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1.
Leuk Lymphoma ; : 1-9, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38475670

RESUMO

Cytomegalovirus (CMV) reactivation increases treatment-related mortality (TRM) after allogeneic hematopoietic cell transplantation (allo-HCT). We analyzed 141 adult acute leukemia (AL) patients suffered allo-HCT between 2017 and 2021, who developed CMV viremia post-HCT and treated with valganciclovir or foscarnet, to evaluate effectiveness and safety of both drugs. Viremia clearance rates (14 and 21 d post treatment) and toxicities were similar in two groups. However, valganciclovir was associated with a lower cumulative incidence of CMV recurrence within 180 days (16.7% vs. 35.7%, p=0.029) post CMV clearance. Finally, 2-year TRM was lower in valganciclovir group (9.7% ± 0.2% vs. 26.2% ± 0.3%, p = 0.026), result a superior 2-year overall survival (OS; 88.1% ± 5.2% vs. 64.4% ± 5.5%, p = 0.005) and leukemia-free survival (LFS; 82.0% ± 5.9% vs. 58.9% ± 5.6%, p = 0.009). Valganciclovir might decrease CMV viremia recurrence and led to better long-term outcome than foscarnet in adult AL patients developed CMV viremia post-HCT. Considering the inherent biases of retrospective study, well-designed trials are warranted to validate our conclusion.

2.
J Electromyogr Kinesiol ; 75: 102864, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38310768

RESUMO

Advanced single-use dynamic EMG-torque models require burdensome subject-specific calibration contractions and have historically been assumed to produce lower error than generic models (i.e., models that are identical across subjects and muscles). To investigate this assumption, we studied generic one degree of freedom (DoF) models derived from the ensemble median of subject-specific models, evaluated across subject, DoF and joint. We used elbow (N = 64) and hand-wrist (N = 9) datasets. Subject-specific elbow models performed statistically better [5.79 ± 1.89 %MVT (maximum voluntary torque) error] than generic elbow models (6.21 ± 1.85 %MVT error). However, there were no statistical differences between subject-specific vs. generic models within each hand-wrist DoF. Next, we evaluated generic models across joints. The best hand-wrist generic model had errors of 6.29 ± 1.85 %MVT when applied to the elbow. The elbow generic model had errors of 7.04 ± 2.29 %MVT when applied to the hand-wrist. The generic elbow model was statistically better in both joints, compared to the generic hand-wrist model. Finally, we tested Butterworth filter models (a simpler generic model), finding no statistical differences between optimum Butterworth and subject-specific models. Overall, generic models simplified EMG-torque training without substantive performance degradation and provided the possibility of transfer learning between joints.


Assuntos
Articulação do Cotovelo , Músculo Esquelético , Humanos , Músculo Esquelético/fisiologia , Eletromiografia , Torque , Cotovelo/fisiologia , Articulação do Cotovelo/fisiologia , Articulações
3.
Mol Pharm ; 21(3): 1342-1352, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38295278

RESUMO

Rift Valley fever virus (RVFV) could cause an emergency illness characterized by fever, muscle pain, and even death in humans or ruminants. However, there are no approved antiviral drugs that prevent or treat RVFV infection. While therapeutic antibodies have shown promising potential for prevention or treatment in several studies, many studies are ongoing, especially in the field of infectious diseases. Among these studies, the mRNA-LNP platform shows great potential for application, following the COVID-19 pandemic. Previously, we have obtained a neutralizing antibody against RVFV, which was named A38 protein and verified to have a high binding and neutralization ability. In this study, we aimed to identify an effectively optimized sequence and expressed the prioritized mRNA-encoded antibody in vitro. Notably, we effectively expressed mRNA-encoded protein and used the mRNA-LNP platform to generate A38-mRNA-LNP. Pharmacokinetic experiments were conducted in vivo and set up in two groups of mRNA-A38 group and A38 protein group, which were derived from mRNA-LNP and plasmid DNA-expressed proteins, respectively. A38-mRNA-LNPs were administrated by intramuscular injection, A38 proteins were administrated by intravenous administration, and their unique ability to maintain long-lasting protein concentrations by mRNA-encoded protein was demonstrated with the mRNA-encoded protein providing a longer circulating half-life compared to injection of the free A38 protein. These preclinical data on the mRNA-encoded antibody highlighted its potential to prevent infectious diseases in the future.


