ABSTRACT
Background and Objectives: Iodinated Contrast Media (ICM) is used daily in many imaging departments worldwide. The main risk associated with ICM is hypersensitivity. When a severe hypersensitivity reaction is not properly managed and treated swiftly, it may be fatal. Currently, there is no data to demonstrate how ICM sensitivity affects the prognosis of cardiac patients, especially those diagnosed with ST elevation myocardial infarction (STEMI), in whom urgent coronary angiography is indicated. This study aimed to identify and characterize this relationship. Materials and Methods: We included patients hospitalized with STEMI between 2016 and 2019 from the National Inpatient Sample. The population was compared based on ICM sensitivity status, sensitive vs. non-sensitive. The primary endpoint was in-hospital mortality, with additional endpoints: length of stay and in-hospital complications. Results: The study included 664,620 STEMI patients, of whom 4905 (0.7%) were diagnosed with ICM sensitivity. ICM-sensitive patients were older, more often white, females, and had more comorbidities and cardiovascular risk factors. Both groups show similarities in management but are slightly less probable to undergo PCI or CABG. Multivariable logistic regression models found that the ICM-sensitive population had similar odds of in-hospital mortality (OR: 1.02, 95% CI: 0.89-1.16) and MACCE (OR: 1.05, 95% CI: 0.95-1.16), and less major bleeding (OR: 0.73, 95% CI: 0.60-0.87). Conclusions: Our study found that ICM sensitivity status was not a significant factor for worse prognosis in patients hospitalized with STEMI.
Subject(s)
Contrast Media , Hospital Mortality , ST Elevation Myocardial Infarction , Humans , Female , Contrast Media/adverse effects , Male , ST Elevation Myocardial Infarction/mortality , Middle Aged , Aged , Prognosis , Risk Factors , Aged, 80 and over , Logistic Models , Iodine/adverse effectsABSTRACT
BACKGROUND: Finding the balance between the reduction in ischemic events and bleeding complications is crucial for the success of percutaneous coronary intervention (PCI). The activated clotting time (ACT) is used routinely worldwide to monitor and titrate anticoagulation therapy with unfractionated heparin (UFH) during the procedure. OBJECTIVES: We aimed to test the accuracy of ACT measurements from the guiding catheter compared to the arterial access sheath. METHODS: Patients undergoing PCI with UFH therapy were prospectively enrolled. Blood samples were drawn from the coronary guide catheter and the arterial access sheath. ACT values were determined in the same ACT machine, and potential interactions with clinical variables were analyzed. RESULTS: The study included 331 patients with post PCI ACT measurements. The mean ACT value of the catheter samples was statistically higher than the arterial access sample [294 ± 77 s Vs. 250 ± 60 s, p < 0.001]. The mean difference between the guiding catheter and the arterial line sheath samples was 43 ± 27 s (P < 0.001). We found that in 101/331 [30 %] patients the ACT from the guiding catheter was above 250 s, while from the access sheath it was below 250 s. Notably, in 40/331 [12 %] the ACT from the guiding catheter was above 200 s, while from the access sheath it was below 200 s. CONCLUSIONS: Large proportion of patient may be considered to have therapeutic ACT if measured from guide catheter during PCI, while the corresponding ACT from arterial sheath is subtherapeutic. This difference may have clinical and safety significance.
ABSTRACT
The default mode network (DMN) is the main large-scale network of the resting brain and the PCC/precuneus is a major hub of this network. Glutamate and GABA (γ-amino butyric acid) are the main excitatory and inhibitory neurotransmitters in the CNS, respectively. We studied glutamate and GABA concentrations in the PCC/precuneus via magnetic resonance spectroscopy (MRS) at 7T in relation to age and correlated them with functional connectivity between this region and other DMN nodes in ten healthy right-handed volunteers ranging in age between 23-68 years. Mean functional connectivity of the PCC/precuneus to the other DMN nodes and the glutamate/GABA ratio significantly correlated with age (r = 0.802, p = 0.005 and r = 0.793, p = 0.006, respectively) but not with each other. Glutamate and GABA alone did not significantly correlate with age nor with functional connectivity within the DMN. The glutamate/GABA ratio and functional connectivity of the PCC/precuneus are, therefore, independent age-related biomarkers of the DMN and may be combined in a multimodal pipeline to study DMN alterations in various disease states.
