Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “multimodality”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17Linked to original sources

Multimodal contribution to speech perception revealed by independent component analysis: a single-sweep EEG case study.

In this single-sweep electroencephalographic case study, independent component analysis (ICA) was used to investigate multimodal processes underlying the enhancement of speech intelligibility in noise (for monosyllabic English words) by visualizing facial motion concordant with the audio speech signal. Wavelet analysis of the single-sweep IC activation waveforms revealed increased high-frequency energy for two ICs underlying the visual enhancement effect. For one IC, current source density analysis localized activity mainly to the superior temporal gyrus, consistent with principles of multimodal integration. For the other IC, activity was distributed across multiple cortical areas perhaps reflecting global mappings underlying the visual enhancement effect.

Adult↗

Multimodality in the superior colliculus: an information theoretic analysis.

The deep superior colliculus (DSC) integrates multisensory input and triggers an orienting movement toward the source of stimulation (target). It would seem reasonable to suppose that input of an additional modality should always increase the amount of information received by a DSC neuron concerning a target. However, of all DSC neurons studied, only about one half in the cat and one-quarter in the monkey were multimodal. The rest received only unimodal input. Multimodal DSC neurons show the properties of multisensory enhancement, in which the neural response to an input of one modality is augmented by input of another modality, and of inverse effectiveness, in which weaker unimodal responses produce a higher percentage enhancement. Previously, we demonstrated that these properties are consistent with the hypothesis that DSC neurons use Bayes' rule to compute the posterior probability that a target is present given their stochastic sensory inputs. Here we use an information theoretic analysis of our Bayesian model to show that input of an additional modality may indeed increase target information, but only if input received from the initial modality does not completely reduce uncertainty concerning the presence of a target. Unimodal DSC neurons may be those whose unimodal input fully reduces target uncertainty and therefore have no need for input of another modality.

Bayes Theorem↗

Multimodality treatment resulting in long-term survival in hepatocellular carcinoma.

The early detection and complex therapy of the hepatocellular carcinoma (HCC) is one of the most seasonable questions of the gastroenterology-oncology, because of the increasing prevalence of the primary liver cancer. The course of the hepatocellular carcinoma is rapid, untreated patients rarely live over 5-6 months. Combination of different treatment modalities in HCC can offer the best chances for survival. If possible, a surgical resection should be the primary procedure, followed by adjuvant cytostatic treatment and chemoembolisation. The authors report three cases with HCC with extremely long survival. The long-term survival achieved by multimodality therapy, as presented in these cases, seems to justify aggressive therapeutical approaches in HCC. It has been concluded, that early detection and complex, aggressive multimodality treatment--even repeated liver resections and surgical elimination of duplex distant metastases--can result in long-term survival with a good quality of life.

Aged↗

Vascular thoracic outlet syndrome: successful outcomes with multimodal therapy.

PURPOSE: Vascular thoracic outlet syndrome (TOS) can present with signs of arterial impingement or, more commonly, as venous obstruction. In an effort to decrease morbidity associated with vascular thoracic outlet syndrome, we have used an aggressive multimodal treatment approach. METHODS: Since November 1992, we have evaluated 29 patients with vascular thoracic outlet syndrome. Nine of ten patients with arterial thoracic outlet syndrome had first rib resections. Eighteen of 19 patients with venous occlusion underwent anticoagulation, thrombolysis, and first rib resection. Eight patients required additional endovascular therapy for persistent stenoses, either venous angioplasty alone (2) or angioplasty plus stent placement (6). RESULTS: Follow up extends to 75months with a mean of 24months. Patients with stents have been followed for a mean of 38months. Twenty-five of 28 patients managed with multimodal therapy were essentially asymptomatic at last follow up. CONCLUSION: Thrombolysis, anticoagulation, surgical decompression, and endovascular procedures act synergistically to improve results of therapy in patients with vascular thoracic outlet syndrome.

Adult↗

Multimodal evoked potentials in myotonic dystrophy (MyD).