Assuntos
Doenças Transmissíveis , Lipossomos , Nanopartículas , Febre do Vale de Rift , Vírus da Febre do Vale do Rift , Animais , Humanos , Vírus da Febre do Vale do Rift/genética , Febre do Vale de Rift/prevenção & controle , Pandemias , Anticorpos Antivirais
4.
Artigo em Inglês | MEDLINE | ID: mdl-36875964

RESUMO

Most transradial prosthesis users with conventional "Sequential" myoelectric control have two electrode sites which control one degree of freedom (DoF) at a time. Rapid EMG co-activation toggles control between DoFs (e.g., hand and wrist), providing limited function. We implemented a regression-based EMG control method which achieved simultaneous and proportional control of two DoFs in a virtual task. We automated electrode site selection using a short-duration (90 s) calibration period, without force feedback. Backward stepwise selection located the best electrodes for either six or 12 electrodes (selected from a pool of 16). We additionally studied two, 2-DoF controllers: "Intuitive" control (hand open-close and wrist pronation-supination controlled virtual target size and rotation, respectively) and "Mapping" control (wrist flexion-extension and ulnar-radial deviation controlled virtual target left-right and up-down movement, respectively). In practice, a Mapping controller would be mapped to control prosthesis hand open-close and wrist pronation-supination. Eleven able-bodied subjects and 4 limb-absent subjects completed virtual target matching tasks (fixed target moves to a new location after being "matched," and subject immediately pursues) and fixed (static) target tasks. For all subjects, both 2-DoF controllers with 6 optimally-sited electrodes had statistically better target matching performance than Sequential control in number of matches (average of 4-7 vs. 2 matches, p< 0.001) and throughput (average of 0.75-1.25 vs. 0.4 bits/s, p< 0.001), but not overshoot rate and path efficiency. There were no statistical differences between 6 and 12 optimally-sited electrodes for both 2-DoF controllers. These results support the feasibility of 2-DoF simultaneous, proportional myoelectric control.

5.
J Electromyogr Kinesiol ; 69: 102753, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36731399

RESUMO

Bilateral movement is widely used for calibration of myoelectric prosthesis controllers, and is also relevant as rehabilitation therapy for patients with motor impairment and for athletic training. Target tracking and/or force matching tasks can be used to elicit such bilateral movement. Limited descriptive accuracy data exist in able-bodied subjects for bilateral target tracking or dominant vs non-dominant dynamic force matching tasks requiring more than one degree of freedom (DoF). We examined dynamic trajectory (0.75 Hz band-limited, white, uniform random) constant-posture, hand open-close, wrist pronation-supination target tracking and matching tasks. Tasks were normalized to maximum voluntary contraction (MVC), spanning a ± 30% MVC force range, in four 1-DoF and 2-DoF tasks: (1, 2) unilateral dominant limb tracking with/without visual feedback, and (3, 4) bilateral dominant/non-dominant limb tracking with mirror visual feedback. In 12 able-bodied subjects, unilateral tracking error with visual feedback averaged 10-15 %MVC, but up to 30 %MVC without visual feedback. Bilateral matching error averaged âˆ¼10 %MVC and was affected little by visual feedback type, so long as feedback was provided. In 1-DoF bilateral tracking, the dominant side had statistically lower error than the non-dominant side. In 2-DoF bilateral tracking, the side providing mirror visual feedback exhibited lower error than the opposite side. In 2-DoF tasks (assumed to be more challenging than their constituent 1-DoF tracking tasks), hand grip force errors grew disproportionately larger than those of each wrist DoF. In unilateral 1-DoF tasks, both hand vs target and wrist vs target latency averaged 250-350 ms. In unilateral 2-DoF tasks, wrist vs target latency also averaged 250-350 ms, while hand vs target latency averaged > 500 ms. These results provide guidance on bilateral 2-DoF hand-wrist performance in target tracking, and dominant vs non-dominant force matching tasks.