Subject(s)
Glutamic Acid/analysis , Nerve Net/physiology , Parietal Lobe/metabolism , Rest/physiology , gamma-Aminobutyric Acid/analysis , Adult , Age Factors , Aged , Brain Mapping/methods , Female , Glutamic Acid/metabolism , Healthy Volunteers , Humans , Magnetic Resonance Spectroscopy/methods , Male , Middle Aged , Multiparametric Magnetic Resonance Imaging/methods , Nerve Net/diagnostic imaging , Parietal Lobe/diagnostic imaging , Young Adult , gamma-Aminobutyric Acid/metabolismABSTRACT
BACKGROUND AND PURPOSE: Derangements in brain glutamate, glutathione, and γ-amino butyric acid (GABA) are implicated in a range of neurological disorders. Reliable methods to measure these compounds non-invasively in vivo are needed. We evaluated the reproducibility of their measurements in brain regions involved in the default mode network using quantitative MRS at 7-Tesla in healthy individuals. METHODS: Ten right-handed healthy volunteers underwent 7-Tesla MRI scans on 2 separate days, not more than 2 weeks apart. On each day two scanning sessions took place, with a re-positioning break in between. High-resolution isotropic anatomical scans were acquired prior to each scan, followed by single-voxel 1H-MRS using the STEAM pulse sequence on an 8 mL midline cubic voxel, positioned over the posterior cingulate and precuneus regions. Concentrations were corrected for partial-volume effects. RESULTS: Maximal Cramér-Rao lower bounds for glutamate, glutathione, and GABA were 2.0, 8.0, and 14.0%, respectively. Mean coefficients of variation within sessions were 5.9 ± 4.8%, 9.3 ± 7.6%, and 11.5 ± 8.8%, and between sessions were 4.6 ± 4.5%, 8.3 ± 5.7%, and 9.2 ± 8.7%, respectively. The mean (±SD) Dice's coefficient for voxel overlap was 90 ± 4% within sessions and 86 ± 7% between sessions. CONCLUSION: Glutamate, glutathione, and GABA can be reliably quantified using STEAM MRS at 7-Tesla from the posterior cingulate and precuneus cortices of healthy human subjects. STEAM MRS at 7-Tesla may be used to study the metabolic behavior of this important resting-state hub in various disease states.
ABSTRACT
OBJECTIVE: The posterior cingulate cortex (PCC)/precuneus is a key hub of the default mode network, whose function is known to be altered in epilepsy. Glutamate and γ-aminobutyric acid (GABA) are the main excitatory and inhibitory neurotransmitters in the central nervous system, respectively. Glutathione (GSH) is the most important free radical scavenging compound in the brain. Quantification of these molecules by magnetic resonance spectroscopy (MRS) up to 4 T is limited by overlapping resonances from other molecules. In this study, we used ultra-high-field (7 T) MRS to quantify their concentrations in patients with different epilepsy syndromes. METHODS: Nineteen patients with temporal lobe epilepsy (TLE) and 16 with idiopathic generalized epilepsy (IGE) underwent magnetic resonance imaging scans using a 7-T research scanner. Single-voxel (8 cm3 ) MRS, located in the PCC/precuneus, was acquired via stimulated echo acquisition mode. Their results were compared to 10 healthy volunteers. RESULTS: Mean concentrations of glutamate, GABA, and the glutamate/GABA ratio did not differ between the IGE, TLE, and healthy volunteer groups. The mean ± SD concentration of GSH was 1.9 ± 0.3 mmol·L-1 in healthy controls, 2.0 ± 0.2 mmol·L-1 in patients with TLE, and 2.2 ± 0.4 mmol·L-1 in patients with IGE. One-way analysis of variance with post hoc Tukey-Kramer test revealed a significant difference in the concentration of GSH between patients with IGE and controls (P = .03). Short-term seizure freedom in patients with epilepsy was predicted by an elevated concentration of glutamate in the PCC/precuneus (P = .01). In patients with TLE, the concentration of GABA declined with age (P = .03). SIGNIFICANCE: Patients with IGE have higher concentrations of GSH in the PCC/precuneus than healthy controls. There is no difference in the concentrations of glutamate and GABA, or their ratio, in the PCC/precuneus between patients with IGE, patients with TLE, and healthy controls. Measuring the concentration of glutamate in the PCC/precuneus may assist with predicting drug response.