By means of multimodal evoked potentials (EPs), we evaluated the central nervous system (CNS) involvement in 25 subjects suffering from myotonic dystrophy: brainstem auditory evoked potentials (BAEPs), middle-latency auditory evoked potentials (MLAEPs) and somatosensory evoked potentials (SEPs) from the upper limb were performed on all subjects, whereas only the 19 patients, whose clinical ocular abnormalities were slight, underwent pattern-electretinograms (PERGs) and pattern visual-evoked potentials (VEPs) in order to identify the site of lesion among visual pathways (retinal and/or retroretinal). PERGs were abnormal in 8/19 subjects, VEPs in 8/19 subjects (the two techniques were simultaneously abnormal in 8 eyes), BAEPs in 7/25 subjects, MLAEPs in 4/25 subjects (in one subject both BAEps and MLAEPs were abnormal) and SEPs were abnormal in 1/25 subjects. 13/25 of our subjects showed at least one EP that revealed a CNS involvement. The electrophysiological alterations were not correlated either with subject age or with disease duration. Multimodal EPs enabled us to demonstrate that CNS involvement in myotonic dystrophy is important and mainly affects the visual and auditory system.

Adult↗

Automatic change detection in multimodal serial MRI: application to multiple sclerosis lesion evolution.

The automatic analysis of subtle changes between MRI scans is an important tool for assessing disease evolution over time. Manual labeling of evolutions in 3D data sets is tedious and error prone. Automatic change detection, however, remains a challenging image processing problem. A variety of MRI artifacts introduce a wide range of unrepresentative changes between images, making standard change detection methods unreliable. In this study we describe an automatic image processing system that addresses these issues. Registration errors and undesired anatomical deformations are compensated using a versatile multiresolution deformable image matching method that preserves significant changes at a given scale. A nonlinear intensity normalization method is associated with statistical hypothesis test methods to provide reliable change detection. Multimodal data is optionally exploited to reduce the false detection rate. The performance of the system was evaluated on a large database of 3D multimodal, MR images of patients suffering from relapsing remitting multiple sclerosis (MS). The method was assessed using receiver operating characteristics (ROC) analysis, and validated in a protocol involving two neurologists. The automatic system outperforms the human expert, detecting many lesion evolutions that are missed by the expert, including small, subtle changes.

Algorithms↗

Intraoperative radiotherapy in the multimodality approach to gastric cancer.

It is difficult to conclude a clear benefit from the addition of IORT to the multimodality treatment of gastric cancer based on the studies available. Only three prospective randomized trials have been published and each varies in the approach of combining adjuvant and neoadjuvant chemotherapy and EBRT with IORT. With a complex degree of confounding factors in these and other retrospective series, it also remains difficult to identify a decrease in local recurrence rates, or an improvement in overall patient survival rates attributable to the use of IORT. Several series, however, have identified patient subsets--specifically, patients who have advanced disease with serosal extension or node-positive disease--who may be more likely to benefit from the addition of IORT to gastric resection. Finally, there is no evidence in prospective or retrospective series that there is an increased patient risk or inferior outcome caused by the addition of IORT. Limited evidence of a possible benefit in advanced disease and no evidence of a disadvantage to the use of IORT have promoted continued use and investigation in the multimodality treatment of an aggressive disease. Continued efforts in prospective randomized trials should be promoted to further delineate the efficacy of IORT and EBRT in the treatment of gastric cancer, especially in light of recently published data [30], where concurrent chemotherapy has been reported to increase survival rates in high-risk patients.

Adenocarcinoma↗

Voxelwise mapping of magnetic resonance ventilation-perfusion ratio in a porcine model by multimodality registration: technical note.

RATIONALE AND OBJECTIVES: The purpose of this study was to demonstrate the construction of voxelwise ventilation-perfusion (V/Q) ratio maps in a porcine model by nonrigidly aligning the respective ventilation and perfusion images using a multimodality registration algorithm. MATERIALS AND METHODS: The first-pass contrast agent technique for a blood flow map and 3He used for ventilation imaging were performed using a normal porcine model. The registered 3He-ventilation image was then aligned to the blood flow map using a multimodality registration algorithm. The voxelwise V/Q ratios were calculated by dividing the registered 3He-ventilation image by the blood flow map. The V/Q ratios were also semi-logarithmically scatter-plotted against the number of voxels. RESULTS: From perfusion magnetic resonance images, a voxel-by-voxel blood flow map was produced. Registered 3He ventilation image was successfully obtained as well as V/Q ratio map. Plots of the V/Q ratios obtained by this registration approach were similar to the logarithmic normal distribution. CONCLUSION: Registration of MR perfusion and ventilation images can potentially enable quantitative evaluation of regional pulmonary function and thus yield deeper insight into the physiology and pathophysiology of the lung.

Animals↗

BaSO4-loaded agarose: a construction material for multimodality imaging phantoms.