Assuntos
Força da Mão , Punho , Humanos , Punho/fisiologia , Força da Mão/fisiologia , Músculo Esquelético/fisiologia , Extremidade Superior , Mãos/fisiologia
6.
Ann Hematol ; 102(3): 621-628, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36633638

RESUMO

Renal impairment (RI) used to exclude multiple myeloma (MM) patients from autologous stem cell transplantation (ASCT) for safety concerns. Here, we retrospectively reviewed 34 consecutively transplanted patients with creatinine clearance < 60 ml/min at ASCT in recent 5 years at our institution. Busulfan/cyclophosphamide and high-dose melphalan were both employed as conditioning regimens. We found 62% grade 1-2 oral mucositis, 12% grade 3 oral mucositis, 48% grade 3 infection, 8% grade ≥ 4 infection, 50% grade 1 transient creatinine increase, 15% cardiac adverse events, and 12% engraftment syndrome. One case of secondary platelet graft failure and 1 case of transplantation-related mortality were observed. Interleukin-6 concentration was elevated among patients with increased body temperature and/or N-terminal pro-brain natriuretic peptide during engraftment, and close monitoring of these markers may help to predict susceptibility to cardiac events and engraftment syndrome. Adverse events occurred frequently, but the majority were manageable in this cohort. ASCT would further deepen the anti-myeloma efficacy and slightly ameliorated renal function. With a median follow-up of 26.2 months post transplantation (range: 1.6-74.8 months), the median progression-free survival (PFS) and overall survival (OS) post-transplantation of patients undergoing first-line transplantation were not reached; the median PFS post-transplantation of patients undergoing rescue transplantation was 19.2 months and the median OS was not reached.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Estomatite , Humanos , Estudos Retrospectivos , Creatinina , Transplante Autólogo , Melfalan , Condicionamento Pré-Transplante , Transplante de Células-Tronco
7.
Front Cell Infect Microbiol ; 12: 865170, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651756

RESUMO

Background: Haploidentical donor hematopoietic cell transplantation (haplo-HCT) has become a preferred option for patients without HLA-matched donors, but it increases the risk of viral reactivations. Epstein-Barr virus (EBV) and cytomegalovirus (CMV) are common viruses post-HCT, but limited data have been reported in the setting of haplo-HCT. Methods: We conducted a retrospective study enrolling acute leukemia patients who received haplo-HCT with myeloablative conditioning regimen employing ATG in our center from July 2014 to July 2017. All the patients enrolled were EBV-IgM and EBV-DNA negative but EBV-IgG positive, and so were their donors. The same went for CMV as well. Results: In total, 602 patients were recruited consisting of 331 with acute myeloid leukemia (AML) and 271 with acute lymphoblastic leukemia (ALL). One-year cumulative incidences of EBV (22.9% ± 2.4% vs. 27.4% ± 2.8%, P = 0.169) and CMV (24.7% ± 2.4% vs. 29.4% ± 2.8%, P = 0.190) reactivation were comparable between AML and ALL. EBV and CMV were independent risk factors for each other. In the AML group, male recipients [HR = 1.275, 95% CI (1.001-1.624), P = 0.049] and acute graft-versus-host disease [HR = 1.592, 95% CI (1.001-2.533), P = 0.049] were independent risk factors for EBV reactivation and CMV reactivation, respectively. CMV rather than EBV reactivation was related to a trend of worsened treatment-related mortality (TRM) (15.6% ± 0.1% vs. 10.2% ± 0.0%, P = 0.067) and progression-free survival (PFS) (60.6% ± 4.1% vs. 70.3% ± 2.3%, P = 0.073), while significant impacts were revealed only in the subgroup analysis. CMV reactivation resulted in a remarkable inferior 2-year overall survival (OS) (64.2% ± 5.7% vs. 77.6% ± 3.2%, P = 0.038) and PFS (55.0% ± 5.9% vs. 71.9% ± 3.4%, P = 0.042) in ALL patients. On the other hand, in the EBV+/CMV- subgroup, relapse was lower in ALL patients (8.2% ± 0.2% vs. 32.4% ± 0.8%, P = 0.010) compared with AML patients, which led to a superior 2-year OS (82.0% ± 6.2% vs. 60.3% ± 8.8%, P = 0.016) and PFS (74.5% ± 7.0% vs. 57.5% ± 8.4%, P = 0.036). Conclusion: We concluded that EBV and CMV reactivations were frequent in acute leukemia patients after haplo-HCT, with possibly distinctive risk factors from HLA-matched HCT. There could be a potential interaction between EBV and CMV, but impacts on transplant outcomes remained complex.