Subject(s)
Epilepsy/metabolism , Glutamic Acid/analysis , Glutathione/analysis , Gyrus Cinguli/chemistry , Parietal Lobe/chemistry , gamma-Aminobutyric Acid/analysis , Adult , Aged , Case-Control Studies , Epilepsy, Generalized/metabolism , Epilepsy, Temporal Lobe/metabolism , Humans , Magnetic Resonance Spectroscopy , Male , Middle Aged , Young AdultABSTRACT
The default mode network (DMN) is a major neuronal network that deactivates during goal-directed tasks. Recent advances in neuroimaging have shed light on its structure and function. Alterations in the DMN are increasingly recognized in a range of neurological and psychiatric conditions including epilepsy. This review first describes the current understanding of the DMN in health, normal aging, and disease as it is acquired via resting-state functional magnetic resonance imaging (MRI), before focusing on how it is affected in various types of focal and generalized epilepsy. These findings support the potential use of DMN parameters as future biomarkers in epilepsy research, diagnosis, and management.
Subject(s)
Brain/diagnostic imaging , Default Mode Network/diagnostic imaging , Epilepsy/diagnostic imaging , Magnetic Resonance Imaging/methods , Rest , Brain/physiopathology , Brain Mapping/methods , Default Mode Network/physiopathology , Epilepsy/physiopathology , Female , Humans , Male , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Rest/physiologyABSTRACT
BACKGROUND: Malignancy is a known risk factor for venous thromboembolism; however, the association with arterial thromboembolic events remains unclear. OBJECTIVES: To examine the association between non-ST-elevation myocardial infarction (NSTEMI) and non-significant coronary artery disease (CAD) and the presence of new or occult malignancy. METHODS: An observational cohort, single-center study was performed 2010-2015. Adult patients with NSTEMI, who underwent coronary angiography and had no significant coronary lesion, were included. Using propensity score matching, we created a 2:1 matched control group of adults with NSTEMI, and significant coronary artery disease. Risk factors for new or occult malignancy were assessed using multivariate backward stepwise logistic regression analysis. The primary outcome was new or occult malignancy, defined as any malignancy diagnosed in the 3 months prior and 6 months following the myocardial infarction (MI). RESULTS: During the study period, 174 patients who presented with MI with non-obstructive coronary arteries were identified. The matched control group included 348 patients. There was no significant difference in the group demographics, past medical history, or clinical presentation. The incidence of new or occult malignancy in the study group was significantly higher (7/174, 4% vs. 3/348, 0.9%, P = 0.019). NSTEMI with non-significant CAD was an independent risk factor for occult malignancy (odds ratio [OR] 4.6, 95% confidence interval [95%CI] 1.1-18.7). Other risk factors included active smoking (OR 11.2, 95%CI 2.5-49.1) and age (OR 1.1, 95%CI 1.03-1.17). CONCLUSIONS: NSTEMI with non-significant CAD may be a presenting or early marker of malignancy and warrants further investigation.
Subject(s)
Coronary Artery Disease/epidemiology , Neoplasms/epidemiology , Non-ST Elevated Myocardial Infarction/epidemiology , Cohort Studies , Comorbidity , Coronary Angiography , Coronary Vessels/diagnostic imaging , Female , Humans , Israel/epidemiology , Male , Middle Aged , Non-ST Elevated Myocardial Infarction/diagnostic imaging , Retrospective Studies , Risk FactorsABSTRACT
The goal of protein engineering and design is to identify sequences that adopt three-dimensional structures of desired function. Often, this is treated as a single-objective optimization problem, identifying the sequence-structure solution with the lowest computed free energy of folding. However, many design problems are multi-state, multi-specificity, or otherwise require concurrent optimization of multiple objectives. There may be tradeoffs among objectives, where improving one feature requires compromising another. The challenge lies in determining solutions that are part of the Pareto optimal set-designs where no further improvement can be achieved in any of the objectives without degrading one of the others. Pareto optimality problems are found in all areas of study, from economics to engineering to biology, and computational methods have been developed specifically to identify the Pareto frontier. We review progress in multi-objective protein design, the development of Pareto optimization methods, and present a specific case study using multi-objective optimization methods to model the tradeoff between three parameters, stability, specificity, and complexity, of a set of interacting synthetic collagen peptides.
