue-specific parameters, and the geometry and material properties of the needle. Simulation results follow similar trends (deflection and radius of curvature) to those observed in experimental studies of robotic needle insertion.

17.
Transplant Proc ; 42(7): 2740-4, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20832579

RESUMO

BACKGROUND: We examined the relationship between the improved physical activity by early rehabilitation and the duration of hospitalization among patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: Thirteen allo-HSCT patients with myeloablative conditioning regimens (group A) and 13 patients with nonmyeloablative conditioning regimens (group B) were assessed retrospectively in this study. All patients received physical exercise immediately after neutrophil engraftment at the class 10,000 bioclean room (class 10,000). The mean daily steps at class 10,000 were measured as a substitute for the amount of physical activity, and the duration of hospitalization as one of the clinical outcomes. RESULTS: The degree of physical activity showed a negative correlation with the duration of hospitalization in group A (r = -.71; P = .0071), regardless of complications such as acute graft-versus-host disease, infections, and cytomegalovirus reactivation. However, there was no significant association in group B (r = .09; P = .77). CONCLUSION: The improved physical activity through early rehabilitation may be an independent, favorable prognostic factor for allo-HSCT patients with myeloablative conditioning regimens.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adulto , Anemia Aplástica/reabilitação , Anemia Aplástica/cirurgia , Anemia Aplástica/terapia , Infecções por Citomegalovirus/epidemiologia , Terapia por Exercício , Feminino , Doença Enxerto-Hospedeiro/epidemiologia , Humanos , Infecções/epidemiologia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/reabilitação , Síndromes Mielodisplásicas/cirurgia , Síndromes Mielodisplásicas/terapia , Neoplasias/reabilitação , Neoplasias/cirurgia , Neoplasias/terapia , Condicionamento Pré-Transplante/métodos , Transplante Homólogo/reabilitação
19.
Transplant Proc ; 41(9): 3873-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19917404

RESUMO

To prevent acute graft-versus-host disease (GVHD), mycophenolate mofetil (MMF) combined with calcineurin inhibitors have been used in allogeneic hematopoietic stem cell transplantation (allo-SCT). Previous studies commonly utilize MMF treatment until day 30 after allo-SCT. However, the feasibility of continuous administration after day 30 has not been well evaluated. We retrospectively assessed the safety and efficacy of extended drug administration. Twenty-five patients ceased MMF at day 30 (group A); whereas, 16 patients (group B) received extended regimens depending on individual risk factors for GVHD. No severe adverse events were observed in either group. Although the cumulative incidence (CI) of grade I to IV GVHD at day 100 was comparable between the 2 groups, the CI of grade II to IV GVHD was less among group B (12.5%) compared with group A (42.3%). Extended MMF administration may be safe and beneficial as preemptive therapy to reduce the development of moderate-to-severe acute GVHD.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Ácido Micofenólico/análogos & derivados , Adulto , Idoso , Ciclosporina/uso terapêutico , Esquema de Medicação , Feminino , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Leucemia/tratamento farmacológico , Leucemia/cirurgia , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/uso terapêutico , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/cirurgia , Segurança , Tacrolimo/uso terapêutico , Fatores de Tempo , Transplante Homólogo , Adulto Jovem
20.
Med Eng Phys ; 31(2): 195-206, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18815068

RESUMO

Realistic modeling of medical interventions involving tool-tissue interactions has been considered to be a key requirement in the development of high-fidelity simulators and planners. Organ geometry, soft-tissue constitutive laws, and boundary conditions imposed by the connective tissues surrounding the organ are some of the factors that govern the accuracy of medical intervention planning. In this study it is demonstrated that, for needle path planning, the organ geometry and boundary constraints surrounding the organ are the most important factors influencing the deformation. As an example, the procedure of needle insertion into the prostate (e.g. for biopsy or brachytherapy) is considered. Image segmentation is used to extract the anatomical details from magnetic resonance images, while object-oriented finite element analysis (OOF) software is used to generate finite element (FE) meshes from the segmented images. Two-dimensional FE simulations that account for complex anatomical details along with relative motion between the prostate and its surrounding structure using cohesive zone models are compared with traditional simulation models having simple organ geometry and boundary constraints. Nodal displacements for these simpler models were observed to be up to 14 times larger than those obtained from the anatomically accurate models.


Assuntos
Análise de Elementos Finitos , Modelos Anatômicos , Biópsia , Humanos , Masculino , Próstata/anatomia & histologia , Bexiga Urinária/anatomia & histologia
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