Assuntos
Infecções por Citomegalovirus , Infecções por Vírus Epstein-Barr , Leucemia Mieloide Aguda , Citomegalovirus , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4 , Humanos , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/terapia , Masculino , Estudos Retrospectivos , Ativação Viral/fisiologia
8.
Leuk Lymphoma ; 63(11): 2636-2644, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35731036

RESUMO

Leukapheresis is an effective adjuvant therapy for leukemia patients with hyperleukocytosis, but few studies have reported recent data with modern modalities and comparisons among different leukemia types. We conducted a retrospective study on leukapheresis among 420 patients with AML, ALL and CML in four local centers. WBC counts decreased significantly (p < 0.001) postleukapheresis in all three cohorts. Clearance efficiency was higher in acute leukemia patients than CML patients (p < 0.01). Concomitant leukocytoreduction drugs improved WBC reduction only in AML patients (p < 0.05). Leukocyte, hemoglobin and platelet levels preleukapheresis might affect the clearance efficiency in AML and/or ALL patients. Hematological toxicities were the major concerns, but most of them were mild, and only 11 patients died of all causes within one week postleukapheresis. In conclusion, leukapheresis can safely reduce the leukemic burden, especially for patients with acute leukemias.


Assuntos
Leucaférese , Leucemia Mieloide Aguda , Humanos , Estudos Retrospectivos , Leucocitose/terapia , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/complicações , Contagem de Leucócitos , Doença Aguda
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(2): 361-366, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35395964

RESUMO

OBJECTIVE: To analyze and compare the effects of leukapheresis on hemostatic function in patients with hyperleukocytic leukemia. METHODS: A total of 139 patients with AML, ALL and CML who underwent leukapheresis from June 2009 to February 2020 and did coagulation test before and after operation were included in this study. The clearance efficiency of each group and the difference among three groups were evaluated, as well as hemostatic function including platelet counts, coagulation indicators, CDSS score and incidence of adverse events. The difference of hemostatic function caused by leukapheresis in different leukemia patients were compared. RESULTS: After leukapheresis, the WBC counts were decreased significantly in the three groups of patients (P<0.001), and the clearance efficiency was highest in ALL patients. However, the platelet counts also were decreased significantly (AML:P<0.001, ALL: P<0.001, CML: P<0.01) in the three groups of patients, particularly for acute leukemia patients with a positive correlation with WBC clearance efficiency(r=0.284). After leukapheresis, fibrinogen decreased, PT and APTT prolonged. For acute leukemia patients, higher CDSS score was related to an elevated incidence of bleeding events (P<0.05). CONCLUSION: Leukapheresis is an effective method to decrease the leukemic burden, but it is necessary to monitor the impact on hemostatic function. It is recommended to assess the CDSS socre for acute leukemia patients, in order to identify the predictive value for bleedings.


Assuntos
Hemostáticos , Leucemia Mieloide Aguda , Doença Aguda , Coagulação Sanguínea , Testes de Coagulação Sanguínea , Hemorragia , Humanos , Leucaférese/métodos , Leucemia Mieloide Aguda/terapia
10.
Artigo em Inglês | MEDLINE | ID: mdl-35349446

RESUMO

Recent research has advanced two degree-of-freedom (DoF), simultaneous, independent and proportional control of hand-wrist prostheses using surface electromyogram signals from remnant muscles as the control input. We evaluated two such regression-based controllers, along with conventional, sequential two-site control with co-contraction mode switching (SeqCon), in box-block, refined-clothespin and door-knob tasks, on 10 able-bodied and 4 limb-absent subjects. Subjects operated a commercial hand and wrist using a socket bypass harness. One 2-DoF controller (DirCon) related the intuitive hand actions of open-close and pronation-supination to the associated prosthesis hand-wrist actions, respectively. The other (MapCon) mapped myoelectrically more distinct, but less intuitive, actions of wrist flexion-extension and ulnar-radial deviation. Each 2-DoF controller was calibrated from separate 90 s calibration contractions. SeqCon performed better statistically than MapCon in the predominantly 1-DoF box-block task (>20 blocks/minute vs. 8-18 blocks/minute, on average). In this task, SeqCon likely benefited from an ability to easily focus on 1-DoF and not inadvertently trigger co-contraction for mode switching. The remaining two tasks require 2-DoFs, and both 2-DoF controllers each performed better (factor of 2-4) than SeqCon. We also compared the use of 12 vs. 6 optimally-selected EMG electrodes as inputs, finding no statistical difference. Overall, we provide further evidence of the benefits of regression-based EMG prosthesis control of 2-DoFs in the hand-wrist.