RATIONALE AND OBJECTIVES: Phantom studies are an important part of the evaluation of imaging techniques; however, presently available phantom construction materials are not adequate for studies involving both magnetic resonance (MR) imaging and computed tomography (CT). The purpose of this study was to design a phantom construction material useful for multimodality imaging experiments. MATERIALS AND METHODS: Iodinated contrast agent or BaSO4 was added during the formation of agarose gels. Both CT and MR imaging were performed, and T1 and T2 values and CT numbers (in Hounsfield units) were obtained for multiple combinations of contrast material and agarose. Results. The T2 values of agarose gels span the range of those values found in biologic tissues. Phantoms containing iodinated contrast agent were not stable; contrast agent diffused across concentration gradients. BaSO4-loaded agarose phantoms were stable, however, and varying barium concentrations produced phantoms that spanned the range of CT numbers found in biologic tissues. Addition of BaSO4 did not substantially alter T1 or T2 values of agarose gels. Agarose concentration had only a small effect on the CT numbers of BaSO4 suspensions. CONCLUSION: BaSO4-loaded agarose is an effective material for construction of multimodality imaging phantoms. It provides adequate signal intensity for MR imaging and attenuation for CT, with independently variable contrast in both modalities.

Agar↗

Near-total esophagectomy: the influence of standardized multimodal management and intraoperative fluid restriction.

BACKGROUND AND OBJECTIVES: Esophagectomy can be associated with high morbidity and mortality. We present our experience managing these patients using a standardized multimodal approach that emphasizes intraoperative fluid restriction and early extubation. METHODS: This case series includes 56 consecutive patients over a 2-year period (1999-2000) that underwent near-total esophagectomy at a high-volume center. Surgical approach was determined by patient and tumor characteristics; intraoperative fluid replacement was conservative; and patient-controlled epidural anesthesia/analgesia was used to promote early extubation, enteral feeding, and ambulation. RESULTS: Overall morbidity was 18%; in-hospital and 30-day mortality was zero. Intraoperative urinary volume averaged 0.57 mL/kg/h. No patient developed postoperative renal dysfunction or pulmonary complications. All patients were extubated in the operating room. First ambulation averaged 1.6 days after surgery. Median intensive care unit and hospital stays were 1 and 10 days, respectively. Side effects from thoracic epidural analgesia were minimal. CONCLUSIONS: Significant reduction in esophagectomy-related morbidity is possible using a standardized multimodal approach in routine clinical practice. Intraoperative fluid restriction may facilitate early extubation and reduce pulmonary complications without compromising renal function. This preliminary observation warrants further study in a randomized clinical trial.

Adolescent↗

Does adding intravenous fentanyl to caudal block in children enhance the efficacy of multimodal analgesia as reflected in the plasma level of catecholamines?

BACKGROUND AND OBJECTIVE: Several studies showed that single analgesic modality management can attenuate perioperative stress, but little is known about the effect of multimodal analgesia on catecholamine responses to surgical trauma in children. METHODS: Fifty children (American Society of Anesthesiologists Grade I or II) were randomly allocated to one of two groups: one received general anaesthesia and a caudal block (control group), and one group was given general anaesthesia, caudal block and intravenous (i.v.) fentanyl 2 microg kg(-1) (fentanyl group). Plasma epinephrine and norepinephrine concentrations were measured three times during the perioperative period: at induction time (T(0)), at the end of surgery (T(1)) and when the children were fully awake in the postanaesthesia care unit (T(2)). RESULTS: There was a significant reduction in the catecholamine levels in the two groups when (T(1)) and (T(2)) were compared with T(0). When plasma epinephrine levels (at T(0), T(1) and T(2)) between the two groups were compared, a statistically significant reduction at T(2) was obtained in the fentanyl group, when compared with the control group. However, plasma norepinephrine levels showed no statistically significant difference between the two groups (at T(0), T(1) and T(2)). CONCLUSION: These findings suggest that the multimodal analgesic approach of adding i.v. low-dose fentanyl to a caudal block may decrease the plasma epinephrine release in children undergoing inguinal herniotomy.

Analgesia↗

Multimodal electrophysiological assessment of ataxia telangiectasia.

We report multimodal evoked response studies in eleven children with ataxia telangiectasia. The ABRs were normal in all but one patient despite the severity of the disorder. The SERs were abnormal in all of the patients, the waveforms being either absent or of delayed latency, the abnormalities were more marked in the older patients. Abnormal motor and sensory nerve conduction studies were also found in all but the younger few patients. Most notably, the VERs were abnormal in all but 2, the older patients had delayed VERs and most had small amplitude responses. The electrophysiological profile of ataxia telangiectasia patients on the multimodal evoked responses differs from that found in certain other degenerative ataxias studied and may have some diagnostic utility.