ABSTRACT
BACKGROUND: Use of TPA to treat patients with acute ischemic stroke was introduced in Assaf Harofeh Medical Center (AHMC) in Israel in November 2007 initially with strict adherence to the inclusion/exclusion criteria of the pivotal NINDS TPA studies published in 1995. The treatment window was expanded in 2010 to 4.5h following the results of ECASS-III. Application of the 2013 AHA/ASA Guidelines resulted in further expanded inclusion and relaxed exclusion criteria. DESIGN/METHODS: A retrospective chart review was conducted of patients who received TPA at AHMC to evaluate the additional impact of applying the 2013 guidelines. Number of patients treated, outcomes at discharge, and safety were compared between two periods: May 2011-January 2013 (the 21months preceding the 2013 Guidelines); and February 2013-October 2014 (the 21months after publication of the 2013 Guidelines). Statistical analysis was done using z-tests for differences between proportions, and t-tests to compare means. RESULTS: 63 patients were treated during the immediate pre-2013 Guideline period (36/year, or approximately 5% of patients with ischemic stroke), and 105 during the post-2013 Guidelines period (60/year, approximately 8.3% of patients with ischemic stroke) (p<0.001). During the two periods, respectively: discharges home were 22(34%) and 55(52%) (p<0.05); facility discharges were 29(46%) and 33(31%); and inter-hospital transfers were 6(9%), and 11(10% of treated patients). Most transfers were for endovascular treatment. Total treatment-related symptomatic bleeds in the two periods, respectively, was: 4(6%) and 4(4%), and the number of in-hospital deaths was 6 (9%) and 6 (6%) (unchanged). CONCLUSIONS: Application of the 2013 AHA/ASA Guidelines resulted in a 64% increase in the number of acute ischemic stroke patients treated with TPA at AHMC with no worsening of aggregate outcomes and no increase in bleeds or deaths.
Subject(s)
Brain Ischemia/complications , Clinical Medicine/standards , Fibrinolytic Agents/therapeutic use , Stroke/drug therapy , Stroke/etiology , Tissue Plasminogen Activator/therapeutic use , Adult , Aged , Aged, 80 and over , Female , Hospitals/standards , Humans , Israel/epidemiology , Male , Middle Aged , Retrospective Studies , Stroke/epidemiology , Treatment OutcomeABSTRACT
The metabolic profiles and composition of storage reserves of agricultural crop seeds are strongly regulated by heritable and environmental factors. Yet, very little is known about the genetic and environmental determinants of adaptive metabolic variation amongst wild type as well as transgenic seed populations derived from the same genetic background, grown under natural field conditions. The goal of the current study was to investigate the effects of natural environmental conditions on wild type and transgenic soybean seeds expressing a feedback-insensitive form of cystathionine γ-synthase, a methionine main regulatory enzyme. The seeds were grown in four geographically distinct habitats in China and then assayed for primary metabolic profiles using gas chromatography mass spectrometry, morphological traits and storage reserve accumulation. The analyses revealed changes in the levels of primary metabolites which evidently exhibited high correlation to methionine regardless of changes in environmental conditions. The environment, however, constituted a major determinant of metabolic profiles amongst seeds, as much more metabolites were observed to be affected by this variable, particularly along the north-to-south latitudinal gradient. The observations suggest that metabolic variation amongst seeds grown under natural field conditions depends upon the complex relationships existing amongst their genetic background and the environmental conditions characterizing their cultivation areas.