Assuntos
Membros Artificiais , Punho , Eletromiografia , Mãos/fisiologia , Humanos , Músculo Esquelético/fisiologia , Punho/fisiologia , Articulação do Punho/fisiologia
11.
Platelets ; 33(8): 1132-1138, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-35348422

RESUMO

Triggering receptor expressed on myeloid cells (TREM) like transcript-1 (TLT-1) is a membrane protein receptor found in α-granules of megakaryocytes and platelets. Upon platelet activation TLT-1 is rapidly relocated to the surface of platelets. In plasma, a soluble form of TLT-1 (sTLT-1) is present. Plasma levels of sTLT-1 are significantly elevated in thrombotic diseases. In the present study, we investigated to whether TLT-1 reflects platelet activation in pregnant women with preeclampsia. We studied 30 preeclamptic patients who were matched with 30 normotensive pregnant women and 30 non-pregnant controls. Basal TLT-1, P-selectin, and CD63 expressions on platelets were analyzed with the use of flow-cytometry (FCM). Platelet reactivity was induced by thrombin receptor activation peptide and determined by FCM. Plasma concentrations of sTLT-1 and soluble P-selectin (sP-selectin) were measured by an enzyme-linked immunosorbent assay. Results show that basal platelet expression of TLT-1, P-selectin and CD63 were increased in women with preeclampsia (PE) compared with normotensive pregnant women (NP). Platelets from PE women and NP women were more responsive compared to from nonpregnant women controls (NC), and which was demonstrated by increased expression of TLT-1, P-selectin, and CD63 upon stimulation in vitro. Plasma concentration of sTLT-1 was greater in PE women compared to NP women and NC women. Plasma sP-selectin level was higher in pregnant women than in nonpregnant women, but there were no significant differences between PE and NP women. In summary, our results revealed that platelet activation is prominent in preeclampsia, TLT-1 reflects platelet activation and may be a useful indicator for preeclampsia.


Assuntos
Selectina-P , Pré-Eclâmpsia , Plaquetas/metabolismo , Feminino , Humanos , Células Mieloides/metabolismo , Selectina-P/metabolismo , Peptídeos , Ativação Plaquetária , Gravidez , Receptores Imunológicos , Receptores de Trombina/metabolismo
12.
Sensors (Basel) ; 21(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34372403

RESUMO

To facilitate the broader use of EMG signal whitening, we studied four whitening procedures of various complexities, as well as the roles of sampling rate and noise correction. We separately analyzed force-varying and constant-force contractions from 64 subjects who completed constant-posture tasks about the elbow over a range of forces from 0% to 50% maximum voluntary contraction (MVC). From the constant-force tasks, we found that noise correction via the root difference of squares (RDS) method consistently reduced EMG recording noise, often by a factor of 5-10. All other primary results were from the force-varying contractions. Sampling at 4096 Hz provided small and statistically significant improvements over sampling at 2048 Hz (~3%), which, in turn, provided small improvements over sampling at 1024 Hz (~4%). In comparing equivalent processing variants at a sampling rate of 4096 Hz, whitening filters calibrated to the EMG spectrum of each subject generally performed best (4.74% MVC EMG-force error), followed by one universal whitening filter for all subjects (4.83% MVC error), followed by a high-pass filter whitening method (4.89% MVC error) and then a first difference whitening filter (4.91% MVC error)-but none of these statistically differed. Each did significantly improve from EMG-force error without whitening (5.55% MVC). The first difference is an excellent whitening option over this range of contraction forces since no calibration or algorithm decisions are required.