Adolescent↗

Multimodal assessment of the primary healthcare system of Serbia: a model for evaluating post-conflict health systems.

INTRODUCTION: Conflicts, social unrest, and disasters can significantly affect the ability of a healthcare system to provide for the needs of its citizens. The collapse of the primary healthcare system in Serbia is a model of the effects that civil unrest can have on the health of a population. However, with improving social and political conditions, focus now can be turned towards the greatly needed development and reorganization of the primary healthcare system in Serbia. Due to the complexity of health-system reform in the post-conflict/post-disaster setting, attempts to restructure health services are fraught with pitfalls that often are unanticipated because of inadequate preliminary assessments. A multimodal assessment involving quantitative and qualitative methodologies may provide a more robust mechanism to identify key programmatic priorities and critical barriers for appropriate and sustainable health-system interventions. The purpose of this study is to describe a multimodal assessment using primary healthcare in post-conflict Serbia as a model. METHODS: Integrated quantitative and qualitative methodologies--system characterization and observation, focus group discussions, free-response questionnaires, and Q-methodology--were used to identify needs, problems, and potential barriers to primary healthcare development in Serbia. Participants included primary healthcare providers and administrators from 13 institutions throughout Belgrade. RESULTS: Demographic data indicate a well-established infrastructure of primary health centers and stations. However, focus group discussions and free-response questionnaires reveal significant impediments to delivery of care: (1) Inadequate equipment, supplies, and medications; (2) Poor financial investment; (3) Discouraging worker salaries; (4) Few opportunities for professional development; and (5) Little emphasis on or respect for primary healthcare. Q-methodology of provider perceptions and opinions supports these concerns, shows remarkable consensus among participants, and provides further insights toward system development by grouping respondents into distinctive types. CONCLUSIONS: This study identified the critical needs and barriers to development of primary healthcare in Serbia. This combined methodology may serve as a model for future health system assessments in the post-conflict and post-disaster settings.

Delivery of Health Care↗

Use of analyte-modulated modal power distribution in multimode optical fibers for simultaneous single-wavelength evanescent-wave refractometry and spectrometry.

A new method is described for the simultaneous determination of absorbance and refractive index of a sample medium. The method is based on measurement of the analyte-modulated modal power distribution (MPD) in a multimode waveguide. In turn, the MPD is quantified by the far-field spatial pattern and intensity of light, i.e., the Fraunhofer diffraction pattern (registered on a CCD camera), that emerges from a multimode optical fiber. Operationally, light that is sent down the fiber interacts with the surrounding analyte-containing medium by means of the evanescent wave at the fiber boundary. The light flux in the propagating beam and the internal reflection angles within the fiber are both affected by optical absorption connected with the analyte and by the refractive index of the analyte-containing medium. In turn, these angles are reflected in the angular divergence of the beam as it leaves the fiber. As a result, the Fraunhofer diffraction pattern of that beam yields two parameters that can, together, be used to deduce refractive index and absorbance. This MPD based detection offers important advantages over traditional evanescent-wave detection strategies which rely on recording only the total transmitted optical power or its lost fraction. First, simultaneous determination of sample refractive index and absorbance is possible at a single probe wavelength. Second, the sensitivity of refractometric and absorption measurements can be controlled simply, either by adjusting the distance between the end face of the fiber and the CCD detector or by monitoring selected modal groups at the fiber output. As a demonstration of these capabilities, several weakly absorbing solutions were examined, with refractive indices in the range from 1.3330 to 1.4553 and with absorption coefficients in the range 0-16 cm-1. The new detection strategy is likely to be important in applications in which sample coloration varies and when it is necessary to compensate for variations in the refractive index of a sample.

Absorption↗

TCRspec: A Recognition Interface-Informed Multimodal Method for TCR-pMHC Specificity Prediction.