Subject(s)
Gene-Environment Interaction , Glycine max/metabolism , Plants, Genetically Modified/metabolism , Arabidopsis/genetics , Carbon-Oxygen Lyases/genetics , Carbon-Oxygen Lyases/metabolism , Environment , Plants, Genetically Modified/genetics , Seeds/anatomy & histology , Seeds/metabolism , Glycine max/anatomy & histology , Glycine max/geneticsABSTRACT
Protein-protein interactions (PPI) play a critical role in regulating many cellular processes. Finding novel PPI inhibitors that interfere with specific binding of two proteins is considered a great challenge, mainly due to the complexity involved in characterizing multi-molecular systems and limited understanding of the physical principles governing PPIs. Here we show that the combination of virtual screening techniques, which are capable of filtering a large library of potential small molecule inhibitors, and a unique secondary screening by isothermal titration calorimetry, a label-free method capable of observing direct interactions, is an efficient tool for finding such an inhibitor. In this study we applied this strategy in a search for a small molecule capable of interfering with the interaction of the tumor-suppressor p53 and the E3-ligase MDM2. We virtually screened a library of 15 million small molecules that were filtered to a final set of 80 virtual hits. Our in vitro experimental assay, designed to validate the activity of mixtures of compounds by isothermal titration calorimetry, was used to identify an active molecule against MDM2. At the end of the process the small molecule (4S,7R)-4-(4-chlorophenyl)-5-hydroxy-2,7-dimethyl-N-(6-methylpyridin-2-yl)-4,6,7,8 tetrahydrIoquinoline-3-carboxamide was found to bind MDM2 with a dissociation constant of ~2 µM. Following the identification of this single bioactive compound, spectroscopic measurements were used to further characterize the interaction of the small molecule with the target protein. 2D NMR spectroscopy was used to map the binding region of the small molecule, and fluorescence polarization measurement confirmed that it indeed competes with p53.
Subject(s)
Calorimetry , Drug Delivery Systems , Small Molecule Libraries/pharmacology , Computer Simulation , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Humans , Phosphoric Monoester Hydrolases/chemistry , Phosphoric Monoester Hydrolases/metabolism , Proto-Oncogene Proteins c-mdm2/chemistry , Proto-Oncogene Proteins c-mdm2/metabolismABSTRACT
The control of quantum system dynamics is generally performed by seeking a suitable applied field. The physical objective as a functional of the field forms the quantum control landscape, whose topology, under certain conditions, has been shown to contain no critical point suboptimal traps, thereby enabling effective searches for fields that give the global maximum of the objective. This paper addresses the structure of the landscape as a complement to topological critical point features. Recent work showed that landscape structure is highly favorable for optimization of state-to-state transition probabilities, in that gradient-based control trajectories to the global maximum value are nearly straight paths. The landscape structure is codified in the metric R ≥ 1.0, defined as the ratio of the length of the control trajectory to the Euclidean distance between the initial and optimal controls. A value of R = 1 would indicate an exactly straight trajectory to the optimal observable value. This paper extends the state-to-state transition probability results to the quantum ensemble and unitary transformation control landscapes. Again, nearly straight trajectories predominate, and we demonstrate that R can take values approaching 1.0 with high precision. However, the interplay of optimization trajectories with critical saddle submanifolds is found to influence landscape structure. A fundamental relationship necessary for perfectly straight gradient-based control trajectories is derived, wherein the gradient on the quantum control landscape must be an eigenfunction of the Hessian. This relation is an indicator of landscape structure and may provide a means to identify physical conditions when control trajectories can achieve perfect linearity. The collective favorable landscape topology and structure provide a foundation to understand why optimal quantum control can be readily achieved.
ABSTRACT
Knowledge of the Hessian matrix at the landscape optimum of a controlled physical observable offers valuable information about the system robustness to control noise. The Hessian can also assist in physical landscape characterization, which is of particular interest in quantum system control experiments. The recently developed landscape theoretical analysis motivated the compilation of an automated method to learn the Hessian matrix about the global optimum without derivative measurements from noisy data. The current study introduces the forced optimal covariance adaptive learning (FOCAL) technique for this purpose. FOCAL relies on the covariance matrix adaptation evolution strategy (CMA-ES) that exploits covariance information amongst the control variables by means of principal component analysis. The FOCAL technique is designed to operate with experimental optimization, generally involving continuous high-dimensional search landscapes (â³30) with large Hessian condition numbers (â³10^{4}). This paper introduces the theoretical foundations of the inverse relationship between the covariance learned by the evolution strategy and the actual Hessian matrix of the landscape. FOCAL is presented and demonstrated to retrieve the Hessian matrix with high fidelity on both model landscapes and quantum control experiments, which are observed to possess nonseparable, nonquadratic search landscapes. The recovered Hessian forms were corroborated by physical knowledge of the systems. The implications of FOCAL extend beyond the investigated studies to potentially cover other physically motivated multivariate landscapes.