Assuntos
Articulação do Cotovelo , Cotovelo , Algoritmos , Eletromiografia , Humanos , Contração Isométrica , Contração Muscular , Músculo Esquelético , Postura
13.
BMC Pregnancy Childbirth ; 20(1): 774, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33308174

RESUMO

BACKGROUND: The fetal adrenal gland is a highly vascularized organs and develops two recognizable distinct zones in uetro, inner fetal zone (FZ) and outer definitive zone (DZ). Based on the region supplied, middle adrenal artery (MAA) mainly contribute to FZ while inferior adrenal artery (IAA) mainly to the inferior part of DZ. The purpose of this study was to establish reference ranges of adrenal artery Doppler indices of IAA and MAA, and assess zonal difference of blood supply to fetal adrenal gland. METHODS: The pulsatility index (PI), resistance index (RI), and systolic:diastolic ratio (S/D) of the IAA and MAA were obtained serially at 4-week intervals in normal fetuses. The MAA and IAA were referred based on the course and location in the gland: IAA referring the artery that mainly branches from the renal artery and walks along the renal upper pole, distributing the inferoposterior part of DZ in the adrenal gland while MAA as arterial blood flowing along the single central adrenal vein in the medial part of the gland. Multilevel modeling was performed to establish the gestational age-associated reference ranges for IAA and MAA. Differences in Doppler indices between the IAA and MAA were assessed. RESULTS: One hundred sixty-eight fetuses with 843 observations were included. The IAA had a higher detection rate than the MAA (100% vs 89.2%, p < 0.05). The resistance of IAA had a reduction around 35 weeks of gestation and that of MAA remained unchanged throughout the second half of pregnancy. Lower PI, RI and S/D were observed in the MAA than in the IAA (p < 0.05) from 752 paired measurements. CONCLUSION: There is a zonal difference in blood supply in favor of the fetal zone, which may correspond to its unique function. Reference ranges of Doppler parameters in adrenal artery maybe beneficial for further evaluation of fetal hemodynamics.


Assuntos
Glândulas Suprarrenais/irrigação sanguínea , Fluxo Pulsátil/fisiologia , Artérias Umbilicais/diagnóstico por imagem , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/embriologia , Adulto , Feminino , Humanos , Estudos Longitudinais , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/embriologia , Gravidez , Valores de Referência , Ultrassonografia Doppler em Cores , Ultrassonografia Pré-Natal , Artérias Umbilicais/embriologia
14.
IEEE Trans Neural Syst Rehabil Eng ; 28(12): 3040-3050, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33196443

RESUMO

System identification models relating forearm electromyogram (EMG) signals to phantom wrist radial-ulnar deviation force, pronation-supination moment and/or hand open-close force (EMG-force) are hampered by lack of supervised force/moment output signals in limb-absent subjects. In 12 able-bodied and 7 unilateral transradial limb-absent subjects, we studied three alternative supervised output sources in one degree of freedom (DoF) and 2-DoF target tracking tasks: (1) bilateral tracking with force feedback from the contralateral side (non-dominant for able-bodied/ sound for limb-absent subjects) with the contralateral force as the output, (2) bilateral tracking with force feedback from the contralateral side with the target as the output, and (3) dominant/limb-absent side unilateral target tracking without feedback and the target used as the output. "Best-case" EMG-force errors averaged ~ 10% of maximum voluntary contraction (MVC) when able-bodied subjects' dominant limb produced unilateral force/moment with feedback. When either bilateral tracking source was used as the model output, statistically larger errors of 12-16 %MVC resulted. The no-feedback alternative produced errors of 25-30 %MVC, which was nearly half the tested force range of ± 30 %MVC. Therefore, the no-feedback model output was not acceptable. We found little performance variation between DoFs. Many subjects struggled to perform 2-DoF target tracking.


Assuntos
Articulação do Punho , Punho , Eletromiografia , Antebraço , Mãos , Humanos , Músculo Esquelético
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 369-373, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018005

RESUMO

Single-use EMG-force models (i.e., a new model is trained each time the electrodes are donned) are used in various areas, including ergonomics assessment, clinical biomechanics, and motor control research. For one degree of freedom (1-DoF) tasks, input-output (black box) models are common. Recently, black box models have expanded to 2-DoF tasks. To facilitate efficient training, we examined parameters of black box model training methods in 2-DoF force-varying, constant-posture tasks consisting of hand open-close combined with one wrist DoF. We found that approximately 40-60 s of training data is best, with progressively higher EMG-force errors occurring for progressively shorter training durations. Surprisingly, 2-DoF models in which the dynamics were universal across all subjects (only channel gain was trained to each subject) generally performed 15-21% better than models in which the complete dynamics were trained to each subject. In summary, lower error EMG-force models can be formed through diligent attention to optimization of these factors.