Specific recognition between T-cell receptors (TCRs) and peptide-major histocompatibility complexes (pMHCs) is central to adaptive immunity, yet accurate prediction of TCR-pMHC specificity remains challenging. Existing models mainly rely on sequence features or isolated molecular structures, limiting their ability to capture interface-level determinants within the ternary recognition complex. Here, we constructed the multimodal TCR-pMHC ternary complex (MM-TCR) data set, integrating paired TCR-pMHC sequences, V/J gene annotations, and modeled TCR-pMHC complex structures refined by short molecular dynamics-based relaxation. Based on MM-TCR, we developed TCRspec, an interpretable multimodal framework combining sequence embeddings, gene-usage features, and complex-level structural representations. Under a stringent CD-HIT TCR-cluster-disjoint split, TCRspec achieved an average AUROC of 0.896 and AUPRC of 0.882 across seven antigen-specific test data sets, outperforming representative baseline models. Cross-validation and ablation analyses confirmed the contribution of ternary complex structural information and MD-refined structures. In independent OOD peptide-TCR systems, TCRspec retained discriminative performance and identified model-inferred peptide positions associated with TCR recognition, providing a structure-informed framework for TCR specificity prediction.

Receptors, Antigen, T-Cell↗

Magneto/optical annexin V, a multimodal protein.

Multimodal proteins, or proteins labeled with both fluorescent and magnetic reporter groups, can be used in a wide range of applications including FACS or fluorescence microscopy, MRI and or near-infrared based optical imaging, or to fractionate cells by magnetic cell sorting. A problem with multimodal proteins, however, is the need to maximize bioactivity, often achieved by minimizing the number of modification points of the protein, while attaching fluorescent and magnetic labels. Here we describe the synthesis of a magneto/optical form of annexin V, achieved by reacting the amino-CLIO nanoparticle with Cy5.5 and SPDP, to produce a fluorescent, sulfhydryl reactive nanoparticle. A single reactive sulfhydryl group was added to annexin V by reaction with SATA that preserved the protein's ability to bind apoptotic Jurkat T cells. Reacting SATAylated annexin V with an SPDP activated nanoparticle yielded Anx-CLIO-Cy5.5, a magneto/optical form of annexin V. The binding of Anx-CLIO-Cy5.5 was specific for apoptotic Jurkat T cells and had an EC(50) of 3.66 nM. This was comparable to the strength of the interaction of unmodified annexin V with apoptotic cells, measured as the displacement of FITC-annexin by annexin V (2.4 nM). Our conjugation strategy preserves the strength of the interaction between annexin V and apoptotic cells, while yielding a probe, Anx-CLIO-Cy5.5, that is readily detectable by standard MR imaging or NIRF optical methods.

Annexin A5↗

Multimode ligand binding in receptor site modeling: implementation in CoMFA.

Receptor site modeling methods usually use one binding mode (conformation and/or orientation) for each ligand in a 1:1 complex with receptor. Multiple modes should be considered instead because (1). they have frequently been observed experimentally; (2). in a series, ligands can bind in single yet different modes; and (3). a series may only exhibit one but unknown mode and a few plausible modes must be examined. For multimode binding, the observed ligand/receptor association constant is the sum of the association constants that characterize individual binding modes. This relation, when applied to Comparative Molecular Field Analysis (CoMFA), results in a dependence of the observed binding energy on the probe energies that is nonlinear in optimized parameters. The dependence was linearized to allow parameter optimization by the partial least-squares method that was used iteratively until self-consistency. In addition to the standard CoMFA output, the procedure objectively selects one or a few optimal binding modes out of a dozen or more modes that are considered for each ligand. The approach was applied to published data for binding of 34 polychlorinated dibenzofurans to the aryl hydrocarbon receptor. Descriptive and predictive abilities of the 16-mode model were significantly better than for the one-, two-, and four-mode models. Predominantly, edge-aligned modes were selected that are seldom used in CoMFA. Since inclusion of multimode binding only changes the form of the correlation equation and does not affect the number of optimized parameters, the improvement is believed to be due to a more realistic description.

Algorithms↗

Biocompatible heterostructured nanoparticles for multimodal biological detection.

Hybrid nanoparticles are of significant interest primarily because of their innate multifunctional capabilities. These capabilities can be exploited when hybrid nanoparticles are used for applications in the biomedical sciences in particular, where they are utilized as multimodal nanoplatforms for sensing, imaging, and therapy of biological targets. However, the realization of their biomedical applications has been difficult, in part because of a lack of high quality hybrid nanoparticles which possess high aqueous colloidal stability and biocompatibility while retaining their multifunctionalities. Here, we present the development of inorganic heterodimer nanoparticles of FePt-Au with multifunctional capabilities including catalytic growth effects, magnetic resonance (MR) contrast effects, optical signal enhancing properties, and high colloidal stability and biocompatibility. Their multimodal capabilities for biological detection are demonstrated through their utilizations in the patterned biochip based detection of avidin-biotin interaction as well as in molecular MR imaging of neuroblastoma cells.

Biocompatible Materials↗