Subject(s)
Algorithms , Models, Theoretical , Numerical Analysis, Computer-Assisted , Rheology/methods , Computer SimulationABSTRACT
The applicability of adaptive femtosecond pulse shaping is studied for achieving selectivity in the photoionization of low-density polyatomic targets. In particular, optimal dynamic discrimination (ODD) techniques exploit intermediate molecular electronic resonances that allow a significant increase in the photoionization efficiency of nitromethane with shaped near-infrared femtosecond pulses. The intensity bias typical of high-photon number, nonresonant ionization is accounted for by reference to a strictly intensity-dependent process. Closed-loop adaptive learning is then able to discover a pulse form that increases the ionization efficiency of nitromethane by â¼150%. The optimally induced molecular dynamics result from entry into a region of parameter space inaccessible with intensity-only control. Finally, the discovered pulse shape is demonstrated to interact with the molecular system in a coherent fashion as assessed from the asymmetry between the response to the optimal field and its time-reversed counterpart.
Subject(s)
Methane/analogs & derivatives , Nitroparaffins/chemistry , Photochemical Processes , Photons , Air , Methane/chemistry , Time FactorsABSTRACT
While the motivation and usefulness of niching methods is beyond doubt, the relaxation of assumptions and limitations concerning the hypothetical search landscape is much needed if niching is to be valid in a broader range of applications. Upon the introduction of radii-based niching methods with derandomized evolution strategies (ES), the purpose of this study is to address the so-called niche radius problem. A new concept of an adaptive individual niche radius is applied to niching with the covariance matrix adaptation evolution strategy (CMA-ES). Two approaches are considered. The first approach couples the radius to the step size mechanism, while the second approach employs the Mahalanobis distance metric with the covariance matrix mechanism for the distance calculation, for obtaining niches with more complex geometrical shapes. The proposed approaches are described in detail, and then tested on high-dimensional artificial landscapes at several levels of difficulty. They are shown to be robust and to achieve satisfying results.
Subject(s)
Algorithms , Computer Simulation , Models, Theoretical , Search Engine/methodsABSTRACT
We have previously demonstrated that rat bone in vivo and rat bone cells in vitro, responded sex-specifically to gonadal steroids in stimulation of the specific activity of the BB isozyme of creatine kinase (CK), a marker for hormonal responsiveness. Pre-treatment with vitamin D analogs up-regulated the sex-specific responsiveness and sensitivity to gonadal steroids. We also found that mice cultured femoral bone marrow (BM) in the presence of dexamethasone (DEX) and 1,25(OH)2D3 (1,25D) or both differentiated into osteoblast-like cells (Obs), which acquired sex-specific responsiveness to gonadal steroids. This response was significantly augmented in the presence of both agents. In the present study, we examined the effect of age, sex and vitamin D non-hypercalcemic analogs on the differentiation of rat derived femoral BM into Obs. In female or male derived BM from intact but not gonadectomized rats DEX and DEX+1,25D increased the constitutive levels of CK. BM derived from old females showed lower stimulation of CK than BM originated from young females by estradiol (E2) or raloxifene (Ral) in the presence of both DEX and 1,25D. The non-hypercalcemic analogs of vitamin D: CB 1093 (CB), EB 1089 (EB) and MC 1288 (MC) were more effective than 1,25D in both age groups in stimulating CK in the absence of DEX. In the presence of DEX, there was a further increase in CK with the same differential effectiveness. BM from gonadectomized male or female rats lost the sex-specific response, responding to both E2 and dihydrotestosterone (DHT). BM derived from both intact and gonadectomized males and females, growing with DEX or DEX+1,25D showed increased specific activity of constitutive levels of alkaline phodphatase (AP). No significant stimulation of AP was seen in any BM by gonadal steroids. These findings suggest that manipulation of the hormonal milieu in early stages of differentiation sequence of Obs determines the subsequent selective responsiveness of the developing bone tissue to sex steroids. Also non-calcemic vitamin D analogs were more effective in this process than 1,25D and showed activity even in the absence of DEX and may be applied to the differentiation process for bone tissue engineering.