Assuntos
Mãos , Punho , Eletromiografia , Postura , Articulação do Punho
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3122-3125, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018666

RESUMO

Previous works have shown that whitening improves the processed electromyogram (EMG) signal for use in end applications such as EMG to torque modelling. Traditional whitening methods fit each subject from calibration contractions, which is a hindrance to their widespread use. To eliminate this cumbersome calibration, a universal whitening filter was developed using the whitening filters from a pre-existing data set (64 subjects, 8 electrodes/subject). Since the shape of each subject-specific whitening filter was observed to be relatively consistent across subjects, the universal whitening filter was formed as their ensemble average. The processed EMG was then used to model surface EMG to torque about the elbow. Traditional and universal whitening provided the same EMG-torque benefit, each improving statistically over unwhitened processing by ~14% during dynamic contractions. We further studied the use of root difference of squares (RDS) post-processing to attenuate additive measurement noise in EMG channels. With and without whitening, RDS processing (vs. no RDS processing) better attenuated additive noise, reducing it from 2-4% (on average) of the processed EMG from a 50% contraction down to < 1%. The combined use of universal whitening filters and RDS processing should be a particular benefit in real-time applications such as prosthesis control.


Assuntos
Articulação do Cotovelo , Processamento de Sinais Assistido por Computador , Cotovelo , Eletromiografia , Humanos , Torque
17.
J Clin Endocrinol Metab ; 105(12)2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32946562

RESUMO

OBJECTIVE: To characterize the inferior adrenal artery (IAA) pulsatility index (PI) in intrauterine growth-restricted (IUGR) fetuses without brain sparing. METHODS: Twenty-three IUGR fetuses with a normal Doppler cerebroplacental ratio (CPR) and 23 normal controls were included in this prospective cross-sectional study. The PI of the IAA was recorded using routine transabdominal Doppler ultrasound. The differences in Doppler characteristics, perinatal outcomes, and steroidogenesis in the umbilical vein at birth (adrenocorticotropic hormone [ACTH] and cortisol [F] levels) were compared between the 2 groups. The correlations between IAA-PI and steroidogenesis were assessed in the IUGR group. RESULTS: IAA-PI was significantly lower in IUGR fetuses than in normal controls (0.85 vs 1.18 at first scan, 0.78 vs 0.92 at last scan; both P < 0.001). The plasma F and ACTH levels in IUGR cases were significantly higher than those of the normal controls (18.2 vs 12.4 µg/dL and 280.5 vs 125.6 pg/mL for F and ACTH, respectively; both P < 0.001). There were negative correlations between IAA-PI and plasma F values and between IAA-PI and ACTH values in the IUGR group (r = -0.774 and -0.82 at first scan, r = -0.525 and -0.45 at last scan, respectively; P < 0.001). CONCLUSION: Increased adrenal gland blood flow with concomitant increases in ACTH and F levels were observed in IUGR fetuses. IAA-PI is useful to assess early blood redistribution and may be beneficial for evaluating the steroidogenic response in high-risk pregnancies.


Assuntos
Corticosteroides/biossíntese , Glândulas Suprarrenais/irrigação sanguínea , Artérias/fisiologia , Retardo do Crescimento Fetal , Feto/irrigação sanguínea , Veias Umbilicais/metabolismo , Adolescente , Corticosteroides/sangue , Hormônio Adrenocorticotrópico/biossíntese , Hormônio Adrenocorticotrópico/sangue , Adulto , Artérias/diagnóstico por imagem , Circulação Sanguínea/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Estudos de Casos e Controles , China , Estudos Transversais , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/metabolismo , Retardo do Crescimento Fetal/fisiopatologia , Feto/diagnóstico por imagem , Feto/metabolismo , Indicadores Básicos de Saúde , Humanos , Hidrocortisona/biossíntese , Hidrocortisona/sangue , Recém-Nascido , Masculino , Gravidez , Fluxo Pulsátil , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Veias Umbilicais/diagnóstico por imagem , Adulto Jovem
18.
Bone Marrow Transplant ; 55(9): 1754-1762, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32066862

RESUMO

Epstein-Barr virus (EBV) reactivation after allogeneic hematopoietic cell transplantation (allo-HCT) is one of the major concerns that may lead to fatal EBV diseases. However, updated data are needed because of the remarkable evolution of the HCT protocol and donor selection. We conducted a retrospective study that enrolled 890 allo-HCT recipients. Independent risk factors for EBV reactivation were use of antithymocyte globulin, haploidentical donor, and the presence of chronic graft-versus-host disease. The cumulative incidence of EBV reactivation was 2.9%, 11.7%, 27.3%, and 41.9% for patients with 0, 1, 2, and 3 risk factors, respectively (P < 0.001). Posttransplant lymphoproliferative disorders (PTLDs) occurred in seven patients. EBV reactivation was associated with inferior survival in recipients who survived more than 2 years post-HCT (P < 0.001) but might time-dependently benefit those patients with malignancies by decreasing relapse incidence (P = 0.046). A decreased relapse incidence was observed 1 year after HCT for recipients at first or second remission (P = 0.042) and in the first year post-HCT for recipients with advanced diseases (P = 0.032). We concluded that with current management, PTLDs were efficiently controlled, but EBV reactivation still had a multifactorial impact on transplant outcomes. Multicenter prospective studies are warranted to validate these findings.


Assuntos
Infecções por Vírus Epstein-Barr , Transplante de Células-Tronco Hematopoéticas , Transtornos Linfoproliferativos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 4 , Humanos , Estudos Prospectivos , Estudos Retrospectivos
19.
IEEE Trans Neural Syst Rehabil Eng ; 27(12): 2328-2335, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31689197

RESUMO

Typical electromyogram (EMG) processors estimate EMG signal standard deviation (EMG σ ) via moving average root mean square (RMS) or mean absolute value (MAV) filters, whose outputs are used in force estimation, prosthesis/orthosis control, etc. In the inevitable presence of additive measurement noise, some processors subtract the noise standard deviation from EMG RMS (or MAV). Others compute a root difference of squares (RDS)-subtract the noise variance from the square of EMG RMS (or MAV), all followed by taking the square root. Herein, we model EMG as an amplitude-modulated random process in additive measurement noise. Assuming a Gaussian (or, separately, Laplacian) distribution, we derive analytically that the maximum likelihood estimate of EMG σ requires RDS processing. Whenever that subtraction would provide a negative-valued result, we show that EMG σ should be set to zero. Our theoretical models further show that during rest, approximately 50% of EMG σ estimates are non-zero. This result is problematic when EMG σ is used for real-time control, explaining the common use of additional thresholding. We tested our model results experimentally using biceps and triceps EMG from 64 subjects. Experimental results closely followed the Gaussian model. We conclude that EMG processors should use RDS processing and not noise standard deviation subtraction.


Assuntos
Algoritmos , Eletromiografia/estatística & dados numéricos , Eletromiografia/métodos , Músculos Isquiossurais/fisiologia , Humanos , Funções Verossimilhança , Modelos Teóricos , Contração Muscular , Distribuição Normal , Próteses e Implantes , Padrões de Referência , Processamento de Sinais Assistido por Computador
20.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 48(3): 318-325, 2019 05 25.
Artigo em Chinês | MEDLINE | ID: mdl-31496165

RESUMO

Proteins are the physical basis of life and perform all kinds of life activities. Proteins have different orientations and function in different tissues. The same protein, located in different subcellular regions, can perform different and even opposite functions. Both functional and structural proteins are capable of undergoing re-localization which can directly or indirectly participate in signal transduction. Due to abnormal transduction of signals during carcinogenesis, the proteins originally expressed in the cytoplasm are translocated into the nucleus and lead to functional changes in the tumor tissue. The changes of protein localization are affected by many factors, including the interaction between proteins, expression level of proteins and the cleaved intracellular domain of transmembrane protein.


Assuntos
Núcleo Celular , Citoplasma , Proteínas de Membrana , Carcinogênese/patologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Membrana/metabolismo , Domínios Proteicos , Transporte Proteico/fisiologia , Transdução de Sinais
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