Subject(s)
Aging , Bone Marrow Cells/cytology , Calcitriol/analogs & derivatives , Osteoblasts/cytology , Sex Characteristics , Alkaline Phosphatase/metabolism , Animals , Bone Marrow Cells/enzymology , Calcitriol/pharmacology , Cell Differentiation/drug effects , Cells, Cultured , Creatine Kinase/metabolism , Dexamethasone/pharmacology , Dihydrotestosterone/pharmacology , Estradiol/pharmacology , Female , Male , Orchiectomy , Osteoblasts/physiology , Ovariectomy , Raloxifene Hydrochloride/pharmacology , Rats , Rats, Inbred WKYABSTRACT
Control of cancer, neuropathic, and postoperative pain is frequently inadequate or compromised by debilitating side effects. Inhibition or removal of certain nociceptive neurons, while retaining all other sensory modalities and motor function, would represent a new therapeutic approach to control severe pain. The enriched expression of transient receptor potential cation channel, subfamily V, member 1 (TRPV1; also known as the vanilloid receptor, VR1) in nociceptive neurons of the dorsal root and trigeminal ganglia allowed us to test this concept. Administration of the potent TRPV1 agonist resiniferatoxin (RTX) to neuronal perikarya induces calcium cytotoxicity by opening the TRPV1 ion channel and selectively ablates nociceptive neurons. This treatment blocks experimental inflammatory hyperalgesia and neurogenic inflammation in rats and naturally occurring cancer and debilitating arthritic pain in dogs. Sensations of touch, proprioception, and high-threshold mechanosensitive nociception, as well as locomotor function, remained intact in both species. In separate experiments directed at postoperative pain control, subcutaneous administration of RTX transiently disrupted nociceptive nerve endings, yielding reversible analgesia. In human dorsal root ganglion cultures, RTX induced a prolonged increase in intracellular calcium in vanilloid-sensitive neurons, while leaving other, adjacent neurons unaffected. The results suggest that nociceptive neuronal or nerve terminal deletion will be effective and broadly applicable as strategies for pain management.
Subject(s)
Diterpenes/administration & dosage , Pain Management , Pain Measurement/drug effects , Receptors, Drug/metabolism , Adult , Analgesia/methods , Animals , Calcium/toxicity , Cells, Cultured , Diterpenes/metabolism , Dogs , Dose-Response Relationship, Drug , Extravasation of Diagnostic and Therapeutic Materials/prevention & control , Ganglia, Spinal/cytology , Ganglia, Spinal/metabolism , Humans , Male , Microinjections , Neurons, Afferent/drug effects , Neurons, Afferent/metabolism , Nociceptors/metabolism , Pain Measurement/methods , Rats , Rats, Sprague-Dawley , Stereotaxic Techniques , Time Factors , Trigeminal Ganglion/drug effectsABSTRACT
OBJECT: Spinal meningiomas occur most frequently in older patients. They are well-circumscribed and slow-growing tumors that are associated with good patient outcomes following surgery. Spinal meningiomas occurring in younger patients may be more aggressive, with a worse prognosis. The authors present their 21-year experience with spinal meningiomas in patients younger than 50 years of age. METHODS: The authors reviewed data obtained in 40 patients (age < 50 years) treated at the Mayo Clinic, Rochester, during the past 21 years; in all cases the lesions were histologically confirmed spinal meningiomas. Five men (12.5%) and 35 women (87.5%) (mean age 34.5 +/- 10.9 years) underwent 52 operations for 41 tumors. The mean follow-up duration was 82 +/- 93 months (range 0-445 months). The data obtained in these patients were compared with those derived from a random control cohort of 40 patients older than age 50 years in whom spinal meningiomas were resected at the Mayo Clinic during a similar period. In this cohort, there were 33 women and seven men whose mean age was 67.1 +/- 9.5 years. The mean follow-up duration for the older group was 88 +/- 72.3 months (range 18-309 months). Compared with the random cohort of older patients, younger patients there tended to have more tumors located in the cervical spine (39%) as well as a greater number of predisposing factors such as neurofibromatosis Type 2, radiation exposure, or trauma. Nine (22%) of the patients younger than 50 years of age required reoperation for residual or recurrent tumor compared with two (5%) in the older patient control group. The overall mortality rate at the completion of the study for the younger patients was 10%. CONCLUSIONS: Spinal meningiomas in younger patients have a worse prognosis than similar tumors in older patients.